Specification for Cathodic Protection system equipment and materials.doc
Short Description
The equipment required for cathodic protection of underground LPG mounded bullet tanks are clearly explained....
Description
2 x 1000 MT LPG Storage Mounded Vessels at Haldia For PHDPL LPG Pipeline System,
DOCUMENT TITLE
: SPECIFICATION FOR CATHODIC PROTECTION SYSTEM EQUIPMENT AND MATERIALS
DOC. NO.
: IOCL-SJ204-CP-DOC-5001
REV.
:0
ISSUED FOR
: INFORMATION APPROVAL CONSTRUCTION REVIEW
0
19-10-13
REV REV DATE ALL RIGHTS RESERVED
ISSUED FOR APPROVAL EFF DATE
PURPOSE
PREPARED BY REVIEWED BY APPROVED BY
SPECIFICATION FOR CATHODIC PROTECTION SYSTEM EQUIPMENT AND MATERIALS
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INDEX
1.0INTRODUCTION........................................................................................................................2 2.0ABBREVIATIONS.......................................................................................................................3 3.0CODES AND STANDARDS.......................................................................................................3 4.0POWER SUPPLY REQUIREMENTS.........................................................................................4 5.0SERVICE CONDITIONS............................................................................................................5 6.0GENERAL REQUIREMENTS....................................................................................................5 7.0EQUIPMENT DETAILS..............................................................................................................5 8.0QUALITY ASSURANCE...........................................................................................................19 9.0INSPECTION AND TESTS.......................................................................................................19 10.0MARKING...............................................................................................................................21 11.0PACKING AND DESPATCH..................................................................................................23 12.0REFERENCE DOCUMENTS.................................................................................................23
1.0
INTRODUCTION This specification covers the minimum technical requirements governing the design, manufacture, supply, testing, inspection, preparation for shipment & storage, and delivery to site of Cathodic Protection System Equipment and Materials with all accessories built in compliance with applicable standards, to be installed in 2 X 1000 MT mounded LPG storage vessels as part of the Paradip Haldia Durgapur LPG Pipeline (PHDPL) project.
SPECIFICATION FOR CATHODIC PROTECTION SYSTEM EQUIPMENT AND MATERIALS
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3.0
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ABBREVIATIONS CPTR
Cathodic Protection Transformer Rectifier Unit
MTBF
Mean Time Between Failure
MTTR
Mean Time To Repair
MCB
Miniature Circuit Breaker
HRC
High Rupturing Capacity
MMO
Mixed Metal Oxide
SCR
Silicon Controlled Rectifier
CRCA
Cold Rolled Cold Annealed
MOV
Metal Oxide Varistor
PSP
Pipe to Soil Potential
CVCC
Constant Voltage Constant Current control
AJB
Anode Junction Box
CJB
Cathode Junction Box
TJB
Test Junction Box
MJB
Monitoring Junction Box
FLP
Flame Proof
FAT
Factory Acceptance Test
XLPE
Cross linked Polyethylene
PVC
Polyvinyl Chloride
CODES AND STANDARDS Unless otherwise specified in this specification, all components and equipment shall be based on the following standard: IEC
International Electro technical Commission Standards
IS
Indian Standard
NACE
National Association of Corrosion Engineers
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OISD
Oil Industry Safety Directorate (Elect. Std.)
ASTM
American Society for Testing of Materials
IS-8062
Cathodic Protection of buried pipeline/structure for transportation of natural gas, oil and liquids.
NACE-RP0169
Control of external corrosion on underground or submerged metallic piping systems
ASTM B338
Specification for seamless and welded Titanium and Titanium alloy tubes for condensers and heat exchangers
ASTM B265
Specification for Titanium and Titanium Alloy Strip, Sheet, and Plate
IS: 1554 Part (I)
PVC insulated (heavy duty) electric cables for working voltages upto and including 1100 volts.
IS: 7098 Part (I)
Cross linked polyethylene insulated PVC sheathed cables for working voltages upto and including 1100 volts.
IEC-60227
Polyvinyl chloride insulated cables of rated voltages up to and including 450V/750V
IE60811
Common test methods for insulating and sheathing materials of electric and optical cables
IEC-60885
Electrical test methods for electrical cables
IS: 10418/IEC-60446 Specification for drums for electric cables In the event of conflict between codes and standards being used, the most stringent one shall be followed. Where Indian Standards do not exist or equipment is supplied by foreign manufacturer, relevant international standards shall be applicable.
4.0
POWER SUPPLY REQUIREMENTS ELECTRICITY SUPPLY Supply voltage Frequency
(LV)
:
415V (± 10%)
(LV)
:
240V
:
50Hz ± 3%
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SERVICE CONDITIONS Electrical equipment and material shall be designed and fabricated for use under the following Site conditions.
6.0
Maximum Ambient Temperature
:
43.9 ºC
Minimum Ambient Temperature
:
6.7 ºC
Relative humidity (Maximum)
:
96%
Relative humidity (Minimum)
:
33%
Design Atmospheric Pressure
:
1000 mbara
GENERAL REQUIREMENTS a) All the equipment/material shall be brand new with state of art technology and proven field track record. No prototype equipment shall be accepted. b) The equipment and materials shall be suitable for installation in locations having generally corrosive, warm and humid or dusty atmosphere. c) The equipment shall confirm to the provisions of Indian Electricity rules and other statutory regulations currently in force in the country. d) Equipments for hazardous area shall meet the requirement of IS: 2148 or equivalent international standard and shall be suitable for a gas group IIA & IIB and temperature class-T3 or better. e) The CPTR unit shall be field proven. The design, internal component layout and rating of component shall ensure high MTBF and low MTTR. f)
The anodes shall be suitable for the composition/conditions of soil and should have a design life of 25years (minimum).
7.0
EQUIPMENT DETAILS The Cathodic protection system equipment and associated material shall broadly include 7.1
Transformer Rectifier Unit
7.2
Anodes
7.3
Permanent reference cell
SPECIFICATION FOR CATHODIC PROTECTION SYSTEM EQUIPMENT AND MATERIALS
7.1
7.4
Junction boxes
7.5
Cables
7.6
Calcined petroleum coke breeze
7.7
Corrosion Protection
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Transformer Rectifier unit The transformer rectifier unit shall be complete with the following sections: •
Transformer and input controls
•
Rectifier and filter
•
Output protections
•
System controls
•
Control, indication and metering
•
Alarm and Annunciations
7.1.1
Transformer and input controls:
a) The transformer shall be double wound air cooled type with insulation class F with temperature rise limited to Class B. The separate primary and secondary windings shall have an electrostatic shield, composed of heavy copper foil, in between the two windings. b) The autotransformer shall be similar to main transformer except it will have single winding and tapping for manual mode of control. c) Single phase transformers may be provided upto 50V, 50A DC output rating of the CPTR units. Beyond this rating, 3phase transformers shall be provided. d) The safety factor for the transformer rating shall be minimum 125%. Transformer full load efficiency will not be less than 95%. e) Local winding temperature indicator (WTI) with two potential free contacts for alarm and trip signals shall be provided. f)
CPTR units having multiple output circuits shall have separate secondary windings for each output circuit.
g) Protection from overloads at the input side will be provided by suitable MCBs having thermal overload in addition to separate fuse protection for each diode. h) Input current limiting reactor of suitable rating shall be provided at the input line of the main transformer to avoid nuisance tripping of MCB.
SPECIFICATION FOR CATHODIC PROTECTION SYSTEM EQUIPMENT AND MATERIALS 7.1.2
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Rectifier and filter:
a) The rectifier unit shall be made of SCRs as basic components. b) The CPTR unit shall be suitable for 415V AC, 3-ph power supply. Rectifier shall be 3 phase full wave type and controlled type. For CPTR units rated 50V, 50A DC or less, the unit may be suitable for 240V AC, 1-ph power supply and the rectifier shall be full wave type and controlled type. c) The current and voltage ratings of thyristors, diodes shall be at least two times the actual maximum device current and minimum two times the actual maximum voltage coming across the device respectively. d) The rectifier section shall be provided with Silicon Controlled Rectifiers mounted on heat sinks having adequate capacity to prevent the case temperature more than 100 Deg C at ambient temperature. The peak inverse voltage rating and current ratings of the diodes shall be 1200V. The diodes shall be connected in Bridge circuitry for full wave rectification. Each diode in the bridge circuit shall be protected by semiconductor fuses. e) Each SCR and diodes shall be protected from voltage surges coming from the incoming power supply and from output side from the pipeline. Required shunt zeners /MOV shall be provided across the rectifier elements for protection. f)
Adequate filtering shall be provided on the DC output of the rectifier to limit the ripple content in the output to less than 5% at rated load both in Auto and Manual mode of operation.
g) The TR units shall be designed in such a manner that ripple factor does not exceed 5% of rated load both in Auto and Manual mode of operation. 7.1.3
Output Protections:
a) Protection from overload on the output in auto mode for TR unit will be provided by another close loop SCR control circuitry giving automatic constant current control act as back up control to main auto mode control. Separate PCB shall be used for main auto mode control and the backup control. The current limit for backup control is to be set by two limit switches marked "coarse" and "fine". The limits of the two switches shall be algebraically additive and shall give equal steps of 3A each upto 110% rated current. One scale calibrated in Ampere shall be provided with each limit switches so that current limit can be set by operator at any desired value in 3A step. In any circumstances the TR unit output current should not exceed the current limit set by the backup control even in case of short circuit.
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b) In addition to above electronic current limiting feature HRC fuse of suitable ratings shall be provided at positive and negative terminals in addition to one double pole MCB. 7.1.4
System controls:
The TR unit shall be provided with manual and auto controlled mode of operation through selector switches as per the following a) Manual Mode: In manual mode, the output of TR units shall be controlled from 0 volts to rated value in 23 equal steps through a Auto Transformer with tapping will be provided for voltage control in this mode. Output voltage of 110% rated voltage shall be available by means of coarse and fine tap changing switches for rated input supply voltage and 110% rated output current. The controlled output voltage of auto transformer shall be fed to main transformer input and output of the main transformer shall be rectified for DC output. In auto mode, two types of control shall be provided which are as follows: b) Potential Control: In this mode of operation the output of the CPTR unit shall operate in an external closed loop with pipe to soil potential (PSP), measured by reference cell, in feedback loop. The CPTR unit control shall adjust the output voltage such that the PSP as measured by reference cell always remains equal to the set potential on the unit. The set potential (Vps) shall have high long stability and minimum temperature drift. The unit shall be designed to operate with number of reference cells connected to it. In case of more than one reference cell, CPTR unit shall have feature to automatically select the reference cell having less negative potential than the others and use the same for auto control of the unit. In case of open circuit or short circuit of reference cell or potential being less negative than a minimum set potential (Vrs), the unit shall sense these conditions as reference cell failure and shall automatically switch over to the other healthy reference cell for control. Should fault occur in all the reference cells, the output voltage or current of the CPTR unit shall adjust automatically to a preset value, which shall be adjustable. The unit shall continuously monitor the PSP and necessary annunciation shall be provided in case of PSP either exceeding the specified maximum limit or remaining lower than the specified minimum limit.
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c) Constant Voltage/ Constant Current control mode: In this mode the unit can be operated in either Constant voltage mode OR Constant current mode. The output voltage and current of the unit can be adjusted from 0 to rated value by means of step less voltage and current setter. Constant current feature shall be achieved by automatically adjusting TR unit output voltage between 0 to 110% rated voltage through close loop control using TR unit output current as feedback taken from the shunt inside the TR unit. During current control mode of operation of the TR unit, the following characteristic operating condition should be achieved: •
When there is a variation up to ±10% of input supply voltage, TR unit output current should not vary more than 1.0A from the set current.
•
At any operating current, when load resistance is constant or varies to the extent to allow the unit to operate at current control mode, TR unit output current should not vary more than ±10% operating current.
•
Under any condition, TR output current should not deviate more than ±10% of current limit set by stepped limit switch while continuous output current adjustment potentiometer is set at maximum position.
7.1.5
Control, indication and metering:
Following controls shall be provided on CPTR unit a) ON/OFF control for input through MCB. b) ON/OFF control for output through MCB. c) Auto/CVCC mode selector switch. d) Selector switch for selecting indication of PSP set and PSP actual for all the reference cells. TR unit shall have the following indicating lights a) CPTR unit ‘ON’/ ‘OFF’ b) Unit in auto/CVCC (2 lamps) c) Reference cell controlling the closed loop control of the CPTR unit (number of lamps same as number of reference cells). d) Reference cells faulty e) Pipeline overprotected f)
Pipeline under protected
g) Indications for current interrupter
SPECIFICATION FOR CATHODIC PROTECTION SYSTEM EQUIPMENT AND MATERIALS •
Timer power ‘ON’
•
‘ON’ timing
•
‘OFF’ timing
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Continuous reading, rectangular type (having accuracy within 2% with full load at ambient temperature) meters shall be provided for the following (a) AC voltage (b) AC current (c) DC voltage (d) DC current (e) PSP All meters shall be electronic digital type with LED display (of digit size 12.5mm min.) arrangement and shall be able to indicate the current and voltage ranges up to a resolution of one decimal place for DC Ammeter & Voltmeter and 3 decimal places for PSP meter. All voltmeters shall be provided with separate fuse and toggle switch where as all Ammeters shall be provided with only toggle switch. 7.1.6
Alarm and Annunciations:
The complete alarm and annunciations system shall be provided to indicate the following. (a) Under protection (b) Over protection (c) Over current (d) All failure Transformer rectifier shall be supplied with a continuous signal light which will go out at loss of AC input. In addition to this, T/R unit should give annunciation for Auto and Manual mode of operation by continuous signal light. T/R unit should also indicate the failure of each fuse in bridge rectifier and two DC output fuses by an independent LED. One common signal for all the above annunciations is to be provided for remote annunciation in control room. 7.1.7
Additional features:
(a) TR unit interruption: TR Units should be provided with inbuilt electronic current interruption facility for auto mode operation. Programmable interrupter ON/OFF cycle varying in any ratio from 1 sec. to 999 sec.
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shall be made available at TR unit for operation of the interruption circuitry. (b) Annunciation for Fuse Fail: TR unit should be provided with electronic fuse fail Indicator. The fuse fail indicator should sense signals from each fuse in series with the semi-conductor devices in the rectifier circuit as well as each fuse in DC output circuit and on its failure, it should identify the fuse failed with the help of an independent LED for each fuse for local visual alarm. (c) TR unit remote monitoring: TR unit shall be provided with Transducers for providing 4-20 mA output signals required for remote monitoring unit (RMU) interface for remote monitoring of TR unit output voltage and current. Necessary terminals are to be provided at suitable locations of the TR unit panel for easy termination of onward wiring by others for remote monitoring purpose. 7.1.7
Fabrication and General details:
a) The enclosure of TR unit shall be suitable for free standing, floor mounted type with selfsupporting structure and provided with integral base frame at bottom having compartments to house contain main transformer, auto-transformer, DC choke, etc and also to house the SCRs/,Diodes, indicating meters, protective devices, electronic control circuits/control cords etc. The enclosure protection of panel shall be IP-42 as per relevant IEC/IS codes. a) The enclosure of TR unit shall be fabricated preferably from CRCA sheet steel of minimum thickness 2 mm & 3 mm for gland plates. Removable type undrilled gland plates shall be provided at bottom of the panel. Aluminium gland plates shall be used for single core cable entry. Necessary ventilation shall be provided for the cooling purpose of Transformer, Rectifier, etc housed inside the enclosure. b) Suitable hooks shall be provided for lifting the panel. These hooks when removed shall not leave any hole in the panel or imperfections in the paint finish. c) All instruments shall be panel mounted type and back connected. All fuses shall be provided inside the panel and shall be link type. d) All live parts shall be shrouded. This shall ensure complete safety to personnel indenting routine maintenance by opening the panel doors. e) CPTR unit shall be suitable for bottom cable entry and shall be supplied complete with crimping type cable termination lugs and cable glands. Cable terminating facilities shall be suitable for the specified final cable type and conductor size. f)
Terminal blocks shall be arranged for carrying out external cable termination easily, testing, inspection and maintenance. There shall be ample clear space allowed between the terminal
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block and the gland plate for the spreading and termination of external conductors. g) All terminal blocks shall be shrouded or provided with transparent covers. Terminals for different voltages shall be separated by partitions. Cable terminal arrangements for power and control cables may be integrated with a barrier for separation between the same. h) The printed circuit board contact pads will be chromium plated to provide easy conduction and to eliminate contact corrosion. Completed printed circuit boards will be sealed with a circuit card sealant to prevent atmospheric corrosion and fungus contamination. Circuit elements in the control cards shall be derated properly and proper heat dissipation arrangements shall be made in the PCB so that they function properly for full load operation of T/R unit at ambient temperature. 7.2
Anodes 7.2.1
Anodes shall be suitable for outdoor underground application and shall be supplied from
the following types of anodes (a) Mixed metal oxide coated on Titanium wire anode pre-packed with coke breeze backfill at Manufacturer’s factory (b) Long line Conductive Polymer Anode pre-packed with coke breeze backfill at Manufacturer’s factory Technical Requirements of anodes are as follows: (a) Mixed metal oxide coated Titanium wire anode Mixed Metal oxide coated Titanium anodes shall be dimensionally stable and will be supplied in wire with a dimension of 3mm diameter (minimum). Each wire anode shall be supplied with anode lead cable piggy back connected to it i.e there will be connection between the Primary anode and the internal header cable at a minimum of every 3m. The connection shall be multi-step and water proof. The length of the internal header cable shall be sufficient to reach the nearest AJB. The specification of the internal header cable shall be same as anode lead cable given in the section for cable specification. Sl.No. 1 2 3
Description Anode Type Anode Shape & Dimension Anode weight
4
Anode Material
5 6
Anode design life Anode consumption rate to be
Details Dimensionally stable Anode (DSA) 3mm+0.3mm OD As required Commercially pure Titanium substrate, grade 1/2, ASTM B 338, ASTM B 265, DIN 3.7025, 3.7035, overlayed with mixed oxide of noble metals. 25 years 2 mg/A-yr.(min)
SPECIFICATION FOR CATHODIC PROTECTION SYSTEM EQUIPMENT AND MATERIALS
7
8
considered at 100A/M2 C.density Metal Oxide coating thickness weight Optimum Recommended anode current density with
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6gms/m2(min.)
100A/m2
Carbonaceous backfill in soil/sand Rated current output to be 9
10 11 12
13
14 15
considered with coke backfill for string length calculation Electrical Resistivity (ohm Cm) of Metal Oxide Contact resistance of anode to cable Spacing between consecutive anode string to lead cable joints Anode lead cable piggy back connection arrangement to MMO wire anode and its sealing details for a typical joint Consumption rate of coke breeze to be considered Separation distance of Anode
16
from bullet surface Coke breeze fixed carbon content
17
Coke breeze resistivity
30mA/m
10-5 Ohm Cm 0.9 milli ohms(max.) 3m As per Manufacturer’s splice kit connection procedure. Vendor to furnish Detailed Fabrication drawing 1kg/A.Year(min.) 1000mm(min.) 99% (min.) 0.05 to 15 ohm-cm at 23°C, 10 bars.
Anode jacket shall be continuous, permeable, heavy duty, suitable 18
for field handling and direct burial in sand. The jacket shall be made
19 20 21
of nylon or any inorganic material. Protective current density reqd. for coated bullet String Spacing for each bullet Sand Resistivity
(b) Long line Conductive Polymer anode
Adhesive seam bond strength of jacket shall be 800N/25mm
13 mA/m2(Min.) 1m 10,000 ohm-cm for Dry sand 500 ohm-cm for Wet sand
SPECIFICATION FOR CATHODIC PROTECTION SYSTEM EQUIPMENT AND MATERIALS Sl.No. Description 1
Anode Type
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Details Long line conductive polymer anode, Anode flex, 1500-01
Overall OD of anode sting with 2
3 4 5
calcined petroleum coke breeze and its Nylon fabric jacket enclosure Conductive polymer OD Weight including calcined petroleum coke breeze Max. length of each anode flex string Looping of Anode flex with anode
35mm (minimum)
13.2 + 0.5mm 1.0 Kg/m( min.) 300m
6
lead cable and sealing of free end
As per Manufacturer’s standard
7 8
of Anode flex Consumption of coke/carbon Anode Current Rating Separation distance of Anode flex
1kg/A. Year (minimum) 50mA/m (maximum.)
9 10 11 12 13 14 15 15 16
from bullet surface Conductive polymer volume resistivity Coke breeze fixed carbon content Coke breeze resistivity Adhesive seam bond strength of nylon jacket Protective current density required for coated bullet Design Life String Spacing for each bullet Sand Resistivity
7.2.2
1000mm(minimum) 1.1 to 1.9 ohm-cm 99 %( minimum) 0.05 to 15 ohm-cm at 23°C, 10 bar. 800N/25mm 13 mA/m2 (minimum) 25 years 1m 10,000 ohm-cm for Dry sand and 500 ohm-cm for Wet sand
Anode Lead Cable
Each anode to be supplied with different lengths of cables connected to each anode as per the cable length schedule after actual site measurements.
7.2.3
Anode to Cable connection
Anode lead cable conductor shall be crimped with tubular anode at the center of anode or at the ends and shall be sealed to prevent ingress of water at the joint.
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7. 3 Permanent Reference cells a) High purity copper/copper sulphate reference cells with proven high reliability shall be supplied for providing stable pipe to soil potential measurement reference at CP stations, at computerized test station locations and at locations of polarization coupons. b) Permanent reference cell shall be suitable for 5-40 deg.C temperature application in sand and have the following requirements Sl.No. Description 1 Type of reference half cell 2
Backfill material
3
Body
4
Size of cell
5 6 7
Location of half cell Design life : Stability 7.3.1
Details Cu/CuSO4 type. Gypsum powder 75%, Bentonite powder 20% Sodium Sulphate 5% Impact resistance PVC Sch. 80, 2" dia x 16" long Each reference shall be supplied in cotton bag of chemical backfill having overall size 8" diameter x 16" long and complete with 25 M (minimum) cable as per specification. 150 mm from Bullet structure 15 years ±10 mV with 3 Micro-A load
Monolithic Isolating Joints
a) The mounded vessel shall be electrically isolated at all inter connecting inlet, outlet and vapour balance pipe connections using MONOLITHIC ISOLATING joints as per OISD 150 standard. b) Monolithic Joints shall be of 300 Class, Pressure rating suitable for the design pressure. c)
All isolating joints shall be protected from over voltage using explosion proof spark gap arrestors /Surge diverter (as per OISD) of 1KV/100KA rating.
7.4
Junction boxes 7.4.1
Anode Junction Box
A common anode lead junction box (AJB) will be provided to feed TR Unit output current to anode strings. The individual (AJB) for each bullet will have provision for independent current measurement of each anode string output. This will be accomplished by means of individual shunts for each individual anode circuit.
SPECIFICATION FOR CATHODIC PROTECTION SYSTEM EQUIPMENT AND MATERIALS
7.4.2
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Cathode Junction Box
Cathode junction box (CJB) will be required for bonding multiple mounded bullets at drain point. One common CJB shall be provided and shall be installed at one end of the bullet. Drainage cables from each bullet shall terminate at cathode junction box and ultimately it will be connected to negative terminal of TR unit. 7.4.3
Test Junction Box
Test junction box (TJB) cum test station will be required for measurement of potential for each bullet. Separate TJB shall be provided for each bullet and shall be installed at one end along the longitudinal axis of the bullet. Reference cell cables and measurement cables from each bullet shall terminate in its respective Test junction box cum test station. 7.4.4
The enclosure of Junction Boxes shall be structure/wall-mounted type. Shutter should be
provided with closed cell neoprene sealing gaskets. The terminal board shall be of 10mm WT Phenolic laminated sheet on which all terminals and shunts are to be mounted. The terminals shall be made of cadmium plated steel or stainless steel stud nut and washers of suitable sizes. All cable entries shall be through Aluminum double comprehension glands. The external bolt, nuts and clamps to be used for mounting the junction box with back plate/structures shall be MS electro-galvanised or Cadmium plated. 7.4.5
The cable glands shall be FLP double compression type made of aluminum. Enclosure
need to be certified by CMRI. The shutter of the junction box shall be screwed to the body of junction box by using MS electro galvanised/Cadmium plated nut, bolt and washers. The enclosure of the junction box shall be made of cast aluminum. One earthing terminal shall be provided for earthing the junction box. 7.4.6
Monitoring Junction Box
a) All the reference cell cables and measurement cables from each TJB shall be terminated into a single Monitoring junction box (MJB) which will be ultimately connected to TR unit by monitoring cable.
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Monitoring Junction Box shall be suitable for non- classified area applications and shall have the following requirements: (a) Monitoring Junction Box will be installed near the TR Unit and shall be required for monitoring potentials of multiple bullets. The enclosure for the MJB shall be of IP-42 construction made of 12SWG (2.67) WT sheet steel. (b) The enclosure shall be structure/wall mounted type having removable hinged front shutter with one handle and flush type locking arrangement. Shutter should be provided with closed cell neoprene sealing gaskets. The terminal board shall be of 8mm thick Phenolic laminated sheet on which all terminals shall be made of stainless steel stud, nut and double spring washers of suitable size for reference cell/measurement cables. Bottom row of terminals will be utilised for termination of measurement cables and upper rows for the reference cell cable termination from each bullet. All cable entries shall be through Aluminum double compression glands. The external bolt, nuts and clamps to be used for mounting the junction box with back plate/structures shall be MS electro-galvanised or Cadmium, plated. Shutter should be provided with closed cell neoprene sealing gaskets. One earthing terminal shall be provided for earthing the junction box. 7.5
Cables The requirements for the cables to be used for impressed current type cathodic protection system are as follows: 7.5.1
Anode Lead Cable
Anode Lead Cable shall be 1100 volt grade cross linked Polyethylene (XLPE), 10mm2, stranded copper conductor, single core, un-armoured type. The secondary or overall insulation shall be of PVC sheathing jacket over the primary XLPE insulation. Overall diameter of cable including its tolerance limits shall be confirmed by cable manufacturer in their offer. 7.5.2
+Ve and -Ve Header Cable
+ve header and -ve header cables shall be 1100V grade, single core, 95mm2 stranded Aluminium conductor, Aluminium wire armoured, PVC insulated and PVC sheathed cable. 7.5.3
Drainage Cable
Drainage cables shall be 1100V grade, single core, 50mm2, stranded Copper conductor, Aluminium wire armoured, PVC insulated and sheathed cable.
SPECIFICATION FOR CATHODIC PROTECTION SYSTEM EQUIPMENT AND MATERIALS
7.5.4
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PDB to TR Unit Power Supply Cable
Power supply cable shall be 1100V grade, 3-core, 25mm2 stranded Aluminium conductor, Aluminium wire armoured, PVC insulated and sheathed cable. 7.5.5
Earthing Cable
Earthing cable shall be 1100V grade, single core, 35mm2 stranded Aluminium conductor, unarmoured, PVC insulated and sheathed cable. 7.5.6
Measurement and Permanent Reference Cell Cables
(a) The cables between bullet and TJB shall be 1100 V grade, single core, 6mm 2, stranded Copper conductor, screened/ armoured, PVC insulated and sheathed. (b) The cables between TJB and MJB shall be 1100V grade, either 1x25 core or 2x 10 core, 2.5mm2, solid copper conductor, screened, aluminium wire armoured, PVC insulated and sheathed cable. (c) The cables between MJB and TR unit shall be 1100V grade, 10 cores, 2.5mm 2 solid copper conductor, screened, aluminium wire armoured, PVC insulated and sheathed cable. Note: The Cable sizes shall be updated as per the Cathodic Protection Design Basis. 7.6
Calcined Petroleum Coke Breeze Calcined Petroleum Coke breeze shall be of Grade A type and shall conform as per IS-8502 standard.
7.7
Corrosion protection All junction Boxes, PDB and their support structures, MS channels for TR mounting if any, cable marker Posts shall be galvanized & painted in following manner. (a) Surface preparation - Grit/shot Blasted to SA2 1/2 as per swedish standard SIS 055900 (b) Galvanizing - Hot dip or spray galvanized to achieve a minimum zinc thickness of 150μm. (c) Primer Application - Etch Primer with 10 μ DFT based on Polyvinyl Butyral resin + 1 coat of epoxy zinc phosphate primer @40 μ DFT/coat. (d) Paint Application - 1 Coat of 2 Pack high build epoxy with Polyamide hardener cure @100μ DFT/coat followed by 1 Top coat of Acrylic Polyurethane finish paint @40 μ DFT/coat.
SPECIFICATION FOR CATHODIC PROTECTION SYSTEM EQUIPMENT AND MATERIALS
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(e) MS covers for shallow vertical Beds shall be painted with 2 coats of synthetic enamel paint of reputed make. Colour of paint shall be yellow.
8.0
QUALITY ASSURANCE a) The Vendor shall comply with ISO 9001:2008 Quality Assurance System or may be appropriate to the type of contract and his product. b) If the Vendor elects to sub-contract part of the work he shall ensure that only those subcontractors or suppliers are used who can demonstrate that they operate Quality Systems based on ISO 9001 or ISO 9002 as applicable. The vendor shall give his sub-contractors or suppliers assistance in attaining the required standard, if necessary. This shall not relieve the vendor of his responsibility for the quality of the finished work. Owner reserves the right to audit the Vendor’s Quality System. c) The Vendor shall submit a “Quality Assurance Plan” for review within 3 weeks from the date of Purchase Order.
9.0
INSPECTION AND TESTS a) The PURCHASER reserves the right to carry out any number of inspections during manufacturing and witness factory tests. b) Inspection and testing shall be carried out in accordance with the relevant standards. The Inspection Test Plan (QA Plan) shall be submitted to PURCHASER at bid stage. PURCHASER shall require a Factory Acceptance Test (FAT) which he may or may not attend at his discretion. FAT procedure shall be submitted for approval at least three weeks prior to the proposed test activities date will be held. VENDOR shall carry out all tests including but not limited to the following tests as per the relevant standards
9.1
Transformer Rectifier Unit The tests for the transformer rectifier unit shall include but not be limited to the tests listed below Acceptance tests: a)
Visual Inspection: This shall include •
Completeness of the equipment in line with the specification
•
Checking of all settings
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•
All labels provided
•
Dimensional checking
•
Proper mounting of components and neatness of wiring etc.
•
Model number
b)
Insulation tests:
c)
Heat run test: All CPTR units shall be subjected to a heat run test performed at rated voltage for period not less than 16 hours prior to the execution of the functional tests
d)
Functional tests: The following functional tests shall be performed on each CPTR unit •
CVCC mode operation testing for constant voltage operation and constant current operation.
•
Auto PSP mode operation.
e)
The current interrupter shall be tested for time interval settings and specified operation.
9.2
Anodes The following tests shall be conducted for Mixed metal oxide coated on Titanium wire anode or Long line Conductive Polymer Anode a) Visual inspection b) Destructive testing c) Chemical analysis d) Electrochemical tests e) Spectrographic analysis f)
9.3
Calibration test for permanent reference cells
Calcined petroleum coke breeze The petroleum coke breeze shall be tested for chemical composition, bulk density, real density, particle size and resistivity.
9.4
Cables The tests for cables shall include but not be limited to the following as per relevant IS/IEC standards a) Routine tests b) Type tests c) Acceptance tests
SPECIFICATION FOR CATHODIC PROTECTION SYSTEM EQUIPMENT AND MATERIALS
10.0
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MARKING 10.1
Transformer Rectifier Unit All panel mounted equipments (e.g. lamps, pushbuttons, switches, meters, PCBs, etc) shall be provided with suitable nameplates. A nameplate of anodized aluminium with black back ground and white letters shall be fixed. Engraving shall be done with groove cutters. Hard paper or self-adhesive plastic type nameplates are not acceptable. Nameplates shall be fastened by screws and not by adhesive. Labels shall be provided for every component on the cards, connecting wires as well as for the terminals in the terminal strip inside the panel.
10.2
Anode Junction Box A nameplate of anodized aluminium with black back ground and white letters shall be fixed to the inner side of the junction box. The nameplate shall carry the following minimum information.
10.3
•
Ground bed current rating
•
Ground bed resistance
•
Connection scheme
•
Distance from pipeline in metres
•
Distance from CP station in metres
Cathode Junction Box A nameplate of anodized aluminium with black back ground and white letters shall be fixed to the inner side of the junction box. The nameplate shall carry the following minimum information.
10.4
•
Chainage in km
•
Connection scheme
•
Distance from nearest pipeline in metres
•
Direction of product flow
Cables
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The cable shall be wound on a drum and packed. The ends of the cable shall be sealed by means of non-hygroscopic sealing material. The cable shall carry the following information indelibly marked in English (all dimensions in metric), on the surface of the cable over sheath (outer sheath) at regular intervals of 1 metre over the entire length for ease of cable identification. •
Reference Standards IS/IEC (whichever applicable).
•
Manufacturer’s name or trade-mark.
•
Type of cable and voltage grade.
•
Number of cores.
•
Nominal cross sectional area of conductor.
•
Cable code.
•
Cable length.
•
Year of manufacture.
The means of marking shall be as per IS-10418/IEC 60446. The start and finish numbers of the metre marking shall be labeled on the drum. Actual lengths of cable on a drum should be about 3 percent more than specified, on the purchase order. No negative tolerances will be entertained. 10.4.1 Cable Drum Construction and Marking a. The cable drum construction shall be in accordance with IS:10418 standard, good engineering practice and each cable drum shall be suitable for transport, long term storage and cable laying operation. The Manufacturer shall inform company of the special conditions for storage and pulling of the drums. b. EPIC Contractor / Supplier will be entirely responsible for any claim arising which is attributable to defective and / or insufficient packing. c. Cable drums shall be protected to prevent cable damage, tampering and water penetration. d. The inside diameter of the drum on which every cable is wound shall, in general, not be less than twice the minimum permissible bending radius. Every cable drum shall have, on its outside surface, a nameplate, label or indelible wording clearly indicating the information specifically indicated by the contractual documents, applicable codes or project specification. The minimum information is: •
Reference Standards IS/IEC (whichever applicable).
SPECIFICATION FOR CATHODIC PROTECTION SYSTEM EQUIPMENT AND MATERIALS
11.0
•
Manufacturer’s name or trade-mark.
•
Type of cable and voltage grade.
•
Number of cores.
•
Nominal cross sectional area of conductor.
•
Cable code.
•
Length of cable on the drum.
•
Number of lengths on the drum (if more than one)
•
Direction of rotation of drum (by means of an arrow)
•
Gross mass
•
Country of manufacture; and
•
Year of manufacture.
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PACKING AND DESPATCH a) All the equipment/material for CP system shall be despatched in wooden crates. b) All the equipment shall be divided in to several sections for protection and ease of handling during transportation. The equipment shall be properly packed for transportation by ship/rail or trailer. c) The equipment shall be wrapped in polyethylene sheets before being placed in crates/cases to prevent damages to finish. d) Special notations such as ‘Fragile’, ‘This side up’, ‘Centre of gravity’, ‘Weight’, ‘Owners particulars’ etc shall be clearly marked on the package. e) The package shall be completely suitable for outdoor storage in areas with heavy rain/high ambient temperature.
12.0
REFERENCE DOCUMENTS MMPL Doc.No:297440-003-DBS-4001-Rev_C
: Electrical Design Basis
MMPL Doc.No:297440-003-DBS-4002-Rev_B
: Cathodic Protection System Design Basis
MMPL Doc.No:297440-003-DBS-4004-Rev_C
: Specification for Cathodic Protection System Equipment and Materials
MMPL Doc.No:297440-003-DBS-4006-Rev_B
: Specification for Electrical Design & Cathodic Protection System Installation,
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Testing and Commissioning
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