Effective December 6, 2006, this report has been made publicly available in accordance with Section 734.3(b)(3) and published in accordance with Section 734.7 of the U.S. Export Administration Regulations. As a result of this publication, this report is subject to only copyright protection and does not require any license agreement from EPRI. This notice supersedes the export control restrictions and any proprietary licensed material notices embedded in the document prior to publication.
Work Package Templates
1012288
Work Package Templates
1012288 Technical Update, February 2007
EPRI Project Manager L. Rogers
ELECTRIC POWER RESEARCH INSTITUTE 3420 Hillview Avenue, Palo Alto, California 94304-1338 • PO Box 10412, Palo Alto, California 94303-0813 • USA 800.313.3774 • 650.855.2121 •
[email protected] • www.epri.com
DISCLAIMER OF WARRANTIES AND LIMITATION OF LIABILITIES THIS DOCUMENT WAS PREPARED BY THE ORGANIZATION(S) NAMED BELOW AS AN ACCOUNT OF WORK SPONSORED OR COSPONSORED BY THE ELECTRIC POWER RESEARCH INSTITUTE, INC. (EPRI). NEITHER EPRI, ANY MEMBER OF EPRI, ANY COSPONSOR, THE ORGANIZATION(S) BELOW, NOR ANY PERSON ACTING ON BEHALF OF ANY OF THEM: (A) MAKES ANY WARRANTY OR REPRESENTATION WHATSOEVER, EXPRESS OR IMPLIED, (I) WITH RESPECT TO THE USE OF ANY INFORMATION, APPARATUS, METHOD, PROCESS, OR SIMILAR ITEM DISCLOSED IN THIS DOCUMENT, INCLUDING MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, OR (II) THAT SUCH USE DOES NOT INFRINGE ON OR INTERFERE WITH PRIVATELY OWNED RIGHTS, INCLUDING ANY PARTY'S INTELLECTUAL PROPERTY, OR (III) THAT THIS DOCUMENT IS SUITABLE TO ANY PARTICULAR USER'S CIRCUMSTANCE; OR (B) ASSUMES RESPONSIBILITY FOR ANY DAMAGES OR OTHER LIABILITY WHATSOEVER (INCLUDING ANY CONSEQUENTIAL DAMAGES, EVEN IF EPRI OR ANY EPRI REPRESENTATIVE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES) RESULTING FROM YOUR SELECTION OR USE OF THIS DOCUMENT OR ANY INFORMATION, APPARATUS, METHOD, PROCESS, OR SIMILAR ITEM DISCLOSED IN THIS DOCUMENT. ORGANIZATION(S) THAT PREPARED THIS DOCUMENT Electric Power Research Institute (EPRI)
This is an EPRI Technical Update report. A Technical Update report is intended as an informal report of continuing research, a meeting, or a topical study. It is not a final EPRI technical report.
NOTE For further information about EPRI, call the EPRI Customer Assistance Center at 800.313.3774 or e-mail
[email protected]. Electric Power Research Institute, EPRI, and TOGETHER SHAPING THE FUTURE OF ELECTRICITY are registered service marks of the Electric Power Research Institute, Inc. Copyright © 2007 Electric Power Research Institute, Inc. All rights reserved.
CITATIONS This document was prepared by Electric Power Research Institute (EPRI) Nuclear Maintenance Applications Center (NMAC) 1300 W.T. Harris Boulevard Charlotte, NC 28262 Principal Investigator J. West This document describes research sponsored by the Electric Power Research Institute (EPRI). This publication is a corporate document that should be cited in the literature in the following manner: Work Package Templates. EPRI, Palo Alto, CA: 2007. 1012288.
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REPORT SUMMARY This Work Package Templates Guide provides fossil plant maintenance personnel with assorted inspection, minor repair or overhaul templates for various pieces of plant equipment. This guide will assist plant maintenance personnel in improving the efficiency, reliability and reducing the maintenance costs for associated with maintenance on selected pieces of equipment. Background In parallel with this Technical Update EPRI developed the following document that formed the basis for the template format utilized within this report: •
Technical Report 1014547, “Maintenance Work Package Planning Guidance for Fossil Power Plant Personnel” Currently there is no means to share lessons learned from maintenance activities among fossil utilities and to benefit from the efficiencies learned from using enhanced/optimized work packages. In many cases, work packages are repeatedly prepared for equipment that is common among most fossil power plants. A compilation of work package templates that provides information for the development of specific work orders will improve the efficiency and technical adequacy or work packages. These templates will be provided for common maintenance activities by component and in a standardized format. Objectives The objective of this report is to provide a series of work package templates for common pieces of equipment found in most fossil plants. The generic work package templates may then be used with site-specific information to develop site-specific work packages referencing site-specific procedures, vendor information and other site-specific information relevant to the work activity. Approach An introduction to work packages provides insight into the work package process, benefits that can be realized from the use of work packages and guidance on how to use the work package templates. The templates can be found useful to any maintenance organization regardless of the current level of work package development and planning. A proposed format for developing work packages is provided. The format is consistent with the provided in EPRI Technical Report 1014547, “Maintenance Work Package Planning Guidance for Fossil Power Plant Personnel” The appendices contain work package templates for a variety of different plant equipment. Various types of maintenance activities are embedded in the templates; testing, inspection, minor repair and overhaul. Most templates are generic with respect to the piece of equipment. There are some templates that are directed at specific equipment due to their widespread use. (E.g. Limitorque SB actuator, Gould 3196 pump) Some templates cover a wide range of equipment vendors and types. (E.g. Low voltage breakers and steam traps) In some cases a particular design may be featured. E.g. roll wheel pulverizer)
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Results This technical report provides an overview of work package development, a work package template format and work package templates for various pieces of equipment common to most fossil power plants. The focus of the report is to provide a work package template format and example templates from which site specific work packages may be developed. The development of site-specific work package templates that can be utilized repeatedly for maintenance activities can increase the overall effectiveness and efficiency of the maintenance organization and reduce overall maintenance costs. The report provides templates for numerous pieces of equipment that are found in most fossil power plants using a standardized format. It provides information for inspections, minor repairs or overhauls of equipment. Considerations are given to task overview, pre-job briefs, contingencies, detailed work instruction/sequence, identification or parts, tools and equipment, feedback mechanisms and proposed references. Keywords Work Control Work Planning Work Package Work Order Templates Work Instruction
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ACKNOWLEDGEMENTS EPRI wishes to acknowledge the members of the Task Advisory Group: Charlie Cassise
Detroit Edison
Clarence Nail
Dynegy
Charlie Leveridge
East Kentucky Power Cooperative
David Brawner
Entergy
Bill Hilton
Hoosier Energy Rural Electric Coop., Inc
Ken McDonald
Hoosier Energy Rural Electric Coop., Inc
Steve Blair
Hoosier Energy Rural Electric Coop., Inc
Regan Hallford
PNM
George Lum
Southern Company
Joe Tyner
Southern Company
David Egner
TVA
Howard Ray
TVA
Garry Waggoner
TXU
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CONTENTS 1 INTRODUCTION ....................................................................................................................1-1 1.1 Purpose and Scope........................................................................................................1-1 1.2 Background ....................................................................................................................1-1 1.3 Report Structure and Overview......................................................................................1-1 1.4 Glossary of Terms and Acronyms..................................................................................1-2 1.4.1 Industry Definitions and Nomenclature .................................................................1-2 1.4.2 Acronyms ..............................................................................................................1-7 1.5 Key Points ......................................................................................................................1-8 2 WORK PACKAGE TEMPLATES ...........................................................................................2-1 2.1 Introduction ....................................................................................................................2-1 2.2 Benefits of Work Package Templates ............................................................................2-3 2.3 Work Package Templates ..............................................................................................2-4 2.4 How to Use the Templates.............................................................................................2-4 2.5 Planning Walkdowns......................................................................................................2-5 3 WORK PACKAGE TEMPLATE FORMAT .............................................................................3-1 3.1 Task Overview ...............................................................................................................3-1 3.2 Pre-Job Considerations..................................................................................................3-2 3.3 Contingency Considerations ..........................................................................................3-4 3.4 Detailed Work Instructions .............................................................................................3-6 3.5 Post Maintenance Testing..............................................................................................3-8 3.6 Feedback Mechanisms ..................................................................................................3-9 3.7 References...................................................................................................................3-11 4 REFERENCES .......................................................................................................................4-1 A WORK PACKAGE TEMPLATE – BELT DRIVEN EQUIPMENT ......................................... A-1 1.0 Task Overview .............................................................................................................. A-1 1.1 Component type...................................................................................................... A-1 1.2 Equipment tag or unique equipment identifier......................................................... A-1 1.3 Scope ...................................................................................................................... A-1 1.4 Develop list of know consumable materials to be used........................................... A-1 1.5 Develop a list of know parts to be replaced ............................................................ A-1 1.6 Special tools............................................................................................................ A-1 2.0 Pre-job Brief .................................................................................................................. A-2 2.1 Evaluate potential for generation or equipment risk hazards .................................. A-2 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation ........................ A-2 2.3 Job Safety Analysis, Identifies general and specific hazards.................................. A-2 2.4 Identify permits required.......................................................................................... A-2
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2.5 Identify Environmental Consideration ..................................................................... A-3 2.6 Identify Operating Experience................................................................................. A-3 2.7 Identify Clearance/Tag out Boundary...................................................................... A-3 3.0 Contingency Considerations ......................................................................................... A-3 3.1 Identify potential scope expansion and actions due to scope expansion................ A-3 3.2 Identify individuals to contact in case certain events occur..................................... A-3 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions .......................................................................................... A-3 3.4 Develop material list for potential contingency and consumable parts.................... A-4 4.0 Detailed Work Instructions ............................................................................................ A-4 4.1 Disassembly............................................................................................................ A-4 4.2 Inspections .............................................................................................................. A-5 4.3 Alignments .............................................................................................................. A-7 4.3.1 Sheave alignment........................................................................................... A-7 4.3.2 Shaft/Bearing Alignment (required only if shaft or bearing is replaced .......... A-7 4.3.3 Adjusting belt tension ..................................................................................... A-8 4.3.3.1 Shaft deflection method......................................................................... A-8 4.3.4 Reassembly.................................................................................................... A-8 5.0 Determine PMT and PMT considerations ..................................................................... A-9 6.0 Feedback Mechanisms ................................................................................................. A-9 7.0 References.................................................................................................................... A-9 B WORK PACKAGE TEMPLATE - BOILER FEED WATER PUMP....................................... B-1 1.0 Task Overview .............................................................................................................. B-1 1.1 Component type...................................................................................................... B-1 1.2 Equipment tag or unique equipment identifier......................................................... B-1 1.3 Scope ...................................................................................................................... B-1 1.4 Develop list of know consumable materials to be used........................................... B-1 1.5 Develop a list of know parts to be replaced ............................................................ B-2 1.6 Special tools............................................................................................................ B-2 2.0 Pre-job Brief .................................................................................................................. B-2 2.1 Evaluate potential for generation or equipment risk hazards .................................. B-2 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation ........................ B-3 2.3 Job Safety Analysis, Identifies general and specific hazards.................................. B-3 2.4 Identify permits required.......................................................................................... B-3 2.5 Identify Environmental Consideration ..................................................................... B-3 2.6 Identify Operating Experience................................................................................. B-3 2.7 Identify Clearance/Tag out Boundary...................................................................... B-3 3.0 Contingency Considerations ......................................................................................... B-4 3.1 Identify potential scope expansion and actions due to scope expansion................ B-4 3.2 Identify individuals to contact in case certain events occur..................................... B-4
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3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions .......................................................................................... B-5 3.4 Develop material list for potential contingency and consumable parts.................... B-5 4.0 Detailed Work Instructions ............................................................................................ B-5 4.1 Preparations............................................................................................................ B-5 4.2 Removal of Subsystems ......................................................................................... B-6 4.3 Disassembly............................................................................................................ B-6 4.3.1 Cleaning, Inspection, Lubrication ................................................................... B-8 4.3.2 Reassembly.................................................................................................... B-9 5.0 Determine PMT and PMT considerations ................................................................... B-11 6.0 Feedback Mechanisms ............................................................................................... B-12 7.0 References.................................................................................................................. B-12 C WORK PACKAGE TEMPLATE – HEAT EXCHANGER ...................................................... C-1 1.0 Task Overview .............................................................................................................. C-1 1.1 Component type...................................................................................................... C-1 1.2 Equipment tag or unique equipment identifier......................................................... C-1 1.3 Scope ...................................................................................................................... C-1 1.4 Develop list of know consumable materials to be used........................................... C-1 1.5 Develop a list of know parts to be replaced ............................................................ C-2 1.6 Special tools............................................................................................................ C-2 2.0 Pre-job Brief .................................................................................................................. C-2 2.1 Evaluate potential for generation or equipment risk hazards .................................. C-2 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation ........................ C-3 2.3 Job Safety Analysis, Identifies general and specific hazards.................................. C-3 2.4 Identify permits required.......................................................................................... C-3 2.5 Identify Environmental Considerations.................................................................... C-4 2.6 Identify Operating Experience................................................................................. C-4 2.7 Identify Clearance/Tagout Boundary....................................................................... C-4 3.0 Contingency Considerations ......................................................................................... C-4 3.1 Identify potential scope expansion and actions due to scope expansion................ C-4 3.2 Identify individuals to contact in case certain events occur..................................... C-4 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions .......................................................................................... C-5 3.4 Develop material list for potential contingency and consumable parts.................... C-5 4.0 Detailed Work Instructions ............................................................................................ C-5 4.1 Disassembly:........................................................................................................... C-5 4.2 Cleaning: ................................................................................................................. C-7 4.3 Heat Exchanger Testing:......................................................................................... C-7 4.3.1 Leak Testing................................................................................................... C-7 4.3.1.1 Leak Testing using System Pressure .................................................... C-7 4.3.1.2 Leak Testing using Hydro Pump ........................................................... C-8
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4.4 Leak Repairs ........................................................................................................... C-8 4.4.1 Tube to Tube-Sheet Leaks............................................................................. C-8 4.4.2 Tube leaks...................................................................................................... C-9 4.5 Reassemble Heat Exchanger ............................................................................... C-10 5.0 Determine PMT and PMT considerations ................................................................... C-10 6.0 Feedback Mechanisms ............................................................................................... C-11 7.0 References.................................................................................................................. C-11 D WORK PACKAGE TEMPLATE – LOW VOLTAGE BREAKER OVERHAUL ..................... D-1 1.0 Task Overview .............................................................................................................. D-1 1.1 Component type...................................................................................................... D-1 1.2 Equipment tag or unique equipment identifier......................................................... D-1 1.3 Scope ...................................................................................................................... D-1 1.4 Develop list of know consumable materials to be used........................................... D-2 1.5 Develop a list of know parts to be replaced ............................................................ D-2 1.6 Special tools............................................................................................................ D-2 2.0 Pre-job Brief .................................................................................................................. D-3 2.1 Evaluate potential for generation or equipment risk hazards .................................. D-3 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation ........................ D-3 2.3 Job Safety Analysis, Identifies general and specific hazards.................................. D-3 2.4 Identify permits required.......................................................................................... D-4 2.5 Identify Environmental Consideration ..................................................................... D-4 2.6 Identify Operating Experience................................................................................. D-4 2.7 Identify Clearance/Tagout Boundary....................................................................... D-5 3.0 Contingency Considerations ......................................................................................... D-5 3.1 Identify potential scope expansion and actions due to scope expansion................ D-5 3.2 Identify individuals to contact in case certain events occur..................................... D-5 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions .......................................................................................... D-5 3.4 Develop material list for potential contingency and consumable parts.................... D-5 4.0 Detailed Work Instructions ............................................................................................ D-5 4.1 Initial Testing and Inspections................................................................................. D-6 4.2 Mechanical/Electrical Operation.............................................................................. D-7 4.3 Contact Inspections and Adjustment....................................................................... D-8 4.4 Operating Mechanism Inspection............................................................................ D-9 4.5 Electrical Tests........................................................................................................ D-9 4.6 Disassembly.......................................................................................................... D-10 4.7 Inspections, Tests, Cleaning and lubrication......................................................... D-11 4.8 Reassembly .......................................................................................................... D-15 4.9 Post overhaul Inspections, Adjustments and Tests .............................................. D-17 4.10Final Breaker Assembly ....................................................................................... D-19 5.0 Determine PMT and PMT considerations ................................................................... D-19
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6.0 Feedback Mechanisms ............................................................................................... D-20 7.0 References.................................................................................................................. D-20 E WORK PACKAGE TEMPLATE – MOTOR CONTROL CENTER/LOAD CONTROL CENTER (MCC/LCC) INSPECTION AND CLEANING ........................................................................... E-1 1.0 Task Overview .............................................................................................................. E-1 1.1 Component type...................................................................................................... E-1 1.2 Equipment tag or unique equipment identifier......................................................... E-1 1.3 Scope ...................................................................................................................... E-1 1.4 Develop list of know consumable materials to be used........................................... E-1 1.5 Develop a list of know parts to be replaced ............................................................ E-1 1.6 Special tools............................................................................................................ E-1 2.0 Pre-job Brief .................................................................................................................. E-2 2.1 Evaluate potential for generation or equipment risk hazards .................................. E-2 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation ........................ E-2 2.3 Job Safety Analysis, Identifies general and specific hazards.................................. E-2 2.4 Identify permits required.......................................................................................... E-3 2.5 Identify Environmental Consideration ..................................................................... E-3 2.6 Identify Operating Experience................................................................................. E-3 2.7 Identify Clearance/Tagout Boundary....................................................................... E-3 3.0 Contingency Considerations ......................................................................................... E-3 3.1 Identify potential scope expansion and actions due to scope expansion................ E-3 3.2 Identify individuals to contact in case certain events occur..................................... E-4 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions .......................................................................................... E-4 3.4 Develop material list for potential contingency and consumable parts.................... E-4 4.0 Detailed Work Instructions ............................................................................................ E-4 4.1 Load Center Breaker Clean and Inspect................................................................. E-5 4.2 Load Center Switchgear Cleaning and Inspection: ................................................. E-8 5.0 Determine PMT and PMT considerations ................................................................... E-10 6.0 Feedback Mechanisms ............................................................................................... E-11 7.0 References.................................................................................................................. E-11 F WORK PACKAGE TEMPLATE – LIMITORQUE SMB ACTUATORS ..................................F-1 1.0 Task Overview ...............................................................................................................F-1 1.1 Component type.......................................................................................................F-1 1.2 Equipment tag or unique equipment identifier..........................................................F-1 1.3 Scope .......................................................................................................................F-1 1.4 Develop list of know consumable materials to be used............................................F-1 1.5 Develop a list of know parts to be replaced .............................................................F-2 1.6 Special tools.............................................................................................................F-2 2.0 Pre-job Brief ...................................................................................................................F-2
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2.1 Evaluate potential for generation or equipment risk hazards ...................................F-2 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation .........................F-3 2.3 Job Safety Analysis, Identifies general and specific hazards...................................F-3 2.4 Identify permits required...........................................................................................F-4 2.5 Identify Environmental Consideration ......................................................................F-4 2.6 Identify Operating Experience..................................................................................F-4 2.7 Identify Clearance/Tag out Boundary.......................................................................F-4 3.0 Contingency Considerations ..........................................................................................F-4 3.1 Identify potential scope expansion and actions due to scope expansion.................F-4 3.2 Identify individuals to contact in case certain events occur......................................F-5 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions ...........................................................................................F-5 3.4 Develop material list for potential contingency and consumable parts.....................F-5 4.0 Detailed Work Instructions .............................................................................................F-5 4.1 Preparations.............................................................................................................F-5 4.2 External Inspection of Actuator/Valve ......................................................................F-6 4.3 Limit Switch Compartment Inspection ......................................................................F-6 4.4 Torque Switch Inspection.........................................................................................F-6 4.5 Limit Switch Inspection.............................................................................................F-7 4.6 Limit Switch Gear Box Grease Inspection................................................................F-7 4.7 Motor Termination inspection...................................................................................F-8 4.8 Install Limit/Torque Switch Compartment Cover ......................................................F-8 4.9 Main Gearcase Lubrication Inspection.....................................................................F-9 4.10 Valve stem lubricant Inspection .............................................................................F-9 4.11 Motor Inspection...................................................................................................F-10 4.12 Switch Adjustments..............................................................................................F-11 4.12.1 Setting the Limit Switch ...............................................................................F-11 4.12.2 Setting the Torque Switch ...........................................................................F-12 4.12.3 SMB-000 Double Torque Switch .................................................................F-12 4.12.4 SMB-00 Torque Switch ...............................................................................F-13 4.13 Replace Stem Nut ................................................................................................F-13 4.13.1 Stem Nut Removal ......................................................................................F-13 4.13.2 Stem Nut Installation ...................................................................................F-14 5.0 Determine PMT and PMT considerations ....................................................................F-14 6.0 Feedback Mechanisms ................................................................................................F-14 7.0 References...................................................................................................................F-15 G WORK PACKAGE TEMPLATE – ELECTROSTATIC PRECIPITATOR.............................. G-1 1.0 Task Overview .............................................................................................................. G-1 1.1 Component type...................................................................................................... G-1 1.2 Equipment tag or unique equipment identifier......................................................... G-1 1.3 Scope ...................................................................................................................... G-1
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1.4 Develop list of know consumable materials to be used........................................... G-1 1.5 Develop a list of know parts to be replaced ............................................................ G-2 1.6 Special tools............................................................................................................ G-2 2.0 Pre-job Brief .................................................................................................................. G-2 2.1 Evaluate potential for generation or equipment risk hazards .................................. G-2 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation ........................ G-2 2.3 Job Safety Analysis, Identifies general and specific hazards.................................. G-2 2.4 Identify permits required.......................................................................................... G-3 2.5 Identify Environmental Consideration ..................................................................... G-3 2.6 Identify Operating Experience................................................................................. G-3 2.7 Identify Clearance/Tag out Boundary...................................................................... G-3 3.0 Contingency Considerations ......................................................................................... G-4 3.1 Identify potential scope expansion and actions due to scope expansion................ G-4 3.2 Identify individuals to contact in case certain events occur..................................... G-4 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions .......................................................................................... G-4 3.4 Develop material list for potential contingency and consumable parts.................... G-4 4.0 Detailed Work Instructions ............................................................................................ G-4 4.1 Shutdown for Maintenance ..................................................................................... G-5 4.2 Pre-maintenance checks (prior to clearance/tag out on precipitator)...................... G-5 4.3 Lower Precipitator Maintenance.............................................................................. G-8 4.4 Upper Housing (Tension Insulators and Housings, Emitter/Collector Rapper/Vibrator).......................................................................................................... G-12 4.5 Penthouse (aka. Coffin, Cans, Doghouse) Insulator compartment inspections .... G-12 4.6 Transformer/Rectifier (TR) .................................................................................... G-14 4.7 Control Cabinets (Emitter Control Cabinets, Rapper Control Cabinets) ............... G-16 5.0 Determine PMT and PMT considerations ................................................................... G-17 6.0 Feedback Mechanisms ............................................................................................... G-17 7.0 References.................................................................................................................. G-17 H WORK PACKAGE TEMPLATE – PULVERIZER OVERHAUL............................................ H-1 1.0 Task Overview .............................................................................................................. H-1 1.1 Component type...................................................................................................... H-1 1.2 Equipment tag or unique equipment identifier......................................................... H-1 1.3 Scope ...................................................................................................................... H-1 1.4 Develop list of know consumable materials to be used........................................... H-1 1.5 Develop a list of know parts to be replaced ............................................................ H-2 1.6 Special tools............................................................................................................ H-2 2.0 Pre-job Brief .................................................................................................................. H-3 2.1 Evaluate potential for generation or equipment risk hazards .................................. H-3 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation ........................ H-3 2.3 Job Safety Analysis, Identifies general and specific hazards.................................. H-3
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2.4 Identify permits required.......................................................................................... H-3 2.5 Identify Environmental Considerations.................................................................... H-3 2.6 Identify Operating Experience................................................................................. H-4 2.7 Identify Clearance/Tag out Boundary...................................................................... H-4 3.0 Contingency Considerations ......................................................................................... H-4 3.1 Identify potential scope expansion and actions due to scope expansion................ H-4 3.2 Identify individuals to contact in case certain events occur..................................... H-4 3.3 Develop material list for potential contingency and consumable parts.................... H-4 4.0 Detailed Work Instructions ............................................................................................ H-5 4.1 Prerequisites ........................................................................................................... H-5 4.2 Roll Wheel Assembly Removal ............................................................................... H-5 4.3 Grinding Ring Segment Removal and Replacement............................................... H-7 4.4 Roll Wheel Assembly Installation ............................................................................ H-9 4.4 Final Reassembly.................................................................................................. H-11 5.0 Determine PMT and PMT considerations .................................................................. H-11 6.0 Feedback Mechanisms ............................................................................................... H-11 7.0 References.................................................................................................................. H-11 I WORK PACKAGE TEMPLATE – DAMPERS .........................................................................I-1 1.0 Task Overview ................................................................................................................I-1 1.1 Component type........................................................................................................I-1 1.2 Equipment tag or unique equipment identifier...........................................................I-1 1.3 Scope ........................................................................................................................I-1 1.4 Develop list of know consumable materials to be used.............................................I-1 1.5 Develop a list of know parts to be replaced ..............................................................I-1 1.6 Special tools..............................................................................................................I-2 2.0 Pre-job Brief ....................................................................................................................I-2 2.1 Evaluate potential for generation or equipment risk hazards ....................................I-2 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation ..........................I-2 2.3 Job Safety Analysis, Identifies general and specific hazards....................................I-2 2.4 Identify permits required............................................................................................I-2 2.5 Identify Environmental Consideration .......................................................................I-3 2.6 Identify Operating Experience...................................................................................I-3 2.7 Identify Clearance/Tag out Boundary........................................................................I-3 3.0 Contingency Considerations ...........................................................................................I-3 3.1 Identify potential scope expansion and actions due to scope expansion..................I-3 3.2 Identify individuals to contact in case certain events occur.......................................I-3 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions ............................................................................................I-3 3.4 Develop material list for potential contingency and consumable parts......................I-4 4.0 Detailed Work Instructions ..............................................................................................I-4 4.1 Inlet Damper Clean/Inspection..................................................................................I-4
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4.2 Damper Bearings ......................................................................................................I-6 4.3 Lubrication.................................................................................................................I-6 4.4 Reassembly ..............................................................................................................I-7 5.0 Determine PMT and PMT considerations .......................................................................I-7 6.0 Feedback Mechanisms ...................................................................................................I-7 7.0 References......................................................................................................................I-8 J WORK PACKAGE TEMPLATE – CENTRIFUGAL PUMP (PROCESS, 3196) .....................J-1 1.0 Task Overview ............................................................................................................... J-1 1.1 Component type....................................................................................................... J-1 1.2 Equipment tag or unique equipment identifier.......................................................... J-1 1.3 Scope ....................................................................................................................... J-1 1.4 Develop list of know consumable materials to be used............................................ J-1 1.5 Develop a list of know parts to be replaced ............................................................. J-2 1.6 Special tools............................................................................................................. J-2 2.0 Pre-job Brief ................................................................................................................... J-2 2.1 Evaluate potential for generation or equipment risk hazards ................................... J-2 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation ......................... J-2 2.3 Job Safety Analysis, Identifies general and specific hazards................................... J-3 2.4 Identify permits required........................................................................................... J-3 2.5 Identify Environmental Consideration ...................................................................... J-3 2.6 Identify Operating Experience.................................................................................. J-3 2.7 Identify Clearance/Tag out Boundary....................................................................... J-3 3.0 Contingency Considerations .......................................................................................... J-4 3.1 Identify potential scope expansion and actions due to scope expansion................. J-4 3.2 Identify individuals to contact in case certain events occur...................................... J-4 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions ........................................................................................... J-4 3.4 Develop material list for potential contingency and consumable parts..................... J-4 4.0 Detailed Work Instructions ............................................................................................. J-4 4.1 Preparations............................................................................................................. J-5 4.2 Preparation for pump removal.................................................................................. J-5 4.3 Pump Disassembly .................................................................................................. J-6 4.4 Pump Inspection ...................................................................................................... J-7 4.5 Pump Reassembly ................................................................................................... J-7 4.6 Pump Installation.................................................................................................... J-11 4.7 Final Pump Assembly ............................................................................................ J-14 5.0 Determine PMT and PMT considerations .................................................................... J-15 6.0 Feedback Mechanisms ................................................................................................ J-16 7.0 References................................................................................................................... J-16 K WORK PACKAGE TEMPLATE – STEAM TRAPS .............................................................. K-1
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1.0 Task Overview .............................................................................................................. K-1 1.1 Component type...................................................................................................... K-1 1.2 Equipment tag or unique equipment identifier......................................................... K-1 1.3 Scope ...................................................................................................................... K-1 1.4 Develop list of know consumable materials to be used........................................... K-1 1.5 Develop a list of know parts to be replaced ............................................................ K-2 1.6 Special tools............................................................................................................ K-2 2.0 Pre-job Brief .................................................................................................................. K-2 2.1 Evaluate potential for generation or equipment risk hazards .................................. K-2 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation ........................ K-2 2.3 Job Safety Analysis, Identifies general and specific hazards.................................. K-2 2.4 Identify permits required.......................................................................................... K-3 2.5 Identify Environmental Consideration ..................................................................... K-3 2.6 Identify Operating Experience................................................................................. K-3 2.7 Identify Clearance/Tag out Boundary...................................................................... K-3 3.0 Contingency Considerations ......................................................................................... K-3 3.1 Identify potential scope expansion and actions due to scope expansion................ K-3 3.2 Identify individuals to contact in case certain events occur..................................... K-3 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions .......................................................................................... K-4 3.4 Develop material list for potential contingency and consumable parts.................... K-4 4.0 Detailed Work Instructions ............................................................................................ K-4 4.1 Testing Steam Traps............................................................................................... K-4 4.2 Steam Trap Maintenance........................................................................................ K-6 4.2.1 Thermodynamic Steam Trap................................................................................ K-7 4.2.2 Ball Float Steam Trap .......................................................................................... K-7 4.2.3 Balance Pressure Steam Trap ............................................................................. K-8 4.2.4 Thermostatic Steam Trap..................................................................................... K-9 4.2.5 Inverted Bucket Steam Trap ................................................................................ K-9 4.2.6 Liquid Expansion Steam Trap ............................................................................ K-10 5.0 Determine PMT and PMT considerations ................................................................... K-10 6.0 Feedback Mechanisms ............................................................................................... K-11 7.0 References.................................................................................................................. K-11 L WORK PACKAGE TEMPLATE – GATE AND GLOBE VALVES .........................................L-1 1.0 Task Overview ...............................................................................................................L-1 1.1 Component type.......................................................................................................L-1 1.2 Equipment tag or unique equipment identifier..........................................................L-1 1.3 Scope .......................................................................................................................L-1 1.4 Develop list of know consumable materials to be used............................................L-1 1.5 Develop a list of know parts to be replaced .............................................................L-1 1.6 Special tools.............................................................................................................L-2
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2.0 Pre-job Brief ...................................................................................................................L-2 2.1 Evaluate potential for generation or equipment risk hazards ...................................L-2 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation .........................L-2 2.3 Job Safety Analysis, Identifies general and specific hazards...................................L-2 2.4 Identify permits required...........................................................................................L-2 2.5 Identify Environmental Consideration ......................................................................L-3 2.6 Identify Operating Experience..................................................................................L-3 2.7 Identify Clearance/Tag out Boundary.......................................................................L-3 3.0 Contingency Considerations ..........................................................................................L-3 3.1 Identify potential scope expansion and actions due to scope expansion.................L-3 3.2 Identify individuals to contact in case certain events occur......................................L-3 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions ...........................................................................................L-4 3.4 Develop material list for potential contingency and consumable parts.....................L-4 4.0 Detailed Work Instructions .............................................................................................L-4 4.1 Disassembly.............................................................................................................L-4 4.2 Inspections ...............................................................................................................L-5 4.3 Valve repairs ............................................................................................................L-6 4.4 Reassembly .............................................................................................................L-7 5.0 Determine PMT and PMT considerations ......................................................................L-7 6.0 Feedback Mechanisms ..................................................................................................L-7 7.0 References.....................................................................................................................L-8 M WORK PACKAGE TEMPLATE – MULTI-STAGE VERTICAL PUMP ................................M-1 1.0 Task Overview ..............................................................................................................M-1 1.1 Component type......................................................................................................M-1 1.2 Equipment tag or unique equipment identifier.........................................................M-1 1.3 Scope ......................................................................................................................M-1 1.4 Develop list of know consumable materials to be used...........................................M-1 1.5 Develop a list of know parts to be replaced ............................................................M-2 1.6 Special tools............................................................................................................M-2 2.0 Pre-job Brief ..................................................................................................................M-2 2.1 Evaluate potential for generation or equipment risk hazards ..................................M-2 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation ........................M-3 2.3 Job Safety Analysis, Identifies general and specific hazards..................................M-3 2.4 Identify permits required..........................................................................................M-3 2.5 Identify Environmental Consideration .....................................................................M-3 2.6 Identify Operating Experience.................................................................................M-3 2.7 Identify Clearance/Tag out Boundary......................................................................M-4 3.0 Contingency Considerations .........................................................................................M-4 3.1 Identify potential scope expansion and actions due to scope expansion................M-4 3.2 Identify individuals to contact in case certain events occur.....................................M-4
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3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions ..........................................................................................M-4 3.4 Develop material list for potential contingency and consumable parts....................M-4 4.0 Detailed Work Instructions ............................................................................................M-5 4.1 Preparations............................................................................................................M-5 4.2 Motor Removal........................................................................................................M-5 4.3 Disassembly and removal of discharge head .........................................................M-6 4.4 Disassembly of columns and line shafts .................................................................M-6 4.5 Disassembly or Bottom column section ..................................................................M-7 4.6 Impeller Bowl disassembly ......................................................................................M-7 4.7 Inspection of Pump components .............................................................................M-8 4.8 Pump Assembly ....................................................................................................M-10 4.8.1 Assembly of pump bowls..............................................................................M-10 4.8.2 Assembly of lower line shaft and column to pump assembly .......................M-11 4.8.3 Installation of lower pump assembly in pump well .......................................M-11 4.8.4 Installation of line shafts and columns..........................................................M-11 4.8.5 Installation of discharge head.......................................................................M-12 4.8.6 Final Assembly .............................................................................................M-12 5.0 Determine PMT and PMT considerations ...................................................................M-12 6.0 Feedback Mechanisms ...............................................................................................M-13 7.0 References..................................................................................................................M-13 N LISTING OF KEY INFORMATION ....................................................................................... N-1 N.1 Key O&M Cost Points ............................................................................................. N-1 N.2 Key Human Performance Points ............................................................................ N-2 N.3 Key Technical Points .............................................................................................. N-3
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1 INTRODUCTION 1.1 Purpose and Scope The purpose of this report is to provide fossil plant maintenance organizations with some generic work package templates. These templates can then be used as guides to develop site specific work packages. The templates contain information that can be used by maintenance organizations no matter what the current level of work planning or work package development may exist. Maintenance organizations that have processes in place can find information that will enhance their current processes. For maintenance organizations that may have less structures processes the templates will provide a firm foundation for developing work packages. The templates cover a wide range of equipment types as well as a variety of maintenance activities including inspections, minor repairs and overhauls. Work packages can increase the efficient use of resources, improve overall maintenance and equipment reliability, increase overall productivity and enhance human performance error reduction. 1.2 Background Currently there is little to no means to share lessons learned from maintenance activities among fossil utilities and to benefit from the efficiencies learned from using enhanced/optimized work packages. In many cases, work packages are repeatedly prepared for equipment that is common among most fossil power plants. A compilation of work package templates that provides information for the development of specific work orders will improve the efficiency and technical adequacy or work packages. These templates will be provided for common maintenance activities by component and in a standardized format. 1.3 Report Structure and Overview Section 2 of the report provides basic work package related information. Information includes the benefits that can be realized from the use of work packages and how to use work packages. Section 3 presents the format of a generic work packages and discusses the contents of each section. Section 4 provides a list of key references used in developing many of the work package templates. There are numerous EPRI products listed that provide greater detail on the operation and maintenance of key plant equipment. The appendices provide numerous work package templates on a wide range of plant equipment and various levels of maintenance activities (E.g. inspections, minor repairs, and overhauls).
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Figure 1-1 Work Package Template Overview
1.4 Glossary of Terms and Acronyms 1.4.1 Industry Definitions and Nomenclature Air Circuit Breaker – A circuit breaker whose primary circuit interrupts current in air verses vacuum, oil or gas. Air load - This term refers to energizing the ESP during an outage period at ambient temperatures. The object is to verify the electrical integrity of the bus section, to obtain electrical readings of voltage and current, and to determine whether spark over occurs before reaching a specific limit of the TR set rating. The advantage of this type of measurement is to relate the internal integrity of the ESP bus sections to one another as to electrode damage or extent of ash buildup. Alignment - A condition where the axis or center lines of two shafts are in line or coaxial. Antipump device – After an opening operation, this device prevents the reclosing of the circuit breaker as long as the device that initiated the opening is maintained in the position for opening.
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Anti-sway insulator - These insulators are used to prevent the bottom, HV frames, which position and retain the discharge electrodes, from swinging or drifting out of alignment. The insulators are either a ceramic bar or a shaft type and are usually secured to the hopper wall. Some designs connect directly between the collecting plates and the lower, HV frames. Arc Chute – A confined space or passageway, lined with an arc resistant material, into or through which an arc is directed to extinction. Arcing contacts – The contacts of the circuit breaker on which the arc is drawn after the main and intermediate (if used) contacts have parted. Auxiliaries – Devices which perform secondary functions as adjuncts or refinements to the primary function of the circuit breaker. Auxiliary Switch – A switch which is mechanically operated by the operating mechanism for indication, interlocks or other control functions and reflects the open or closed status of the breaker. Bell Alarm – An alarm that features one normally open and one normally closed contact activated by the auto-trip indicator. Brinelled bearing - A brinelled bearing is one in which a dent has been formed in one of the races by a ball. Bus – A conductor or group of conductors that serve as common connection for two or more circuits. Centrifugal Fan – A fan rotor or wheel within a scroll-type housing and including driving mechanism supports for either belt drive or direct connection. Classifier, dynamic - A rotating vane assembly for the separation of coal particles. Classifier, stationary - A combination of a vane and cone section designed to maintain and control the desired fineness of the coal leaving the mill. Closing Spring Charging Motor – A motor that is energized automatically by internal limit switches to charge the closing springs electrically. Coal pulverizer - A machine that reduces the size of coal particles, dries the coal, classifies the coal, and transports the coal to the boiler piping. Also called a coal mill. Cold-side ESP - An ESP which is installed downstream of the air heaters. Collecting surface - Is the term for the sheet metal collector plate that serves as the point of deposition for the particulate that is negatively charged within the gas passage of the ESP. Collecting surface plate design differs between manufacturers, but all are secured to the shell of the ESP at ground potential and serve as the positive anode of the gas passage. Component – A generic technical part. Many components make up equipment. Hierarchy is: parts make components, components make equipment, and equipment makes systems. Contacts – Two conducting parts that interact to make or break a circuit.
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Corrective Maintenance – All maintenance performed to correct a breakdown or failure. Critical speed – The speed of a rotating system that corresponds to a natural frequency of the system. Damper – A device used to vary the volume of air passing through an air outlet, air inlet, or duct. Declutch Lever- A lever that is operated to allow manual operation of the Limitorque actuator using the handwheel. The declutch lever will automatically disengage upon operation of motor. Discharge electrode - Refers to the HV component that ionizes the process gases and creates the electric field. It is shaped to provide a corona discharge when the impressed voltage breaks the gas down at the electrode surface. This breakdown of the gas creates corona tufts on the discharge surface. Typically, voltage applied to the discharge electrode is of negative polarity. In many weighted-wire designs, the discharge electrode is a smooth round wire slightly larger than 0.1 in. (2.54 mm) in diameter. Barbed wire is also frequently used in part, or all of the ESP, to enhance corona characteristics. Discharge Electrodes of the rigid and rigid frame or mast variety are also widely available. They can vary widely in style and shape. Drawout feature – An option available on circuit breakers which allows the circuit breaker to be disconnected and r4emoved from the switchboard without de-energizing the switchboard. ESP - electrostatic precipitator (ESP) - a facility that removes fly ash from the flue gas by producing an electric charge on the fly ash and collecting it electrostatically. Fan – Any device that produces a current of air by the movement of a broad surface can be called a fan. There are several types: Centrifugal, Axial, Propeller, Tube axial, and Vane axial. Fans are also called compressors, ventilators, exhausters, and blowers. Finger Tight - Refers to the tightening of a fastener without the aid of a wrench. Four-train geared limit switch - The rotor-type, four-train geared limit switch employs four rotary drum switches. Each rotary drum switch contains four contacts. When the rotor is properly set to trip at the desired position, two of these contacts open electric circuits and two of the contacts close electric circuits. One rotor is set to trip at the full open position of the valve, and one rotor is set to trip at the full close position of the valve. The other two rotors are set at some intermediate position depending on the application. Frame Size – The maximum continuous current rating (In amps) of a circuit breaker for all parts except the coils of the direct acting overcurrent trip device. Gas distribution devices - Internal elements in the transition or ductwork to produce the desired velocity contour at the inlet and outlet face of the precipitator (for example, turning vanes or perforated plates). Hoppers - Hoppers located at the bottom of the precipitator casing and are used to collect the material that has been collected and that falls off of the internal components that are cleaned. The typical shape is pyramidal; with the sides of each hopper being steep sloped. The outlet opening is sized so that fly ash may be easily removed by an ash removal system. Baffles are usually placed in the hoppers; they extend below the dust level to minimize undesirable gas leakage
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below the collection plates. Typically, hoppers are equipped with level detectors to alarm high levels and hopper heaters that are used to reduce corrosion and to keep the material fluidized. Hoppers are also equipped with access doors, strike plates for manually rapping the hopper walls, and poke holes to unclog the hopper outlets. Housing – The housing for a fan is the stationary element that guides the air or gas before and after the impeller. A housing can also be called a casing, a stator, a scroll, a panel, a ring, or a volute. For fans, housing, casing, and stator are the preferred general terms. Inspection – Any activity performed to find a failure or breakdown. Intermediate contacts – Contacts in the main circuit which part after the main contacts have parted and before the arcing contacts have parted. Isolation Damper – A damper installed in a system that is capable of stopping or diverting flow from one portion of the system to another. Journal bearing – A cylindrical bearing. Key-interlock system - A system of locks that prevents opening the ESP access doors while the precipitator is energized. Long-Time Delay Trip Element – The element of a direct acting overcurrent trip device that functions with a purposely delayed action (typically 2-1000 seconds) on an overcurrent condition. Main Contacts – Contacts that carry all or most of the current of the main circuit. Operating Mechanism – The part of the mechanism that actuates all the main circuit contacts of the switching device either directly or by the use of pole-unit mechanisms. Overcurrent Protection – A form of protection that operates when the current in the main circuit exceeds a predetermined value. Penthouse - A weatherproof, gas-tight enclosure over the precipitator to contain the HV insulators. Pre-Job Brief – An interactive dialogue between those involved in the work to ensure that all understand the scope of what is to be accomplished, procedural steps, roles and responsibilities, and hazards and controls that provide a heightened level of awareness of significant aspects of the task. Pulley –A wheel attached to a shaft, which carries a belt or chain. See sheave. Rappers (Collecting surfaces) - These are devices, generally located at the top of the ESP or bottom of the collecting plates, which periodically impart a shock to the collecting surfaces to help dislodge the collected material into the hopper system. The final collection efficiency of the precipitator is often determined by how well this process is conducted. The object is to dislodge the material from the collector surface in small clumps or patches without building excessive dust layer thicknesses. This is a complex part of precipitation, but it is more important to know that reliability of rapper operation holds priority over timing, impact force, and other aspects of this system.
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Rappers (High voltage) - These rapper devices impart a vibration or shock to the HV frame supporting the discharge electrodes. The object is to keep the buildups on these electrodes from affecting the corona discharge pattern. The discharge electrodes will generally exhibit irregular coatings of various size and shape. Whether the buildups observed during outage inspections are detrimental can usually be determined by an analysis of electrical readings during periods of operation. It is usually better to operate with some buildup than employ excessive rapping forces that can result in failure of discharge electrodes. Reversing Starter - The reversing starter electrically changes the operation of the electric motor from one direction of rotation to the other. The starter consists of two contactors mounted on a common base and mechanically interlocked. Safety grounding device - A device for physically grounding the HV system prior to personnel entering the precipitator. The most common type consists of a conductor, one end of which is grounded to the casing, the other attached to the HV voltage system using an insulated operating lever. Sheave - A wheel attached to a shaft, which carries a belt or chain. See pulley. Short-time delay trip element – A direct-acting trip device that functions with a purposely delayed action (typically 0.07 – 1 second) on an overcurrent condition. Shunt Trip Device – A circuit breaker attachment that utilizes a solenoid to rotate the trip shaft to open (trip) the circuit breaker. The shunt trip device is used to open an electrically operated breaker under normal conditions. Sleeve bearing – A bearing that carries lubricant for the shaft rotating within it. Often used synonymously with Journal bearing. Snug Tight - Refers to the tightening of a fastener, or a group of fasteners, in such a manner that brings faces together uniformly and ensures that the fastener(s) cannot be loosened by hand. When fastener preload values are required, subsequent torquing will be necessary. Test Position – The position where the primary disconnecting devices of the removable element are separated by a safe distance from those in the housing. Some or all of the secondary disconnecting devices are in operating contact. Torque Switch – A device designed to protect the actuator in open and close directions. TR set - Is the term for the HV transformer and rectifier that provides the electrical energy for a given precipitator area. These components involve a specially wound transformer that supplies a RMS secondary voltage sized on the basis of gas passage spacing and discharge electrode design. An RMS secondary voltage of about 53,500 volts ac (45 kV dc average) is utilized for the 9 in. (228.6 mm) wide gas passage of most weighted-wire precipitators; 77,300 volts ac (65 kV dc average) for most of the 12 in. (304.8 mm) wide gas passage of rigid electrode precipitators. Two-trained geared limit switch - The rotor-type, two-train geared limit switch employs two rotary drum switches. Each rotary drum switch contains four contacts. When the rotor is properly set to trip at the desired position, two of these contacts open electric circuits and two of the
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contacts close electric circuits. One rotor is normally set to trip at the full open position of the valve, and the other rotor is normally set to trip at the full close position of the valve. Undervoltage Trip (Release) – A release that operates when the voltage of the main circuit is equal to or less than the release setting. V-I curve - Usually refers to a plot of secondary voltage versus secondary current for a single TR set in which the shape of the plotted curve might indicate a number of internal operating characteristics of the precipitator. An important part of these measurements is the indicated voltage at the threshold of corona current. While normally obtained during air load, these curves sometimes can be developed during operating periods. Work Instruction – Instructions for performance of the work to be accomplished, the level of detail of which is dependent on the assigned planning level. When applicable, approved procedures may be referenced and may suffice as work instructions. Work Package – A compilation of documents including the work order, work instructions, and any other supporting material (that is, drawings, vendor manuals, weld process sheets, operating experience, safety analysis, permits, for example). Wrench Tight - Refers to using "skill of the craft" to tighten a fastener with a hand wrench to a degree of tightness that is acceptable to the craftsman with no further verification. 1.4.2 Acronyms CAP – Corrective Action Program ESP - Electrostatic Precipitator FME – Foreign Material Exclusion ICS – Industrial Control and Systems ID – Inside Diameter LCC – Load Control Center MCC – Motor Control Center MSDS – Material Safety Data Sheet NEMA – National Electrical Manufactures Association NFPA – National Fire Protection Association OD – Outside Diameter OSHA – Occupational Health and Safety Administration
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1.5 Key Points Throughout this guide, key information is summarized in Key Points. Key Points are bold lettered boxes that highlight information covered in the text. The primary intent of a Key Point is to emphasize information that will allow individuals to act for the benefit of their plant. EPRI personnel who reviewed and prepared this guide selected the information included in these Key Points. The Key Points are organized into three categories: Human Performance, O&M Costs, and Technical. Each category has an identifying icon to draw attention to it when quickly reviewing the guide. The Key Points are shown in the following way: Key O&M Cost Point Emphasizes information that will result in reduced purchase, operating, or maintenance costs. Key Human Performance Point Denotes information that requires personnel action or consideration in order to prevent injury or damage or ease completion of the task. Key Technical Point Targets information that will lead to improved equipment reliability.
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2 WORK PACKAGE TEMPLATES 2.1 Introduction Maintenance is the most critical function when it pertains to product output, quality and safety. An effective maintenance organization possesses the ability to adapt to a dynamic, quick changing environment. Today’s environment is a competitive one that is ever changing and expanding at an increasing rate to keep up with the demands of electrical generation. It is not enough, nor is it an effective strategy to meet competitive challenge through doing less. This measure may be the quickest but it is not necessarily the wisest. To best meet the competitive challenge the continually improving maintenance organization is finding ways to work smarter. Working smarter means being ready for the expected and the unexpected. Taking advantage of new technologies has been one method that has proven to be successful. Technology has lead to more efficient and reliable equipment, but with the increase in efficiency and reliability has come complexity. With complexity there is the growing need for better training and better resources for the maintenance craftsman to be able to perform their work. One of the resources that can aid the craftsman in this area is the work package. Key O&M Cost Point To best meet the competitive challenge the continually improving maintenance organization is finding ways to work smarter. Working smarter means being ready for the expected and the unexpected.
With the complexity of plant equipment it is no longer feasible to rely on the memory of the craftsman to ensure the inspections and corrective maintenance are performed correctly, efficiently and safely. The craftsman requires guidance. Without this guidance a task may take longer to perform, it may be performed incorrectly or incompletely. All available work may not be performed while the equipment is available for maintenance. These inefficiencies may lead to increased equipment unavailability and downtime during the maintenance activities as well as increase the likelihood of reduced reliability due to poor maintenance or missed opportunities to perform required maintenance. Work packages provide the maintenance craftsman with the level of detail necessary to perform a work activity correctly, efficiently and safely. In addition, work packages provide an opportunity to incorporate controls and barriers to mitigate the potential for error or to mitigate the consequences of error. If a maintenance task is to be performed correctly it must contain sufficient detail. The amount of detail required will different from one maintenance organization to another based on many factors. (E.g. Training, experience and skill level of craftsman, resources, etc) Although the level of detail may vary to basic content of the work package from one facility to another to another should
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possess some basic similarities. (E.g. Scope of work to be performed, parts required, tools required, proper equipment clearance, safety and error free considerations, step by step guidance on how the work is to be accomplished) Key Human Performance Point Work packages provide the maintenance craftsman with the level of detail necessary to perform a work activity correctly, efficiently and safely.
If the maintenance organization finds itself in a position of constantly reacting to emergencies and unplanned shutdowns, spending significant amounts of time searching for spare parts, lacking the proper skills and tools for the craftsman or always feeling rushed to perform repairs at the sacrifice of quality, then the maintenance organization is functioning in a “fire-fighting” mode. The use of developed work package templates allows the maintenance organization to move from the fire-fighting mode of performing work to an operational mode that is structured and proactive. The work package will serve as the backbone of a proactive maintenance organization. It will provide the how to for work execution, information input to a variety of maintenance functions and a valuable source of feedback for continuous improvement. The work package will be the primary tool used to manage all aspects of the maintenance activity: labor resources, parts, human performance, a measure of organizational effectiveness, etc. The labor resource is one of the largest and expensive within the maintenance department. If the labor resource is not being utilized effectively and efficiently, a significant amount of money is being wasted. Key Technical Point The use of developed work package templates allows the maintenance organization to move from the fire-fighting mode of performing work to an operational mode that is structured and proactive.
Key O&M Cost Point The labor resource is one of the largest and expensive within the maintenance department. If the labor resource is not being utilized effectively and efficiently, a significant amount of money is being wasted. When equipment inspections are required a pre-developed package can be retrieved and used to perform the inspection. It can be easily modified accommodate the current needs. The majority of the preparation planning was done far in advance. The major activity left, other than the work itself, is to pull together the resources defined within the work package. The same applies for corrective maintenance and overhauls. In the case of corrective maintenance it is very probable that an overhaul work package template could be modified to meet the particular needs of the corrective maintenance far more efficiently than starting from scratch.
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The work package is the communications vehicle for the maintenance organization to perform its overall function. Not only does it provide the craftsman with the necessary instructions on how to perform the work but it also provides the acceptable maintenance standards and behaviors expected during the performance of the work When the work package is properly implemented it helps ensure that the maintenance is performed consistently and correctly, regardless of which craftsman performs the work 2.2 Benefits of Work Package Templates The first impression may be that work package templates will take resources from other critical maintenance functions with very little benefit in return. Like most new processes the initial effort may appear overwhelming. The issues facing the organization today appear to overshadow the longer term priorities. The work package template will provide the maintenance organization with a more accurate and efficient tool for the scheduling and execution of maintenance activities. Works order templates contain all planned information including parts, resources requirements, work instructions, etc. Work package templates can take a lot of the work out of the planning function so that it can be focused more on other improvements. Following are some of the benefits that can be realized from a system of work package templates. 1. The maintenance organization will be more responsive to meeting emerging work needs. It will move from a fire-fighting mode to a mode that is more structured and proactive. 2. Provides step-by-step sequence of work instructions. This includes NOTE’s and CAUTION’s that can protect both equipment and personnel as well as provide additional information to enhance the effectiveness of the maintenance activity. 3. Templates can be readily modified to suit particular maintenance activities. They can be used in their entirety or in part based on the particular needs. 4. Can provide improvement in safe working practices. 5. Estimation variances, additional tips or instructions, improving the safe working practices and reviewing the stores re-credits can offer areas of improving work order templates. 6. Templates can be used as training tools. 7. Templates can also be used to store trouble shooting guides for specific symptoms/fault modes. 8. Work packages can assist the maintenance craftsman in reducing errors. Key O&M Cost Point The work package template will provide the maintenance organization with a more accurate and efficient tool for the scheduling and execution of maintenance activities.
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2.3 Work Package Templates The work package templates in this report are generic. They were designed, in most cases, to encompass a wide range or work tasks required on a particular type of equipment regardless of the manufacturer of the equipment. There are a few exceptions such as Limitorque actuators and Gould 3196 process pumps. Due to their wide spread use in the industry more detail is provided. Tolerances and specifications are left to the specific site. Also due to differences in design some templates reference a particular design type. For example a coal pulverizer may use one of many mechanisms to perform its function. (E.g. roll wheel verses a tube or ball mill). Although their function is identical the inspections and overhauls of the different types would be different. It is difficult to create a generic work package template. In the case of low voltage air operated circuit breakers the task is more feasible. Circuit breaker design is similar enough between manufacturers to allow for a work package template to be created. All breakers have a frame, operating mechanism, contacts and protective devices. There will of course be differences in certain devices between manufacturers. 2.4 How to Use the Templates The degree of formalization of work processes between fossil plants will differ. Some plants may possess very detailed and formalized procedures for the conduct of maintenance activities. At the other end of the spectrum will be plants that develop and redevelop work instructions only as they are needed upon equipment failure. Of course there will be a wide range of processes used between these two extremes. Regardless of the level of sophistication of the work process being used by any given maintenance organization, the work package templates contained in this report will prove to be of value. In facilities where more formalized processes exist, the work package templates may provide alternative methods, human performance considerations, notes or cautions or other information that will be of benefit to the way maintenance is performed. In less formalized processes the work package templates will provide a foundation for the development of specific work packages for the templates provided as well as a process that can be used to develop specific work packages on other pieces of equipment. In organizations with more formalized processes, either procedures or work packages, the templates may be used to enhance existing products. Key considerations during the review should include: 1. Personnel safety and equipment protection – Throughout the templates there are notes and cautions used to raise awareness to potential personnel safety issues or to maintenance issues that could affect the reliability of the maintenance being performed. 2. Pre-job brief – In this section there are items that may be considered when performing pre-job briefs prior to maintenance activities. The items in this section are directly applicable to the type of work being performed and may assist in the prevention of errors during maintenance. 3. Inspection activities – When items are required to be inspected most procedure tell what is to be expected. The templates provide what to inspect and in addition provide guidance to the craftsman of what the inspection should entail. 2-4
In organizations that do not possess formalized procedures or work packages for equipment inspections, repairs and overhauls, the templates will provide a solid foundation from which facility specific work packages can be developed. There will be short term costs associated with the development of the specific work packages but the long term gains will outweigh these costs. Key O&M Cost Point There will be short term costs associated with the development of the specific work packages but the long term gains will outweigh these costs. Because the work packages templates are generic it is recommended that during specific work package development that appropriate references be used. References include vendor technical manuals, drawings and other engineering documents. For example there may be tolerance criteria for a measurement taken on a piece of equipment. Appropriate acceptance criteria should be obtained from the vendor technical manual. Another example of the generic nature of the work packages would be equipment alignment. The work package will appropriately call for an alignment but it is left at the discretion of the particular facility as to how the alignment is to be accomplished. Each plant will be different based on the method that is used in their training or the technology available (E.g. laser alignment, double-dial) 2.5 Planning Walkdowns An important step in the planning process is the planning walkdown. This is an important step in developing the finalized work package for the maintenance activity. The planning walkdown is essential for the development of pre-job considerations and contingencies. Each facility will differ with respect to where equipment is located, accessibility to equipment (E.g. work platforms), laydown areas, interferences (E.g. struts, pipe supports, hangers), rigging supports, etc. The effort taken to perform a thorough walkdown of the work area will enhance the work package and enable it to be used more effectively. It will help expedite repairs and minimize equipment unavailability. The thoroughness and consistency of walkdowns can be improved through the use of a checklist. During the walkdown considerations should typically include: 1. Does the work instruction encompass the scope of work to be done? Have new items been identified that should increase the scope? Conversely are the items that should be removed from the scope of the work package? 2. Will the work impact other equipment in the area? Will operating equipment in the work area require special considerations with respect to potential impact on the operating equipment or personnel safety? This is of special note when the maintenance is being performed with the unit on line. 3. Are there interferences that must be removed to support the maintenance activity? Can they be removed safely? Will their removal impact operating equipment? Pipes? Supports? Hangers? Insulation? Etc.
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4. Is there sufficient space in the work area to carry out the maintenance safely? Is there room for scaffolding, ladders, laydown areas, proper rigging sites, forklift access, cranes, etc.? 5. Are there physical limitations to performing the work safely? 6. What is the status of environmental conditions at the work site? Lighting? Temperature concerns? Hot pipes? Rotating machinery? Etc. 7. Are there any personnel safety considerations? 8. What special permits may be required? Confined Workspace? Transient combustible storage? Etc. 9. Are facilities available? Electrical, water, air, phones? 10. It also provides an opportunity to validate materials and special tooling needs. Key Human Performance Point The planning walkdown is essential for the development of pre-job considerations and contingencies. The results of the walkdown should be incorporated into the work package. During the walkdown there are tools that should be available to the planner to achieve the greatest benefits from the walkdown. These include: 1. Digital voice recorder. It is much easier than taking written field notes. 2. Small digital camera. These are of benefit when sitting down and completing the work package. They also make excellent reference materials during pre-job briefs. 3. Measuring tape. 4. Strong flashlight 5. Laser pointer. (Excellent for pointing out details in pictures, E.g. leak identification) 6. Notebook.
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3 WORK PACKAGE TEMPLATE FORMAT 3.1 Task Overview
Figure 3-1 Work Package Development - Task Overview
This section of the work package provides general information regarding the task. The section consists of the following sub-sections. 1. Component type – describes the type of equipment that is to be worked. 2. Equipment tag or unique identifier – describes the exact piece of equipment to be worked indicated by a unique equipment identifier. (e.g. 1A Boiler Feedwater Pump, Breaker 42317 1A Boiler Feedwater Pump) 3. Location of Equipment – Provide a brief description of where the equipment is located. (E.g. building, floor elevation, room, etc) Proving a drawing of the equipments location and a picture of the equipment should be included in the package if available. 3-1
4. Scope – describes in general the type of work to be performed on the piece of equipment. (E.g. Inspection, test, repair, overhaul, etc) 5. List of known consumables – a list of consumable products (e.g. rags, cleaning solvents, oil, grease, etc) that will be used during performance of work. 6. List of know parts to be replaced – provides a list of parts that will be used during the performance of the work based on the scope of work described. Each piece of equipment should have a Bill of Materials (BOM). 7. Tools/Special tools – provides a list of tools that will be required to perform the scope of work properly and safely. List includes typical journeyman’s tools, safety equipment and specialty tools required to perform the scope of work. 8. Craftsman skills required – The types of craftsman to be used during the maintenance activity should be identified. 3.2 Pre-Job Considerations
Figure 3-2 Work Package Development – Pre-job Considerations
This section of the work package provides a significant amount of information necessary to ensure equipment, personnel and the environment are not impacted as a result of the maintenance activity. The section consists of the following subsections. 3-2
1. Evaluate potential for generation or equipment risk hazards – This section provides considerations concerning the effect the maintenance may have on the plant. This may include precautions for working a piece of equipment on line, effects on system lineups, precautions that should be taken during the course of maintenance to preclude potential damage to equipment being worked, etc. Consideration should also be given to equipment in the immediate vicinity of the work location. Work activities should be evaluated to determine if the potential exist to inadvertently affect equipment in the area. (E.g. scaffold was built with a scaffold bar running through the handwheel of a piece of nearby equipment) 2. Identify Foreign Material Exclusion (FME) potential and mitigation – Foreign material introduced into a piece of equipment or system during maintenance can have severe impact on plant operations. (E.g. platform board was left in condenser waterbox following waterbox cleaning) This section provides information related to certain tasks during maintenance where foreign material could be introduced as well as measures that should be taken during maintenance to prelude the introduction of foreign material into the equipment being worked. 3. Job Safety Analysis – Maintenance tasks can represent hazards to both equipment and personnel. This section provides information that should be considered with regard to performing a job safely and correctly to minimize the potential for causing injury to personnel or equipment damage related to the maintenance being performed. 4. Identify permits required – Many maintenance activities may prove hazardous to the equipment, personnel or the environment. To protect these assets administrative programs have been developed. Typical permits that may be required during maintenance include; Equipment Clearance Order/Tag Out, Confined Space Entry, Hot Work Permit, Transient Combustible Control, Chemical Traffic Control/MSDS. 5. Identify environmental considerations – This section is concerned with the identification of environmental hazards that may be imposed on the worker (e.g. temperature, lighting, lethal gases, chemicals, combustible atmospheres, etc) as well as mitigation of the release of hazardous substances used during maintenance to the environment. 6. Review operating experience - Review any relevant plant specific or industry related operating experience applicable to the work being performed. The review of operating experience can help reduce risk to both personnel and equipment by learning from past mistakes or problems that have been encounter in the industry or at the given facility. Operations experience can be drawn from various sources including: a. Experienced personnel proving experiences and expertise, especially during prejob briefs b. From on-site experiences, especially the Corrective Action Program c. From previous performance of work orders d. Experience from other utility experiences
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e. Vendor bulletins f. Identify Clearance/Tag Out Boundary – This section provides general information with respect to how a piece of equipment may be removed from service to ensure that both personnel injury and equipment damage is prevented. This is provided as general information ONLY. Each site, due to differences in design, must use its knowledge of the system along with applicable drawings (piping, wiring, vendor, etc) to ensure that equipment is properly isolated and placed in a condition such that maintenance can be performed safely. Key Human Performance Point The review of operating experience can help reduce risk to both personnel and equipment by learning from past mistakes or problems that have been encounter in the industry or at the given facility. 3.3 Contingency Considerations
Figure 3-3 Work Package Development – Contingency Considerations
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This section of the work package provides information related to contingencies that may arise during the course of the maintenance activity. Scope expansion due to unforeseen or newly discovered deficiencies during the course of maintenance activities happens. It is unlikely (numerous possibilities) and infeasible (cost restrictive) to develop contingencies for all possible scenarios. The level of effort placed on contingency planning should be commensurate with the scope and significance of the maintenance activity. The planner should attempt to anticipate necessary contingencies based on previous work experience, operating history and other intelligence. Key considerations should be made in the areas of: 1. Potential scope expansion – Once a piece of equipment is opened for maintenance or inspection there is always the potential for work scope to increase. A review of previous maintenance history on the piece of equipment will provide valuable information to assist in development of contingencies. 2. Identify individuals to contact in case of certain events – The craftsman should be provided information in the work package on who should be notified if problems are encountered during the performance of the maintenance activity. This can be required for determination of whether parts should be replaced, scope expansion, engineering support for repair methods, etc. 3. Identify rapid or emergency actions to place equipment in compensatory configurations or conditions. 4. Develop material list for contingency and consumable parts – The planner should be aware that contingency parts may or may not be necessary to support the job. This can be a significant financial decision since most contingency parts tend to be high cost items that are not maintained in normal inventory. The parts should be flagged as contingent in the work package. It will be necessary to make a decision as to whether the parts should be on site to support the maintenance activity. Procurement should be notified of the contingent parts requirements so availability and lead times can be determined. This will allow a cost effective decision to be made with respect to whether the parts should procured or expedited to support the maintenance activity. Early identification of parts and contingent parts also allows sufficient time to determine parts obsolescence issues. Engineering can then be informed of the need for part evaluations to support the maintenance activity. Key Technical Point The level of effort placed on contingency planning should be commensurate with the scope and significance of the maintenance activity. The planner should attempt to anticipate necessary contingencies based on previous work experience, operating history and other intelligence.
Key O&M Cost Point The planner should be aware that contingency parts may or may not be necessary to support the job. This can be a significant financial decision since most contingency parts tend to be high cost items that are not maintained in normal inventory.
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3.4 Detailed Work Instructions
Figure 3.4 Work Package Development – Detailed Work Instructions This section of the work package provides the detailed sequence of steps required to perform the maintenance activity satisfactorily. This section also includes notes and cautions to provide the maintenance craftsman with amplifying information and alert them to critical attributes related to equipment or personal safety. The amount of detail that exists in this section can vary. This can be affected by the skill level of the craft, supervisory oversight provided and the work activity it self. The work package developer should not assume that the craftsman knows everything about the work activity. The developer can assume that each craftsman possesses the following skill set. 1. 2. 3. 4.
Can read engineering drawings Can read and understand work instructions Understands the proper application and use of hand tools. Can use measurement equipment.
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The draftsman will possesses many other skill sets but this will vary by craftsman based on the amount of training received, experience level and past work experience. The amount of detail required can also be affected by the amount of supervisory oversight provided. Oversight may be either form supervisors within the maintenance organization, engineering support or vendor support. Engineering and vendor support during a work activity will typically be known to the package developer and can be taken into account during package development. Supervisory support from within the maintenance organization is not as clear and should not be assumed to be present during the work activity with regard to the level of detail that should be included in the work package. The dominant factor n the level of detail required in the work instructions is the task itself. Tasks that are complex or less frequently performed will require a greater level of detail. Other factor that can affect the level of detail required include: 1. 2. 3. 4. 5.
The availability of approved, detailed procedures to perfo5rm the work activity. Risk to the unit (trip, transient) Personnel Safety The requirement for special controls (Confined work space) The requirement for special skills (Welding, rigging, etc)
NOTES are provided to give amplifying or clarifying information. NOTES should only contain administrative information. NOTES should not direct any physical actions required by the maintenance craftsman. NOTES should precede the step to which they apply. CAUTIONS are provided to heighten attention to step(s) that if improperly performed may result in equipment damage, injury to personnel, and impact to unit operation or adversely affect plant systems. CAUTIONS should precede the step to which they apply. To assist the craftsman in recognizing critical steps in the work instructions special symbols or annotations (Bomb or firecracker symbols, stop signs, etc) have been used to minimize the potential for errors. The work templates contained in this report provided varying levels of detail.
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3.5 Post Maintenance Testing
Figure 3.5 Work Package Development – Post Maintenance Testing This section of the work package provides post maintenance tests as well as activities that should be perform post maintenance to return the work location to pre-work conditions or better. Post maintenance testing is performed to verify that all components and systems are capable of performing their intended functions following maintenance activities. It will also verify that original deficiencies have been corrected and that no new deficiencies were introduced during the maintenance activity. The tests performed should be commensurate with the maintenance work performed and the importance of the equipment to facility safety and reliability. Post maintenance testing may be specified in the current work order package, a procedure or a subsequent work order package. Post maintenance testing may be performed with the equipment operating under normal operating conditions or specific test conditions. Post maintenance testing provides an initial break-in or run-in period for adjustments, calibrations and/or monitoring of equipment performance characteristics. (E.g. vibration, temperature, flow, etc)
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Post maintenance testing should include documentation of results for future reference and trending. 3.6 Feedback Mechanisms
Figure 3.6 Work Package Development – Feedback Mechanisms
Feedback provides information related to the quality of work in the field, processes that support work, and observation of work practices and conditions in the plant. Feedback is a vital link between the job-site and the organization. Feedback can be obtained through a variety of mechanisms. (E.g. direct observation of work performance, work package feedback sheets, post job reviews, Corrective Action Program, informal communications, etc) These methods of providing feedback on maintenance activities have been used with varying degrees of success. The maintenance organization should take advantage of as many of these mechanisms as possible. Each will provide a different perspective and insight into the maintenance work process. Feedback is a credible source of information that can result in the improvement in the organization of work, support worker performance, improve job productivity and identify opportunities to strengthen human performance and reduce errors. It can identify problems with procedures, work packages, equipment, work performance and training of personnel.
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Feedback should be obtained as soon as practical following the maintenance activity. It should focus on both improvement opportunities as well as recognizing those things that went well. Some typical items that should be considered for feedback include: 1. Unanticipated surprises 2. Unanticipated error precursors/traps 3. Industrial safety issues or hazards 4. Equipment condition 5. Personnel issues (lack of resources, incorrect resources, training inadequacies) 6. Work Order/Package quality 7. Procedure quality 8. Quality of supervision 9. Quality of vendor support (if applicable) 10. Quality of planning and scheduling 11. Adequacies of tools, parts, resources 12. Inter-departmental support 13. Obstacles to work performance 14. Things that went well 15. Good catches Key Human Performance Point Feedback is a credible source of information that can result in the improvement in the organization of work, support worker performance, improve job productivity and identify opportunities to strengthen human performance and reduce errors.
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3.7 References
Figure 3.7 Work Package Development - References
This section of the work package is the maintenance craftsman’s resource library. This section of the work package should provided sufficient supplemental information necessary to complete the maintenance activity satisfactorily. It is not possible to place all the resource information that may be used during the course of the maintenance activity into the work package. The package would become too bulky and could very likely turn off the craftsman to useful information contained within. However, the work package reference section should contain sufficient information that will be accessed during the maintenance activity and provide reference information in sufficient detail to allow the craftsman to easily retrieve the reference if required. In some cases, if they exist, whole or portions of procedures may be referenced. If portions of procedures are included as reference the planner should be careful to include the initial conditions, precautions and limitations applicable to that procedure to ensure that portion of the procedure is applied appropriately and under the proper circumstances. References may be included in whole, in part or noted for easy reference and access. Typical references may include:
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Included in package: 1. 2. 3. 4. 5. 6. 7. 8.
Approved procedures related to work activity (if they exist) Vendor drawings Complete parts list with appropriate stock numbers MSDS sheets for chemicals that will be used Electrical drawings (if applicable) Copy of the equipment clearance/tag out Operating Experience Any permits required (Confined space, hot work, etc)
Referenced or noted: 1. 2. 3. 4. 5. 6. 7. 8. 9.
Industrial Safety Manual Detained Post maintenance procedure (if it exists) Hot Work Permit Procedure Confined Work Space Procedure Chemical Control Procedure Foreign Material Control Procedure Technical support Procedures (Packing, torque, welding, etc) Equipment vendor technical manual Specific component vendor technical manual (Coupling, Mechanical seal, etc)
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4 REFERENCES 1. Electrostatic Precipitator Guidelines, Vol. 1: Design Specifications, Vol. 2: Operation and Maintenance, Vol. 3: Troubleshooting. EPRI, Palo Alto, CA: 1987. CS-5198, RP2243-1. 2. Heat Exchanger: An Overview of Maintenance and Operations, EPRI, Palo Alto, CA; 1997. TR-106741. 3. HVAC Fans and Dampers Maintenance Guide, EPRI, Palo Alto, CA; 1999, TR-112170. 4. Maintenance Work Package Planning Guidance, EPRI, Palo Alto, CA; 2005, 1011903. 5. Circuit Breaker Maintenance, Vol 1: Low Voltage Circuit Breakers, Part 1, ABB K-Line, EPRI, Palo Alto, CA; 1993. NP-7410. 6. Circuit Breaker Maintenance, Vol 1: Low Voltage Circuit Breakers, Part 2, GE-AK Models, EPRI, Palo Alto, CA; 1992. NP-7410. 7. Circuit Breaker Maintenance, Vol 1: Low Voltage Circuit Breakers, Part 3, Westinghouse DB Models, EPRI, Palo Alto, CA; 1992. NP-7410. 8. Circuit Breaker Maintenance, Vol 1: Low Voltage Circuit Breakers, Part 4, Westinghouse DS Models, EPRI, Palo Alto, CA; 1992. NP-7410. 9. Electrostatic Precipitator Maintenance Guide, Vol. 1, EPRI, Palo Alto, CA; 2003, 1007456. 10. Electrostatic Precipitator Maintenance Guide, Vol. 2, EPRI, Palo Alto, CA; 2003, 1007690. 11. Pulverizer Maintenance Guide, Vol 2, B&W Roll Wheel Pulverizers; EPRI, Palo Alto, CA; 2004. 1009508. 12. Belt Drive & Bearings Reference Guide, Emerson Power Transmission Manufacturing. 13. Power Zone 4 Low Voltage, Metal-Enclosed Drawout Switchgear, Class 6037, Instruction Bulletin, Square D, 1999-2003. 14. Limitorque SMB Series/SB Series Installation and Maintenance, Flowserve Corporation, 2004. FCD LMAIM1401-00. 15. Evolution Series E 9000 Motor Control Centers, Installation and Maintenance Guide, General Electric, 2001. DEH-40472 Rev 3. 16. Medium Voltage Motor Control Center, Installation and Maintenance Manual, ABB Power T&D, Nov 1998. Bulletin No. 1B3.2.7-7B. 17. Advantage Motor Control Centers, Installation and Maintenance Manual, Cutler Hammer, 2004. 1.B.8922-1A. 18. Guideline to Good Practices for Planning, Scheduling and Coordination of Maintenance or DOE Nuclear Facilities, US Department of Energy, 1993. DOE-STD-1050-93. 19. Guideline to Good Practices for Types of Maintenance Activities at DOE Nuclear Facilities, US Department of Energy, 1993. DOE-STD-1052-93.
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20. Military Handbook, Maintenance and Operation of Central Heating Plants, US Department of Defense, 1995. MIL-HDBK-1125/1. 21. Goulds Pumps, Goulds Vertical Turbine Pumps, Bulletin 3A.1, ITT Industries, 2004. 22. Thermostatic Steam Traps, Module 11.2, SC-GCM-80, Spirax-Sarco Limited, 2005. 23. Mechanical Steam Traps, Module 11.3, SC-GCM-81, Spirax-Sarco Limited, 2005. 24. Thermodynamic Steam Traps, Module 11.4, SC-GCM-82, Spirax-Sarco Limited, 2005. 25. Testing and Maintenance of Steam Traps, Module 11.14, SC-GCM-80, Spirax-Sarco Limited, 2005. 26. Steam Survey Guide, ORNL/TM-2001/263, Oak Ridge National Laboratory, Greg Harrell, 2002. 27. Inspect and Repair Steam Traps, Steam Tip Sheet #1, DOE/GO-102002-1503, Steam, US Department of Energy, 2002.
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A WORK PACKAGE TEMPLATE – BELT DRIVEN EQUIPMENT 1.0 Task Overview 1.1 Component type This work instruction is applicable to various belt driven types of equipment. It is applicable but not limited to air handling units (AHUs), fans, coolers, compressors, vacuum pumps, etc. 1.2 Equipment tag or unique equipment identifier Ensure unique equipment identifier is used to designate which piece of belt driven equipment is worked. 1.3 Scope This work instruction describes the disassembly, inspection, shaft/bearing alignment, sheave alignment, belt tension adjustment and reassembly of belt driven equipment. 1.4 Develop list of know consumable materials to be used A. B. C. D. E.
Container (bags) for temporary storage of studs and nuts Loctite Emery cloth Steel wool Grease (if applicable for bearing lubrication)
1.5 Develop a list of know parts to be replaced A. Belts B. Sheaves C. Shims 1.6 Special tools A. B. C. D. E. F. G.
Force gauge Belt tensioner Sheave Groove Gauge Torque wrenches Combination wrenches Socket set Allen wrenches
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H. Straight edge I. Dial indicators J. Level 2.0 Pre-job Brief 2.1 Evaluate potential for generation or equipment risk hazards A. Some fans have resonant frequencies. Belts should be adjusted appropriately to avoid fans potentially running at resonant frequencies. B. Some belts do not recommend the use of belt dressings. This could cause premature belt failure. (refer to belt manufacture with respect to belt dressings) C. It is recommended that belt tension be checked within 24 to 48 hours of installing new belts due to belt break-in stretch. D. If ventilation fans are being worked, resulting ventilation line-ups to support work can cause significant d/p’s across doors or other accesses posing a personnel safety hazard. 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation A. If work is performed inside plenums foreign material exclusion areas should be established. 2.3 Job Safety Analysis, Identifies general and specific hazards A. Some fans are located in common plenums and may require securing redundant fans to allow work to proceed safely. B. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work. 2.4 Identify permits required A. Equipment Clearance/Tag out Orders B. Confined Work Space (if applicable) C. Chemical Control Procedures (handing and disposal)
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2.5 Identify Environmental Consideration A. Refer to Material Safety Data Sheets (MSDS) for proper handling and disposal of special chemicals (E.g. cleaning solvents) B. Handling and disposal of chemicals (E.g. solvents, oil, grease, etc) should be in accordance with approved chemical control procedures 2.6 Identify Operating Experience Review any relevant plant specific or industry related operating experience applicable to the work being performed and the use of the tube cleaning equipment.
2.7 Identify Clearance/Tag out Boundary A. Motor to fan, compressor, cooler, AHU, etc B. Power to inlet and outlet dampers (if applicable) C. Power to common plenum/duct equipment (if applicable)
3.0 Contingency Considerations 3.1 Identify potential scope expansion and actions due to scope expansion A. Inspections of any components may result in the need to repair or replace components as appropriate. B. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work. 3.2 Identify individuals to contact in case certain events occur A. Contact planner if scope growth is identified during work instruction performance B. Contact supervision for any uncertainties with respect to the repair or replacement of worn or damaged parts identified during work instruction performance. C. Contact engineering if flow tests or vibration monitoring can not meet acceptable limits within the scope of work D. Contact vendor for any clarification of vendor information or additional vendor assistance is required 3.3 Identify rapid or emergency actions to place equipment in likely
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compensatory configurations or conditions 3.4 Develop material list for potential contingency and consumable parts A. Bearings B. Shaft
4.0 Detailed Work Instructions Develop work instructions, utilize existing procedures when applicable Provide expected actions in proper sequence for task. Identify Notes and Cautions where needed A. B. C. D. E.
NOTIFY Operations prior to beginning work ENSURE an appropriate clearance/tag out is in place to perform work safely ENSURE all parts expected to be used are available and in hand ENSURE all tools necessary to perform the job are available ENSURE appropriate personal safety equipment is worn on the job
4.1 Disassembly NOTE Bag or tag parts for traceability. A. REMOVE as applicable: a. Guards b. Covers c. Access Ports d. Bolts, screws and/or fasteners CAUTION Do not pry belts off of sheaves as this may damage belts and sheaves.
NOTE Belts should not ride in the bottom of a sheave groove.
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B. REDUCE sheave center-to-center distance between the motor sheave and the driven sheave to allow removal of belts. C. LIFT belt(s) off sheave
4.2 Inspections NOTES 1. 2. 3. 4. 5.
Worn or damaged parts should be repaired or replaced if required Old and new belts should be inspected prior to use Wear on one side of a belt is an indication of improper sheave alignment. Belts that are hard and brittle are typically a result of lack of tension. Spin burns or glazed shinny side walls is an indication of belt slippage.
A. INSPECT belts for: A. Cover fabric ruptures B. Cracks C. Slip burn areas D. Separation of plies E. Ruptures F. Worn belt sides NOTES. 1. Sheaves with burrs, rough spots or corrosion may be cleaned. 2. Sheaves with cracks or dished sides should be replaced. 3. If sheave is dished greater than 1/32”, the sheave should be replaced.
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G. INSPECT sheaves for: a. Burrs b. Rough spots c. Corrosion d. Pitting e. Cracks f. Dished sides NOTE Major shaft defects can sometimes be discovered by rotating shaft by hand and listening/feeling for unusual noises and/or rough spots.
H. INSPECT shaft for rough spots, burrs, or other damage or degradation. I. INSPECT bearings for any defects or misalignment J. INSPECT bearing set screws are tight NOTE Some pillow block bearings require lubrication. Refer to vendor for approved lubricants.
CAUTION Do not apply excessive pressure when lubricating to prevent damage to bearing seals.
K. LUBRICATE bearings (if required) L. INSPECT the following for unusual wear: a. Shaft coupling b. Housings c. Mounting bases d. Fan wheel
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4.3 Alignments
4.3.1 Sheave alignment
CAUTION Do not roll or pry belts off of sheaves as this may damage belts and sheaves. NOTE Sheaves should be placed as close to the bearings as possible to create less shaft deflection and bearing stresses. A. ALIGN motor sheave to driven sheave a. Laser alignment b. Straight edge alignment c. String alignment 4.3.2 Shaft/Bearing Alignment (required only if shaft or bearing is replaced)
A. B. C. D. E. F. G. H.
INSPECT bearing and ensure it is centered in its housing VERIFY Shaft is level, in the same plane (prime mover and driven unit) ADJUST bearings as needed to achieve shaft s in the same plane. For fans: ENSURE fans are centered radially and axially. TIGHTEN bearing hold down bolds (snug tight) POSITION dial indicators on shaft at pillow block bearing. LOOSEN pillow block hold down bolts OBSERVE dial indicators for movement to determine if shaft was preloaded. a. For vertical movement add or delete shims as necessary on pillow block bearing or adjust flange bearings b. For horizontal movement, adjust bearings as necessary I. REPEAT dial indicator test for shaft preload until acceptable results are achieved J. TORQUE bearing hold down bolts when satisfactory shaft alignment is achieved. K. RECHECK alignment
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4.3.3 Adjusting belt tension
1. 2. 3. 4. 5. 6. 7. 8. 9.
NOTES Ideal belt tension is the lowest tension that will prevent prolonged belt squeal on startup and excessive vibration during operation. Refer to vendor manuals for appropriate belt tensions The shaft deflection method is a recommended method for belt driven HVAC equipment. After installation of new belts, belts should be tensioned to maximum allowable force to allow for break-in stretch Over tensioning belts shortens belt and bearing life. Under tensioning belts can cause premature belt ware or fan failure. Some fans have resonant frequencies that must be avoided. For multiple belt sets do not mix old and new belts. The most common reason for belt failure is under tension.
4.3.3.1 Shaft deflection method
A. B. C. D.
INSTALL dial indicator at closest accessible location to the centerline of sheave. APPLY tension to belt until shaft movement is detected not to exceed 0.001 inch MEASURE belt span to +/- 1 inch DIVIDE span by 64 to obtain deflection NOTES 1. For a banded belt, Average force equals total force divided by the number of belt ribs. 2. Deflection force should be measured as close to the center between the two sheave axis.
E. MEASURE force in pounds required to deflect each of the belts a distance equal to the deflection distance F. CALCULATE average force
4.3.4 Reassembly
A. INSTALL all bolts, screws and fasteners (torque as specified) NOTE If work was performed inside a plenum ensure are materials taken into plenum have been removed.’
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B. INSTALL guards, covers and access ports
5.0 Determine PMT and PMT considerations
A. Vibration testing is recommended for all corrective maintenance B. Flow testing is recommended for sheave replacements if flow is critical to proper operations of equipment or supported equipment cooling. C. Additional belt tension adjustments may be required to achieve acceptable vibration levels or to eliminate belt squeal
6.0 Feedback Mechanisms Identify mechanism to provide work order feedback for improvements and errors A. Perform post job review B. Initiate any corrective action program documents necessary to resolve any problem areas identified.
7.0 References A. B. C. D. E.
Industrial Safety Manual Applicable vendor technical manuals (Belts, sheaves, bearings, driven equipment) Foreign Material Control Procedure Material Safety Data Sheets Chemical Traffic Control Procedure
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B WORK PACKAGE TEMPLATE - BOILER FEED WATER PUMP 1.0 Task Overview 1.1 Component type This work instruction is applicable to a single stage, pack-less boiler feed water pump.
1.2 Equipment tag or unique equipment identifier
Ensure the unique boiler feed water pump identifier is used to designate which boiler feed water pump is being worked.
1.3 Scope This work instruction provides instructions for the disassembly and assembly of a single stage, pack-less boiler feed water pump. It also provides steps for the removal and installation of subsystems. Various inspections, cleaning and lubrication information is also provided.
1.4 Develop list of know consumable materials to be used A. B. C. D. E. F.
Grease (for gear type coupling installation) Containers (bags) for temporary storage of parts Clean rags Oil drain pan Bearing oil (as per vendor manual) Silicon grease
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G. H. I. J. K.
Anti seize Permatex Cleaning solvent (Isopropyl alcohol, acetone, act.) Rubber gloves Duct tape
1.5 Develop a list of know parts to be replaced A. Various gaskets (case to cover, bearing brackets, etc) B. Various O-rings (Stuffing box bushing, cover, etc) C. Various seals
1.6 Special tools A. B. C. D. E. F. G. H. I. J. K. L. M. N.
Chain falls, rigging, hoists, slings etc Combination wrenches Allen wrenches Various sockets Plasti-gage for bearing clearances Bearing heater for coupling hub Tempilstick (as per vendor manual for coupling hub) Cribbing (to support rotating element, if removed) Coupling puller Dial indicators Feeler gauges Inside and outside micrometers Torque wrenches (various) Alignment equipment
2.0 Pre-job Brief 2.1 Evaluate potential for generation or equipment risk hazards This work is typically performed during an outage period. However, if it can be performed with the unit on line other considerations are reduced load operation, and working around thermally hot components.
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2.2 Identify Foreign Material Exclusion (FME) potential and mitigation A. Performance of this work will open various piping systems and a major piece of plant equipment. Appropriate measures (covering pipe ends, covering casing) should be taken to prevent foreign material from entering the system. 2.3 Job Safety Analysis, Identifies general and specific hazards A. If pump uses EPT O-Rings, they are susceptible to deterioration and failure if they come in contact with petroleum based products. B. Depending on material some pump shafts are susceptible to stress corrosion cracking. Refer to vendor manual for proper chemicals that may be used on shaft. 2.4 Identify permits required A. B. C. D.
Equipment Clearance Orders Open Flame Permits/Hot Work Permits Chemical Control Transient Fire Load Permit (cleaning solvents, oil, grease, rags, etc)
2.5 Identify Environmental Consideration A. Refer to Material Safety Data Sheets (MSDS) for proper handling and disposal of special chemicals (E.g. cleaning solvents) B. Handling and disposal of chemicals (E.g. solvents, oil, grease, etc) should be in accordance with approved chemical control procedures 2.6 Identify Operating Experience Review any relevant plant specific or industry related operating experience applicable to the work being performed.
2.7 Identify Clearance/Tag out Boundary NOTE MFW pump prime mover may be either an electric motor or a steam driven turbine. Prime mover shall be cleared as part of clearance/tag out boundary
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A. B. C. D. E. F. G. H. I.
Motor breaker or steam supply valve Motor heater breaker (if applicable) Pump supply valve Pump discharge valve Pump vent valve Pump drain valve Lube oil supply breaker (if applicable) Lube oil supply and discharge valves (if applicable) Cooling water supply and discharge valves
3.0 Contingency Considerations 3.1 Identify potential scope expansion and actions due to scope expansion A. Inspections of any components may result in the need to repair or replace components as appropriate. B. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work. 3.2 Identify individuals to contact in case certain events occur A. Contact planner if scope growth is identified during work instruction performance B. Contact supervision for any uncertainties with respect to the repair or replacement of worn or damaged parts identified during work instruction performance. C. Contact engineering if flow tests or vibration monitoring can not meet acceptable limits within the scope of work D. Contact vendor for any clarification of vendor information or additional vendor assistance is required
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3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions 3.4 Develop material list for potential contingency and consumable parts A. B. C. D.
Rotating element Coupling (as per vendor manual) Wear ring Bearings
4.0 Detailed Work Instructions Develop work instructions, utilize existing procedures when applicable Provide expected actions in proper sequence for task. Identify Notes and Cautions where needed A. B. C. D. E. F.
NOTIFY Operations prior to beginning work ENSURE an appropriate clearance/tag out is in place to perform work safely ENSURE all parts expected to be used are available and in hand ENSURE all tools necessary to perform the job are available ENSURE appropriate personal safety equipment is worn on the job ENSURE all rigging, hoists, chain falls, slings etc. are available and have been inspected prior to use
4.1 Preparations A. VERIFY clearance/tag out is correctly in place B. LOCATE and ENSURE proper piece of equipment is being worked per the work instruction C. ENSURE appropriate laydown areas are prepared for temporary storage of removed components CAUTION Instrumentation and associated cabling can be easily damaged. Care must be exercised during disassembly to prevent damage to either instruments or cables.
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D. REMOVE instrumentation (temperature, vibration, etc) CAUTION Ensure insulation does not contain asbestos. If asbestos is present, asbestos abatement must be used to remove insulation.
E. REMOVE insulation and store appropriately F. REMOVE any piping, equipment supports and other interferences as required 4.2 Removal of Subsystems NOTE Removed piping ends should be covered after removal to prevent entry of foreign material.
A. REMOVE seal water piping (if pump covers are to be removed) B. REMOVE instrumentation (if not previously removed) NOTE Oil systems may contain orifices. Care should be taken to ensure these are recognized, marked and saved for reinstallation.
C. REMOVE oil piping (if bearing housings are to be removed) 4.3 Disassembly NOTE Engineering may require as found alignment data prior to disassembly.
A. MEASURE as-found coupling alignment (if required) Horizontal offset Vertical offset Angular face alignment
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NOTE Matchmark spool piece to hubs. Match mark coupling hubs and diaphragm packs.
B. REMOVE coupling guard C. REMOVE spool piece (if present) NOTES 1. Match mark couplings prior to removal. 2. If coupling hub is to be removed from pump shaft heat will be required. Hot work permit required. 3. Various types of coupling arrangements are used in the industry. Follow applicable vendor disassembly instructions for removal. D. REMOVE coupling E. DISASSEMBLE thrust end (depending on pump design some components may or may not be present) (Refer to vendor manual) a. Thrust deflectors b. Thrust bearing housing c. Journal bearing d. Oil seal e. Thrust bearing assembly f. Bearing housing bracket g. Stuffing box (bushings, o-rings, etc) F. DISASSEMBLE thrust end (depending on pump design some components may or may not be present) (Refer to vendor manual) a. Thrust deflectors b. Thrust bearing housing c. Journal bearing d. Oil seal e. Thrust bearing assembly f. Bearing housing bracket g. Stuffing box (bushings, o-rings, etc) G. REMOVE pump cover and gasket NOTE If rotating element is to be removed, protective sleeves should be placed on shaft to protect bearing surfaces.
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H. REMOVE rotating element NOTE If impeller is to be removed, this is typically an interference fit over a drive key. Heat will be required for removal. Obtain a hot work permit.
CAUTION Do not exceed vendor recommendations on max temperature allowed. Rotate heat for even distribution keeping flame away from shaft.
CAUTION If during the removal process the impeller binds on the shaft, allow shaft and impeller to cool and then repeat heating removal steps. Attempting to continue with removal can damage shaft. I. REMOVE impeller J. REMOVE wear ring
4.3.1 Cleaning, Inspection, Lubrication
NOTE During cleaning steps follow guidance of MSDS sheets, chemical control procedures and temporary storage of combustible materials. A. CLEAN parts with appropriate cleaning solution and dry with lint free rags NOTES 1. Any worn or defective parts should be replaced. 2. If bearings are found wiped or degraded the oil sump strainer and oil drain piping should be inspected and cleaned as required. B. INSPECT parts for wear, erosion and corrosion a. Rotating element b. Casing internals c. Bearing bracket covers d. Bearings (inboard, outboard, thrust bearings) e. Bearing housings
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f. Oil deflectors C. INSPECT pump shaft a. NDT (optional based on need, UT length, PT journal bearing area, PT under coupling area. b. Shaft runout c. Radial end wear ring and thrust end wear ring d. Inboard and outboard stuffing box bushings NOTE All flanges and gasket surfaces should be free of dirt, grit, grease, oil or other visible contaminants.
D. CLEAN gasket mating surfaces (honing may be required) E. CLEAN bolts and threaded holes F. LUBRICATE threads of studs/bolts with never seize.
4.3.2 Reassembly
A. REPLACE wear ring ***** If impeller was removed ***** NOTES 1. Proper heating of impeller requires slow even heat distribution. 2. Temperature of impeller should be monitored during heating. Do not exceed vendor temperature limits.
B. INSTALL impeller ***** If shaft was removed ***** NOTES 1. Shaft should be rotated at various stages of reassembly to detect any binding. 2. Pre-lube bearings before rolling shaft.
C. INSTALL pump gasket and cover
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D. INSTALL rotating element (shaft and impeller) NOTES 1. During reassembly appropriate torque techniques should be followed. 2. Lubricate o-rings with approved lubricant prior to installation. 3. Measure bearing clearances after installation of bearings. Clearance should be within vendor requirements. E. REASSEMBLE thrust end (depending on pump design some components may or may not be present) (Refer to vendor manual) a. Thrust deflectors b. Thrust bearing housing c. Journal bearing d. Oil seal e. Thrust bearing assembly f. Bearing housing bracket g. Stuffing box (bushings, o-rings, etc) F. REASSEMBLE thrust end (depending on pump design some components may or may not be present) (Refer to vendor manual) a. Thrust deflectors b. Thrust bearing housing c. Journal bearing d. Oil seal e. Thrust bearing assembly f. Bearing housing bracket g. Stuffing box (bushings, o-rings, etc) G. ENSURE shaft rotates freely H. CENTER rotating element axially I. CHECK Thrust Disc Face alignment J. ASSEMBLE outboard and inboard bearings K. SET thrust bearing end play L. ASSEMBLE a. Oil deflectors b. Stuffing box covers c. Fill lube oil tank (vendor recommended oil) d. Ensure shaft rotates freely NOTE Observe match marks
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A. B. C. D.
INSTALL coupling INSTALL spool piece PERFORM cold alignment INSTALL coupling guard
NOTE If boiler feed pump lube oil sense line was disconnected, backfill line to purge air E. INSTALL subsystems Oil piping Seal water piping Instrumentation
5.0 Determine PMT and PMT considerations A. RELEASE clearance/tag out B. CHECK for leaks (oil, water) C. When pump is capable of being run a. PERFORM vibration testing b. MEASURE inboard and outboard bearing temperatures (vendor recommendation) D. Hot alignment (if required)
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E. Work site cleanup REINSTALL any interferences removed to support access to work REINSTALL insulation CLEAN work area to original pre-maintenance conditions F. RETURN unused parts to storeroom
6.0 Feedback Mechanisms Identify mechanism to provide work order feedback for improvements and errors A. Perform post job review B. Initiate any corrective action program documents necessary to resolve any problem areas identified.
7.0 References A. B. C. D. E. F. G.
Industrial Safety Manual Applicable vendor technical manuals (boiler feed pump, coupling, bearings) Foreign Material Control Procedure Material Safety Data Sheets Chemical Traffic Control Procedure Hot work procedure Storage of temporary combustibles
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C WORK PACKAGE TEMPLATE – HEAT EXCHANGER 1.0 Task Overview 1.1 Component type This work instruction is applicable to a single pass horizontal heat exchanger. However, many aspects are applicable to U-tube type heat exchangers.
1.2 Equipment tag or unique equipment identifier Ensure the unique heat exchanger identifier is used to designate which heat exchanger is to be worked on.
1.3 Scope This work instruction provides instructions for the disassembly of a heat exchanger, cleaning, pressure testing, repairs of tube and tube to tube sheet leaks and reassembly.
1.4 Develop list of know consumable materials to be used A. B. C. D. E. F. G. H. I.
Container (bags) for temporary storage of studs and nuts Tube plugs (type as specified by vendor) Isopropyl Alcohol, Acetone or DI water Clean rags Thread Lubricant Flat scraper Emery cloth Marker to identify problem tubes Buckets
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1.5 Develop a list of know parts to be replaced A. B. C. D. E.
Gasket material Studs Nuts Washers Zincs (if applicable)
1.6 Special tools A. B. C. D. E. F. G. H. I. J. K. L. M. N.
Rotary grinder, with bits and disks Stainless steel brush Eyebolts, slings chokers, come-a longs Endplate removal fixture (if specified for the heat exchanger) Tube cleaning equipment (pump, hoses, cleaners) Borescope (Tube fouling inspection if required) Leak testing equipment Rolling tool Torque wrenches Wooden blocks to support end plate of hinge type design Pop-a-Plug hydraulic equipment (if this method of tube plugging is used) Lighting (Low voltage or GFIC protected) Ventilation fans (if needed) Personal protective equipment (hard hat, eye glasses, safety shields, gloves, breathing dust masks, etc)
2.0 Pre-job Brief 2.1 Evaluate potential for generation or equipment risk hazards
If this work is being performed with the unit on line it is possible that the heat exchanger being worked may be supporting cooling to various pieces of running equipment. Load reduction may be required to perform heat exchanger maintenance. Ensure running equipment has adequate flow to ensure proper cooling of the equipment. Running equipment should be monitor frequently, especially following removal of the heat exchanger. Running equipment temperatures should be stabilized prior to disassembly of the heat exchanger in the event the heat exchanger must be returned to service.
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A. House keeping should be maintained clean to minimize potential for safety hazards B. All parts (nuts, bolts, washers, studs, etc) should be suitably identified and stored to ensure proper orientation and reinstallation. 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation A. House keeping at the job site should be maintained to minimize the potential for foreign material from entering the heat exchanger. The heat exchanger end bell should be inspected for cleanliness prior to closure. 2.3 Job Safety Analysis, Identifies general and specific hazards A. Unnecessary personal safety hazards may result if proper housekeeping is not maintained. B. Tube cleaning equipment operates under extremely high pressure and can cause serious personal injury. Personnel operating tube cleaning equipment should be trained and familiar with operating of equipment. C. Ensure the end of the heat exchanger where cleaners are shot out is appropriately covered to prevent personal injury due to a missile. D. Work area should be roped off or marked appropriately for hazards present on the job. E. Tube cleaning equipment shall have a “deadman’s” switch controlled by the operator. F. Cleaning solvents can be volatile. Ensure MSDS (Material Safety Data Sheets) have been reviewed and appropriate guidance followed for the handling, temporary storage and disposal on any applicable materials used. G. Some heat exchanger fluid systems contain various corrosion inhibitor chemicals. MSDS sheets should be reviewed for any applicable precautions and requirements. H. Ensure any load lifting equipment is in good repair and of proper load bearing size for loads to be lifted. I. Nuts, bolts, studs, washers and any disassembled parts should be identified and stored properly to ensure control and availability for reinstallation. 2.4 Identify permits required A. Define appropriate Clearance/Tag Out boundary and ensure all planned work activities are with in the identified clearance/tag out boundary. B. Identify if any chemical use permits are required for special chemicals or solvents. (Chemical Control Procedure, Material Safety Data Sheets) C. Transient fire loads should have appropriate permits.
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2.5 Identify Environmental Considerations A. Review appropriate MSDS sheets and in-house chemical use procedures for any special chemicals or solvents used. B. Identify reporting limits and requirements for any accidental release of chemicals or solvents to the environment C. Identify and special handling or temporary short-term storage requirements for any specials chemicals or solvents required. D. Some heat exchangers contain corrosion inhibitor chemicals. When draining heat exchangers ensure MSDS sheets are reviewed for any applicable precautions and requirements. 2.6 Identify Operating Experience Review any relevant plant specific or industry related operating experience applicable to the work being performed and the use of the tube cleaning equipment.
2.7 Identify Clearance/Tagout Boundary A. B. C. D. E.
Inlet and outlet valves and bypass valves for the tube process fluid Inlet and outlet valves and bypass valves for the shell process fluid Tube side drain and vent valves Shell side drain and vent valves Power to electronic corrosion control equipment (if applicable)
3.0 Contingency Considerations 3.1 Identify potential scope expansion and actions due to scope expansion A. B. C. D.
Tube plugging activities Tube to tube sheet leak repairs Coating repairs Corrosion/Erosion repairs
3.2 Identify individuals to contact in case certain events occur A. Contact planner if scope growth is identified during work instruction performance
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B. Contact supervision for any uncertainties with respect to the repair or replacement of worn or damaged parts identified during work instruction performance. C. Contact vendor for any clarification of vendor information or additional vendor assistance is required D. Engineering should be notified of any erosion/corrosion problems identified 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions 3.4 Develop material list for potential contingency and consumable parts A. Tube plugs (type as per vendor) B. Coating materials
4.0 Detailed Work Instructions Develop work instructions, utilize existing procedures when applicable Provide expected actions in proper sequence for task. Identify Notes and Cautions where needed A. B. C. D. E.
NOTIFY Operations prior to beginning work ENSURE an appropriate clearance/tag out is in place to perform work safely ENSURE all parts expected to be used are available and in hand ENSURE all tools necessary to perform the job are available ENSURE appropriate personal safety equipment is worn on the job
4.1 Disassembly: A. ENSURE FME requirements are in place, work area is clean and appropriate work boundaries have been established B. REMOVE insulation if heat exchanger has insulation on heat exchanger channel heads end plates to allow access to studs. C. STORE insulation for personal safety and preservation of insulation.
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CAUTION Heat exchanger end plates are extremely heavy. Ensure lifting equipment is appropriate for load being lifted. If end plate is moved to a location for temporary storage, ensure it is adequately secured to prevent accidental rolling or tipping.
NOTES 1. Some end plates require special lifting rigs. Refer to vendor manual. 2. Some end plates are on hinges. When end plate is swung open ensure blocks are positioned under end plate to minimize forces on the hinges. 3. Results of inspection could require scope change to the work instructions to correct identified discrepancies
D. REMOVE end plate studs and remove end plates at each end of heat exchanger. E. SECURE end plates to an adequate fixture. F. REMOVE and discard end plate gaskets CAUTION Lighting should be either low voltage or protected by Ground Fault Circuit Interrupter (GFCI) NOTES 1. Establish any Confined Space Work requirements if applicable. 2. If metal tube plugs are used in the heat exchanger the tube sheet should be inspected in the area of these plugs for tube plug initiated stresses. G. INSTALL adequate lighting in heat exchanger H. PERFORM inspection of heat exchanger a. Corrosion b. Erosion c. Fouling d. Coatings e. Zincs f. Debris or foreign material g. General cleanliness h. Evidence of vibration (chafing, score marks, bright metal, weld cracks, etc) i. Leak indications beneath Heat exchanger or else where j. Tube plug degradation (improper installation, looseness, missing) k. Tube end splitting
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l. Failed or cracked welds m. Vibration damage 4.2 Cleaning: NOTES 1. Some cleaners have limited lifetime (10-15 shootings) Ensure adequate number of cleaners is available. 2. Appropriate ventilation and/or personal safety equipment may be A. B. C. D.
REMOVE all loose corrosion from tube sheet and inside surface of heat exchanger CLEAN tubes using tube cleaning system or hyrolazing equipment. ENSURE all cleaners are removed from heat exchanger following cleaning if used CLEAN heat exchanger channel heads
4.3 Heat Exchanger Testing: NOTES 1. Heat exchanger testing for tube integrity can be performed by either Eddy Current Testing (ECT) or performance of a leak test. 2. Leak tests can be performed using system pressure or with leak test equipment using either water. Air, helium etc. A. PERFORM ECT (Typically a function of specialized ECT personnel) ***** “OR” *****
4.3.1 Leak Testing
4.3.1.1 Leak Testing using System Pressure
A. B. C. D. E.
OBTAIN temporary lift of clearance/tag out boundary on shell side of heat exchanger. PRESSURIZE slowly (fill and vent) shell side of heat exchanger to system pressure. MAINTAIN heat exchanger shell side at system pressure for approximately 30 minutes INSPECT tube sheet for leaks RECORD any leaks identified and characterize as to whether the leak is a tube or tube to sheet leak
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F. RELIEVE system pressure slowly G. RE-ESTABLISH clearance boundaries
4.3.1.2 Leak Testing using Hydro Pump
CAUTION Leak test pressure shall not exceed the design pressure of either the shell or tube side of the heat exchanger
A. OBTAIN necessary temporary lifts on clearance/tag out to install pressure testing equipment B. INSTALL a relief valve with a set pressure less than or equal to design pressure of shell or tube design pressure, whichever is lower C. ENSURE area is roped off for personal protection CAUTION Head pressure effects must be accounted for if the pressure gauge elevation is significantly different from heat exchanger elevation.
D. E. F. G. H. I.
ATTACH pressure gage to leak testing equipment INSTALL pressure testing equipment PRESSURIZE HX to test pressure MAINTAIN heat exchanger shell side at system pressure for approximately 30 minutes INSPECT tube sheet for leaks RECORD any leaks identified and characterize as to whether the leak is a tube or tube to sheet leak J. RELIEVE system pressure slowly K. REMOVE pressure testing equipment L. INSTALL original equipment clearance/tag out boundary 4.4 Leak Repairs 4.4.1 Tube to Tube-Sheet Leaks
A. MEASURE inside diameter (ID) of problem tubes B. COMPARE ID of problem tubes to acceptance criteria C. IF ID is less than acceptance criteria THEN:
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a. CLEAN inside diameter of problem tubes (depth determined by vendor manual) CAUTION Do not damage tube sheet or coatings during cleaning process b. ROLL each tube to acceptance criteria c. MEASURE ID of rolled to verify acceptance criteria D. PERFORM leak test again after all problems tubes are rolled and meet acceptance criteria. E. IF ID was greater than acceptance criteria THEN REFER to engineering for appropriate corrective actions to take for repair.
4.4.2 Tube leaks
NOTES 1. Tube maps should be generated to show which tubes have been plugged. 2. Ensure adequate plugging margin for the heat exchanger will not be exceeded after plugging operations. 3. There are various types of tube plugs; driven plugs, welded plugs, Pop-a Plugs. Refer to vendor manual for type of plug to use. 4. If tube stabilization is required (e.g. rod or wire stabilization) refer to vendor manual.
A. IDENTIFY problem tubes to be plugged CAUTION Do not damage tube sheet or coatings during cleaning process.
B. CLEAN both ends of tubes to be plugged CAUTION If driven plugs are used, heavy hammering may result in damage to tube sheet.
C. INSTALL tube plugs into each end of the problem tubes
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NOTE Leak tests should be re-performed following any tube or tube to tube sheet leak repair.
4.5 Reassemble Heat Exchanger A. REMOVE all tolls, equipment, etc from heat exchanger channel head B. CLEAN the inside surfaces of the heat exchanger channel heads C. VERIFY heat exchanger channel heads are free of foreign material and other objects CAUTION Do not damage gasket sealing surfaces during cleaning process. D. CLEAN the gasket sealing surface on both channel heads and both end plates using a flat scraper and fine emery cloth NOTE A leak path is a defect across the gasket sealing surface E. F. G. H. I. J. K.
VERIFY sealing surfaces are free of foreign material and no leak paths exist. CLEAN threads on studs and bolts to remove foreign material, rust, corrosion and burrs VERIFY threads and studs are clean and damage free INSTALL a new gasket POSITION end plate to heat exchanger channel head flange INSTALL all studs and nuts and snug tight TORQUE flange nuts as required (refer to vendor tech manual)
5.0 Determine PMT and PMT considerations A. B. C. D. E. F.
RELEASE clearance/tag out for return to service (Operations) VERIFY no leaks observed at sealing services INSTALL insulation (if applicable) CLEAN work area DISPOSE of any special chemicals or solvents used appropriately RETURN unused parts to stores
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6.0 Feedback Mechanisms Identify mechanism to provide work order feedback for improvements and errors. A. Perform post job review B. Initiate any corrective action program documents necessary to resolve any problem areas identified. C. Ensure tube plugging maps are updated
7.0 References Identify typical references needed to perform the identified work A. B. C. D. E. F. G. H. I.
Heat Exchanger Vendor Tech manual Tube cleaning or Hydrolazing Equipment Tech Manual Tube Plugging Instruction Tube Sheet Map Tube Rolling Instruction Material Safety Data Sheets Chemical Control Procedures Foreign Material Control Corrosion Control
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D WORK PACKAGE TEMPLATE – LOW VOLTAGE BREAKER OVERHAUL NOTE This work instruction is written based on a generic low voltage breaker overhaul. Breaker design varies by manufacturer. This work template is based on information associated with Westinghouse, General Electric and ABB low voltage circuit breakers. Various components listed in each subsection may or may not be installed on a given breaker. Refer to specific breaker technical manual for components installed.
CAUTION Refer to specific vendor manual for breaker being overhauled. CAUTION This maintenance should only be performed by properly trained maintenance personnel who have received specialized training and demonstrated proficiency in the overhaul of the specific type of breaker being overhauled.
1.0 Task Overview 1.1 Component type This work instruction is applicable to Low Voltage breakers (typically 225 – 600 VAC).
1.2 Equipment tag or unique equipment identifier Ensure the unique breaker identifier is used to designate which breaker is to be worked on.
1.3 Scope This work instruction provides instructions overhaul of Low Voltage breakers (225 – 600 VAC).
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1.4 Develop list of know consumable materials to be used A. B. C. D. E. F. G. H. I. J. K. L.
Light oil Lubricant (Vendor approved) Cleaning brushes (no metal) Clean lint free rags Soft bristle brush (Non metal) Approved solvent or isopropyl alcohol Degreasing solvent (vendor approved e.g. Varsol) Silver plate cleaner for contacts (vendor approved e.g. Tarnex) Glass cleaner (ammonia based) Anti-oxidizing lubricant Scotch-brite Fine sandpaper Molybdenum Disulfide
NOTE The part list is based on parts that would be replaced during a typical breaker overhaul regardless of breaker manufacturer.
1.5 Develop a list of know parts to be replaced A. B. C. D. E. F. G. H.
Stationary and Moving main contacts Arc chutes Auxiliary switch Shunt trip device and shunt coils UV device and coil Various fasteners, clips, etc (Typically supplied as kits) Spring assemblies Operating mechanism components (Oscillator assembly, motor cutoff switch lever, trip shaft return spring)
1.6 Special tools A. B. C. D. E.
Proper breaker lifting device/hoist Flat, low dolly for breaker transport Power supply (appropriate voltage to check breaker control components) Multimeter (to measure control circuit voltages and low resistance) Vacuum cleaner
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F. G. H. I. J. K. L. M. N.
500 to 1000 volt megger Breaker Rack Out Tool/Wrench Overcurrent trip device test set (with timer) Amptector Trip Unit Test Set Spring force scale (~ 50 oz) Electrician’s tools (sockets, combination wrenches, screwdrivers, pliers, etc) Feeler gauges Dial Caliper Extra fine files
2.0 Pre-job Brief 2.1 Evaluate potential for generation or equipment risk hazards A. Operations must be notified of impending breaker to be removed for maintenance. 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation A. Housekeeping at the job site should be maintained to minimize the potential for foreign material from entering the MCC/LCC or associated buss work. B. Work area should be roped off to preclude personnel from entering a potential shock hazard area and temporary storage of removed breaker baskets/buckets. 2.3 Job Safety Analysis, Identifies general and specific hazards A. There are potential hazards of electrical shocks and/or burns whenever working in or around electrical equipment. Awareness to electrical hazards should be observed in the field, or at the workbench/test area. B. Appropriate Personal Protective equipment should be worn to preclude shock or arc flash injuries. (As per Facility Electrical safety Manual, NFPA 70E, OSHA, etc) C. Personnel working on breakers should have received the proper training and be qualified and proficient for work on the specific type of breaker being overhauled D. When working inside a breaker, always keep hands clear of moving breaker parts. E. Never place hands inside a breaker until the breaker closing springs have been verified to be DISCHARGED. F. Ensure hands, tools, test leads and other objects are clear of any moving breaker parts to prevent injury to personnel or damage to the breaker. G. Do not insert a breaker into the cubicle unless the arc chutes are installed.
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H. A breaker lifting device/hoist should be used to remove and install a breaker from its cubicle. I. A low dolly should be used to move the breaker to its work location to prevent the possibility of tipping. J. Older breakers may have arc chutes that contain asbestos. The presence or absence of asbestos should be verified prior to performing any work on arc chutes. 2.4 Identify permits required A. Define appropriate Clearance/Tag Out boundary and ensure all planned work activities are with in the identified clearance/tag out boundary. B. Identify if any chemical use permits are required for special chemicals or solvents. (Chemical Control Procedure, Material Safety Data Sheets) 2.5 Identify Environmental Consideration A. Review appropriate MSDS sheets and in-house chemical use procedures for any special chemicals or solvents used. B. Identify reporting limits and requirements for any accidental release of chemicals or solvents to the environment C. Identify and special handling or temporary short-term storage requirements for any specials chemicals or solvents required. 2.6 Identify Operating Experience Review any relevant plant specific or industry related operating experience applicable to the work being performed and the use of the tube cleaning equipment.
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2.7 Identify Clearance/Tagout Boundary A. Specific breaker to be clean and inspected B. Control power fuses (if required)
3.0 Contingency Considerations 3.1 Identify potential scope expansion and actions due to scope expansion A. Defective parts identified in breaker inspection 3.2 Identify individuals to contact in case certain events occur A. Contact planner if scope growth is identified during work instruction performance B. Contact supervision for any uncertainties with respect to the repair or replacement of worn or damaged parts identified during work instruction performance. C. Contact supervision if any problem is identified that prevents following work instructions D. Contact vendor for any clarification of vendor information or additional vendor assistance is required 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions 3.4 Develop material list for potential contingency and consumable parts A. Complete spare breaker (Tested) B. Complete spare Operating Mechanism
4.0 Detailed Work Instructions Develop work instructions, utilize existing procedures when applicable Provide expected actions in proper sequence for task. Identify Notes and Cautions where needed Prerequisites to starting maintenance A. NOTIFY Operations prior to beginning work
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B. C. D. E. F.
ENSURE an appropriate clearance/tag out is in place to perform work safely ENSURE all parts expected to be used are available and in hand ENSURE all tools necessary to perform the job are available ENSURE appropriate personal safety equipment is worn on the job RECORD cubicle number, breaker serial number, model, type of overloads and breaker nameplate data.
NOTE Frequency of overhaul for low voltage circuit breakers depends on the environment and operating conditions. Frequency may be between 1 – 3 years depending on conditions. Factors affecting frequency include: high humidity, high ambient temperature, dusty or dirty atmosphere, corrosive atmosphere, frequency of switching operations, frequency of fault operations, and age of equipment. 4.1 Initial Testing and Inspections A. (If installed) VERIFY breaker is open and closing springs discharged. NOTE Do not use excessive force when racking out breaker.
B. CHECK for smooth roller operation during breaker removal. NOTE Use appropriate lifting device to remove breaker from cubicle.
CAUTION Voltage will be present at switchgear bus stabs.
C. REMOVE breaker from cubicle. NOTE Draw out interlocks vary by vendor (Most common are listed)
D. CHECK drawout device interlocks (if installed) a. Racking mechanism (levering) interlock
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b. Trip Interlock c. Manual Lockout device check d. Closing spring interlock e. CONNECT, TEST, DISCONNECT, REMOVE interlocks E. INSPECT the general condition of the breaker. a. Dirt, dust b. Grease hardening, darkening c. Cracking d. Melting e. Burn marks f. Broken, bent, missing parts a. Corrosion F. REMOVE Arc chutes a. Burning b. Cracks G. INSPECT Pole unit bases a. Dirt b. Carbon Tracks c. Cracks 4.2 Mechanical/Electrical Operation
NOTE If breaker has a undervoltage (UV) device it must be energized or mechanically defeated. A. MANUALLY CYCLE breaker several times and check for smooth operation. B. CHECK operation of breaker indicators and breaker operation counter. C. ELECTRICALLY CYCLE breaker and check for smooth operation and excessive arcing in electrical devices.
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4.3 Contact Inspections and Adjustment CAUTION Some tests in this section require opening and closing of breaker. Ensure hands, test instruments and cables and other devices are clear of moving parts. A. INSPECT breaker contacts a. Cracking b. Burning c. Heat stress d. Excessive scarring/galling e. Corrosion f. Pitting g. Discoloration (Over heating) h. Silver plating for flaking or peeling i. Repair or replace any damaged or degraded components j. Measure contact tips for wear (replace if less than vendor recommendation) NOTE Refer to vendor specification for contact gap.
CAUTION If gap adjustments are required care should be taken not to over adjust. Over adjusting will increase closing force B. Gap Adjustments a. Contact gap – MEASURE and adjust as required (As per vendor technical manual) b. Contact sequence gap – MEASURE and adjust as required (As per vendor technical manual)
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4.4 Operating Mechanism Inspection A. INSPECT operating mechanism a. General cleanliness (dirt, dust, corrosion, etc) b. Loose, broken parts c. Loose, missing retainers, snap rings, etc d. Wear and binding in mating surfaces e. Latch and roller surfaces for wear
CAUTION Tests require opening and closing of breaker. Breaker contacts open quickly. Ensure hands and equipment are clear of moving parts.
f. Trip bar or shaft 1. Freedom of movement 2. Determine trip force g. CHECK Operating mechanism alignment h. CHECK Arc contact alignment i. CHECK tripping load
4.5 Electrical Tests
NOTE 1. Refer to vendor manual for electrical devices installed and to be tested. 2. Refer to vendor manual to acceptance criteria.
CAUTION Do not measure insulation resistance of a solid state Over Current Trip Device (OCTD).
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A. MEASURE Primary circuit insulation resistance (Line to Load, Phase to Ground, Phase to Phase) B. MEASURE Control Wiring insulation resistance C. MEASURE Contact resistance (Each phase) D. MEASURE Undervoltage (UV) Device Pickup E. CHECK Control Circuit F. CHECK Shunt Trip Device
NOTE Overcurrent device may be electro mechanical or solid state. G. CHECK Overcurrent Trip Device a. Long time delay b. Short time delay c. Instantaneous d. (If installed) Ground fault test e. NOTE Breaker disassembly differs by breaker and vendor. Refer to vendor manual for specific disassembly information.
4.6 Disassembly A. B. C. D. E.
Primary disconnects Secondary disconnects Frame assembly – charging motor, closing springs, trip shaft/bar Pole unit bases Contact structure – stationary, moving contacts
NOTE Not all breakers have the auxiliary components listed. Refer to vendor technical manual for specific components installed on breaker being overhauled.
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F. REMOVE auxiliary subcomponents a. Auxiliary switch b. Control relay c. Closing solenoid (solenoid operated breakers) d. Bell alarm device e. Amptector unit (if installed) f. Anti-pump relay g. Reset micro switch h. Shunt Trip Device i. Undervoltage (UV) Trip Device j. Electric lockout device k. Fuse Trip Device l. Current limiting fuses m. Reverse current trip attachment n. Closing spring release device o. Motor cutoff switch p. Latch check switch G. REMOVE operating mechanism 4.7 Inspections, Tests, Cleaning and lubrication NOTE 1. Parts should be cleaned with an approved cleaning solvent or isopropyl alcohol and clean lint free rags. 2. Damaged or degraded parts below vendor acceptance criteria should be replaced. CAUTION Some older arc chutes contain asbestos. So not sand or attempt repair unless arc material is known.
A. INSPECT/CLEAN arc chutes a. Burns b. Cracked ceramic c. Carbon deposits d. Erosion
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B. INSPECT/CLEAN/LUBRICATE primary disconnects a. Overheating b. Excessive/abnormal wear c. Broken/weak springs C. INSPECT/CLEAN/LUBRICATE secondary disconnects a. Cracks b. Damage around mounting holes c. Move without binding D. INSPECT/CLEAN frame assemblies a. Corrosion b. Bends c. Cracked welds E. INSPECT/CLEAN contact structure a. Contacts for pitting, corrosion, loss of silver plating b. Contact springs for corrosion, damage or excessive heat F. INSPECT/CLEAN pole unit bases a. Cracks b. Burns c. Carbon tracks d. Warping e. Overheating
NOTE During disassembly of the operating mechanism it is recommended that notes, scribe marks and other aids be used to aid in ensuring that the subcomponents (spacers, retainers, bearing, etc. are reassembled correctly.
CAUTION Handle bearings carefully.
G. INSPECT/CLEAN operating mechanism a. Remove components from shaft working from one end towards middle b. Springs – inspect for breaks, cracks, weakness, and other defects. c. Bearings – proper lubrication, freedom of movement d. Latches – Wear, cracks e. Trip bar/shaft – freedom of movement f. Pins – cracks, worn, alignment through linkages D-12
g. Welds – cracks h. General appearance – corrosion i. (If installed) Levering device – wear, damage
NOTE Not all breakers have the auxiliary components listed. Refer to vendor tech manual for specific components installed H. INSPECT auxiliary subcomponents a. Auxiliary switch 1. CHECK for proper operation 2. CHECK insulation for cracks, discoloration or other defects 3. MEASURE contact resistance 4. DISASSEMBLE and clean switch 5. REPLACE contacts if badly burned or pitted 6. REASSEMBLE switch b. Closing solenoid (solenoid operated breakers) 1. INSPECT coil 2. MEASURE coil resistance INSPECT/DISASSEMBLE/CLEAN Control Relay 1. INSPECT for freedom of movement 2. INSPECT insulation for cracks, discoloration or other defects 3. DISASSEMBLE/CLEAN coil 4. INSPECT coil for signs of overheating 5. MEASURE coil resistance 6. INSPECT plastic components for cracks 7. INSPECT control relay arc chutes (cracks, erosion, carbon deposits) 8. INSPECT plunger core for distortion or warping 9. INSPECT contacts for burning and pitting 10. MEASURE contact resistance b. INSPECT/DISASSEMBLE/CLEAN Shunt trip device 1. INSPECT for freedom of movement 2. INSPECT insulation for cracks, discoloration or other defects 3. DISASSEMBLE/CLEAN coil c. DISASSEMBLE/CLEAN coil Inspect Wiring and connections 1. Cracks/brittleness 2. Pinched wires 3. Broken wires 4. Loose connections 5. Broken lugs d. INSPECT/CLEAN phenolic covers, insulated pushrods, etc. 1. Cracks
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e.
f.
g. h.
i.
j.
k.
l.
m.
2. Carbon tracking 3. Dirt/dust/grease INSPECT/DISASSEMBLE/CLEAN Undervoltage (UV) device 1. INSPECT for freedom of movement 2. INSPECT for overheating 3. MEASURE UV coil resistance 4. INSPECT latch, latch pin and trip lever for excessive wear 5. INSPECT plunger core for distortion or warping 6. LUBRICATE/REASSEMBLE UV coil INSPECT Electric Lockout device 1. INSPECT for freedom of movement 2. INSPECT insulation for cracks, discoloration or other defects 3. DISASSEMBLE/CLEAN coil 4. INSPECT coil for signs of overheating 5. MEASURE coil resistance 6. INSPECT plunger core for distortion or warping INSPECT Bell alarm device 1. INSPECT for freedom of operation 2. MEASURE contact resistance Primary fuses 1. VERIFY proper type 2. VERIFY proper rating 3. CLEAN outside of fuse Fuse trip device 1. DISASSEMBLE the device 2. INSPECT for freedom of operation 3. REASSEMBLE, LUBRICATE friction points Solid State Overcurrent Trip Device (SS OCTD) actuator 1. INSPECT for freedom of operation 2. MEASURE actuator coil resistance 3. INSPECT plastic components for cracks 4. ENSURE permanent magnet has sufficient strength to hold device in reset position Solid state current sensor 1. INSPECT for overheating 2. INSPECT wiring for cracks and other visible damage 3. CLEAN terminations Electro-mechanical overcurrent trip device 1. INSPECT the device for corrosion, defective parts, missing or defective springs, magnet lamination separation 2. CLEAN the trip device 3. REMOVE and clean reset valve and filter 4. LUBRICATE moving parts CLEAN/INSPECT Anti-pump relay 1. Freedom of operation 2. Contacts – pitting, burns, excessive wear 3. MEASURE coil and contact resistance 4. LUBRICATE friction points
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n. CLEAN/INSPECT Reset Micro switch 1. MEASURE contact resistance o. CHECK Overcurrent trip Switch 1. Freedom of operation 2. Insulation condition 3. Overheating of coil 4. Plastic components – cracking 5. Plunger – distortion 6. Contacts 7. LUBRICATE friction points
4.8 Reassembly NOTE 1. Refer to notes taken during disassembly to aid in reassembly 2. During reassembly frequent checks should be performed to ensure all components installed operate freely without binding. 3. Use a mixture of isopropyl alcohol with molybdenum disulfide for lubricating various components. (Pivot points, bearings, bushings, sliding points, etc) As per approved by vendor technical manual. 4. During any lubrication, old lubricant should be removed prior to applying new lubricant.
CAUTION During reassemble keep hands clear of moving parts
CAUTION Do not allow lubricants to be deposited on latch faces
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CAUTION Do not lubricate Overcurrent devices
A. Operating Mechanism a. LUBRICATE the following components 1. Latch faces 2. Trigger faces 3. Trip pan felt pad 4. Trip bar/shaft pivot points and bearing surfaces 5. Spring charge indicator 6. Cam surfaces 7. Closing spring pins 8. Oscillator bar/bushing b. REPLACE all retainers/fasteners c. INSTALL operating mechanism on breaker platform d. ALIGN and INSTALL closing solenoid assembly e. INSTALL contact structure (Main stationary and moving contacts) f. INSTALL Pole Unit bases g. INSTALL frame assembly – operating mechanism, levering device, closing springs, charging motor, trip shaft/bar, frame rollers
NOTE 1. For a given breaker not all subcomponents will be present based on individual vendor design. 2. Refer to vendor technical manual for installation sequence of subcomponents to prevent interferences. 3. Refer to vendor technical manual for any required specification, measurements or clearances that are required during installation B. INSTALL Auxiliary Subcomponents a. Auxiliary switch b. Control relay c. Closing solenoid (solenoid operated breakers) d. Bell alarm device e. Amptector unit (if installed) f. Anti-pump relay g. Reset micro switch h. Shunt Trip Device i. Undervoltage (UV) Trip Device j. Electric lockout device k. Fuse Trip Device
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l. Current limiting fuses m. Reverse current trip attachment n. Closing spring release device o. Motor cutoff switch p. Latch check switch C. INSTALL primary disconnects D. INSTALL secondary disconnects 4.9 Post overhaul Inspections, Adjustments and Tests A. Mechanical Inspections and Tests CAUTION If gap adjustments are required care should be taken not to over adjust. Over adjusting will increase closing force
CAUTION Tests require opening and closing of breaker. Ensure hands, test instruments and cables and other devices are clear of moving parts.
a. Contact gap – MEASURE and ADJUST as required (As per vendor technical manual) b. Contact sequence gap – MEASURE and ADJUST as required (As per vendor technical manual) c. Operating mechanism – CHECK tripping load, alignment check d. UV Device – CHECK clearances, gap measurement and operation e. Fuse Trip device – MEASURE and ADJUST device f. Shunt Trip device – MEASURE clearance between trip bar and trip lever g. Reverse Current Trip – CHECK operation and armature travel h. CHECK Trip latch overlap i. CHECK Drawout device interlocks
B. Electrical Inspections and Tests
NOTE For megger voltage refer to vendor technical manual.
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CAUTION Do not megger wiring of Solid State Trip Unit a. Wiring insulation resistance measurements (Megger except contacts) 1. MEASURE Primary circuit insulation resistance (Line to Load, Phase to Ground, Phase to Phase) 2. MEASURE Control circuit insulation 3. MEASURE Contact resistance (Multimeter) b. TEST Under Voltage Device – CHECK Dropout and breaker closure c. TEST Control Circuit – CHECK for proper operation d. TEST Shunt Trip Device – VERIFY trip function e. TEST Bell alarm – VERIFY proper operation f. TEST Electric Lockout Device – VERIFY proper operation NOTE If breaker has current limiting fuses these must be removed and test bar installed prior to Overcurrent Trip Device test. CAUTION Refer to vendor technical manual for proper test currents when testing overcurrent trip devices. Excessive test currents will pit contacts.
g. Electro-mechanical Overcurrent Trip Device 1. REMOVE current limiting fuses 2. INSTALL test bar 3. CHECK electro-mechanical overcurrent trip device – Proper operation and travel, long time delay, short time delay, instantaneous trip) 4. ADJUST electro-mechanical overcurrent settings to vendor specification as required. NOTE Depending on Amptector installed it may be necessary to defeat either/both, ground fault elements and discriminator circuits. Refer to Amptector vendor technical manual for SS OCTD unit installed.
h. Solid State Overcurrent Trip Device (SS OCTD) 1. VERIFY settings, wiring and connections 2. CHECK SS OCTD – Proper operation and travel, long time delay, short time delay, instantaneous trip)
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3. ADJUST SS OCTD unit settings to desired specification as per vendor manual i. (If required) MEASURE breaker opening and closing times (electrical operation) NOTE If breaker has current limiting fuses these must be removed and test bar installed prior to Overcurrent Trip Device test.
CAUTION Refer to vendor technical manual for proper test currents when testing overcurrent trip devices. Excessive test currents will pit contacts. 4.10Final Breaker Assembly NOTE Catch debris removed from contacts.
A. REMOVE any debris deposited on contacts form breaker overcurrent testing B. INSTALL arc chutes and insulators C. PERFORM final breaker visual inspection for loose components, damaged wiring, etc. 5.0 Determine PMT and PMT considerations A. MANUALLY OPERATE breaker to verify proper operation during open and close operation. B. VERIFY breaker indications reflect proper status of breaker. C. VERIFY breaker cannot be closed with UV device de-energized. D. CONDUCT electrical testing to confirm no short circuits were created during inspection or maintenance. E. REMOVE all test leads and equipment from breaker. F. INSTALL breaker in cubicle test position G. ELECTRICALLY CYCLE breaker in the test position open and close to verify correct operation H. (If installed) VERIFY any key interlocks or mechanical interlocks are functioning properly I. CLEAN work area J. DISPOSE of any special chemicals or solvents used appropriately K. RETURN unused parts to stores D-19
6.0 Feedback Mechanisms Identify mechanism to provide work order feedback for improvements and errors. A. Perform post job review B. Initiate any corrective action program documents necessary to resolve any problem areas identified. 7.0 References Identify typical references needed to perform the identified work A. B. C. D. E. F.
Breaker Vendor Tech manual Applicable wiring drawings Facility Electrical Safety Manual Material Safety Data Sheets Chemical Control Procedures Foreign Material Control
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E WORK PACKAGE TEMPLATE – MOTOR CONTROL CENTER/LOAD CONTROL CENTER (MCC/LCC) INSPECTION AND CLEANING
1.0 Task Overview 1.1 Component type This work instruction is applicable to 480 volt Load Center Breakers, starters, Motor Control Center/Load Control Center (MCC/LCC) cubicles/cabinets, and buss work and hardware. 1.2 Equipment tag or unique equipment identifier Ensure the unique MCC/LCC identifier or which MCC/LCC breaker identifier is used to designate which MCC/LCC or which MCC/LCC breaker is to be worked on. 1.3 Scope This work instruction provides instructions for the cleaning and inspection of 480 volt MCC/LCC Breakers, starters, MCC/LCC cubicles/cabinets, and buss work and hardware. 1.4 Develop list of know consumable materials to be used A. B. C. D.
Electrical contact cleaner (non-residue) Cleaning brushes (no metal) Clean rags Approved cleaner (non-residue)
1.5 Develop a list of know parts to be replaced A. Light bulbs B. Power and control fuses C. Starter contactor kits 1.6 Special tools A. Analog Multi-meter B. Low resistance Ohm Meter
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C. D. E. F. G.
Electrician’s Tool Box Vacuum cleaner 500 to 1000 volt megger Breaker Lifting device Breaker Rack Out Tool
2.0 Pre-job Brief 2.1 Evaluate potential for generation or equipment risk hazards A. Operations must be notified of impending Load Center Work with sufficient time to place alternate equipment into operation or realign power supplies. 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation A. House keeping at the job site should be maintained to minimize the potential for foreign material from entering the MCC/LCC or associated buss work. B. Work area should be roped off to preclude personnel from entering a potential shock hazard area and temporary storage of removed breaker baskets/buckets. 2.3 Job Safety Analysis, Identifies general and specific hazards A. There are potential hazards of electrical shocks and/or burns whenever working in or around electrical equipment B. Appropriate Personal Protective equipment should be worn to preclude shock or arc flash injuries. (As per Facility Electrical safety Manual, NFPA 70E, OSHA, etc) C. Personnel working on breakers should have received the proper training and be qualified to work on this equipment. D. Use of compressed air is not recommended for cleaning. Compressed air only distributes contaminants to other surfaces. If air is used, remove arc covers from contactors and seal openings to control circuits present. Compressed air should also be dry and free from oil E. Many vendors do not recommend burnishing contacts. The filing of contacts removes the silver finish and shortens useful life. Emory cloth should not be used to burnish contacts.
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2.4 Identify permits required A. Define appropriate Clearance/Tag Out boundary and ensure all planned work activities are with in the identified clearance/tag out boundary. B. Identify if any chemical use permits are required for special chemicals or solvents. (Chemical Control Procedure, Material Safety Data Sheets) C. Transient fire loads should have appropriate permits. 2.5 Identify Environmental Consideration A. Review appropriate MSDS sheets and in-house chemical use procedures for any special chemicals or solvents used. B. Identify reporting limits and requirements for any accidental release of chemicals or solvents to the environment C. Identify and special handling or temporary short-term storage requirements for any specials chemicals or solvents required. 2.6 Identify Operating Experience Review any relevant plant specific or industry related operating experience applicable to the work being performed and the use of the tube cleaning equipment. 2.7 Identify Clearance/Tagout Boundary A. Specific breaker to be clean and inspected B. Control power fuses (if required) C. MCC/LCC supply breaker (If MCC/LCC is being cleaned) 3.0 Contingency Considerations 3.1 Identify potential scope expansion and actions due to scope expansion A. Defective parts identified in breaker inspection B. Defective parts identified during starter inspection C. Defective parts identified during bus work inspection
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3.2 Identify individuals to contact in case certain events occur A. Contact planner if scope growth is identified during work instruction performance B. Contact supervision for any uncertainties with respect to the repair or replacement of worn or damaged parts identified during work instruction performance. C. Contact supervision if any problem is identified that prevents following work instructions D. Contact vendor for any clarification of vendor information or additional vendor assistance is required 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions 3.4 Develop material list for potential contingency and consumable parts A. B. C. D. E. F.
Overload heaters Starter coils Pushbuttons Switches Terminal blocks Complete starter kits
4.0 Detailed Work Instructions Develop work instructions, utilize existing procedures when applicable Provide expected actions in proper sequence for task. Identify Notes and Cautions where needed Prerequisites to starting maintenance A. NOTIFY Operations prior to beginning work B. ENSURE an appropriate clearance/tag out is in place to perform work safely C. ENSURE all parts expected to be used are available and in hand D. ENSURE all tools necessary to perform the job are available E. ENSURE appropriate personal safety equipment is worn on the job NOTE Frequency of maintenance for low voltage circuit breakers depends on the environment and operating conditions. Frequency may be between 1 – 3 years depending on conditions. Factors affecting frequency include: high humidity, high ambient temperature, dusty or dirty atmosphere, corrosive atmosphere, frequency of switching operations, frequency of fault operations, and age of equipment.
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NOTE If breaker has experienced a fault a thorough inspection of the breaker should be performed prior to returning it to service.
NOTE It is cost effect to perform load center cleaning with basket/bucket maintenance.
4.1 Load Center Breaker Clean and Inspect CAUTION Check the line side of the breaker for voltage. If voltage is present use extreme caution.
NOTE If working around energized low voltage equipment appropriate electrical safety equipment should be worn. (e.g. gloves, eye protection)
NOTE If an arc has occurred in the breaker compartment it is possible some organic insulating materials may have deteriorated. (Evidenced by soot, debris or carbon tracks)
A. CHECK incoming line terminals to verify that the equipment is de-energized B. CHECK out-going terminals to ensure no feedback condition exists. C. CYCLE breaker in test position and CHECK for undue noise or vibration that may loosen bolted connections. D. INSPECT the internal condition of the breaker basket/bucket. a. Heat Stress b. Cracking c. Melting d. Burn marks e. Discoloration f. Dirt, dust, debris
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NOTE Use of a vacuum cleaner verses air blowing is preferred. Using air to blow out a Load Center basket/bucket typically moves dust around. Dust may settle inside relays, over current devices or other components with contacts causing overheating or improper operation.
E. CLEAN (Using a vacuum cleaner) out the load center basket/bucket NOTE Limit use of solvent when cleaning to remove grease and contamination to minimize residue buildup. It is recommended that alcohol and Freon not be used as cleaning agents. F. CLEAN inside of basket/bucket using and approved solvent or contact cleaner. WIPE bus bars, insulators, cables, etc. G. INSPECT bucket/basket interior for moisture, condensation build-up or signs of previous wet conditions. H. REPAIR any identified sources showing in leakage. I. INSPECT the bucket/basket interior for any signs of overheating or discoloration. J. INSPECT load center basket/bucket components for any signs of visibly worn, cracked or missing parts. a. INSPECT Breaker for: i. Broken disconnects ii. Bent or damaged interlock arms iii. Missing components iv. Line and load connections for overheating v. Line and load connections for missing or defective parts vi. MANUALLY OPERATE to ensure freedom of movement b. INSPECT Starter i. Wiring ii. Contacts iii. Freedom of movement of electrical contactors c. CHECK Fuses i. Proper size (rating) ii. Proper voltage iii. Fit into clips snuggly with no damage or deterioration iv. If fuses are in a holder, blades fit securely into stabs v. Discoloration vi. Corrosion d. INSPECT Aux contacts i. Burns ii. Discoloration iii. Pitting
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iv. Corrosion v. Resistance checks e. INSPECT Insulators i. Cracks ii. Electrical tracking f. INSPECT Arc chutes i. Chipped or broken components ii. Pitting iii. Burning K. REPAIR or REPLACE any damaged or degraded parts NOTE If desired and Insulation resistance test may be conducted during the wiring inspection.
L. INSPECT internal load center basket/bucket wiring g. Tightness h. Cracked or flaking insulation i. For chafing against metal surfaces during vibration j. Discoloration k. Corrosion l. Broken/cracked lugs m. (If warranted) MEGGER wiring to determine condition of circuit breaker insulation to ground and phase to phase. M. REPAIR or REPLACE and damaged or degraded components. N. CLEAN and INSPECT instrumentation and controls a. Pushbuttons, switches, meters, lights, control devices etc i. Damage (missing/broker parts) ii. Proper ratings iii. Loose connection iv. Deterioration v. Switches move freely and are in good working order O. REPAIR or REPLACE any damaged or degraded components. P. Breaker Operating Mechanism a. CLEAN mechanism b. CHECK for proper alignment of basket/bucket (plume and square) c. INSPECT mechanism for any damage, excessive wear or degraded conditions. (Cracks, loose parts (latches), distortion, missing/broken cotter pins, worn cams, roller surfaces, etc) d. LUBRICATE mechanism with light oil (as approved by vendor technical manual)
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NOTE Use of contact cleaners is not recommended by some vendors because of the potential of sticking on magnetic pole faces. Refer to appropriate vendor manual. Q. Starter Contactor a. b. c. d.
INSPECT starter contacts for excessive pitting or arcing HOLD A phase started contactor CLOSED.(made up state) MEASURE resistance across starter contacts. Reading should be less than 0.005 Ohms (typical reading) NOTE
It is recommended that contacts be replaced in pairs to avoid misalignment and uneven contact pressure. e. IF reading is greater than 0.005 Ohms, THEN REPLACE contacts. f. REPEAT (a – d) for B and C phases R. (If applicable) TEST installed electrical accessory devices. a. Under-voltage device b. Shunt trip c. Over-current device d. Auxiliary switch contacts
4.2 Load Center Switchgear Cleaning and Inspection: A. Prerequisites to performing maintenance a. NOTIFY Operations prior to beginning work b. ENSURE an appropriate clearance/tag out is in place to perform work safely c. ENSURE all parts expected to be used are available and in hand d. ENSURE all tools necessary to perform the job are available e. ENSURE appropriate personal safety equipment is worn on the job B. VERIFY by unique load center identifier that the appropriate load center is being worked and it is appropriately tagged out. C. (If applicable) CHECK all door interlocks for proper operation. D. POSITION each breaker in the load center to the “OPEN” position.
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CAUTION Wear appropriate electrical protective equipment until the bus has been verified deenergized. E. VERIFY load center bus is de-energized (appropriate range multi-meter) F. Breaker to Bus Resistance measurements a. MEASURE A phase from line side of breaker to the bus bar b. RECORD resistance reading (typical less than 0.005 Ohms) c. REPEAT (a – b) for B and C phases d. REPEAT (a – c) for all breakers in the load center NOTE Work from the top of the load center down
NOTE Breakers removed from load center should be temporarily stored in a location that will not impede work or be a safety hazard.
G. REMOVE each breaker basket/bucket. H. TAG each load center breaker basket/bucket as to location in load center it was removed from. I. VACUUM thoroughly each load center cubicle slot to remove dirt and debris from basket/bucket and rear of load center. J. WIPE down the interior of each load center cubicle slot using an approved cleaner NOTE Condensation in conduits or dripping from outside sources is a common cause of failure. K. INSPECT MCC/LCC for any signs of wetness, condensation or leaks. L. SEAL off any identified leaks from conduits and PROVIDE an alternate drain source. CAUTION Do not sand or remove any plating on any bus bar, splice bar or terminal lug.
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NOTE Some vendors do not require any servicing of bus connections for the life of the MCC/LCC. Refer to vendor manual before making any bus changes to bus splice joints. Ensure recommended vendor torque values are used if bus joints are tightened.
M. INSPECT all components in each load center cubical bus bars a. Arcing b. Burning c. Heat stress d. Excessive scarring e. Corrosion f. Pitting g. Cracking h. Discoloration i. Insulating materials j. Repair or replace any damaged or degraded components N. INSPECT rear stabs on cubicle’s basket/bucket a. Arcing b. Corrosion c. Discoloration, overheating d. Pitting e. Missing parts O. INSPECT load center grounding cable P. INSPECT seals and latches on load center rear doors. Q. REPAIR or REPLACE defective or degraded components R. SECURE doors on load center (Prior to energizing the MCC/LCC) S. INSPECT exterior MCC/LCC cabinets for a. Missing screws, bolts, nuts, fasteners, retainers and keepers b. Rust and corrosion c. Unused openings d. Conduits for proper fit, no cracks or leaks e. IF MCC/LCC is composed of multiple cabinets, THEN INSPECT sealer between joints T. REINSTALL each breaker basket/bucket in its proper location. U. ENSURE the handle on each breaker is in the “OPEN” position V. CLEAN outside of load center with vacuum and approved cleaner 5.0 Determine PMT and PMT considerations A. PERFORM electrical testing to confirm no short circuits were created during inspection or maintenance. B. RELEASE clearance/tag out for return to service (Operations) C. CYCLE the breaker in the test position open and close several times to VERIFY correct operation E-10
D. (If installed) VERIFY any key interlocks or mechanical interlocks are functioning properly E. CLEAN work area F. DISPOSE of any special chemicals or solvents used appropriately G. RETURN unused parts to stores 6.0 Feedback Mechanisms Identify mechanism to provide work order feedback for improvements and errors. A. Perform post job review B. Initiate any corrective action program documents necessary to resolve any problem areas identified. 7.0 References Identify typical references needed to perform the identified work A. B. C. D. E. F. G. H. I.
Breaker Vendor Tech manual Applicable wiring drawings Facility Electrical Safety Manual NFPA 70E NEMA Standards Publication No. ICS 2, Annex A (Maintenance of Motor Controllers After a Fault Condition) OSHA Standards – 29 CFR Part 1910 Subpart S - Electrical Material Safety Data Sheets Chemical Control Procedures Foreign Material Control
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F WORK PACKAGE TEMPLATE – LIMITORQUE SMB ACTUATORS NOTE Personnel performing this work instruction should be qualified (properly trained and proficient) on the type of Limitorque actuation being worked. 1.0 Task Overview 1.1 Component type This work instruction is applicable to Limitorque SMB actuators. 1.2 Equipment tag or unique equipment identifier Ensure the unique valve identifier is used to designate which valve actuator is being worked. 1.3 Scope This work instruction provides instructions for cleaning, inspections, and limited setup of Limitorque SMB actuators. 1.4 Develop list of know consumable materials to be used A. B. C. D. E.
Lubricant, limit switch (Mobile 28, Vendor approved) Lubricant, gear case (NLGI Grade 0, Vendor approved) Lubricant, valve stem (Graphite type, Vendor approved) Electrical-type cleaning solvent (e.g. CRC Lectra Clean) Clean lint free rags
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1.5 Develop a list of know parts to be replaced A. B. C. D.
Gaskets Seals Limit switches Torque switch
1.6 Special tools A. B. C. D.
Megger (500V to 1000V range) Multimeter (volt-ohm) Electrician’s toolbox Drill
2.0 Pre-job Brief 2.1 Evaluate potential for generation or equipment risk hazards A. Generation a. Most valve actuator maintenance is performed when the valve can either be isolated during power operations with no effect on generation or during a schedule plant outage. b. If the valve stem is to be lubricated during the maintenance it should be isolated. Proper lubrication requires stroking of valve to access stem threads. B. Equipment Risk/Damage a. Do not lift the operator by the handwheel. b. Do not pull or force the declutch lever up or down. c. Do not engage the declutch lever while the motor is running d. Do not use valve wrenches or cheater bars to operate handwheel e. Do not plug motor – alternate motor starts and stops to open or close the valve more tightly f. Do not pump grease into motor g. Do not pinch wires between switch compartment cover and switch compartment flange C. Do not exceed motor duty cycle. (Refer to vendor manual for number of strokes per hour for either AC or DC operated motors)
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2.2 Identify Foreign Material Exclusion (FME) potential and mitigation A. Performance of this work will open actuator to environment. Appropriate measures should be taken to prevent foreign material from entering the actuator. 2.3 Job Safety Analysis, Identifies general and specific hazards A. Beware of electrical hazards. Power should be removed before working on actuator or opening limit switch compartment. B. There is a potential for high pressure fluid, gas, etc. to be on the valve when performing maintenance. The actuator mounting bolts should not be removed from the valve unless the stem is secured. C. If maintenance is being performed on the actuator while installed on the valve, ensure the valve is not under thrust or torque load. D. Do not remove the spring cartridge cap, housing cover or stem nut from the actuator if the valve is under load. E. Do not use cheater bars, wheel wrenches, pipe wrenches or other devices on the actuator handwheel or declutch lever. F. All MANUAL handwheel engagements must be followed by an electrical valve stroke. G. Do not engage handwheel during maintenance activities unless direct to do so by the work instruction or the supervisor. H. Do not engage the handwheel unless one of the following conditions exists: a. Valve is in the mid position b. Valve is in the open position c. Control switch is NOT in the closed position I. The following actions should be avoided to prevent potential actuator/motor damage a. Do not use oversized motor thermal overloads b. Check limit switch settings and motor direction prior to operating the actuator electrically following maintenance c. Do not force the declutch lever into the motor position. The declutch lever returns to the motor position when the motor is energized. d. Do not depress the declutch lever during motor operation to stop valve travel. e. Eyebolts for lifting actuator should not be left in the actuator during operation. Eyebolts installed during maintenance should only be used to lift the actuator. Do not lift the actuator/gearbox or actuator/valve combinations with only the eyebolts.
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2.4 Identify permits required A. Equipment Clearance Orders B. Chemical Control C. Transient Fire Load Permit (cleaning solvents, oil, grease, rags, etc) 2.5 Identify Environmental Consideration A. Refer to Material Safety Data Sheets (MSDS) for proper handling and disposal of special chemicals (E.g. cleaning solvents) B. Handling and disposal of chemicals (E.g. solvents, oil, grease, etc) should be in accordance with approved chemical control procedures 2.6 Identify Operating Experience Review any relevant plant specific or industry related operating experience applicable to the work being performed. 2.7 Identify Clearance/Tag out Boundary A. B. C. D.
Power to actuator motor (at motor control center) Power to space heaters if powered from other than motor source Isolation valves (inlet and outlet side) of valve being worked Bypass valves around isolation valves (if installed)
3.0 Contingency Considerations 3.1 Identify potential scope expansion and actions due to scope expansion A. Inspections of any components may result in the need to repair or replace components as appropriate. B. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work.
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3.2 Identify individuals to contact in case certain events occur A. Contact planner if scope growth is identified during work instruction performance B. Contact supervision for any uncertainties with respect to the repair or replacement of worn or damaged parts identified during work instruction performance. C. Contact vendor for any clarification of vendor information or additional vendor assistance is required 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions 3.4 Develop material list for potential contingency and consumable parts A. Limit Switch Gear Box 4.0 Detailed Work Instructions Develop work instructions, utilize existing procedures when applicable Provide expected actions in proper sequence for task. Identify Notes and Cautions where needed A. B. C. D. E. F.
NOTIFY Operations prior to beginning work ENSURE an appropriate clearance/tag out is in place to perform work safely ENSURE all parts expected to be used are available and in hand ENSURE all tools necessary to perform the job are available REVIEW and UNDERSTAND the scope of work before the start of any field activities. ENSURE appropriate personal safety equipment is worn on the job
4.1 Preparations NOTE Product information, actuator nameplate and motor nameplate, are located on the actuator. Actuator nameplate is typically located opposite the limit switch compartment. Motor nameplate is located on the motor. A. VERIFY clearance/tag out is correctly in place B. LOCATE and ENSURE proper piece of equipment is being worked per the work instruction
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4.2 External Inspection of Actuator/Valve A. INSPECT external condition of actuator for: a. General damage or degradation 1. Cracks to mounting flange 2. Cracks to yoke 3. Cracks to gearcase b. Broken or missing parts (bolts)
NOTE Slight oil weepage is not a cause for replacing a seal.
c. Shaft penetrations for indications of seal leakage d. Oil or grease leakage from gearcase 4.3 Limit Switch Compartment Inspection NOTE Pull switch cover straight away from actuator to prevent damage to interior electrical components. A. REMOVE switch compartment cover and gasket. B. INSPECT switch compartment for: a. Loose parts b. Foreign material c. Oil, moisture, dirt (clean as required) NOTE Wiring should be routed away from space heaters d. Wiring for damage, brittleness, discoloration e. Wire lugs are secure and properly crimped f. Terminations are tight 4.4 Torque Switch Inspection A. INSPECT contact condition and alignment B. CLEAN contacts with electrical-type solvent cleaner
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C. D. E. F. G. H. I. J.
ENSURE contact mounting screws are tight NOTE as found torque switch setting INSPECT base phenolic material for signs of cracking ENSURE electrical connections are tight ENSURE mounting bolts are tight and in good condition ENSURE dial is properly aligned with actuating link ENSURE dial face is not loose RECORD as left torque switch setting
4.5 Limit Switch Inspection A. INSPECT contact condition and alignment B. CLEAN contacts with electrical-type solvent cleaner NOTES “L” bracket may be bent slightly to achieve proper gap or rotor contact Do not use excessive force to bend “L” brackets
CAUTION Circuit should be de-energized prior to adjusting fingers
C. CHECK “L” bracket tension on “L” brackets that are made-up i. ENSURE gap exists between “L” bracket and contact finger ii. Gap between finger and “L” bracket should be approximately equal to thickness of “L” bracket D. CHECK “L” brackets that are not made-up a. ENSURE contact fingers touch rotor E. ENSURE each limit switch rotor is secure to its intermittent pinion. F. VERIFY clearance between rotor and limit switch frame to prevent excessive rotor drag G. INSPECT phenolic material of finger base for cracks H. ENSURE electrical terminations are tight. I. ENSURE mounting screws are tight. 4.6 Limit Switch Gear Box Grease Inspection A. REMOVE upper limit switch gear box cover and gasket
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NOTES Lubricant should be reddish to rust brown. Lubricant viscosity should be soft to slightly fluid 1. Lubricant should not contain dirt or other contaminants B. ENSURE lubricant level is just above the top of the small gears. C. ADD lubricant (e.g. Mobile 28) to proper level as required. NOTE If lubricant was added to the top of a four train switch, lubricant in lower gear box and cartridge assembly must be inspected. D. INSPECT cover gasket and replace as required. NOTES Gasket should not protrude under finger base mounting surface. Trim as required Do not over tighten cover mounting screws. E. INSTALL gear box gasket and cover 4.7 Motor Termination inspection A. INSPECT motor terminations for overheating and degradation 4.8 Install Limit/Torque Switch Compartment Cover A. B. C. D.
CLEAN gasket seating surfaces on compartment and compartment cover INSPECT compartment cover gasket (Clean or replace) APPLY a light coat of bearing grease on compartment/cover surfaces ENSURE wires in switch compartment are routed away from moving parts and space heaters CAUTION
Care must be taken not to pinch any wires between compartment cover and compartment flange.
E. INSTALL switch compartment gasket and cover
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4.9 Main Gearcase Lubrication Inspection A. REMOVE pipe plugs on main gearcase and if available one on the motor pinion compartment NOTE Grease layer at port opening should be cleared so a representative sample can be taken. B. EXTRACT a representative grease sample from the worm gear and the motor pinion gear area. C. INSPECT grease samples for contaminants. (dirt, metal particles, water, etc) D. IF lubricant contains dirt, water or other foreign material THEN: i. FLUSH actuator with a degreaser/cleaner (e..g. Exxon Varsol #18) ii. REPACK actuator with proper lubricant (e.g. NLGI-0 grade) to proper level NOTE If lubricant must be must be added to achieve proper level then: 1. Main gearcase should be filled to a level that covers the worm gear. 2. Main gearcase void should be approximately 20-25% to allow for thermal expansion. 3. Motor pinion compartment should be filled to a level that covers the motor pinion gear. 4. Motor pinion compartment void should be approximately 40-50% to allow for thermal expansion. 5. Ensure lubricant added is the same type lubricant currently in the actuator. Do not mix lubricants in the actuator. E. F. G. H. I. J. K.
ADD lubricant to proper level in the main gearcase. (If required) ADD lubricant to proper level in the motor pinion compartment. (If required) GREASE the housing top flange and handwheel grease zerk fittings. ENSURE grease relief tube is clean and free of grease (If installed) INSTALL pipe plugs removed on main gear case and motor pinion compartment. CLEAN and INSPECT declutch shaft and handwheeel shaft areas. LUBRICATE the declutch and handwheel shaft. CAUTION
To stoke valve it must be isolated from process stream so that process stream is not purtubated during the lubrication process.
4.10 Valve stem lubricant Inspection
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CAUTION If valve is stroked by hand, it must stroked electrically when power is restored prior to returning valve to service.
A. STROKE the valve as required to allow for thorough stem cleaning, inspection and lubrication. B. VERIFY that the Locknut is tight and properly staked. C. CLEAN and INSPECT all accessible portions of the valve stem threads. D. APPLY a thin coat of lubricant (e.g. Graphite type) Threads should appear slightly wet. E. CLEAN and INSPECT the stem nut area. F. VERIFY stem nut is tightly secured by the locknut. G. APPLY a thin coat of lubricant to accessible threads in the stem nut area. 4.11 Motor Inspection A. INSPECT motor leads for signs of overheating, cracked insulation, loose wires or other damage/defects that would prevent proper operation. NOTE AC motors should be meggered at 1000V. DC motors should be meggered at 500V.
CAUTION Limit switch cover should be installed prior to performing a megger on the motor.
B. MEGGER the actuator motor from the Motor Control Center (MCC). C. ENSURE megger reading meets acceptance criteria. (Typically greater than 1 Megohm is normal, Reference vendor tech manual) NOTE Phase to Phase resistance readings should be the same. D. CHECK phase to phase resistance of the motor windings. E. (DC motors) CHECK armature brushes for proper contact and wear
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4.12 Switch Adjustments 4.12.1 Setting the Limit Switch
NOTE The following can be used to set either a Two-Train or a Four-Trained Geared Limit Switch Each drum switch may be adjusted independently of the other(s)
CAUTION If limit switch gear box is damaged or defect, replace the entire gear box. Do not repair limit switch gear box.
A. VERIFY power is off. NOTE After valve is stroked by hand, it must stroked electrically when power is restored prior to returning valve to service. Note direction of Intermittent Gear Shaft for rotor to be set. B. C. D. E.
MANUALLY OPEN valve to the full open position TURN Set Rod clockwise (CW) until it reaches the stop position. The contacts on the Rotor to be set should be in the open position. IF the contacts on the Rotor to be set are not in the open position THEN a. TURN the Intermittent Gear Shaft in the direction noted during the performance of Step B (above) until the Rotor turns and opens the contacts to be set. b. The rotor is set at the correct position for contact opening. F-11
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G. H. I. J.
c. GO to Step G. IF the contacts on the Rotor to be set are already in the open position THEN a. TURN the Intermittent Gear Shaft in the OPPOSITE direction noted during performance of Step B (above) until the Rotor turns and the contacts close. b. TURN the Intermittent Gear Shaft in the direction noted during the performance of Step B (above) until the Rotor turns and the contacts open. c. The rotor is set at the correct position for contact opening. BACK OFF Set Rod until it stops ENSURE that the Intermittent Gear Shaft is tight and will not rotate. Do not force. MANUALLY CLOSE the valve to the full close position. PERFORM steps (C – H) to set the tripping position on the other rotor.
4.12.2 Setting the Torque Switch
NOTE Torque settings must be made with the switch mounted in the actuator.
CAUTION Do not attempt to remove either the spring cartridge cap or the housing cover from the actuator while the valve is torque seated.
4.12.3 SMB-000 Double Torque Switch
A. VERIFY power is OFF B. LOOSEN Pan Head Screws
NOTE The higher the torque number setting the higher the torque output of the actuator.
C. SET the striker for open or close operation. (Match the edge of the Striker with the desired number) to the desired torque setting D. TIGHTEN Pan Head Screws
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4.12.4 SMB-00 Torque Switch
A. VERIFY power is OFF B. LOOSEN Machine Screw
NOTE The higher the torque number setting the higher the torque output of the actuator.
C. SET the pointer, for open or close direction torque switch, at the desired torque setting D. TIGHTEN Machine Screw
4.13 Replace Stem Nut CAUTION Do not remove the Locknut with the actuator under load or with pressure under the valve.
4.13.1 Stem Nut Removal
NOTE The locknut is typically staked in two places A. LOCATE stakes and spot with a drill. B. REMOVE Locknut C. CLEAN up all metal particles. NOTE If valve is stroked by hand, it must be stroked electrically when power is restored prior to returning valve to service.
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D. MANUALLY ROTATE handwheel to close valve. E. ROTATE Stem Nut for the remainder of the length of the valve stem, when stem nut splines are free from Drive Sleeve.
4.13.2 Stem Nut Installation
A. Installation on Keyed Shaft a. LOWER stem nut onto drive sleeve until Stem Nut is seated b. INSTALL the Key c. INSTALL the Locknut d. STAKE in two places (180 degrees apart) B. Installation on Threaded Shaft a. ROTATE Stem Nut onto the shaft until the Stem Nut splines engage the Drive Sleeve splines b. MANUALLY ROTATE handwheel to the open valve position until the Stem Nut is seated. c. INSTALL locknut d. STAKE the top threads above the locknut in two places (180 degrees apart) 5.0 Determine PMT and PMT considerations A. B. C. D.
RELEASE clearance/tag out ELECTRICALLY STROKE valve to ensure it functions properly open and closed. VERIFY limits are set correctly. IF valve was torque seated THEN a. OPERATE valve electrically to seat the valve b. ENSURE tight shutoff by tripping the torque switch contacts. E. Work site cleanup - CLEAN work area to original pre-maintenance conditions F. DISPOSE of any generated waste products properly. G. RETURN unused parts to storeroom 6.0 Feedback Mechanisms Identify mechanism to provide work order feedback for improvements and errors A. Perform post job review B. Initiate any corrective action program documents necessary to resolve any problem areas identified.
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7.0 References A. B. C. D. E. F.
Industrial Safety Manual Foreign Material Control Procedure Material Safety Data Sheets Chemical Traffic Control Procedure Storage of temporary combustibles (transient fire loads) Vendor Technical Manual
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G WORK PACKAGE TEMPLATE – ELECTROSTATIC PRECIPITATOR NOTE This work instruction contains information regarding cleaning, inspection and limited maintenance on a Dry Electrostatic Precipitator (ESP). This instruction can be used in whole or in part based on the desired work to be performed. The work instruction is based on a generic ESP. Some components may or may not be present on all ESP’s. For some specific inspections and maintenance on some components, refer to the appropriate vendor technical manual.
1.0 Task Overview 1.1 Component type This work instruction is applicable to a dry Electrostatic Precipitator. 1.2 Equipment tag or unique equipment identifier Ensure unique equipment identifier is used to designate which precipitator is being worked. 1.3 Scope This work instruction describes the cleaning, limited preventative maintenance and testing of an ash collecting precipitator. 1.4 Develop list of know consumable materials to be used A. B. C. D. E.
Protective clothing Dust masks Clean rags Duct tape Solvent cleaner (vendor recommended)
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1.5 Develop a list of know parts to be replaced A. B. C. D. E. F. G. H. I. J. K. L.
Electrical cleaner (no-residue type) Lubricant (non-gumming) Transformer oil (vendor recommendation) Door gasket materials Door seals (as required) Emitter Wires Emitter insulator rubber boots Alignment clips Ground straps Cover and plate gaskets Transformer surge protectors Filters
1.6 Special tools
A. B. C. D. E. F. G. H. I. J.
Air monitor Protective clothing, dust masks, eye protection, gloves, hard hat Vacuum cleaner Volt/Ohm Meter (Analog) Amp Meter (Clamp On) Megger Portable lighting Water hose Impact gun Typical mechanic’s tool box
2.0 Pre-job Brief 2.1 Evaluate potential for generation or equipment risk hazards 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation A. For work performed in precipitator, hoppers, flues and ducts foreign material exclusion areas should be established. 2.3 Job Safety Analysis, Identifies general and specific hazards A. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work.
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B. All personnel are responsible for ensuring work is performed per approved procedure or work instruction. C. Never touch exposed internal parts of the control system. Operation of the transformer-rectifier controls involves dangerous high voltage. D. Never use fingers or metal screwdrivers to adjust uninsulated control devices. E. Confined space entry permits and precautions for entry into precipitator or flues F. (If present) Never bypass the safety key interlock system on the precipitator. Only use powdered graphite to lubricate lock system. Never use oil or grease. G. Grounding devices should be used when entering the precipitator, transformerrectifier switch enclosure or bus ducts. Precipitators can hold high static electrical charges, up to 15KV following de-energization. H. Never open a hopper door unless the dust level is verified to be below the door. Level should be verified visually from precipitator upper access. Hot dust can flow like water and severely burn or kill a person standing below the hopper door. I. Protective clothing should be worn when entering a precipitator or hopper. J. Be aware of potential high temperatures when entering a precipitator K. Avoid ozone inhalation. Ozone is a toxic gas that can cause severe illness or death if inhaled in sufficient quantity. Air-line masks should be used when entering the precipitator, flues or stack when ozone is present. Precipitator should be monitored for ozone prior to entry. L. If high levels of carbon are known to exist on the collecting surface or in the hoppers, DO NOT open precipitator doors until the precipitator has cooled below 125 degrees F. 2.4 Identify permits required A. Equipment Clearance/Tag out Orders B. Confined Work Space 2.5 Identify Environmental Consideration A. Special chemicals B. Disposal of materials 2.6 Identify Operating Experience Review any relevant plant specific or industry related operating experience applicable to the work being performed and the use of the tube cleaning equipment. 2.7 Identify Clearance/Tag out Boundary Get a generic Precipitator tag out
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3.0 Contingency Considerations 3.1 Identify potential scope expansion and actions due to scope expansion A. Inspections of any components may result in the need to repair or replace components as appropriate. B. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work. 3.2 Identify individuals to contact in case certain events occur A. Contact planner if scope growth is identified during work instruction performance B. Contact supervision for any uncertainties with respect to the repair or replacement of worn or damaged parts identified during work instruction performance. C. Contact supervision if any problem is identified that prevents following work instructions D. Contact vendor for any clarification of vendor information or additional vendor assistance is required 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions 3.4 Develop material list for potential contingency and consumable parts A. B. C. D. E. F. G. H. I.
Anti-sway insulator bushings Rapper parts Vibrator parts Through bushing insulators Through bushings Transformer knife blades Transformer receiver clips Transformer ground pads Control cabinets fans
4.0 Detailed Work Instructions Develop work instructions, utilize existing procedures when applicable Provide expected actions in proper sequence for task. Identify Notes and Cautions where needed
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4.1 Shutdown for Maintenance A. MAXIMIZE precipitator CLEANUP with full ash removal system and rapper system operation
CAUTION Be careful not to violate any EPA limits. B. C. D. E. F. G. H.
REMOVE TR Sets from service as soon as possible after fuel is stopped. MINIMIZE air flow NOTIFY Operations prior to beginning work ENSURE all parts expected to be used are available and in hand ENSURE all tools necessary to perform the job are available IDENTIFY any grounds on Emitter/Transformers LOCATE and ENSURE proper piece of equipment is being worked per the work instruction
4.2 Pre-maintenance checks (prior to clearance/tag out on precipitator) NOTES 1. Any deficiencies identified should be added to the scope of the work instruction for repair or replacement. 2. Procedure for conducting air-load test should be provided in vendor technical manual. Additional guidance on air load tests may be found in EPRI document, Electrostatic Precipitator Maintenance, Volumes 1 and 2, E213676. 3. Dirty air-load test is optional but may provide indications of potential ash build up areas resulting from poor gas flow or inadequate rapping.
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A. PERFORM dirty air load test NOTES 1. Dirty inspection is primarily for determining location and amounts of ash buildup. It can also be used for the identification of obvious problems for potential scope growth and parts identification. 2. Personnel performing inspection should be careful not to disturb ash buildup. This may cause airborne ash problems as well as lose information causing ash buildup. 3. A pre-job brief should be conducted prior to entry into the precipitator for dirty inspection. 4. Abnormal ash buildup may be indication of poor gas flow or inadequate rapping. 5. Areas identified for high or low gas flow should be evaluated as to whether a fix is required or could be successful.
CAUTION Confined Workspace Permit is required for work in lower precipitator.
CAUTION Air quality shall be monitored and verified safe for entry.
CAUTION Appropriate personal safety equipment shall be worn for entry into the precipitator; hard had, respirator or breathing air, gloves, safety glasses/goggles, etc. B. Dirty Inspection a. VERIFY precipitator is shutdown and a clearance/tag out established to allow entry into the precipitator. b. VERIFY precipitator is cooled down sufficiently to allow personnel to enter safely to conduct a dirt inspection. c. EMPTY hoppers d. REMOVE outer insulator doors e. REMOVE inner doors f. MONITOR air quality of precipitator and ENSURE it is safe to enter.
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NOTE Areas of high/low ash deposits (emitters and collector plates) is a potential indication of poor clearances. g. INSPECT internals for ash buildup (0.25 to 0.5 inches can be normal) h. INSPECT internals for possible scouring (indication of high gas flow) i. INSPECT flow control devices for blockage NOTE Rapper transmission force should shake whole discharge emitter or collector plate. Rappers will not shake loose all ash build up at once. It is normal for small amount of ash to build up until a sufficient thickness is obtained to shake loose. C. VERIFY all rappers and vibrators are functioning (transmission force) D. PERFORM a walkdown of the precipitator internals and RECORD the condition of all internal components. a. Rappers – Boots, rod welds, insulators b. Vibrators – insulators c. Plate buildup – color, consistency, thickness d. Wire buildup e. Plates – hanger bolts, plate supports, mounting bolts f. Wires – hanger bolts, arcing shields, bushings, hangers g. Damaged or broken wires – location, probable cause h. High voltage insulators i. Penthouse insulation j. Inlet/outlet ducts – dust condition. Leaks k. Anti-sway bars – brackets l. Inlet perforated plates m. Duct and vane blowers n. Hoppers – cracks, buildup, divider doors o. Transformer set conditions E. INFORM supervision and planning of inspection results and any additional work outside the scope of the current work instruction.
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4.3 Lower Precipitator Maintenance CAUTION Ensure appropriate Clearance/Tag out is hung for complete precipitator outage work. A. VERIFY Clearance/Tag out in place for precipitator overhaul. CAUTION Confined Workspace Permit is required for work in lower precipitator. B. ROLL Tee’s or brake connections on bottom of hoppers to allow residual ash material to be removed and washed to drains. C. REMOVE and WASH residual ash to drains. NOTES 1. Ensure appropriate protective clothing is worn. 2. Whether to clean the precipitator is an expensive proposition. However, ensuring a properly functioning precipitator is essential to clean plant operations. The ability to perform a detailed assessment of the precipitator depends on the cleanliness of the precipitator. Some considerations for whether to clean or not include: cost, amount of identified or suspected corrosion (especially high sulfur content coal), high arsenic levels in ash, extent of work that needs to be performed on the precipitator (wire change outs, structural repairs, etc) 3. Cleaning can either be done by dry blasting (air or other materials) or water wash down. Either have their advantages and disadvantages. This is at the discretion of the facility. 4. Cleaning should be done from top to bottom. D. CLEAN the interiors of the precipitator, and chevron and outlet ducts. E. ENSURE all ash deposits are removed from emitter curtains, rapper plates, interior components and interior walls. F. ENSURE all foreign material is flushed through the hoppers G. IF further cleaning is required to remove stubborn deposits, THEN CLEAN these areas using scrapers and brushes NOTE At the discretion of the facility a clean air load test may be performed. This test may be helpful in identifying any misalignment problems with emitters and collector plates.
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H. PERFORM clean air load test (if desired, optional) I. PERFORM a detailed inspection of lower precipitator and its internals, repair and replacement of key precipitator components. NOTES Location should be recorded using a map. If reason for emitter wire damage is not determined and corrected it may not be worthwhile replacing broken or damaged wire. Air load readings should identify any potential areas likely to have problems.
J. Emitter Wires: a. INSPECT for any dislodged, broken or missing emitter wires b. INSPECT for any degradation that would cause grounds c. REPLACE all broken emitter wires unless a pattern of consistent failure is identified that has not been corrected d. Electrode frame (if installed) CHECK attachment integrity and attachment shunt strap e. Support insulators (if installed) 1. CHECK alignment 2. CHECK for ash buildup 3. CHECK for electrical tracking 4. CHECK for cracking 5. REPAIR or REPLACE any damaged insulators f. REMOVE any material that would cause grounds K. Collector Plates: a. INSPECT collector plates for bends, bows, cracks, holes etc. b. CHECK for misalignment both “across” and “in” the direction of gas flow c. STRAIGHTEN bent or bowed plates d. PATCH (Weld) plates with cracks or holes e. ENSURE alignment rakes are straight and all welds intact f. REPAIR alignment rakes as required g. ENSURE collector plates are separated by the alignment rakes with proper separation. (separation distance specified by vendor technical manual) h. ENSURE proper clearance between emitter wires and collector plates (as per vendor technical manual) i. MEASURE plate thickness (several places near bottom of outlet flow)
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NOTE If collector plate has been eroded away at clip location, it will be necessary to weld a new clip above or below the eroded area. j. k. l. m.
ENSURE alignments clips are in place on collector plates WELD alignments clips in new areas where plates have been eroded away REPLACE all defective or degraded alignment clips REPAIR or REALIGN the baffle between the collector plates and the wall (appropriate clearance as per vendor manual)
L. Anti-Sway Bushings a. INSPECT “Anti-sway” insulator bushings for degradation (stress cracks, excessive ash buildup, ceramic breaks, ceramic erosion, etc b. REPLACE any degraded “anti-sway bushings. NOTE It is important to identify any air leaks into the precipitator. During operation cold air in-leakage can mix with hot gases and create a corrosive atmosphere. M. CLEAN and INSPECT expansion joints for degradation (cracks, holes, deterioration, etc) N. REPLACE any expansion joints that can not be repaired O. CHECK precipitator “box structure” for overall integrity (holes, erosion, corrosion, etc) P. REPAIR any precipitator “Box structure” degradation. Q. INSPECT all doors, sealing surfaces, gaskets and seals. R. CLEAN doors and sealing surfaces and replace gaskets and seals as required. S. Chevron area a. WASH out chevron area b. INSPECT overall structure including pipes, duct bracing, gussets, turning vanes, perforated plates (holes open, not blocked), etc for degradation, erosion, corrosion excessive dust build up and breakage. c. REPAIR or REPLACE any damaged components T. Inlet and Outlet Ducts a. CLEAN and INSPECT outlet duct leaving precipitator to the exhaust stack for cracks, holes, excessive ash fouling, bent or broken diversion plates, turning vanes, expansion joints, etc. b. ASSESS effectiveness of flow distribution devices c. INSPECT access panels/doors (seals/gaskets) for damage or degradation d. REPAIR or REPLACE any degraded components
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NOTES 1. Hoppers can pose a serious personnel hazard. They should be emptied before inspection activities. 2. Scaffolding may be necessary to perform the inspection. This is costly and presents a safety hazard both during installation and use. CAUTION Do not rely solely on level indication instrumentation to ensure hopper is empty. Visually verify if possible. Tapping on door (hollow ring) may be used.
CAUTION Safety chains/latches should be installed and functioning properly on hopper doors
U. Hoppers a. EMPTY hopper prior to dirty inspection. b. CHECK hopper insulation/lagging c. INSPECT lower hoppers for stress cracks, corrosion, erosion, holes and excessive deposit buildup d. CHECK for unusual ash build up e. CHECK for internal obstructions f. CHECK for signs of air in-leakage g. REMOVE all foreign material from hopper (weights, wires, etc.) h. CHECK valves and connections NOTE There are many types of hopper level indication systems (gamma radiation, sound, capacitance, pressure, differential pressure, temperature, etc) Reference appropriate vendor manual for specific level inspections. i. CHECK hopper level indication system (including indicator lights if installed) j. CHECK hopper doors (seals/gaskets) and poke hole for air leaks or dust discharge k. REPAIR any deficiencies noted from hopper inspection
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4.4 Upper Housing (Tension Insulators and Housings, Emitter/Collector Rapper/Vibrator) NOTE Rapper/vibrators will vary from one facility to another. (Electromagnetic impulse-gravity impulse, electromagnetic impulse- spring assist, electromagnetic vibrators, pneumatic, mechanical tumbling hammer) For specific inspections and repairs, refer to vendor tech manual for installed equipment. General rapper inspection guidelines are provided below. A. Emitter and Collector Plate Rapper Inspections a. INSPECT drive motors b. INSPECT rapper controls c. INSPECT rappers for cracks, shaft rubbing or binding, corrosion, leakage (shaft penetration area) welds, couplings d. INSPECT rapper penetration boot seals (air and/or water leakage) e. INSPECT rapper shaft insulators (in installed) f. INSPECT all rapper ground straps intact (ties rapper rod and housing to ground) 4.5 Penthouse (aka. Coffin, Cans, Doghouse) Insulator compartment inspections
CAUTION Confined Space Entry procedures should be used for entry into penthouse. A. Penthouse general condition inspection a. INSPECT structural integrity of enclosure for cracks, corrosion, holes, etc) b. INSPECT all penetrations for adequacy of seal and corrosion c. INSPECT purge air ducting/access doors (seals/gaskets) for leaks and corrosion d. INSPECT insulation and lagging B. VERIFY equipment in the penthouse is de-energized and Clearance/Tag Out installed C. CLEAN and INSPECT ground straps (strap and hooks clean, not corroded) D. REPLACE defective ground straps E. OPEN penthouse inspection doors F. VERIFY atmosphere is acceptable for entry G. INSTALL safety grounds on de-energized equipment H. RECORD as found condition of penthouse
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I. Through Bushing Insulators a. CLEAN through bushing insulators b. INSPECT insulators for stress cracks, wear, or any other abnormality c. REPLACE degraded insulators J. High voltage bus duct inspection a. ENSURE Bus duct is weather tight b. CHECK grounding jumpers across duct sections installed and tight c. REMOVE HV bus duct inspection cover d. INSPECT duct, insulators, thru bushings, bus, connections, etc e. CHECK Insulators free of any contamination (dust, ash, etc), cracks, chips, electrical tracking f. CLEAN insulators with non-abrasive cleaner if required g. REPLACE any damaged or degraded insulators (also replace insulator gasket) h. INSPECT switches(Disconnect or ground switches if installed) for any corrosion or pitting. i. CLEAN or REPLACE switches as required. j. REMOVE any rust or scaling observed k. IF source of rust or scaling is identified THEN REPAIR. l. INSPECT seals/gaskets on inspection covers m. REPLACE seals/gaskets of inspection covers if damaged or degraded. n. VERIFY duct purge vents (if installed) are not plugged or restricted K. Tension Insulators and Housing a. REMOVE tension housing cover, lagging and insulation and inspection cover b. CLEAN tension insulators and internals with water L. ENSURE all surfaces are clean and dry a. INSPECT housings and tension insulators b. CLEAN inspection cover (remove old gasket material) c. INSTALL inspection cover
NOTE Maintain the integrity of the insulation and lagging. Loss of insulation on the precipitator will result in cold spots and eventually corrode your electrostatic precipitator. d. INSTALL insulation and lagging and cover M. Emitter Housing a. REMOVE emitter housing lagging/insulation and inspection plate b. INSPECT condition of inspection plate, gasket and emitter assembly c. CLEAN high voltage (HV) emitter insulators and internals with water d. ENSURE all surfaces are clean and dry e. INSPECT emitter insulator for stress cracks, breaks and gauling around seal penetration
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f. g. h. i. j. k.
CLEAN and INSPECT emitter vibrator assembly TROUBLESHOOT all defective emitter vibrators REPAIR or REPLACE all damaged emitter vibrators as necessary REPLACE emitter insulator boots CLEAN inspection cover (remove old gasket material) INSTALL emitter housing inspection cover NOTE
Maintain the integrity of the insulation and lagging. Loss of insulation on the precipitator will result in cold spots and eventually lead to corrosion. l. INSTALL insulation/lagging N. Purge Air System a. INSPECT and REPLACE filters as required b. CLEAN fans/blowers, motors (lubrication) heaters, dampers, thermostats, switches, etc c. REPLACE any defective heaters 4.6 Transformer/Rectifier (TR)
NOTE Follow approved procedures with respect to the handling and temporary storage or chemicals used for cleaning. CAUTION Safety considerations for TR maintenance 1. Do not perform any maintenance activities on the TR unit will it is operating 2. Follow all grounding procedures (specified in vendor technical manual) 3. Follow general electrical safe work practices with respect to electrical shock 4. Personnel working on TR unit should be properly trained
CAUTION Prior to any maintenance on the TR set the High Voltage (HV) bushing should be grounded using a ground stick.
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A. CLEAN external surfaces with approved cleaner: a. Transformer b. Bus Duct c. Rectifiers d. Cooling fans e. Transfer switch cubicles CAUTION Do not attempt to service or perform any maintenance on the TR set while it is energized. CAUTION Follow all appropriate grounding procedures
CAUTION Follow general electrical safety precautions to prevent electrical shock. B. Transfer Switch Cubicle inspection and cleaning a. INSPECT interior of transformer switching compartments noting any discrepancies b. CLEAN interior of transformer switching compartments with approved cleaner. c. CLEAN and INSPECT bushings in transfer switch cubicle d. REPLACE any degraded bushings e. CLEAN and INSPECT all knife blades and receiver clips f. REPAIR or REPLACE defective or worn knife blades or receiver clips g. ENSURE transfer switch cubicle door gasket/seal is in good condition h. REPLACE defective gasket/seal i. SECURE transfer switch cubicle
CAUTION Use proper foreign material controls when working around an open transformer. All tools and other items shall be secured by lanyard when working around or inside opening. C. Transformer interior inspection a. REMOVE transformer inspection plate b. CLEAN gasket sealing surface (Discard old gasket) c. VERIFY “high” winding to bushing bolting connection(s) are tight
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d. e. f. g.
VERIFY “low” winding to bushing bolted connection(s) are tight RECORD Oil level OBTAIN an oil sample (approximately a quart) INSPECT oil for suspended debris (silicon fluid is clear, mineral oil is amber) h. REPLACE oil removed to the full level (as per vendor technical manual) i. REINSTALL inspection plate with new gasket.
4.7 Control Cabinets (Emitter Control Cabinets, Rapper Control Cabinets) A. VERIFY control cabinets are de-energized can Clearance/Tag Out is hung.
NOTE Eye protection and dust mask should be used when blowing dust out of cabinets.
B. BLOWOUT (Using low pressure air ~40 psig) cabinets, top to bottom (boards, racks, etc) C. INSPECT cables, wires and terminations. D. REPAIR or REPLACE any damaged cables, wires or terminations. (Insulation is good and terminations are tight) E. CLEAN and INSPECT cabinet fans and filters F. REPLACE degraded or damaged fans and filters G. CLEAN and INSPECT contactors for degradation (overheating, arcing, fly ash fouling, insulation deterioration, looseness, etc) H. HOLDING contactors closed, MEASURE resistance across contacts. I. CLEAN and BURNISH any contacts that do not read 0.0 ohms. J. VERIFY all pushbuttons and hand switches change contact state. K. INSPECT cabinet door gasket/seal for any damage or degradation. L. REPLACE gasket/seal if degradation or damage affect sealing surface. M. CLOSE cabinet and ensure all latches work properly. N. REPAIR or REPLACE damaged latches
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5.0 Determine PMT and PMT considerations A. WALKDOWN precipitator external and internal and ensure all maintenance is complete and precipitator is clear of any foreign material. B. ENSURE all ground straps are removed C. ENSURE all personnel are out of the precipitator. D. ENSURE all access doors, inspection ports and other openings are sealed and closed. E. RELEASE clearance/tag out on precipitator F. ENSURE key interlock system is functioning and all TR’s are properly connected. G. PERFORM an air load test prior to boiler light off to ensure: a. ENSURE no grounds b. ENSURE TR sets are sparking at the same level c. ENSURE there is no need to re-enter precipitator. 6.0 Feedback Mechanisms Identify mechanism to provide work order feedback for improvements and errors A. Perform post job review B. Initiate any corrective action program documents necessary to resolve any problem areas identified. 7.0 References A. B. C. D. E. F. G. H.
Industrial Safety manual Applicable vendor technical manuals (Controls and Precipitator) Confined Space Entry Procedure Foreign Material Control Chemical Control Procedure Material Safety Data Sheets Temporary Storage of transient fire loads EPRI, Electrostatic Precipitator Maintenance Guide, E213676, Volumes 1 and 2
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H WORK PACKAGE TEMPLATE – PULVERIZER OVERHAUL
1.0 Task Overview 1.1 Component type This work instruction is applicable to the overhaul of a Roll Wheel Coal Pulverizer. 1.2 Equipment tag or unique equipment identifier Ensure unique equipment identifier is used to designate which Roll Wheel Coal Pulverizer is being worked. 1.3 Scope
This work instruction describes the disassembly, inspection, and reassembly of a Roll Wheel Coal Pulverizer. 1.4 Develop list of know consumable materials to be used A. B. C. D. E. F. G. H. I. J.
Roll Wheel Hub Oil (as per vendor) Gearbox Oil (as per vendor) Grease (as per vendor) High temp RTV (Red) Molycote Heavy oil Permatex Loctite Timbers Saw Blades for Ceramic Saw
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1.5 Develop a list of know parts to be replaced A. B. C. D. E. F. G. H. I. J. K.
Wear plates (Upper Lower, Roller bracket) Grind Ring Segments Throat Vane Segments Roller Bearing Retainer Bearings Bearing Spacers Seals (Roll air and Oil) O-rings Gaskets Wedge Bold Nuts Plugs for jacking bolt holes (if required)
1.6 Special tools A. B. C. D. E. F. G. H. I. J. K. L. M. N. O. P. Q. R. S. T.
Fork lift with personnel work cage Pulverizer Access/Work Platform Inching Air drive Motor Impact Wrench Oxygen-Acetylene Cutting Rig Electric Arc Welder Grinder Chain Hoists Wire and Nylon Slings Turnbuckle Connecting rods Jacks (to raise pressure frame) (Spring frame jacking assembly) 150 ton jack for Grinding Ring Segment removal Ceramic Saw Pulverizer Portable Hydraulic Power Unit Wheel Assembly Handling Tool Wooden Wedges Torque Wrenches (assorted) Torch and appropriate tips Basic tools from mechanics toolbox
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2.0 Pre-job Brief 2.1 Evaluate potential for generation or equipment risk hazards 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation A. If work is performed inside plenums foreign material exclusion areas should be established. 2.3 Job Safety Analysis, Identifies general and specific hazards A. Pulverizer must be purged and cooled down prior to opening the Pulverizer access doors. B. Confined Work Space procedures must be followed when opening Pulverizer inspection doors and entering the Pulverizer housing. C. All personnel are clear of the Pulverizer prior to using the Air Inching Drive to position the Roll Wheel Assembly D. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work. E. Inspect all hoists, slings and other lifting equipment for ant defects and ensure inspection periods are current prior to use. 2.4 Identify permits required A. B. C. D. E.
Equipment Clearance/Tag out Orders Confined Work Space Foreign Material Exclusion Chemical Control Procedure Material Safety Data Sheets
2.5 Identify Environmental Considerations A. Refer to Material Safety Data Sheets (MSDS) for proper handling and disposal of special chemicals (E.g. cleaning solvents) B. Handling and disposal of chemicals (E..g. solvents, oil, grease, etc) should be in accordance with approved chemical control procedures
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2.6 Identify Operating Experience Review any relevant plant specific or industry related operating experience applicable to the work being performed and the use of the tube cleaning equipment. 2.7 Identify Clearance/Tag out Boundary Need a sample clearance for this piece of equipment 3.0 Contingency Considerations 3.1 Identify potential scope expansion and actions due to scope expansion A. Inspections of any components may result in the need to repair or replace components as appropriate. B. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work. 3.2 Identify individuals to contact in case certain events occur A. Contact planner if scope growth is identified during work instruction performance B. Contact supervision for any uncertainties with respect to the repair or replacement of worn or damaged parts identified during work instruction performance. C. Contact maintenance Supervisor for inspection and determination of grinding ring segments replacement. D. Contact vendor for any clarification of vendor information or additional vendor assistance is required 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions
3.3 Develop material list for potential contingency and consumable parts A. Roller Shafts B. Roll Wheel Tires
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4.0 Detailed Work Instructions Develop work instructions, utilize existing procedures when applicable Provide expected actions in proper sequence for task. Identify Notes and Cautions where needed A. B. C. D. E. F.
NOTIFY Operations prior to beginning work ENSURE an appropriate clearance/tag out is in place to perform work safely ENSURE all parts expected to be used are available and in hand ENSURE all tools necessary to perform the job are available ENSURE appropriate personal safety equipment is worn on the job ENSURE all rigging, hoists, chain falls, slings etc. are available and have been inspected prior to use
4.1 Prerequisites A. LOCATE and ENSURE proper piece of equipment is being worked per the work instruction B. VERIFY Pulverizer is shutdown C. VERIFY Equipment Clearance/Tag Out has been established on Pulverizer to be worked D. VERIFY Pulverizer is purged and cooled down for maintenance E. ERECT Pulverizer/Work platform CAUTION Confined Work Space procedures must be established prior to opening and entering the Pulverizer F. OPEN Pulverizer for maintenance G. VERIFY excess coal is removed from Pulverizer (may use outside vendor to vacuum mill)
4.2 Roll Wheel Assembly Removal A. PERFORM profile reading on the grinding ring segments NOTE Maintenance Supervisor should determine in grindings wheel segments need replacement. B. DELIVER grinding ring segment profile readings to maintenance supervisor H-5
CAUTION Ensure personnel are clear of the Pulverizer prior to using the air driven motor.
C. ROTATE the mill to loosen the wedge bolt in the grinding ring segment D. REMOVE cover cone assembly E. INSPECT gear box cover for corrosive damage
NOTE Hot work permit required for removal of wedge bolt nut keeper bars. F. CUT the keeper bar welds G. REMOVE all wedge bolts and nuts H. INSTALL wedge bolt jack plate CAUTION Ensure personnel are clear of the Pulverizer prior to using the air driven inching motor.
I. ROTATE the grinding ring segment directly under roll wheel assembly NOTES 1. Perform the following steps for each wedge bolt. 2. Turnbuckles are to be installed between the wheels and not across the wheels (as per vendor)
J. K. L. M. N.
INSTALL turnbuckle maintenance fixtures to support roll wheel assembly INSTALL fixture base plate and turnbuckles BOLT base plate to the roller bracket of all three roll wheels REMOVE slack from of turnbuckle linkage INSTALL wood wedges under the roller and between bracket and tire before proceeding O. REMOVE seal air piping for each bracket a. DISCONNECT lower ball joint b. REMOVE piping from mill
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P. Q. R. S. T.
c. INSTALL covers on bracket seal air openings to prevent entry of foreign material. RELEASE spring tension and loading force on hydraulic cylinders REMOVE clevis pins connecting the loading assembly to the spring frame CONNECT spring frame to pressure frame using connecting rods DISCONNECT loading cables INSTALL spring frame jacking assembly CAUTION
Ensure all personnel are clear from inside the Pulverizer before next step. U. ENSURE inside of Pulverizer has been cleared of all personnel (Signoff Required) V. RAISE the pressure frame (using jacking assembly), springs and spring frame as high as possible. W. SECURE spring frame jacking assembly with wire sling and 2 tone chain hoist from eye bolts in ceiling X. REMOVE the roll pivot pins Y. SECURE roll pivot blocks to pressure frame assembly Z. Roll Wheel Assembly Removal For each wheel perform the following REMOVE wear plates from roll wheel INSTALL roll wheel removal assembly (jacks) ATTACH lift bracket to roller bracket ASSEMBLE all jackscrews DISCONNECT turnbuckle assembly OPERATE screw mechanism to pivot roll wheel assembly out of the mill LOWER roll wheel assembly to forklift for temporary storage CAUTION Ensure personnel are clear of the Pulverizer prior to using the air driven inching motor. AA. ROLL Wheel Assembly Removal for the remaining wheels Rotate pulverizer to bring next roll wheel assembly to the door. BB. REPEAT step [Z] and [A] for remaining wheels. 4.3 Grinding Ring Segment Removal and Replacement CAUTION For use of plasma arc cutter, ensure the yoke is grounded to Pulverizer housing.
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CAUTION Do not cut seat ring.
A. GROUND plasma arc cutter yoke to Pulverizer B. CUT the first grinding ring segment into several small pieces C. PRY remaining grinding ring segments loose and REMOVE with segment handling tool D. CLEAN the grinding ring seat surface NOTE If damage is present contact engineering for resolution. E. INSPECT grinding ring seat surface for damage F. CLEAN seating surfaces of new grinding ring segments G. INSTALL first grinding ring segment over the drive dowel pin and ALIGN it with wedge bolt holes NOTES 1. Ensure grinding ring segments are pushed tightly together. 2. Assembled grinding ring segments should align within vendor tolerances on grinding face contour. 3. It may be necessary to grind the bosses of the last several segments to achieve proper positioning H. INSTALL remaining grinding ring segments. NOTES 4. Torque pattern will be per vendor instructions or a standard torque pattern such as 1200, 0600, 0300, and 0900. 5. Torque sequence of wedge bolts and nuts should be as per vendor instructions. 6. Subsequent to 50 hours of Pulverizer operation the Pulverizer should be removed from service and the wedge bolts re-torqued.
I. J. K. L. M.
INSTALL wedge bolts, washers and nuts TORQUE wedge bolts and nuts per vendor recommendation INSTALL keeper bars and tack weld in place to the seat ring INSTALL plugs in jack bolt holes (if required) INSTALL cone cover assembly (use Permatex in the joint)
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NOTE RTV should be used around wedge bolts and dowels to prevent coal dust from entering yoke cavity. N. INSPECT pressure frame wear plates and replace as required. O. INSPECT intermediate housing wear plates and replace as required
NOTE If UT testing of seal air piping header is desired, this must be done before wheels are re-installed. P. PERFORM UT testing of seal air piping if required Q. INSPECT seal air piping seals and replace as required 4.4 Roll Wheel Assembly Installation A. INSTALL top turnbuckle brackets in place on wheel brackets B. INSTALL bottom turnbuckle fixture brackets on cone cover plate
NOTE Do not remove assembly from the removal bracket mechanism at this time. C. INSTALL first roll ring assembly on the grinding ring and center it on a fixture.
NOTE Turnbuckles are to be installed between the wheels and not across the wheels (as per vendor) D. ASSEMBLE turnbuckles to the roller bracket E. INSTALL wooden wedges under wheel to prevent the wheel from rolling F. LEVEL the top of the removal bracket along the centerline of the pivot pins to the center of the mill G. CONNECT turnbuckle assembly to wheel assembly H. DISCONNECT roll wheel assembly from removal tool I. INSTALL roll wheel bracket wear plates
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CAUTION Ensure personnel are clear of the Pulverizer prior to using the air driven inching motor. J. ROTATE Pulverizer (using inching air drive motor) until the next wheel’s assembly is located at the maintenance hatch. K. REPEAT above steps for all roll wheel assemblies L. INSPECT roll pivot pins and pivot blocks. Replace if wear is severe. M. ASSEMBLE roll pivot in the wheel brackets for each roll wheel. NOTE It may be necessary to position the wheel assemblies under pressure frame blocks.
CAUTION Ensure all personnel are clear from inside the Pulverizer before next steps.
N. ENSURE inside of Pulverizer has been cleared of all personnel (Signoff Required) O. LOWER pressure frame, springs and spring frame onto roll wheel assemblies. P. POSITION the wheel assemblies under the pressure frame blocks just prior to contact. Use turnbuckles and inching air drive motor to position. Q. LOWER pressure frame while aligning pivot blocks and pivot ring R. INSTALL seal air piping SLIDE piping into upper joint ATTACH lower ball joint S. CONNECT loading assembly to the spring frame using clevis pins T. PRESSURIZE hydraulic cylinders to remove slack from loading cables U. REMOVE turnbuckle assemblies.
NOTES 7. Proper spring loading should be at vendor manual requirements. 8. Hydraulic cylinder loading and spring height should be recorded for future reference. V. W. X. Y.
PRESSURIZE the hydraulic loading cylinders to obtain proper spring loading. MEASURE spring height at various locations RECORD hydraulic cylinder loading and spring height TIGHTEN top and bottom nuts on loading cylinders
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Z. TIGHTEN top lock nuts on loading cylinder AA. RELEASE loading hydraulic pressure BB. REMOVE turnbuckle assemblies CC. GREASE wheel assembly seals DD. CHECK oil level in each wheel assembly 4.4 Final Reassembly A. B. C. D. E. F. G. H.
RELEASE Clearance/Tag out on seal air system CHECK seal air system for leaks CLOSE maintenance hatch and other openings on Pulverizer. REMOVE Pulverizer/Work platform RELEASE Pulverizer/Tag Out on Pulverizer STORE tools used for work CLEAN work area to pre-work conditions RETURN unused part to stores
NOTE If work was performed inside a plenum ensure are materials taken into plenum have been removed.’ I. INSTALL guards, covers and access ports 5.0 Determine PMT and PMT considerations Looking for post maintenance information 6.0 Feedback Mechanisms Identify mechanism to provide work order feedback for improvements and errors A. Perform post job review B. Initiate any corrective action program documents necessary to resolve any problem areas identified. 7.0 References A. B. C. D.
Industrial Safety manual Confined Work Space Procedure Applicable vendor technical manuals Foreign Material Control
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I WORK PACKAGE TEMPLATE – DAMPERS 1.0 Task Overview 1.1 Component type This work instruction is applicable to various dampers. 1.2 Equipment tag or unique equipment identifier Ensure unique equipment identifier is used to designate which damper is being worked. 1.3 Scope This work instruction describes inspection, cleaning, lubrication and minor maintenance of dampers. 1.4 Develop list of know consumable materials to be used A. B. C. D. E.
Clean lint free rags Grease (e.g. Mobilux EP #2, vendor approved) Cleaning solvent (Vendor approved) Brush Oil (Vendor approved)
1.5 Develop a list of know parts to be replaced A. Gaskets B. Seals C. Packing
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1.6 Special tools A. B. C. D. E.
Mechanic’s tool box Grease gun Can oiler Ladders, scaffolding (depending on location) Safety belts
2.0 Pre-job Brief 2.1 Evaluate potential for generation or equipment risk hazards A. Some fans have resonant frequencies. Belts should be adjusted appropriately to avoid fans potentially running at resonant frequencies. B. Some belts do not recommend the use of belt dressings. This could cause premature belt failure. (refer to belt manufacture with respect to belt dressings) C. It is recommended that belt tension be checked within 24 to 48 hours of installing new belts due to belt break-in stretch. D. If ventilation fans are being worked, resulting ventilation line-ups to support work can cause significant d/p’s across doors or other accesses posing a personnel safety hazard. 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation A. If work is performed inside plenums foreign material exclusion areas should be established. 2.3 Job Safety Analysis, Identifies general and specific hazards A. Conduct a pre-job brief to ensure the scope of the work to be performed is understood by all personnel. B. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work. 2.4 Identify permits required A. Equipment Clearance/Tag out Orders B. Chemical Control Procedures (handing and disposal)
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2.5 Identify Environmental Consideration A. Refer to Material Safety Data Sheets (MSDS) for proper handling and disposal of special chemicals (E.g. cleaning solvents) B. Handling and disposal of chemicals (E..g. solvents, oil, grease, cleaning materials, etc) should be in accordance with approved chemical control procedures 2.6 Identify Operating Experience Review any relevant plant specific or industry related operating experience applicable to the work being performed and the use of the tube cleaning equipment. 2.7 Identify Clearance/Tag out Boundary A. Motive force to damper (breaker, air supply) B. Power to FD or ID fan(s) 3.0 Contingency Considerations 3.1 Identify potential scope expansion and actions due to scope expansion A. Inspections of any components may result in the need to repair or replace components as appropriate. B. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work. 3.2 Identify individuals to contact in case certain events occur A. Contact planner if scope growth is identified during work instruction performance B. Contact supervision for any uncertainties with respect to the repair or replacement of worn or damaged parts identified during work instruction performance. C. Contact vendor for any clarification of vendor information or additional vendor assistance is required 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions
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3.4 Develop material list for potential contingency and consumable parts A. Bearings B. Shaft 4.0 Detailed Work Instructions Develop work instructions, utilize existing procedures when applicable Provide expected actions in proper sequence for task. Identify Notes and Cautions where needed A. B. C. D. E.
NOTIFY Operations prior to beginning work ENSURE an appropriate clearance/tag out is in place to perform work safely ENSURE all parts expected to be used are available and in hand ENSURE all tools necessary to perform the job are available ENSURE appropriate personal safety equipment is worn and used on the job
4.1 Inlet Damper Clean/Inspection A. DISCONNECT damper linkage from actuator. NOTE Reference vendor technical manual for approved cleaning methods: steam clean, water wash, sandblast, approved solvents
B. CLEAN blades and linkage(s) using vendor approved method of: a. Dirt/dust/ash/etc b. Old grease NOTE Any damaged or degraded components should be evaluated for replacement. Work instruction should be amended to perform corrective maintenance. C. INSPECT the damper components: a. INSPECT linkages for: 1. Inadequate lubrication 2. Verify free of obstruction or binding 3. Missing or broken parts (pins, bolts, fasteners, etc) 4. Proper alignment b. INSPECT blades for:
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1. 2. 3. 4. 5. 6. 7. 8. 9.
Corrosion Erosion Ash buildup Cracks Warpage Seal along blade edges Binding Bending/buckling Brittle/broken frayed seals (If installed on blades) NOTE
Seals (if installed) may be either metallic, silicone, rubber or plastic). Seal tightness may be checked by a smoke test.
c. INSPECT blade seals 1. INSPECT in open and close position for straightness and obvious surface variations. 2. ENSURE blade seals provide continuous contact along entire blade length in the closed position. d. INSPECT blade shaft 1. INSPECT shaft at bushing or bearing pint for wear 2. INSPECT for bowed shaft e. INSPECT frame for: 1. Corrosion 2. Erosion 3. Warpage that may cause blade binding f. INSPECT packing glands for leakage 1. Repack glands as required g. CLEAN accessible external surfaces of the damper unit h. CHECK damper mountings for loose, broker or missing parts i. INSPECT ductwork to damper seals for tightness CAUTION If inside of ductwork at damper is inspected for ash buildup CONFINED WORKSPACE requirements should be in effect.
j. INSPECT inside portion of ductwork at damper for ash build up.
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4.2 Damper Bearings A. REMOVE damper bearing(s) NOTE 1. Soak sufficiently to loosen and remove grease/dirt 2. Use a brush to assist in removal of grease/dirt B. CLEAN bearing(s) by soaking bearing(s) in approved solvent to remove grease and dirt C. SLOWLY ROTATE outer race noting any rough/sticky spots NOTE If rough/sticky spots persist after repeated cleaning attempts the bearing should be disassembled and inspected.
D. DISASSEMBLE bearing. E. INSPECT bearing for damage. NOTE If any of the following conditions exist, replace bearing.
a. b. c. d. e. f. g.
Broken or cracked rings Dented shields/seals Cracked/broken separators Broken/cracked balls or rollers Flaked/spalled areas on balls, rollers or raceways Discoloration (brownish blue or blue-black areas) Indented/brinelled/etched raceways
4.3 Lubrication A. LUBRICATE linkages B. LUBRICATE bearings C. APPLY small amount of oil to all damper moving components
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4.4 Reassembly A. B. C. D.
INSTALL bearings (if removed) INSTALL linkages (if removed) INSTALL all bolts, screws and fasteners (torque as specified) MANUALLY CYCLE damper open and closed and INSPECT for: a. Smooth operation of linkage and blades b. Check for any binding or noise c. Check completeness of travel d. Check mechanical stops E. INSTALL guards, covers and access ports F. INSTALL linkage to actuator G. SET Mechanical stops and electrical limits 5.0 Determine PMT and PMT considerations A. RELEASE Clearance/Tag out on damper B. ELECTRICALLY CYCLE damper open and close and INSPECT for: a. Proper operation of linkage and blades b. Unusual noise c. Vibration d. Proper setup of mechanical stops and electrical limits NOTE Damper synchronization is accomplished by establishing a reference dimension, actuating the vanes, and comparing the two sides for balance. C. VERIFY that dampers are synchronized, for double inlet or outlet damper configurations. D. DISPOSE of any generated waste products properly. E. RETURN any unused spare parts to stores/warehouse
6.0 Feedback Mechanisms Identify mechanism to provide work order feedback for improvements and errors A. Perform post job review B. Initiate any corrective action program documents necessary to resolve any problem areas identified.
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7.0 References A. B. C. D. E.
Industrial Safety Manual Damper vendor technical manual Actuator vendor technical manual Material Safety Data Sheets Chemical Traffic Control Procedure
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J WORK PACKAGE TEMPLATE – CENTRIFUGAL PUMP (PROCESS, 3196) NOTE Personnel performing this work instruction should be qualified (properly trained and proficient) on the type of pump being worked.
1.0 Task Overview 1.1 Component type This work instruction is applicable to a typical centrifugal process pump. (E.g. Gould 3196 ST, MT, STX, MTX). A typical Model 3196 STX pump is shown in Figure J.4 in the reference section of this template. 1.2 Equipment tag or unique equipment identifier Ensure the unique pump identifier is used to designate which pump is being worked. 1.3 Scope This work instruction provides instructions for inspection and repair of a centrifugal process pump. 1.4 Develop list of know consumable materials to be used A. B. C. D. E. F. G. H. I.
Acetone Isopropyl alcohol Varsol Clean lint free rags Grease (e.g. Koppers KHP) Pump bearing oil (E.g. MO-2) Silicone grease (E.g. Molycote 55 or 44, Dow Corning 4 or 111) Oil Drain pan Duct tape
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J. Containers (E.g. bags) for temporary storage of parts 1.5 Develop a list of know parts to be replaced A. B. C. D. E.
Gland Gasket Impeller O-Ring Bearing Housing O-Ring Casing Gasket Bearings
1.6 Special tools A. B. C. D. E. F. G. H. I. J. K. L. M. N. O.
Mechanics tool box (wrenches, screwdrivers etc) Bearing puller Bearing driver Snap ring pliers Rubber mallet Torque wrenches (various) Allen wrenches Dial indicator Micrometer (inside and outside) Feeler gauges Pyrometer Sling Jacking screws C clamps Shaft wrench
2.0 Pre-job Brief 2.1 Evaluate potential for generation or equipment risk hazards A. Generation B. Equipment Risk/Damage 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation A. Performance of this work will open pump to environment. Appropriate measures should be taken to prevent foreign material from entering the pump.
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2.3 Job Safety Analysis, Identifies general and specific hazards A. DO NOT allow petroleum based products to contact the EPT O-rings of the mechanical seal. Petroleum based products will cause the O-rings to deteriorate and fail. B. Oil drained from the pump should be removed from the work area and properly disposed of as soon as practical. Other wise, an appropriate transient fire load evaluation should be performed and proper temporary storage provided. C. Follow appropriate Material Safety Data Sheet (MSDS) and site approved procedures for handling and disposal of cleaning chemicals and solvents. D. Follow approved site procedures for proper draining and disposal of process fluids from the pump. 2.4 Identify permits required A. Equipment Clearance Order B. Chemical Control Permit C. Transient combustible material storage permit 2.5 Identify Environmental Consideration A. Refer to Material Safety Data Sheets (MSDS) for proper handling and disposal of special chemicals (E.g. cleaning solvents) B. Handling and disposal of chemicals (E..g. solvents, oil, grease, etc) should be in accordance with approved chemical control procedures 2.6 Identify Operating Experience Review any relevant plant specific or industry related operating experience applicable to the work being performed. 2.7 Identify Clearance/Tag out Boundary A. B. C. D. E. F. G.
Pump suction valve Pump discharge valve Pump recirculation valve Pump Vent valve Pump Drain valve Power to motor If installed (Gland seal supply valve)
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3.0 Contingency Considerations 3.1 Identify potential scope expansion and actions due to scope expansion A. Inspections of any components may result in the need to repair or replace components as appropriate. B. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work. 3.2 Identify individuals to contact in case certain events occur A. Contact planner if scope growth is identified during work instruction performance B. Contact supervision for any uncertainties with respect to the repair or replacement of worn or damaged parts identified during work instruction performance. C. Contact vendor for any clarification of vendor information or additional vendor assistance is required 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions 3.4 Develop material list for potential contingency and consumable parts A. Impeller B. Coupling C. Mechanical Seal 4.0 Detailed Work Instructions Develop work instructions, utilize existing procedures when applicable Provide expected actions in proper sequence for task. Identify Notes and Cautions where needed A. B. C. D. E. F.
NOTIFY Operations prior to beginning work ENSURE an appropriate clearance/tag out is in place to perform work safely ENSURE all parts expected to be used are available and in hand ENSURE all tools necessary to perform the job are available REVIEW and UNDERSTAND the scope of work before the start of any field activities. ENSURE appropriate personal safety equipment is worn on the job
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4.1 Preparations A. VERIFY clearance/tag out is correctly in place B. LOCATE and IDENTIFY proper piece of equipment is being worked per the work instruction C. ENSURE piping, equipment supports, and other interferences are removed to support work. D. IF installed, THEN REMOVE insulation. 4.2 Preparation for pump removal A. REMOVE coupling guard.
NOTE For disc type couplings ensure disc sequence is maintained during removal Either leave a bolt in one bolt hole or tape disc pack to maintain proper sequence.
B. DISASSEMBLE coupling C. IF coupling contains grease, THEN CLEAN grease from coupling. D. IF required to drain pump casing, THEN DRAIN casing. NOTE Cover exposed ends of pipe to prevent entry of foreign material.
E. IF installed, THEN REMOVE gland seal supply and leakoff piping. F. IF pump had constant level oiler, THEN REMOVE and DRAIN oiler bulb. NOTE After draining oil remove from area and properly dispose of or provide temporary combustible storage. G. DRAIN oil from pump.
H. REMOVE frame foot hold down bolts. I. REMOVE pump from casing. e. REMOVE casing bolts f. REMOVE casing gasket
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NOTE Shims that are removed should be marked so they can be replaced in their original positions.
NOTE Sling should be used to support pump during removal from casing. Jack screws should be used to back out pump from casing. g. REMOVE pump from casing. h. COVER open casing (Foreign Material Exclusion) NOTE Use proper lifting or rigging practices to remove pump from location to work area. J. MOVE pump to maintenance location.
4.3 Pump Disassembly A. SECURE pump frame to workbench NOTE Coupling hub position should be marked on shaft B. C. D. E.
REMOVE coupling hub. REMOVE impeller from shaft (Impellers are screwed on) REMOVE impeller O-ring IF pump has a packing stuffing box, THEN REMOVE split gland and stuffing box cover. NOTE
Mechanical seal location should be marked on shaft F. IF pump has a mechanical seal, THEN REMOVE mechanical seal. G. IF installed, THEN REMOVE frame adapter. NOTE Disassembly of the power end and it components varies with model. Refer to vendor technical manual for specific installation.
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H. REMOVE bearings as follows i. REMOVE bearing housing bolts j. REMOVE (As a unit) shaft, bearings and bearing housing k. REMOVE inboard bearing using a bearing puller. l. REMOVE bearing housing from shaft m. REMOVE outboard bearing I. REMOVE inboard and outboard oil seals J. IF pump has a packed stuffing box, THEN REMOVE packing rings from stuffing box. 4.4 Pump Inspection NOTE Age of bearings, mechanical seals, gaskets and O-rings should be taken into account as to whether they should be replaced regardless of inspection results. A. CLEAN pump parts as required using isopropyl alcohol or acetone B. REMOVE burrs as required. NOTE Refer to vendor technical manual for acceptable tolerances C. VISUALLY INSPECT parts for corrosion, erosion or wear. a. Casing (grooving, pitting) b. Frame adapter (cracks, gasket surface) c. Impeller (grooving, pitting, cracking) d. Shaft (bearing fit, shaft runout) e. Mechanical Seal f. Bearing frame (cracks, scale, debris, lubrication passages clear) g. Inboard Bearing (contamination, damage, overheating, fit etc.) h. Outboard Bearing (contamination, damage, overheating, fit etc.) i. Casing Bolts (cracks, damaged threads)) j. Mechanical Seal Gland bolts k. Labyrinth seals (O-rings for cuts and cracks) l. Packing studs/nuts (cracks, damaged threads) D. REPLACE all damaged or degraded parts. E. LIST parts replaced in work package. 4.5 Pump Reassembly A. ENSURE bearings are clean and LUBRICATED. B. LUBRICATE bearing location on coupling end of shaft.
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CAUTION It may be necessary to heat the bearing to install it on the shaft. If the bearing is heated DO NOT overheat. Bearing should not be heated more than 250 degrees F. NOTE Bearing may be heated using a bearing heater and installed on the shaft by hand. CAUTION Gloves should be worn when handing hot bearings C. IF heat is used, THEN HEAT and INSTALL outboard bearing on coupling end of shaft until firmly seated on shaft shoulder. NOTE It may be necessary to lightly tap bearing using a pipe or driving sleeve to fully seat bearing against shaft shoulder. D. IF heat is NOT used, THEN SLIDE outboard bearing onto coupling end of shaft until firmly seated on shaft shoulder. NOTE Drain slots should be positioned at bottom for labyrinth seal E. F. G. H.
LUBRICATE and INSTALL oil seal in thrust bearing housing. LUBRICATE and INSTALL O-ring on bearing housing. SLIDE and LOCK bearing housing onto shaft. LUBRICATE bearing location at impeller end of shaft.
CAUTION It may be necessary to heat the bearing to install it on the shaft. If the bearing is heated DO NOT overheat. Bearing should not be heated more than 250 degrees F. NOTE Bearing may be heated using a bearing heater and installed on the shaft by hand. CAUTION Gloves should be worn when handing hot bearings
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I. IF heat is used, THEN HEAT and INSTALL inboard bearing on impeller end of shaft until firmly seated on shaft shoulder. NOTE It may be necessary to lightly tap bearing using a pipe or driving sleeve to fully seat bearing against shaft shoulder. J. IF heat is NOT used, THEN SLIDE inboard bearing onto impeller end of shaft until firmly seated on shaft shoulder.
NOTE Oil seal may be installed in frame adapter or bearing adapter depending on model. NOTE Drain slots should be positioned at the bottom for labyrinth seals. K. INSTALL and LUBRICATE oil seal. NOTE Top of thrust bearing housing should be in line with top of frame. L. M. N. O.
INSTALL bearing and shaft assembly into frame IF pump has a shaft sleeve, THEN INSTALL shaft sleeve on to shaft. INSTALL deflector onto shaft OR shaft sleeve. IF pump has a packing stuffing box THEN a. INSTALL stuffing box cover b. INSTALL impeller O-ring and impeller on shaft NOTE
Refer to vendor technical manual for gap clearance
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c. Temporarily ADJUST gap between impeller and stuffing box. P. IF pump has a mechanical seal, THEN: a. INSTALL stuffing box cover against frame adapter OR bearing frame. b. INSTALL impeller O-ring and impeller on shaft NOTE Refer to vendor technical manual for gap clearance c. Temporarily ADJUST gap between impeller and stuffing box. d. REMOVE impeller and stuffing box cover e. INSPECT mechanical seal, mechanical seal gland and internals of stuffing box cover for cleanliness. NOTE Care should be taken to minimize dust or other contaminants from settling on seal faces until all parts are assembled and locked into final position. f. g. h. i.
LUBRICATE and INSTALL stationary O-ring on seat INSTALL stationary seat in gland INSTALL stationary seat in stuffing box cover SLIDE Gland with gasket over shaft NOTE
Refer to position for mechanical seal marked on shaft during disassembly. j. SLIDE and LOCK mechanical seal into position on shaft k. INSTALL stuffing box cover l. INSTALL impeller O-ring and impeller on shaft NOTE Refer to vendor technical manual for appropriate torque value for gland stud nuts based on size m. SLIDE and TORQUE mechanical seal gland into position
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4.6 Pump Installation NOTE Coupling hub should be positioned at scribe mark made during disassembly A. B. C. D. E.
INSTALL coupling hub on shaft MOVE pump to plant location. INSPECT casing internals for cleanliness. INSTALL casing gasket against casing shoulder. ENSURE jacking bolts are back all the way out. NOTE
Use proper rigging techniques during installation or frame assembly to prevent damage. F. INSTALL frame assembly into casing NOTE If the impeller does not turn freely while tightening the casing bolts, the impeller should be adjusted using the impeller adjusting bolts. G. LUBRICATE and INSTALL the frame-casing bolts. H. TORQUE casing bolts to appropriate vendor specified value. NOTE Shaft should be rotated by hand during torque of casing bolts NOTE Additional shims may be added as required to avoid pipe strain. I. REPLACE shims removed during disassembly J. INSTALL frame foot hold down bolts (Wrench tight) NOTE Impeller clearance may be adjusted by either the Feeler Gauge Method OR the Dial Indicator Method. K. Adjusting impeller clearance by Feeler Gauge method J-11
Figure J.1 Impeller Adjustment – Feeler Gauge Method
a. LOOSEN locknuts on impeller adjustment bolts. b. LOOSEN impeller adjustment bolts several turns. c. Evenly TIGHTEN bearing housing bolts, while slowly rotating pump shaft by hand until impeller just starts to rub on casing.
NOTE Impeller clearances will vary. Refer to vendor technical manual for impeller clearance gap. d. LOOSEN each bearing housing bolt until desire impeller clearance gap can be obtained between the bearing housing and the underside of the bearing housing bolts.
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e. Evenly TIGHTEN impeller adjustment bolts until bearing housing is tight against the bearing housing bolts f. TIGHTEN the locknuts on the impeller adjustment bolts (Wrench tight) g. VERIFY the impeller can be rotated by hand with no indication of rubbing on the casing. L. Adjusting impeller clearance using Dial Indicator Method
Figure J.2 Impeller Adjustment – Dial Indicator Method
a. LOOSEN locknuts on impeller adjustment bolts. b. LOOSEN impeller adjustment bolts several turns. c. Evenly TIGHTEN bearing housing bolts, while slowly rotating pump shaft by hand until impeller just starts to rub on casing. NOTE Impeller clearances will vary. Refer to vendor technical manual for impeller clearance gap. d. e. f. g.
INSTALL a dial indicator so its tip is positioned on the end of the shaft VERIFY the dial indicator is set to ZERO. LOOSEN each bearing housing bolt 5 – 6 flats. Evenly TIGHTEN impeller adjustment bolts until the dial indicator reads the desired impeller clearance gap. h. TIGHTEN the bearing housing bolts. (Finger tight)
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i. Evenly TIGHTEN the bearing housing and the impeller adjusting bolts while maintaining the desired impeller clearance gap on the dial indicator. (Wrench tight) j. TIGHTEN the locknuts on the impeller adjustment bolts (Wrench tight) k. VERIFY the impeller can be rotated by hand with no indication of rubbing on the casing. 4.7 Final Pump Assembly NOTE Pump may or may not have a constant level oiler.
Figure J..3 Oil Bubbler
A. IF pump has a constant level, THEN FILL bearing housing with proper oil (E.g. MO-2) as follows: a. REMOVE oil bubbler b. ENSURE top tangs in oiler base are level with oil level line marked on side of pump. c. REMOVE filler/vent from top of bearing housing. d. FILL bearing housing with proper oil through the filler/vent UNTIL oil reaches top of tangs inside the oiler base. e. FILL bubbler with proper oil. f. INSTALL bubbler on oiler base. g. ALLOW bubbler to drain UNTIL bubbling stops. h. REPEAT steps (f) and (g) UNTIL bubbler remains approximately ¾ full.
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i. ENSURE vent cap vent holes are clear j. INSTALL vent cap. (Wrench tight) k. WIPE UP any excess oil. B. IF pump DOES NOT have a constant level oiler, THEN: a. REMOVE oil fill plug b. FILL bearing housing with appropriate oil UNTIL level reaches the middle of the sight glass. c. INSTALL oil fill plug. (Wrench Tight) C. IF gland seal supply and leakoff piping were removed, THEN ENSURE piping is clean and INSTALL piping (Wrench Tight) NOTE Use site specific method for performing pump alignment D. ALIGN pump to desired tolerances. E. TIGHTEN hold down bolts while assuring alignment tolerances are maintained F. IF pump has a packing gland THEN: a. INSTALL packing and lantern ring b. INSTALL split GLAND with gland nuts. (Finger Tight) NOTE Use site specific method for installation of packing
NOTE Use site specific method (E.g. lubricant, torque requirements, etc) for installation of coupling depending on coupling type. G. ASSEMBLE coupling using information obtained during disassembly. H. INSTALL coupling guard (Wrench Tight)
5.0 Determine PMT and PMT considerations A. B. C. D. E.
RELEASE clearance/tag out PERFORM vibration testing IF pump has packing, THEN ADJUST packing to achieve proper leakoff. MONITOR inboard and outboard bearing temperatures using a pyrometer. VERIFY no system or oil leaks.
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F. IF insulation was removed, THEN INSTALL insulation. G. IF piping, equipment supports or other interferences were removed, THEN REINSTALL these interferences. H. Work site cleanup - CLEAN work area to original pre-maintenance conditions I. DISPOSE of any generated waste products properly. J. RETURN unused parts to storeroom 6.0 Feedback Mechanisms Identify mechanism to provide work order feedback for improvements and errors A. Perform post job review B. Initiate any corrective action program documents necessary to resolve any problem areas identified. 7.0 References A. B. C. D. E. F. G.
Industrial Safety Manual Foreign Material Control Procedure Material Safety Data Sheets Chemical Traffic Control Procedure Storage of temporary combustibles (transient fire loads) Vendor Technical Manual (Pump) Vendor Technical Manual (Coupling)
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Figure J.4 Typical Model 3196 STX Pump
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K WORK PACKAGE TEMPLATE – STEAM TRAPS NOTE Personnel involved in steam trap testing should be familiar with the fundamental operation of the types of traps to be inspected. This can help avoid misdiagnosis and allow proper interpretation of test results. It is essential for inspection personnel to know how each steam trap operates under specific conditions in order to diagnose the problem correctly. Some test methods require the use of special equipment that will require special training.
1.0 Task Overview 1.1 Component type This work instruction is applicable to various types of steam traps; thermostatic, thermodynamic, mechanical, orifice. 1.2 Equipment tag or unique equipment identifier Ensure unique equipment identifiers are used to designate which steam traps are being inspected. Typically numerous steam traps are tested during a given testing. If traps require maintenance they should be identified on the data sheets for repair. 1.3 Scope This work instruction describes the testing and repair of steam traps. 1.4 Develop list of know consumable materials to be used A. B. C. D. E.
Squeeze water bottle Spanners (required for removing regulator devices from traps) Clean rags Thread lubricant Lapping compound (e.g. Carborundum compound I.F.)
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1.5 Develop a list of know parts to be replaced A. B. C. D.
Cover gaskets Strainers Seats Disks
1.6 Special tools A. Testing a. Mechanics tool pouch b. Industrial stethoscope or ultrasonic test equipment c. Temperature measurement (Contact thermometer, pyrometer, infrared detection equipment. Heat sensitive strips or crayons, etc) B. Maintenance a. Mechanics toolbox 2.0 Pre-job Brief 2.1 Evaluate potential for generation or equipment risk hazards A. Typically testing/inspection of steam traps is performed with the unit on line. In most cases there is little to no risk to the unit or systems during these activities. However, care should be taken since sections of piping may be isolated to perform testing. When isolating any section of piping, consideration should be given as to whether isolating valves will put any other part of the system or personnel at risk. Dangers might include: isolation of vents and protective devices or alarms. Ensure isolation valves are turned closed in a gradual way to avoid system shocks. 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation A. If steam trap requires replacement and is removed from the system, open pipe ends should be covered to preclude foreign material entering system 2.3 Job Safety Analysis, Identifies general and specific hazards A. Steam lines and traps are HOT. Wearing of appropriate personnel safety equipment and work precautions should be observed. B. Manipulation of any valves or equipment should be performed by Operations personnel. C. Prior to opening a trap for inspection or repair the steam supply and return lines to condensate should be isolated. D. When blowing down a steam trap gloves and face shield should be worn. K-2
E. Prior to performing maintenance on steam trap allow the trap to cool to minimize the potential for burns. F. During trap reassemble ensure all joint faces are clean. 2.4 Identify permits required A. Equipment Clearance/Tag out Orders 2.5 Identify Environmental Consideration A. During testing live steam may be released to the environment. Personnel should take necessary precautions and wear appropriate personal safety equipment. B. Steam trap testing is performed with the steam system operating. The plant is typically a high noise area. Appropriate ear protection should be worn. 2.6 Identify Operating Experience Review any relevant plant specific or industry related operating experience applicable to the work being performed. 2.7 Identify Clearance/Tag out Boundary A. Inlet isolation to trap B. Outlet isolation to condensate recovery C. Blowdown valve (If applicable, to depressurize trap) 3.0 Contingency Considerations 3.1 Identify potential scope expansion and actions due to scope expansion A. Inspections of any components may result in the need to repair or replace components as appropriate. B. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work. 3.2 Identify individuals to contact in case certain events occur A. Contact planner if scope growth is identified during work instruction performance B. Contact supervision for any uncertainties with respect to the repair or replacement of worn or damaged parts identified during work instruction performance.
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C. Contact vendor for any clarification of vendor information or additional vendor assistance is required 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions 3.4 Develop material list for potential contingency and consumable parts A. B. C. D. E. F.
Complete replacement steam trap (appropriate design) Regulating devices (bellows, bimetallic, etc) Float ball Bucket Cap/Cover bolts, nuts or clamps Orifice
4.0 Detailed Work Instructions Develop work instructions, utilize existing procedures when applicable Provide expected actions in proper sequence for task. Identify Notes and Cautions where needed A. NOTIFY Operations prior to beginning work (Operator required if valve manipulations will be performed during stream trap testing) B. ENSURE an appropriate clearance/tag out is in place to repair/replace steam trap (If required) C. ENSURE all parts expected to be used are available and in hand D. ENSURE all tools necessary to perform the job are available E. ENSURE appropriate personal safety equipment is worn on the job 4.1 Testing Steam Traps A. Prerequisites a. ENSURE trap is in operation and at normal operating temperature b. TEST for hot trap by squirting a little water on trap cover/cap. If hot water will vaporize immediately. c. IF trap is cold, THEN IDENTIFY trap for maintenance. d. BLOWDOWN strainer (If installed) NOTE If there are traps in close proximity to the trap being tested those traps should be isolated to assist in eliminating any false signals that may be generated by those traps.
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B. CHECK external condition of trap a. Supports b. Insulation c. Corrosion d. Leaks NOTE It is recommended that at least two methods be used to determine whether the steam trap is operating properly. C. PERFORM sound check on traps (Stethoscope or Ultrasonic) a. b. c. d. e.
LISTEN for trap operation (Is it cycling?) LISTEN for mechanical sounds CHECK for continuous high pitch steam flow CHECK for continuous low pitch condensate flow CHECK for intermittent flow NOTE
For closed condensate recovery systems there must be a line with discharge valve available to observe trap discharge. NOTE Operations personnel should perform all valve manipulations. NOTE If the trap has a strainer up stream of the trap, the strainer blowdown valve can be opened to divert condensate away from the trap. This will allow only steam to enter the trap. If the trap is operating correctly it will close and no steam will be observed at the discharge. D. PERFORM visual inspections on traps that sound abnormal. a. CLOSE return line to condensate recovery b. OPEN discharge valve c. OBSERVE discharge for flash steam and normal condensate flow d. OBSERVE discharge for continuous or intermittent flow (trap design dependent. e. OBSERVE trap for discharge of live steam. f. IF any abnormal trap observation is observed, THEN IDENTIFY trap for further testing or maintenance.
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NOTE Condensate return line pressure must be known to assist in determining if trap is operating properly. E. PERFORM temperature check of trap if necessary a. IF temperature is measured by contact thermometer or heat sensitive strips, THEN ENSURE location of temperature measurement is clean, upstream and downstream of trap. b. RECORD steam supply line pressure. c. RECORD condensate return line pressure d. MEASURE supply line temperature e. MEASURE return line temperature f. COMPARE return line temperature to expected return line temperature based on table K.1 – Pipe Line Temperatures at Various Operating Pressures Table K.1 Pipe Line Temperatures at Various Operating Temperatures
Return Line Steam Pressure (psig) 0 (Atmospheric) 15 30 100 150 200 450 600
Return Line Temperature Range (F) 212 225-238 245-260 305-320 330-350 350-370 415-435 435-465
F. IF trap is not operating properly, THEN IDENTIFY trap for repair or replacement. 4.2 Steam Trap Maintenance NOTE Steam trap maintenance can involve either repair or replacement. Repair would be the preferred option especially when the trap is welded into the system. The body’s of most steam traps should last the life of the plant. NOTE Some steam traps are sealed units and can only be replaced
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NOTE Use of a thread lubricant is recommend when installing trap covers/caps or strainer plugs/caps.
4.2.1 Thermodynamic Steam Trap a. ENSURE an equipment clearance/tag out is in place and the steam trap is depressurized and cool to the touch. b. REMOVE cover (Maybe bolted, screw cap or clamped, etc) c. REMOVE old disc d. Fitting new disc 1. ENSURE sealing surface is not overly worn or cut. 2. IF sealing surface is overly worn or has minor cuts THEN LAP seating surface using an approved lapping compound. 3. INSTALL new disc. a. INSTALL cover with using new gasket. b. TORQUE cover to vendor specification c. IF steam trap has and integral strainer, THEN 1. REMOVE strainer plug/cap 2. CLEAN or REPLACE strainer 3. INSTALL plug/cap using new gasket 4. TORQUE plug/cap per vendor specifications d. IF strainer is not integral to steam trap (e.g. located upstream of trap) THEN 1. ENSURE strainer is inside equipment clearance/tag out boundary. 2. REMOVE strainer plug/cap 3. CLEAN or REPLACE strainer 4. INSTALL plug/cap using new gasket. 5. TORQUE plug/cap per vendor specifications 4.2.2 Ball Float Steam Trap NOTE Steam trap operating mechanism typically includes the main valve assembly, pivot frame and ball float. Some float traps also contain a bimetallic device that operates to remove air or non-condensable gases.
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A. ENSURE an equipment clearance/tag out is in place and the steam trap is depressurized and cool to the touch. B. REMOVE cover C. IF strainer is integral to trap THEN CLEAN or REPLACE strainer. D. REMOVE main valve assembly
NOTE All sealing materials should be replaced. If the seats are of the screw in type, they should also be replaced E. F. G. H. I. J.
REMOVE operating mechanism INSTALL new seat (if applicable) IF trap was blowing through due to float failure THEN REPLACE float. INSTALL operating mechanism INSTALL cover using a new gasket. IF trap has a bimetallic air vent assembly, THEN a. REMOVE air vent assembly b. REFURBISH air vent assembly with new parts (gasket. O-ring, seat, etc.) c. INSTALL air vent assembly K. IF strainer was not integral to trap THEN: a. ENSURE strainer is inside equipment clearance/tag out boundary. b. REMOVE strainer plug/cap c. CLEAN or REPLACE strainer d. INSTALL plug/cap using new gasket. e. TORQUE plug/cap per vendor specifications 4.2.3 Balance Pressure Steam Trap A. ENSURE an equipment clearance/tag out is in place and the steam trap is depressurized and cool to the touch. B. REMOVE cover (Maybe bolted, screw cap or clamped, etc) C. REMOVE capsule and spacer plate NOTE Seats are typically screw type but will vary by vendor. D. E. F. G. H. I.
REMOVE valve seat REMOVE strainer screen and CLEAN or REPLACE strainer screen INSTALL new valve seat INSTALL new capsule and spacer INSTALL cover TORQUE cover to vendor specifications.
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4.2.4 Thermostatic Steam Trap A. ENSURE an equipment clearance/tag out is in place and the steam trap is depressurized and cool to the touch. B. REMOVE cover/cap (Maybe bolted, screw cap or clamped, etc) C. REMOVE disc or bellows assembly. D. INSPECT seating surface E. IF seating surface is only slightly worn or has minor steam cuts THEN LAP seating surface using an approved lapping compound. F. INSTALL new disc G. INSTALL cover/cap H. TORQUE cover/cap to vendor specifications. I. IF steam trap has and integral strainer, THEN a. REMOVE strainer plug/cap b. CLEAN or REPLACE strainer c. INSTALL plug/cap using new gasket d. TORQUE plug/cap per vendor specifications J. IF strainer is not integral to steam trap (e.g. located upstream of trap) THEN a. ENSURE strainer is inside equipment clearance/tag out boundary. b. REMOVE strainer plug/cap c. CLEAN or REPLACE strainer d. INSTALL plug/cap using new gasket. e. TORQUE plug/cap per vendor specifications
4.2.5 Inverted Bucket Steam Trap A. ENSURE an equipment clearance/tag out is in place and the steam trap is depressurized and cool to the touch. B. DISCONNECT outlet chamber C. REMOVE cover, valve seat assembly and bucket D. REMOVE bucket from valve lever E. REMOVE valve seat F. INSTALL new valve seat G. REMOVE check valve (if installed) H. INSTALL new check valve (if installed) I. INSTALL new lever J. INSTALL bucket on valve lever K. INSTALL valve seat assembly L. INSTALL cover using new gasket M. CHECK strainer by: a. ENSURE strainer is inside equipment clearance/tag out boundary. b. REMOVE strainer plug/cap c. CLEAN or REPLACE strainer d. INSTALL plug/cap using new gasket. e. TORQUE plug/cap per vendor specifications
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NOTE Liquid expansion steam traps are calibrate at the factory for a set temperature, but can be adjusted. Amount of adjustment will vary by vendor. Typically the trap may be adjusted approximately 50 degrees F. 4.2.6 Liquid Expansion Steam Trap NOTE Steam trap should be in service during trap temperature adjustment to observe response.
A. Adjusting trap operating point a. LOOSEN adjustment locknut b. REFER to vendor technical manual for which direction (CW or CCW) to turn the adjustment nut to raise or lower temperature at which the trap opens. c. ADJUST trap to desired setting d. TIGHTEN adjustment locknut B. Changing the temperature element a. REMOVE trap (typically screw inlet and outlet) b. REMOVE adjustment locknut c. REMOVE overload spring d. REMOVE adjustment nut e. REMOVE element f. REMOVE valve seat g. INSTALL new valve seat h. INSTALL new element i. INSTALL new overload spring j. INSTALL adjusting nut and locknut k. INSTALL trap l. ADJUST trap’s operating temperature using 4.2.6.A. 5.0 Determine PMT and PMT considerations NOTE Steam traps should be returned to service slowing allowing time for them to warmup. A. Return steam trap to service B. Check steam traps for leaks. C. Retest steam trap for proper operation
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6.0 Feedback Mechanisms Identify mechanism to provide work order feedback for improvements and errors A. Perform post job review B. Initiate any corrective action program documents necessary to resolve any problem areas identified. 7.0 References A. Industrial Safety Manual B. Applicable vendor technical manuals C. Foreign Material Control Procedure
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L WORK PACKAGE TEMPLATE – GATE AND GLOBE VALVES 1.0 Task Overview 1.1 Component type This work instruction is applicable to general globe and gate valves. 1.2 Equipment tag or unique equipment identifier Ensure unique equipment identifier is used to designate which valve is being worked. 1.3 Scope This work instruction provides generic instruction for the inspection and minor repair of globe or gate valves. 1.4 Develop list of know consumable materials to be used A. B. C. D. E. F.
Lapping compound (various grades) Container (bags) for temporary storage of studs and nuts Emery cloth/crocus cloth Isopropyl alcohol or acetone Prussian Blue Thread lubricant
1.5 Develop a list of know parts to be replaced A. B. C. D.
Gaskets O-rings Packing Lantern rings (if used)
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1.6 Special tools A. B. C. D.
Lapping blocks (various sizes depending on valve size) Torque wrenches Mechanics tool box Rigging equipment
2.0 Pre-job Brief 2.1 Evaluate potential for generation or equipment risk hazards 2.2 Identify Foreign Material Exclusion (FME) potential and mitigation A. Foreign material exclusion and practices should be implemented prior to opening a check valve for maintenance. 2.3 Job Safety Analysis, Identifies general and specific hazards A. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work. B. Valve to be worked should be isolated, depressurized, cooled and vented prior to work. C. Maintain work area clean to prevent foreign material from entering open system and to minimize the potential for unnecessary safety hazards. D. If valve body is left unattended a cover should be placed over the opening to preclude foreign material from entering. E. Handle cleaning chemicals (alcohol, acetone. etc) in accordance with approved plant procedures and MSDS. F. Some gaskets may contain asbestos. If gaskets may contain asbestos appropriate asbestos abatement procedures should be followed. G. Care should be taken when handling valves and valve parts. Improper handling or undue forces applied during disassemble and assembly could damage valves and affect performance. 2.4 Identify permits required A. Equipment Clearance/Tag out Orders B. Chemical Control Procedures (handing and disposal) C. Asbestos abatement procedures (if applicable)
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2.5 Identify Environmental Consideration A. Refer to Material Safety Data Sheets (MSDS) for proper handling and disposal of special chemicals (E.g. cleaning solvents) B. Handling and disposal of chemicals (E..g. solvents, oil, grease, etc) should be in accordance with approved chemical control procedures 2.6 Identify Operating Experience Review any relevant plant specific or industry related operating experience applicable to the work being performed and the use of the tube cleaning equipment. 2.7 Identify Clearance/Tag out Boundary A. Inlet isolation valve B. Outlet isolation valve C. If there is any power operated equipment inside the isolation boundary, then power should be removed from that equipment. 3.0 Contingency Considerations 3.1 Identify potential scope expansion and actions due to scope expansion A. Inspections of any components may result in the need to repair or replace components as appropriate. B. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work. 3.2 Identify individuals to contact in case certain events occur A. Contact planner if scope growth is identified during work instruction performance B. Contact supervision for any uncertainties with respect to the repair or replacement of worn or damaged parts identified during work instruction performance. C. Contact engineering if flow tests or vibration monitoring can not meet acceptable limits within the scope of work D. Contact vendor for any clarification of vendor information or additional vendor assistance is required
L-3
3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions 3.4 Develop material list for potential contingency and consumable parts A. B. C. D. E.
Seats Disks Bolting material (Nuts, studs, etc) Stem Pressure seal ring (if applicable)
4.0 Detailed Work Instructions Develop work instructions, utilize existing procedures when applicable Provide expected actions in proper sequence for task. Identify Notes and Cautions where needed A. B. C. D. E. F.
NOTIFY Operations prior to beginning work ENSURE an appropriate clearance/tag out is in place to perform work safely ENSURE all parts expected to be used are available and in hand ENSURE all tools necessary to perform the job are available ENSURE appropriate personal safety equipment is worn on the job DETERMINE rigging requirements, bolts, nuts, stud sizes, laydown areas, etc) NOTE
The following is a suggested sequence of work. Steps should be modified as required or worked out of sequence depending on the particular valve being worked. 4.1 Disassembly NOTE Some steps may not be applicable depending on the check valve being worked. Those steps should be NA’d.
A. IF valve has an operator installed, THEN REMOVE operator (AOV, MOV, reach rod, chain operator, etc) B. REMOVE other interferences as required to support maintenance. (air supply tubing, limit switches, hangers, supports, snubbers, etc)
L-4
NOTE Bonnet bolts, nuts and other small parts removed during disassembly should be bagged, tagged and stored appropriately for reassembly.
NOTE If a pressure seal ring is installed, its removal should be as per vendor recommendations.
CAUTION Valve should be off the closed seat to ensure any trapped pressure is relieved prior to removing the bonnet. C. DISASSEMBLE valve bonnet bolted connections, pressure seal ring bolts OR valve flange connections from system. D. MATCH MARK valve bonnet flanges for proper reassembly. CAUTION If rigging is used to remove bonnet, stem and disc rigging should be position such that the lifting force is along the axis of the stem to avoid damage to disc and seat.
CAUTION If the valve being worked is a gate valve and the gate valve discs do not have flow direction marks, mark the discs with a marker for proper assembly. E. INSTALL rigging to remove bonnet, stem and disc. F. REMOVE valve bonnet, stem and disc. G. COVER exposed piping or open valve to prevent foreign material from entering the system. 4.2 Inspections NOTE Not all valves will contain all parts listed.
A. INSPECT and RECORD degradation, damage, excessive wear, corrosion, erosion, biofouling, etc for the following valve parts.
L-5
a. Body b. Seat surfaces c. Disc d. Body to bonnet gasket surface e. Packing surfaces f. Pins, guides, etc. g. Bolting materials (bolts, nuts, studs, etc) h. O-rings/gaskets B. IF valve is a globe valve, THEN INSPECT disc anti-rotational device and NOTE any signs of rotation. C. CHECK seating surfaces using the bluing method. D. REPAIR or REPLACE all damaged or degraded parts. 4.3 Valve repairs NOTE Lapping should be performed per approved plant procedures and training.
CAUTION Valve seating angles should not be changed during the lapping process. A. B. C. D.
IF seat and disc surfaces are not badly damaged, THEN LAP seats and disc. CHECK seat and disc surfaces for proper fit by bluing method. REPEAT lapping until acceptable bluing is obtained. CLEAN valve internals. CAUTION
Locking devices or staking of threads is used in some applications to ensure parts do not vibrate loose. (E.g. bolting on split clamps to attach valve yokes to bodies, setscrews to pin globe valve stems in place, etc) E. CHECK appropriate locking devices for tightness.
L-6
4.4 Reassembly CAUTION Gasket seating surfaces and pressure seal ring (if installed) should be clean to minimize the potential for leaks after reassembly.
A. B. C. D.
ENSURE gasket seating and pressure seal ring surfaces clean. ENSURE pipe and valve flange/threads are clean. CLEAN all internal parts with isopropyl alcohol/acetone. INSPECT internals of valve for any foreign material. NOTE
Match marks should be observed when installing bonnet. NOTE If pressure seal ring is installed it should be installed per vendor recommendations. E. INSTALL valve bonnet, stem and disk. F. INSTALL and TORQUE bonnet bolts, pressure seal ring or flanges as appropriate per vendor recommendations. G. ENSURE local position indication is correct for valve position. H. PACK valve stem per approved plant procedures and vendor recommendations. I. INSTALL valve operator. J. INSTALL all interferences that were removed during disassembly. 5.0 Determine PMT and PMT considerations A. B. C. D.
Stroke valve and ensure valve operates smoothly. Check for any leaks. (packing, body to bonnet, flanged connections, etc). Check local indication and ensure it agrees with actual valve position. If limit switches are installed for remote indication verify proper operation.
6.0 Feedback Mechanisms Identify mechanism to provide work order feedback for improvements and errors A. Perform post job review B. Initiate any corrective action program documents necessary to resolve any problem areas identified.
L-7
7.0 References A. B. C. D. E. F. G. H.
Industrial Safety Manual Applicable vendor technical manuals Applicable valve and actuator drawings Valve Packing Procedure Lapping Procedure Foreign Material Control Procedure Material Safety Data Sheets Chemical Traffic Control Procedure
L-8
M WORK PACKAGE TEMPLATE – MULTI-STAGE VERTICAL PUMP NOTE Personnel performing this work instruction should be qualified (properly trained and proficient) on the type of pump being worked. 1.0 Task Overview 1.1 Component type This work instruction is applicable to a typical multistage vertical pump. (E.g. intake cooling water, raw cooling water, and screen wash pumps, etc) 1.2 Equipment tag or unique equipment identifier Ensure the unique pump identifier is used to designate which pump is being worked. 1.3 Scope
This work instruction provides instructions for inspection and repair of a multi-stage vertical pump. 1.4 Develop list of know consumable materials to be used A. B. C. D. E. F. G.
Coating material (E.g. Amerlock 400, etc) Grease for O-rings (E.g. Dow Corning, etc) Grease for bearings (E.g. GP-1) Never-seize or equivalent Neolube or equivalent Silicon spray Solvent (E.g. alcohol, acetone, etc)
M-1
1.5 Develop a list of know parts to be replaced
A. B. C. D. E. F. G. H.
Various O-rings and gaskets (Bowl, column, etc) Assorted fasteners (nuts, cap screws, studs, washers) Split rings Impeller keys Packing Bottom Bearing Column bearings (ensure proper thickness, Go/No-Go gauge) Wear rings
1.6 Special tools A. B. C. D. E. F. G. H. I. J. K. L.
Mechanics tool box (wrenches, screwdrivers etc) Puller for bearings and wear rings Go/No-Go gauge for rubber column bearings FME covers for open pump well and discharge flange Cribbing for pump support Timbers for shaft storage V-blocks for shaft runout measurement Pump column saddle support Installed hoist or crane Lifting fixtures (discharge head, columns, etc) Rigging Measurement and Test Equipment (M&TE) a. Inside and outside Mic’s (various sizes as required by pump geometry) b. Dial indicator c. Feeler gauges d. Torque wrenches (various sizes based on vendor requirements)
2.0 Pre-job Brief 2.1 Evaluate potential for generation or equipment risk hazards A. Generation B. Equipment Risk/Damage
M-2
2.2 Identify Foreign Material Exclusion (FME) potential and mitigation A. Performance of this work will open pump to environment. Appropriate measures should be taken to prevent foreign material from entering the pump. 2.3 Job Safety Analysis, Identifies general and specific hazards A. DO NOT allow petroleum based products to contact the EPT O-rings of the mechanical seal. Petroleum based products will cause the O-rings to deteriorate and fail. B. Oil drained from the pump should be removed from the work area and properly disposed of as soon as practical. Other wise, an appropriate transient fire load evaluation should be performed and proper temporary storage provided. C. Follow appropriate Material Safety Data Sheet (MSDS) and site approved procedures for handling and disposal of cleaning chemicals and solvents. D. Follow approved site procedures for proper draining and disposal of process fluids from the pump. 2.4 Identify permits required A. Equipment Clearance Order B. Chemical Control Permit C. Transient combustible material storage permit 2.5 Identify Environmental Consideration A. Refer to Material Safety Data Sheets (MSDS) for proper handling and disposal of special chemicals (E.g. cleaning solvents) B. Handling and disposal of chemicals (E..g. solvents, oil, grease, etc) should be in accordance with approved chemical control procedures. 2.6 Identify Operating Experience Review any relevant plant specific or industry related operating experience applicable to the work being performed.
M-3
2.7 Identify Clearance/Tag out Boundary A. B. C. D. E. F. G. H.
Pump discharge valve Pump Vent valve Pump Drain valve Power to motor Power to motor space heaters Power to heat tracing (if applicable) Supply and discharge to motor cooling water (if applicable) Lube water supply
3.0 Contingency Considerations 3.1 Identify potential scope expansion and actions due to scope expansion A. Inspections of any components may result in the need to repair or replace components as appropriate. B. Additional work identified during the performance of this work instruction requires a scope change to plan newly identified work. 3.2 Identify individuals to contact in case certain events occur A. Contact planner if scope growth is identified during work instruction performance B. Contact supervision for any uncertainties with respect to the repair or replacement of worn or damaged parts identified during work instruction performance. C. Contact vendor for any clarification of vendor information or additional vendor assistance is required 3.3 Identify rapid or emergency actions to place equipment in likely compensatory configurations or conditions 3.4 Develop material list for potential contingency and consumable parts A. B. C. D. E. F. G. H. I.
Impellers Impeller liners Couplings Pump half, motor half, shaft) Suction Bell (Pre-coated) Pump bowls (Pre-coated) Columns (Pre-coated) Pump Shaft Complete bowl assembly Discharge head M-4
J. Coating material (E.g. Amerlock 400, Belzona, etc) 4.0 Detailed Work Instructions Develop work instructions, utilize existing procedures when applicable Provide expected actions in proper sequence for task. Identify Notes and Cautions where needed A. B. C. D. E. F.
NOTIFY Operations prior to beginning work ENSURE an appropriate clearance/tag out is in place to perform work safely ENSURE all parts expected to be used are available and in hand ENSURE all tools necessary to perform the job are available REVIEW and UNDERSTAND the scope of work before the start of any field activities. ENSURE appropriate personal safety equipment is worn on the job
4.1 Preparations A. VERIFY clearance/tag out is correctly in place B. LOCATE and IDENTIFY proper piece of equipment is being worked per the work instruction C. ENSURE piping, equipment supports, and other interferences are removed to support work. D. ENSURE all rigging to be used is inspected and in good condition prior to use. E. IF installed, THEN REMOVE insulation. CAUTION Appropriate rigging techniques should be observed during motor removal. 4.2 Motor Removal A. DISCONNECT motor cooling lines (if applicable) B. INSPECT motor cooling lines for any biofouling, silt, corrosion, etc. C. PROVIDE FME protection for open lines. NOTE Ensure as-found coupling gap is measured and recorded. D. DISCONNECT coupling. E. REMOVE motor. NOTE Depending on pump not all parts will be applicable.
M-5
CAUTION Some packing material contains lead. Refer to appropriate MSDS for proper handing and disposal 4.3 Disassembly and removal of discharge head A. B. C. D. E. F. G. H.
REMOVE adjusting plate, pump half coupling and key REMOVE gland and packing REMOVE shaft sleeves and O-Rings REMOVE stuffing box and O-Rings REMOVE bearing REMOVE discharge head to sole plate nuts MATCH MARK column to discharge head. LIFT pump and INSTALL saddle support between the outer column upper flange and sole plate I. REMOVE discharge head. J. INSTALL FME cover for pump well 4.4 Disassembly of columns and line shafts NOTE All columns should be match marked before they are disassembled. NOTE The number of columns and line shafts will vary from one installation to another NOTE Shaft should be clean and lubricated prior to sliding coupling along shaft. A. LIFT pump assembly to relieve pressure off saddle support. B. REMOVE saddle support. C. LIFT pump assembly until upper flange of next column is high enough to install saddle support. D. INSTALL saddle support and lower pump assembly on to support. E. REMOVE outer column and bearing retainer F. DISCONNECT line shaft coupling. G. SECURE shaft coupling to prevent sliding down the shaft. H. REMOVE line shaft and coupling. I. REPEAT steps 4.3.A through 4.3.H until all columns and line shafts are removed. CAUTION Cover should be installed over pump well when open to prevent foreign material form entering and prevent personnel injury.
M-6
4.5 Disassembly or Bottom column section A. REMOVE the last column section and pump from well. B. INSTALL cover over open pump well. NOTE Shaft should be clean and lubricated prior to sliding coupling along shaft. NOTE Pump assembly should be supported by cribbing. C. D. E. F. G. H.
MOVE pump to predetermined and prepared work area MATCH MARK bottom column section to pump assembly REMOVE bottom column and bearing retainer. DISCONNECT coupling SECURE coupling to prevent sliding down shaft REMOVE line shaft and coupling
4.6 Impeller Bowl disassembly NOTE The number of impeller bowls differ form one installation to another. Impeller bowl designs differ from vendor to vendor. NOTE Pump bowls and other parts should be match marked as necessary prior to disassembly to aid in assuring proper reassembly. NOTE Shaft should be clean and lubricated prior to sliding impeller along shaft. A. Upper bowl disassembly a. REMOVE upper bowl from pump assembly. b. SLIDE impeller from shaft and remove impeller key. c. REMOVE next bowl from pump assembly. d. REMOVE thrust collar and associated parts. e. SLIDE next stage impeller from shaft and remove impeller key. B. Remaining bowls disassembly a. REMOVE bowl from pump assembly. b. SLIDE impeller from shaft and remove impeller key
M-7
c. REPEAT steps a and b above until last bowl is removed from suction bell and first stage impeller is removed. 4.7 Inspection of Pump components NOTE All pump components should be inspected for general conditions such as excessive wear, corrosion, cracks, pitting, coating condition, etc.
NOTE Components may be machined, polished or reconditioned as necessary as long as component tolerances are maintained. NOTE All damaged, out of tolerance or excessively worn components should be replaced. All elastomers should be replaced. NOTE Because line shafts are typically symmetrical, if they meet runout tolerances but show excessive wear in the bearing area, they can be inverted. A. MEASURE the following shafts for runout and excessive wear in bearing regions. NOTE Runout tolerances are per facility or vendor recommendation. a. Pump shaft b. Line shafts c. Column shafts
B. MEASURE the following bearings in two directions to ensure eccentricity. a. Top shaft bearing b. Bowl bearing c. Bottom bearing NOTE Bearing material varies by vendor. (e.g. bronze, rubber, etc.) C. Inspection of column bearings a. MEASURE inside diameter of bearings (tolerance as per vendor recommendation)
M-8
b. REPLACE bearings that do not meet acceptance criteria. NOTE All components not meeting vendor tolerances should be replaced. D. Inspection of impellers, wear rings and impeller liners a. INSPECT impellers for cavitation damage and damage from impeller dragging against impeller liner. b. INSPECT impeller liners for damage caused by impeller dragging against liner. c. MEASURE clearance between bowl wear rings and impeller wear area. E. INSPECT stuffing box threaded pipe connections (lube water) for corrosion, erosion, etc. F. Inspection of pump bowls and suction bell a. INPSECT coatings (inside and outside) on all bowls and suction bell. b. REPAIR any damaged coatings NOTE If the bowls and suction bell are coated and there is no degradation in the coatings, there is no need to measure wall thickness. c. MEASURE wall thickness. d. IF wall thickness does not meet acceptance criteria, THEN REPLACE bowl. G. Inspection of columns a. INSPECT coatings on all columns b. REPAIR any damaged coatings c. INSPECT columns for any cracks. NOTE If the columns are coated and there is no degradation in the coatings, there is no need to measure wall thickness. d. MEASURE column wall thickness is acceptable (per vendor recommendation) e. IF column is cracked or wall thickness is unacceptable, THEN REPAIR or REPLACE column. H. Inspection of discharge head a. b. c. d.
INSPECT discharge head coatings. IF coatings are damaged, THEN REPAIR coatings. INSPECT discharge head for cracks. IF discharge head has cracking, THEN REPAIR or REPLACE discharge head.
M-9
4.8 Pump Assembly NOTE Lubricate all nuts and screws with approved lubricant during assembly. NOTE Lubricate all elastomers with approved lubricant during assembly. NOTE Torque of nuts and screws is to be accomplished as per plant instructions.
4.8.1 Assembly of pump bowls
A. B. C. D. E. F.
ASSEMBLE first stage impeller, thrust collar and associated parts onto the pump shaft. INSTALL O-ring on suction bell. LUBRICATE bottom bearing and affected area of pump shaft. INSTALL pump shaft into suction bell. INSTALL and TORQUE first stage suction bowl onto suction bell. ASSEMBLE remaining suction bowls as follows.
NOTE After the next stage impeller is installed it should be verified that the impellers seat simultaneously. a. ASSEMBLE impeller, thrust collar and associated parts onto the pump shaft. b. VERIFY impellers seat simultaneously. (Use a feeler gauge and tolerance should be as per vendor technical manual recommendation) c. IF impellers do not seat simultaneously, THEN MACHINE either impeller split rings or impeller liner d. INSTALL O-ring onto previously installed bowl. e. INSTALL and TORQUE next stage bowl on to previous stage bowl. f. REPEAT (a – e) above for remaining bowls until pump assembly is complete. CAUTION Excessive grease in the bottom bearing cavity may hydraulically restrict shaft from lowering into the position required for impeller adjustment. G. LUBRICATE suction bell bottom bearing cavity. H. BOTTOM OUT shaft in bottom bearing cavity. I. PACK bottom bearing cavity full of grease.
M-10
NOTE Shafts, couplings, split rings, keys, etc should be clean, lubricated and free of dirt to prevent galling during assembly. 4.8.2 Assembly of lower line shaft and column to pump assembly
NOTE Keys may be filed or machined to achieve proper fit and prevent binding during assembly. A. ENSURE coupling and key is installed and secured on shaft to prevent sliding during assembly. B. ENSURE pump assembly is vertical and firmly supported on cribbing. C. INSTALL and TORQUE lower line shaft to pump assembly. D. INSTALL O-ring onto top bowl. E. INSTALL and TORQUE lower column to pump assembly. F. LUBRICATE and INSTALL bearing into lower column bearing retainer. 4.8.3 Installation of lower pump assembly in pump well
A. B. C. D. E.
MOVE pump and lower column assembly to pump well. REMOVE pump well cover. LOWER pump allowing clearance to install saddle support. INSTALL saddle support. LOWER pump onto saddle support.
4.8.4 Installation of line shafts and columns
NOTE Repeat the following steps until all line shafts and columns have been assembled. NOTE Columns, shafts, couplings, split rings, keys, etc should be clean, lubricated and free of dirt to prevent galling during assembly. NOTE Refer to match marks during assembly. A. ENSURE coupling and key is installed and secured on shaft to prevent sliding during assembly. B. POSITION, INSTALL and TORQUE line shaft to preceding line shaft. C. INSTALL O-ring onto column. M-11
D. E. F. G. H. I.
POSITION, INSTALL and TORQUE column to preceding column. LIFT pump column assembly to clear saddle support REMOVE saddle support. LOWER pump assembly and POSITION saddle support. LUBRICATE and INSTALL bearing into column bearing retainer. REPEAT steps [A] through [H] until all line shafts and columns have been assembled and installed.
4.8.5 Installation of discharge head
NOTE All gasket seating surfaces should be clean and free of debris. A. B. C. D. E. F. G.
LUBRICATE and INSTALL O-ring onto top column. INSTALL and TORQUE discharge head to upper column. INSTALL discharge flange gasket. LIFT pump from saddle support. REMOVE saddle support. LOWER discharge head while aligning flange seating surfaces and gasket. TORQUE discharge head to sole plate and discharge head to pipe flange using approved torque methods.
4.8.6 Final Assembly
A. B. C. D. E. F. G. H. I. J. K. L. M.
INSTALL stuffing box, throttle bushing and O-rings. INSTALL shaft sleeve and O-rings. INSTALL pump half coupling and adjusting plate. INSTALL motor. INSTALL any interferences removed during disassembly. (E.g. hangars. Supports, etc) RELEASE clearance/tag out on motor. BUMP motor to ensure proper rotation. REHANG clearance/tag out on motor. ADJUST impeller lift per vendor recommendation. INSTALL pump packing as per vendor recommendation. INSTALL and ENSURE gland is square to stuffing box. INSTALL lube water lines. INSTALL motor cooling water lines (if applicable)
5.0 Determine PMT and PMT considerations A. RELEASE clearance/tag out B. PERFORM vibration testing C. PERFORM flow testing to verify that pump lift is satisfactory. M-12
NOTE Packing and leak-off flow should be monitored closely during initial break-in following maintenance. D. E. F. G. H. I. J. K.
ADJUST packing to achieve proper leak-off flow. MONITOR gland temperature during break-in run. VERIFY no system leaks. IF insulation was removed, THEN INSTALL insulation. IF heat tracing is installed and was removed, THEN INSTALL heat tracing. Work site cleanup - CLEAN work area to original pre-maintenance conditions DISPOSE of any generated waste products properly. RETURN unused parts to storeroom
6.0 Feedback Mechanisms Identify mechanism to provide work order feedback for improvements and errors A. Perform post job review B. Initiate any corrective action program documents necessary to resolve any problem areas identified. 7.0 References A. B. C. D. E. F.
Industrial Safety Manual Foreign Material Control Procedure Material Safety Data Sheets Chemical Traffic Control Procedure Storage of temporary combustibles (transient fire loads) Vendor Technical Manual (Pump)
M-13
Figure M-1 Cross-section of a typical multistage vertical pump.
M-14
N LISTING OF KEY INFORMATION N.1 Key O&M Cost Points Key O&M Cost Point Emphasizes information that will result in overall reduced costs and/or increase in revenue through additional or restored energy production. Referenced Section
2.1
2.1
2.2 2.4
3.3
Page Number
Key Point To best meet the competitive challenge the continually improving maintenance organization is finding ways to work smarter. Working smarter means being ready for the expected and the unexpected. The labor resource is one of the largest and expensive within the maintenance department. If the labor resource is not being utilized effectively and efficiently, a significant amount of money is being wasted. The work package template will provide the maintenance organization with a more accurate and efficient tool for the scheduling and execution of maintenance activities. There will be short term costs associated with the development of the specific work packages but the long term gains will outweigh these costs. The planner should be aware that contingency parts may or may not be necessary to support the job. This can be a significant financial decision since most contingency parts tend to be high cost items that are not maintained in normal inventory.
N-1
N.2 Key Human Performance Points Key Human Performance Point Sometimes it is not necessary to measure the “goodness” of your safety culture, as it is to recognize signs that are indications of a poor or failing safety culture. Some of the key indicators of a poor or failing safety culture are easily observable. Referenced Section
2.1 2.5
3.2
3.6
Page Number
Key Point Work packages provide the maintenance craftsman with the level of detail necessary to perform a work activity correctly, efficiently and safely. The planning walkdown is essential for the development of pre-job considerations and contingencies. The review of operating experience can help reduce risk to both personnel and equipment by learning from past mistakes or problems that have been encounter in the industry or at the given facility. Feedback is a credible source of information that can result in the improvement in the organization of work, support worker performance, improve job productivity and identify opportunities to strengthen human performance and reduce errors.
N-2
N.3 Key Technical Points Key Technical Point Targets information that will lead to improved equipment reliability. Referenced Section
2.1
3.3
Page Number
Key Point The use of developed work package templates allows the maintenance organization to move from the fire-fighting mode of performing work to an operational mode that is structured and proactive. The level of effort placed on contingency planning should be commensurate with the scope and significance of the maintenance activity. The planner should attempt to anticipate necessary contingencies based on previous work experience, operating history and other intelligence.
N-3
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