PTS 60.2405 Offshore Marine Safety.pdf

July 14, 2017 | Author: Ramli Disa | Category: Anchor, Subsea (Technology), Drilling Rig, Water Transport, Watercraft
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A guideline for offshore marine safety in Petronas Carigali Malaysia....

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PETRONAS TECHNICAL STANDARDS HEALTH, SAFETY AND ENVIRONMENT

STANDARD

OFFSHORE MARINE SAFETY

PTS 60.2405 OCTOBER 2012

© 2010 PETROLIAM NASIONAL BERHAD (PETRONAS) All rights reserved. No part of this document may be reproduced, stored in a retrieval system or transmitted in any form or by any means (electronic, mechanical, photocopying, recording or otherwise) without the permission of the copyright owner.

PREFACE PETRONAS Technical Standards (PTS) publications reflect the views, at the time of publication, of PETRONAS OPUs/Divisions. They are based on the experience acquired during the involvement with the design, construction, operation and maintenance of processing units and facilities. Where appropriate they are based on, or reference is made to, national and international standards and codes of practice. The objective is to set the recommended standard for good technical practice to be applied by PETRONAS' OPUs in oil and gas production facilities, refineries, gas processing plants, chemical plants, marketing facilities or any other such facility, and thereby to achieve maximum technical and economic benefit from standardization. The information set forth in these publications is provided to users for their consideration and decision to implement. This is of particular importance where PTS may not cover every requirement or diversity of condition at each locality. The system of PTS is expected to be sufficiently flexible to allow individual operating units to adapt the information set forth in PTS to their own environment and requirements. When Contractors or Manufacturers/Suppliers use PTS they shall be solely responsible for the quality of work and the attainment of the required design and engineering standards. In particular, for those requirements not specifically covered, it is expected of them to follow those design and engineering practices which will achieve the same level of integrity as reflected in the PTS. If in doubt, the Contractor or Manufacturer/Supplier shall, without detracting from his own responsibility, consult the owner. The right to use PTS rests with three categories of users: 1) 2) 3)

PETRONAS and its affiliates. Other parties who are authorized to use PTS subject to appropriate contractual arrangements. Contractors/subcontractors and Manufacturers/Suppliers under a contract with users referred to under 1) and 2) which requires that tenders for projects, materials supplied or - generally - work performed on behalf of the said users comply with the relevant standards.

Subject to any particular terms and conditions as may be set forth in specific agreements with users, PETRONAS disclaims any liability of whatsoever nature for any damage (including injury or death) suffered by any company or person whomsoever as a result of or in connection with the use, application or implementation of any PTS, combination of PTS or any part thereof. The benefit of this disclaimer shall inure in all respects to PETRONAS and/or any company affiliated to PETRONAS that may issue PTS or require the use of PTS. Without prejudice to any specific terms in respect of confidentiality under relevant contractual arrangements, PTS shall not, without the prior written consent of PETRONAS, be disclosed by users to any company or person whomsoever and the PTS shall be used exclusively for the purpose they have been provided to the user. They shall be returned after use, including any copies which shall only be made by users with the express prior written consent of PETRONAS. The copyright of PTS vests in PETRONAS. Users shall arrange for PTS to be held in safe custody and PETRONAS may at any time require information satisfactory to PETRONAS in order to ascertain how users implement this requirement

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PTS 60.2405 OCTOBER 2012

Acknowledgement This document was jointly prepared with contribution from the following organizations: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16.

Morris Kho Capt M Hanafi M Ali Capt Muhammad Adiputra Md Nabil b Md Yusoff Capt Paul Aeria Capt Amser Yusuf Daud Capt Maninderjit Singh Bajwa Capt Abd Nasir b Ramli Dr Mohd Hatta Usul Megat Muzafar b Mohd Mokhtar Mohd Khairi Ismail Ng Boon Hock Mohd Fouzi Abdullah Helme Athrah Jaafar Norshidi Fazizi b Mohd Noor Lawrence Sim Hua Chia

GHSED PCSB/DFIN PCSB/SCM PCSB/DFIN PMSSB MISC MISC PMO/PDP GHSED GHSED PCSB/DFIN PCSB/DFIN PCSB/DFIN PCSB/DFIN PCSB/DFIN PCSB/DR

.

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PTS 60.2405 OCTOBER 2012

ABBREVIATIONS AND ACRONYMS

ACAD

AutoCAD

AHT

Anchor Handling Tug

AHTS

Anchor Handling Tug Supply vessel

BMS

Barge Management System

CSR

Company Site Representative

DGPS

Differential Global Positioning System

KP

Kilometer Post

Offshore

Activities being carried out away from land towards the water

OIM

Offshore Installation Manager

Doc. No PTS 60.0110 PTS 60.1501.06 PTS 58.03.01.02 PTS 60.2103 PTS 31.10.00.31 PTS 37.19.10.20

REFERENCED DOCUMENTS Title Logistic Guideline on Health Assessment for Fitness to work Offshore Support Vessel & Marine Support Craft Vetting Procedures Lifting Noise control (amendments/ supplements to ISO 15664) Marine Safety of Mobile Offshore Installations

PTS 37.19.10.31 PTS 37.19.60.20

Helidecks on Fixed and Mobile Offshore Structures Offshore Structures Engineering

PTS 37.91.10.11

Mooring of mobile units

PTS 37.92.10.30

Pedestal cranes (amendments/supplements to API Spec 2C)

PTS 37.92.10.31

Pedestal cranes (amendments/supplements Lloyd's code and BS 2573)

PTS 80.80.00.10

Offshore facilities life-saving appliance requirements (amendments/supplements to SOLAS)

PTS 37.19.10.42

Transportation

5

PTS 60.2405 OCTOBER 2012

PTS 37.19.10.41

Load-Out and Sea Fastening

PTS 37.19.11.10

Determination of Loads on Structures and Sea Fastening During Barge Transportation International Convention for the Safety of Life at Sea Standards of Training, Certification and Watch Keeping for Seafarers

SOLAS STCW

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PTS 60.2405 OCTOBER 2012

TABLE OF CONTENTS 1.0

2.0

3.0

4.0

INTRODUCTION AND SCOPE.................................................................................. 11 1.1

INTRODUCTION AND PURPOSE .................................................................. 11

1.2

SCOPE ............................................................................................................ 11

PERSONNEL RESPONSIBILITIES ........................................................................... 11 2.1

PERSONNEL RESPONSIBILITIES .............................................................. 11

2.2

COMPANY SITE REPRESENTATIVE (CSR) / COMPANY MAN ................ 11

2.3

RIG MANAGER / BARGE OR WORKBOAT MASTER ............................... 12

2.4

POSITIONING SURVEYOR .......................................................................... 13

2.5

PETRONAS MARINE COORDINATOR ....................................................... 14

2.6

PETRONAS MARINE CONTROLLER .......................................................... 14

2.7

RIG / BARGE MOVER .................................................................................. 14

2.8

TOW / AHT/ AHTS MASTER ........................................................................ 15

2.9

MARINE INSURANCE / WARRANTY SURVEYOR ..................................... 16

2.10

OTHER PERSONNEL ................................................................................... 17

VESSEL CREW REQUIREMENTS ........................................................................... 17 3.1

MANNING ...................................................................................................... 17

3.2

COMPETENCY AND SCREENING .............................................................. 18

3.3

WORKING HOURS AND DAYS ................................................................... 19

VESSEL REQUIREMENTS ....................................................................................... 19 4.1

SELECTION PARAMETER........................................................................... 19

4.2

VESSEL AND BARGE AGE ......................................................................... 20

4.3

BARGE SPECIFICATION ............................................................................. 20

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PTS 60.2405 OCTOBER 2012

5.0

6.0

7.0

RIG / BARGE MOVE .................................................................................................. 20 5.1

INTRODUCTION ........................................................................................... 20

5.2

REQUIREMENT ............................................................................................ 20

5.3

PRE MOVE PREPARATION / PLANNING ................................................... 21

5.4

ONSITE PRE MOVE PREPARATION .......................................................... 23

5.5

RIG / BARGE TOW ....................................................................................... 29

5.6

ARRIVING NEW LOCATION AND MAKING APPROACH .......................... 30

5.7

WORK BOAT / DIVING SUPPORT BOAT OPERATIONS .......................... 35

5.8

DRILL SHIP OPERATIONS .......................................................................... 37

TOWING ARRANGEMENT AND OPERATION ........................................................ 37 6.1

TOWING ARRANGEMENTS ........................................................................ 37

6.2

EMERGENCY TOWING ARRANGEMENTS ................................................ 38

6.3

TOWLINE CATENARY ................................................................................. 39

6.4

PASSAGE PLANNING FOR TOWING ......................................................... 39

6.5

INTER – FIELD TOW .................................................................................... 40

6.6

TOWING WITH ANCHOR WIRES ................................................................ 40

6.7

DURING TOW PASSAGE ............................................................................. 40

6.8

LOCATION APPROACH ............................................................................... 40

6.9

SAFETY REQUIREMENTS ........................................................................... 41

MOORING EQUIPMENT ............................................................................................ 41 7.1

ANCHOR MOORING ARRANGEMENT ....................................................... 41

7.2

WINCHES / WINDLASS ................................................................................ 42

7.3

CLOSED CIRCUIT TELEVISION MONITORS (CCTV) ................................ 42

7.4

TENSION METERS ....................................................................................... 42

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PTS 60.2405 OCTOBER 2012

8.0

9.0

7.5

FOOTAGE COUNTERS ................................................................................ 43

7.6

FAIRLEADS AND ROLLERS ....................................................................... 43

7.7

ANCHOR CABLES ....................................................................................... 43

7.8

ANCHORS ..................................................................................................... 44

7.9

PENNANT WIRES ......................................................................................... 45

7.10

ANCHOR BUOYS ......................................................................................... 46

7.11

SPRING BUOY .............................................................................................. 48

7.12

BUOY CATCHER .......................................................................................... 48

7.13

OTHER FITTINGS ......................................................................................... 49

ANCHOR PATTERN .................................................................................................. 50 8.1

DRAWING OF ANCHOR PATTERN ............................................................ 50

8.2

FACTORS TO CONSIDER FOR ANCHOR PATTERN ................................ 50

8.3

ANCHOR PATTERN APPROVAL ................................................................ 51

ANCHOR HANDLING OPERATIONS ....................................................................... 51 9.1

ANCHORING RESTRICTION ....................................................................... 51

9.2

ORIENTATION OF ANCHORS ..................................................................... 54

9.3

CONTINGENCY PROCEDURES .................................................................. 54

9.4

EXTENDED HOURS ANCHORING OPERATIONS ..................................... 55

9.5

ADVERSE / MARGINAL WEATHER PRECAUTIONS ................................ 55

9.6

TRANSFERRING ANCHOR FOR RUNNING ............................................... 56

9.7

RUNNING ANCHOR ..................................................................................... 57

9.8

DECKING OF ANCHOR ................................................................................ 59

9.9

CASTING OF BUOY ..................................................................................... 59

9.10

SOFT MOORING TO JACKET LEG ............................................................. 60

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PTS 60.2405 OCTOBER 2012

9.11

PRE – TENSIONING OF ANCHOR .............................................................. 61

9.12

ANCHOR RETRIEVAL PROCEDURE .......................................................... 62

9.13

PERMANENT CHAIN CHASER (PCC) SYSTEM ........................................ 63

10.0

SAFE WINCH OPERATIONS .................................................................................... 67

11.0

SAFE OPERATIONS ................................................................................................. 68

12.0

APPENDIX ................................................................................................................. 69

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PTS 60.2405 OCTOBER 2012

1.0

INTRODUCTION AND SCOPE

1.1

INTRODUCTION AND PURPOSE This standard provides the minimum safety requirements for all Offshore Marine activities conducted at PETRONAS and JV‟s (with operational control) facilities and installations. It shall be used in conjunction with local procedures, guidelines, regulations and statutory requirements.

1.2

SCOPE This Standard covers anchor handling, towing, mooring, securing and lifting for Offshore Marine Vessels, including but not limited to, Pipe Laying Barge, Derrick Barge, Transportation Barge, Accommodation Barge, Anchor Handlers, Dynamic Positioning Vessels, Diving Support Vessels, Supply Vessels, Landing Craft (LCT), Workboats, Tugboats, Survey Vessel , Harbour Craft, MODU, MOPU and Crew Boats for domestic and international operations. For international operation, these requirements are to be complied with in addition to the specific requirement of local legislation.

2.0

PERSONNEL RESPONSIBILITIES 2.1

Personnel Responsibilities The following describes the responsibilities of key personnel involved in the moving, towing, mooring and anchor handling operations. During barge or work boat or rig relocation and anchor handling operation these individuals will work in conjunction with the other personnel to ensure that proper guidelines are followed and that the necessary actions are taken by relevant personnel.

2.2

Company Site Representative (CSR) / Company Man 1)

2) 3) 4) 5)

6)

Is the designated PETRONAS representative onboard and as such is the sole point of contact through which all rig/barge move notifications / exterior communications will pass. In consultation with the relevant parties, he has the ultimate authority to stop any unsafe operations from being carried out at site To be accountable for PETRONAS‟ interest for the safe and efficient operation at site. To promote HSE through implementing and leading good HSE practices at work site to achieve incident-free operations. Shall liaise with the Rig Manager / Rig Mover with regard to rig move, towing, mooring and anchor handling activities. Shall liaise with the Barge Master / Barge Mover/Work Boat Master and Marine Controller with regard to barge move, towing, mooring, anchor handling and work boat activities. Shall liaise between contractor rig / barge personnel and the PETRONAS

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PTS 60.2405 OCTOBER 2012

7) 8) 9)

2.3

management onshore. Shall be responsible for accepting the vessels (Tow / AHT / AHTS) on / off hire figures if applicable. Shall be responsible for accepting the final position at the location. To obtain Location Approval Certificate and an overview of infrastructure on the seabed including verified information on sea bottom conditions and any obstructions and disseminate this information to rig manager / barge master, rig mover and marine controller.

RIG MANAGER / BARGE OR WORKBOAT MASTER 1) 2)

3) 4)

5) 6)

7) 8) 9) 10) 11) 12)

13) 14) 15)

16) 17)

18) 19) 20) 21)

Overall charge of rig / barge / work boat. Shall retain his overall authority during the period of a location move and will decide when it is safe and practicable to commence the operations in consultation with the attending Rig / Barge Mover or Marine Controller. To ensure a continuous log of events is maintained. To ensure the correct deployment of competent personnel to operate the jacking system (for jack-up rig), winches and to connect / disconnect the towing vessels. To conduct Emergency Drills and Safety Meetings as required by regulatory bodies and PETRONAS. To ensure that the minimum manning policy is complied with regards to separate marine personnel required for marine operations such as moving, towing and anchor handling operations. To ensure that all relevant authorities are informed of the move as appropriate. To ensure all navigation charts and publications required for the move are on board prior to commencement of the operations. Shall ensure that all pre‐rig move checklists have been completed and signed off to his satisfaction prior to jacking down (for jack-up rig). Solely responsible for the safety of the rig / barge / work boat and crew at all times. Responsible to the CSR for the correct deployment and direction of personnel during all operations on deck and other areas as per this requirement. To advise Rig / Barge Mover / Marine Controller accordingly for any changes on the draft and trim of the rig / barge / workboat that may create a change in her characteristic. To execute anchor handling operation in a safe and professional manner in accordance with the requirement. To ensure the safety of client facilities such as platform, pipeline and etc. at all times. To liaise with CSR in consultation with rig mover and marine controller before any deviation from approved plan due to unforeseen circumstances that takes place throughout the rig /barge move operation, as and when required. To ensure that the mooring and anchor handling equipment are regularly inspected, certified and remain in an operational condition at all times. To adhere to the requirement on horizontal / vertical minimum distances to installations and pipelines on the seabed for anchors and anchor wires lines as per approved anchor pattern / plan. To carry out / make available risk analyses. To obtain verified information on sea bottom conditions and any obstructions. To obtain verified weather and wave data. Establish communication, inform installation about the operation status at all

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PTS 60.2405 OCTOBER 2012

22)

2.4

times. Endeavour to use dedicated Very High Frequency (VHF) channels for communication between installations.

POSITIONING SURVEYOR The Positioning Surveyor shall be responsible for supplying, setting up and maintaining the survey equipment. The Positioning Surveyor shall review the move procedures especially the positioning tolerances, and will accurately log the units‟ position and heading throughout the move and anchor handling operations. He / she shall: 1) 2) 3)

4)

5)

6) 7)

8)

9) 10) 11) 12) 13)

Prepare a report that captures all the important aspects of the positioning operations. Install, if possible, any and all required navigation packages on AHT / AHTS prior to their departure from the present location Responsible for providing constant data showing the position of the unit at all times during the move and during anchor handling and ensure that all relevant field data is displayed on the navigation display screens as appropriate. To utilise Differential Global Positioning System (DGPS) to ensure that the jacket, pipeline and anchors are positioned within the target area and corridor as specified by PETRONAS. The survey team onboard the rig / barge will operate the survey system to monitor and guide the movements of the barge and anchor handling tugs and ensure that safety zones around existing structures and pipelines will not be entered by the rig‟s / barge‟s anchors. Liaise with the Rig / Barge Mover and Marine Controller with respect to navigation equipment status and position confidence. Perform system checks to prove navigation system confidence prior to commencement of the move and at intervals during the move operation. Any failures / shortfalls in navigation equipment must be immediately reported to the Rig / Barge Mover and Marine Controller. Ensure that all positioning systems on the unit and AHT / AHTS vessels are operating correctly and highlight at an early stage any positioning problems which could delay the operations or place any assets at risk. Maintain detailed logs of all movements of the unit as advised by the Rig / Barge Mover and Marine Controller. Ensure that positioning equipment set up, operations and equipment demobilization on the unit are carried out in a safe manner. Immediately report all survey related incidents to the Rig Manager, Rig / Barge Mover and Marine Controller. Check and endorse the final rig / barge position. The scope of work of surveyor comprises of the following: i. ii.

iii.

Provision of management facilities and survey related resources and preparation of positioning and survey procedures. Provision of DGPS Position system. The DGPS system should be made available both on the installation rig / barge and two associated anchor handling tugs. Provision of Barge Management System (BMS) onboard the installation barge, to continually monitor display and record barge position, and

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PTS 60.2405 OCTOBER 2012

iv.

v. vi. vii.

display barge and anchors relative to existing facilities. Provision of Tug Management System onboard the two (2) Anchor Handling Tugs (AHT‟s) to continually monitor and display the Tug position relative to anchor drop point, as prescribed from the rig / barge, and permit all anchor drop and recover locations to be recorded automatically on the rig / barge. Additionally to provide for control and display at AHT position, heading and speed at all times onboard the rig / barge. All anchor drop and recovery positions to be recorded and plotted and documented. Provision of the BMS Display to the winch operators for correct control of barge position along the proposed pipeline. (for pipe lay barge). Provision of portable Ultra Short Base Line (USBL) acoustic positioning system and mini beacons to track the position of a Remotely Operated Vehicle (ROV) deployed from the barge and to position subsea structures.

2.5

PETRONAS MARINE COORDINATOR 1) Responsible to approve anchor pattern for ongoing and upcoming projects prior to commencement of anchor handling activities 2) Responsible to screen appointment of Marine Controllers for PETRONAS 3) Liaise with PMT Management on ongoing offshore activities on the need to basis 4) This position resides in the main office as part of the operational team

2.6

PETRONAS MARINE CONTROLLER 1) 2)

3)

4)

5) 6) 7)

2.7

Shall be responsible to the CSR. He shall monitor and coordinate marine operation at site is carried out in accordance with PETRONAS requirements. To coordinate when it is safe and practicable to commence operations in consultation with the Barge Master / Rig Mover/Work Boat Master and the Tow/AHT/AHTS vessel Master with reference to relevant approved procedure. Any deviation shall require approved Management of Change (MOC). Responsible for ensuring all marine operations are carried out safely to safeguard people, the integrity of all subsea facilities, assets and environment including minimizing cost impact. To adhere to the requirement on horizontal / vertical minimum distances to installations and pipelines on the seabed for anchors and anchor wires lines as per approved anchor pattern / plan. In consultation with CSR and PETRONAS Marine Coordinator, Marine Controller may approve changes to anchor pattern to suit current operational needs. To ensure that all the operation is adhered to planned procedures, international and local regulations. To provide information and updates on marine activities as required.

RIG / BARGE MOVER The Rig / Barge Mover appointed are responsible for all aspects of the moving, towing, mooring and anchor handling operation and as such his appointment should be recorded in the logbook. He shall be competent in all aspects of jack – up (rig mover) movement including

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PTS 60.2405 OCTOBER 2012

towing, afloat, stability, seaworthiness, navigation, appraisal of weather and passage planning. i. ii.

iii. iv.

v.

vi.

vii. viii. ix. x.

xi. xii. xiii.

xiv.

2.8

Shall have suitable jack – up experience and a working knowledge of jacking operations. (Rig Mover) Shall review the planned routing and highlight any shallow patches, underwater obstructions or hazards to navigation that may lie in or in the proximity of the intended towing route. To discuss the towing route with the appointed towing vessels. To ensure the rig / barge is ready for tow by inspecting the following, but not limited to; Sea Fastenings, Mooring Systems, Tow Equipment and Arrangements, Stability and Load Distribution and Watertight Integrity Plan. To be familiar with the details of the arrival location, water depth, soil details, anticipated penetrations and recommendations detailed within the Location Approval Certificate. To be familiar with the positioning detail of the new location; platform configuration if applicable, details of position tolerances and potential platform interference. To be familiar with the technical capabilities of the jacking system. (Rig Mover) To brief the anchor handling vessels on the procedures to be followed for the rig / barge move. To execute anchor handling operation in a safe and professional manner in accordance with the requirement. To be responsible for the correct deployment of anchors associated with the operations and should ensure that the equipment provided is fit for purpose. To control the movement and actions of all vessels associated with the operations after consultation with the Rig Manager and Marine Controller. To communicate with assisting vessels on VHF radio. To ensure that any and all additional marine equipment provided for mooring i.e. pennants, shackles, anchors, buoys, etc, are certified and correctly recorded upon deployment together with the purpose for which the equipment is deployed. To ensure that all unused items of mooring equipment are correctly manifested for return on completion of the operations.

TOW / AHT/ AHTS MASTER The vessel Master(s) will at all times be responsible for the safety of their crew, vessel(s), and where towing, the safety of the tow. 1)

2)

3)

4)

The designated lead towing vessel will be responsible for the tow and routing while underway and will give direction to any secondary vessel(s) involved in the towing operation. To have a clear understanding of the operations that they are to engage in and have input at the pre move meeting or be advised of its content by the Rig / Barge Mover / Marine Controller. To confirm that all machinery and propulsion systems are operational / available and that their vessels are adequately manned to carry out continuous 24‐hour operations. To ensure their vessels are fully stocked with fuel, lubes and other essentials for

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PTS 60.2405 OCTOBER 2012

5)

6)

7)

8) 9)

10) 11) 12) 13) 14) 15) 16) 17)

2.9

at least 7 days continuous operation. To ensure that crews, when working on deck, are suitably dressed with the correct PPE for the job at hand; Hard Hat, Safety Boots, Safety Glasses and a Life vest, etc. To ensure that the appropriate navigation warnings are transmitted at regular intervals throughout the passage, to warn other vessels of the rig / barge position and progress. To continuously monitor water depth during the operations and at all times is aware of vessel and tow draft relative to available water depth, sea height and tide. To report to the Rig / Barge Mover for any change in condition onboard his vessel that may affect the operation. Responsible for ensuring all move and anchor handling operation is carried out in accordance to safe working practices and observe good seamanship. To ensure that all anchor handling equipment is tested, inspected and in good order. To maintain the rig / barge towed in a safe position throughout towing operation. To ensure that the equipment / machinery are regularly inspected, certified and remains in operation condition. To ensure compliance with the minimum manning requirements. To ensure that planned operations shall be performed within current provisions for working hours and rest periods. To ensure that a safe Job Hazard Analysis has been performed in accordance with the work specification. To ensure that passage planning is carried out and made available prior sailing out to location while on tow. To comply to PETRONAS instructions to Masters of Marine vessels

MARINE INSURANCE / WARRANTY SURVEYOR The Marine Warranty Surveyor, when in attendance, shall issue a Towage Approval Certificate when he is satisfied that the unit is secured and ready for move operations. He or she shall: 1) 2) 3)

Monitor, approve and record the rig‟s transit stability as calculated by the Barge Engineer. Ensure compliance with Marine Insurance. Review all rig move procedures, the towing vessels and routing and provide advice and comment as appropriate. May carry out physical inspection on: i. ii. iii. iv. v. vi. vii.

Internal and external of rig / barge. Cargo and its sea fastening. Tow / AHT / AHTS involved in towage operations. Documentation and certification of rig / barge and Tow / AHT / AHTS. Review departure and arrival stability calculations. Review Operation Manual to ensure the unit is being operated within criteria set out in the document. Review qualifications of personnel in command of the rig / barge and Tow / AHT / AHTS to ensure they are qualified to perform the work.

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PTS 60.2405 OCTOBER 2012

2.10

OTHER PERSONNEL 2.10.1 Rig / Barge Engineer The Rig / Barge Engineer will have the responsibility of ensuring the correct operation of the unit‟s marine systems and equipment during the operations. He or she: 1)

2) 3)

To provide an Afloat Stability calculation prior to commencement of the move and will provide stability calculations in the elevated and preload conditions as appropriate ensuring that any changes to the loading and distribution of weights upon the rig are accounted for. Shall ensure the correct deployment of competent personnel and establish good communication procedures between his personnel. Shall ensure that all personnel are fully briefed on their duties and responsibilities with regards to the operations.

2.10.2 Anchor Foreman 1) To ensure that anchor handling operation are carried out in a safe manner. 2) To ensure that the barge mooring equipment is regularly inspected, certified and remains in an operational condition at all times. 3) To ensure that anchor handling operations are carried out according to approved anchor pattern. 4) To liaise with Barge Superintendent in all areas involving anchor handling operations. 5) To liaise with Surveyor to ensure that anchor positions are in accordance with approved anchor pattern. 6) To liaise with AHT Master and control all barges, AHT and anchor movements. 2.10.3 Hoist Operator 1) 2) 3)

3.0

To ensure that anchor hoist equipment is in good operation condition. To monitor anchor wire tensions, footage counters and barge position during all barge movements. To ensure that barge remains on proposed route at all times.

VESSEL CREW REQUIREMENTS 3.1

MANNING 3.1.1 AHT for pipe laying or any activities that require 24 hrs operations for any period of time – 2 sets of crew, with a total of minimum 17 personnel (see table 1 below). Chief Officer for night shift – minimum 2 years experience in anchor handling operations 3.1.2 Construction crew on board will follow requirements as per respective contract 3.1.3 For dynamic positioning vessels – As per IMCA minimum manning requirement of 3 personnel for normal hours (1 x Master, 1x senior DPO, 1x

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PTS 60.2405 OCTOBER 2012

junior DPO) / 6 personnel for 24 hrs operations as per Table 2 (DP Operations for 24 hrs) below

Table 1 – Day and Night shift crew on board the ship (24hrs operations) No. 1 2 3 4 5 6 7 8 9

DAY Captain Chief Engineer Officer Engineer Bosun Able Bodied Able Bodied Oiler

NIGHT Captain OR Chief Officer st 1 Engineer Engineer Officer Able Bodied Able Bodied Able Bodied Oiler Cook

TABLE 2 – DP OPERATIONS for 24 HRS No. 1 2 3 4 3.2

DAY NIGHT Master with Senior DPO cert Senior DP operator Senior DP operator Junior DP operator Junior DP operator Electronic Technical Officer (ETO)

COMPETENCY AND SCREENING Vessel crew shall meet the competency requirement as per STCW 1995– Standard Training Certification for Watch keeping, issued by International Maritime Organisation (IMO), as amended to Manila Convention 2010. A screening process is required to address and verify the following requirements: To verify that the crew engaged is capable to carry out the job To ensure that the documentations are valid To ensure that the person is familiar with the job and possess the necessary skills and experience To ensure the understanding of PETRONAS policies

PETRONAS contract holder shall ensure: i. ii.

iii.

iv.

The Master and the senior officers must have a minimum of two years oil and gas experience. For those with less than 2 years in oil and gas industry shall be subjected to the following mitigations upon approval by PETRONAS top management: (a) familiarisation exercise by doubling up that position for a period of minimum 2 weeks OR (b) engaged in a lower position until he acquires the 2 years requirement. Assessment during familiarisation exercise shall be conducted by the Master in command. The Contractor shall provide the required documents to the contract holder which includes but not limited to - medical report, certificate of competency (deck officer/engineers as per STCW 1995 as amended to Manila Convention 2010), certificate of watch keeping (able seamen, oiler), certificate of recognition for foreigners (discharge book, curriculum vitae, basic rigging and slinging training (deck crew), , food handling (cook), offshore safety passport and (if required) helicopter underwater escape training (crew change using helicopter) The Manager of the contract holder shall be accountable to approve the acceptance of the vessel crew

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PTS 60.2405 OCTOBER 2012

3.3

WORKING HOURS AND DAYS Working hours /rest hrs to comply with – PTS Management of Fatigue in the workplace, Section 3.6 Seafarers, with the following requirements. The limits on hours of work or rest shall be as follows: Maximum hours of work shall not exceed: i. 14 hours in any 24-hours period; and ii. 72 hours in any seven-day period. or Minimum hours of rest shall not be less than: i. 10 hours in any 24-hours period; and ii. 77 hours in any seven-day period.(ILO convention no.180, article 5) Hours of rest may be divided into no more than two periods, one of which shall be at least six hours in length and the interval between consecutive periods of rest shall not exceed 14 hours. i. Marine crew – (a) Field Support vessel (at location standby vessel) including barges – a maximum of 60 days onboard and minimum of 10 days leave (b) Sector run vessel – including drilling support vessel, a maximum of 90 days onboard and minimum of 10 days leave ii. Construction – 60 days maximum on with a minimum of 1 week break on land

4.0

VESSEL REQUIREMENTS 4.1

SELECTION PARAMETER The selection procedure for the anchor handling tugs is important for the work to proceed as planned. The following parameters shall be considered in determining a suitability of vessel specifications: i. Towing: 1. 2. 3. 4. 5. 6.

The size, type and characteristics of the vessel to be towed. The geographical area of the move with particular reference to weather patterns or hazards and navigational difficulties. Probable duration of tow. The availability and conditions of towing vessels for the operation. Propulsion availability on the tow. Commercial pressure such as value of the tow, necessity to meet particular deadlines, time to prepare the tow and for the voyage. ii. Anchor Handling:

a) Water depth and bottom conditions at the mooring site to determine the vessel and winch power. b) Estimated maximum sea / swell height, wind force and current to determine the vessel size, engine and thruster power.

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PTS 60.2405 OCTOBER 2012

c) The type and weight of anchor to be used to determine size of roller and deck space. d) Method of deployment either by permanent chaser or buoyed system to determine winch power, drum capacity, stopper size and type. e) The need to run piggy back anchor to determine deck space and pennant storage capacity. f) The need to handle extra chain to determine locker capacity and gypsy size. g) Barge / rig winch type and pay out speed. h) The need to run specialized mooring, combination support or preload to determine deck space, work drums, storage reel capacity and numbers of combination stoppers.

4.2

VESSEL and BARGE AGE Contract - The age of vessel/barge shall not be more than 15 years at the end of charter period for a long term charter (contract one year & more), and not more than 25 years for a short term charter (less than one year). Refurbished Vessels/Barges (more than15 years old): A vessel/barge of 15 years or more that has undergone a complete and extensive refurbishing within the last 5 years. The refurbishing shall include where applicable, but not limited to, accommodation, complete overhaul/change out of engines, winches or anchor handling winches, rotating equipment, new electrical system, new plumbing, new safety facilities and equipment, cleaning and re-coating of all tanks and the like. The barge must be certified by the Classification society/Flag State as deemed fit for duty (see Appendix 3). Refurbished barges shall be for short term contract only.

4.3

5.0

BARGE SPECIFICATION Any modifications from the original design, i.e. pontoon/dumb barge to pipe lay/ crane barge or work barge shall be re-examined and approved by Classification Society. A new certificate of class shall be issued based on the new specification.

RIG / BARGE MOVE 5.1

INTRODUCTION This section describes procedures for rig move for Jack – up, Tender and Semi – submersible rig. It also includes procedures on barge movement when performing various engineering works at offshore facilities.

5.2

REQUIREMENT

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In protecting PETRONAS interest and to ensure safe and efficient operation, the presence of PETRONAS Marine Controller onsite is required prior to the execution of anchor handling operations and other high risk activities deemed fit. The following activities but not limited to, should have the presence of PERONAS Marine Controller: 1. Anchoring activities in restricted area 2. Approaching platform 3. In field towing 4. Barge crawling within the field and in the vicinity of other barges and other subsea facilities; and 5. Salvaging operations within 500 meters of gazette area and/or close proximity to subsea facilities The requirement for Marine Controller is optional for Dynamic Positioning 2 (DP2) operated vessel and above (e.g. DP3, DP4, etc) 5.3

PRE MOVE PREPARATION / PLANNING Rig / Barge move preparation / plan shall be carried out by the rig/barge owner and approved by PETRONAS Project Manager / Contract Holder. In preparing a rig / barge move, the rig / barge owner shall consider and carry out the following: 1) 2)

3) 4)

5) 6) 7) 8) 9) 10) 11) 12)

5.3.1

Time of the move and duration of stay in the new location with emphasis on expected weather and tidal conditions. All towing vessel have sufficient consumables i.e. Fuel, lubricating oil, hydraulic oil, drinking water and food for intended duration of the move plus a 25 % reserve. Sub-sea survey report - any shallow gas, seabed obstructions, nature of the bottom and expected penetration. Towing route plan taking into account prevailing weather, navigation aids enroute, proximity of shoals and other navigation dangers, towing draft, and a contingency plan to cater for deteriorating weather, equipment/machinery failure and port of refuge. Prepare anchor patterns for approval for new locations, taking consideration of departure from present location. Any requirement for divers or ROV. Presence of other marine units in the vicinity Stability calculation to be carried out to confirm capability to carry out the intended job. Pre-Move meeting attended by all interested parties. Rig/barge owner/contractor shall ensure that the rig/barge owner is onboard prior to commencing operations Vessel requirements as per Section 4 of this document Complete the Pre-Move Plan. Any pre-move checklist must be completed and signed off prior to commencing of the actual move.

Additional Preparation / Planning for Jack – up Rig Move

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i.

ii.

iii.

iv. v.

a.

Positioning the rig: For open location – Tolerance, type of fix, night restrictions. For jacket move - The distance from and angle to the jacket is derived at after considering the anchor pattern, previous rig entry, coverage of wells to be drilled and clearance of spud-cans from jacket legs and pipelines at the rig should be 'square-on' to the jacket where possible. (Minimum distance from rig to jacket is not less than 1.524 m or 5 feet.) Standby locations - a surveyed area where the rig can soft pin/ jack down. It is preferable to soft pin the rig in front of the jacket/platform at the approach side where deployment anchors are feasible. Previous rig visit to the jacket - type of rig, position, leg penetration, foot prints. Partial coverage of spud cans of different rig types can caused serious damage to the re-entry spud cans/legs Diving requirements - to clear debris, inspect spud-cans, and inspect spudcan clearance from pipelines, old footprints or other obstructions. Designated anchorage area must be pre-sweep surveyed to ensure no present of debris. If the survey has been done more than 6 months, the area need to be re-surveyed.

Rig Heading Open Location The rig‟s heading is determined after considering the following: i. ii. iii. iv. v.

b.

Winds should carry escaping and flared gases away from the living quarters. Helicopters will want to approach into the wind when landing and taking off. Supply vessels generally moored to the leeward side of the rig. Effect of swell and strong currents on supply vessels difficulty to maintain position if they are from the beam. Drilling mast should not shield the radio antenna from the shore or transmitting station.

Open Location Marking (if applicable) When the rig is moving into an open location, a set of markers are deployed to assist in the approach and positioning. When a night approach is expected, the location and heading markers shall be lighted. The location marker, heading markers and anchor position markers are all incorporated into the approved anchor pattern. The present and utilization of positioning equipment to be made available on board (both on rig & tow vessel) for the barge/rig movement, complication of final entry to the intended location. As such the deployment of markers is optional.

c.

Contingency Plan

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During the pre-move meeting onboard the rig, the pre-determined jack down location must be announced to the Rig mover and rig personnel, should this be required during the move. Among the items to be considered are: ii. iii. iv. v. vi. 5.3.2 i.

ii.

iii.

Additional Preparation / Planning for Tender Assisted Rig Move Each Tender Assisted Rig has its own Standard Anchor Pattern. The patterns are basically similar but there may be slight variation in the angles to suit a particular tender. Anchor patterns shall be drawn in such a manner that shifting of anchor will be kept minimal when moving to or from rigging position and approved by PETRONAS Approving Authority. The tender will be positioned for rigging up/down such that the crane will have maximum reach. a. b.

iv. v. vi.

vii. viii. ix. x.

5.3.3 i. ii. iii. iv. v. 5.4

Possible shelter areas. Localities where the rig may jack down in an emergency. Availability of other vessel en-route. Rig's draft under various weather conditions. Port of refuge

Odd configuration of the platform which may be part of a complex. Limitations of the crane reach.

Position of the tender in drilling position is fixed by the platform heading (for platforms specially built for Tender Assisted Rigs). Requirement for a heavy lift crane barge to carry out the rigging up and/or down where necessary. Requirement for flattop material barges. Although most tenders have the capacity to transport their own drilling equipment, experience has shown that it is more practical to transport the bulk of these equipment using flattop barges during moves. Prepare anchor patterns for rigging down positions at old location, rigging up position/s and drilling position at new location. Any requirement for soft moorings. Any requirement for spring buoys. Any requirement for piggy back anchors.

Additional Preparation / Planning for Barge Move Any requirements for soft moorings. Any requirements for spring buoys. Any requirements for piggy back anchors. Any requirements for diving assistance. Designated anchorage area

ONSITE PRE MOVE PREPARATION

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5.4.1

Jack – up Rig a.

Preparation for Departure from Present Location For jack-up rigs, anchors are run for the purpose of pulling the rig off a jacket or for maintaining her position while retrieving legs in a restricted area. The rig personnel shall ensure that towing, mooring and anchor handling equipment including spares are onboard and in a state of readiness. Prior to commencing anchor handling operations the Rig Mover shall carry out the following: i. ii. iii. iv. v. vi. vii. viii.

b.

Evaluate the immediate and forecasted weather condition. Ascertain that all marine crafts are on location. Call a meeting with all the personnel involved in the move. The final procedure for the forthcoming operations shall be discussed and agreed by all at this meeting. Inspect anchor handling / towing equipment on the vessels. Inspect anchor mooring gears on the rig. Check communication systems. In considering the suitability of weather condition for commencing operations, it is prudent to request the anchor handling vessel to stand off the rig where its motion can be seen as it experiences the full sea condition. A dummy run on a buoy by the vessel may help provide a better appraisal of the situation.

Running Anchors at the Old Location and Lowering Hull After completion of drilling and back-loading activities, anchors are recommended to be run at the earliest opportunity. During anchor handling, all activities on the rig, including use of cranes, should be ceased and concentrated on this operation alone. All jacking activities are carried out by the rig personnel. Jacking of rig should cease while passing/connecting tow wire or anchor handling.

c.

Running Anchors and Connecting Towline There is no particular sequence for running the anchors from a stationery rig. In some congested complexes, the anchor handler may not be able to approach close enough to pick up the stern anchors. A smaller vessel may then be required to run out the anchor wire or pennant to the anchor handler. Upon dropping, the anchors shall be tensioned up to ensure that they are holding thereafter all wires shall be slackened off. Connect up the

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towline to the tug and keep it slack. It is preferable that the tow wire to be transferred to the lead tug when the rig is at about 10 feet air gap.

d.

Lowering Hull Once the rig is secured the hull will be lowered if sea condition permitting. If anchor handling operation and towline connection could not be carried out earlier then the ideal time to do so is when the hull is about 10 feet from the water. It is easier and safer to handle anchors at this level then when the rig is at its working air-gap. If anchors had been run earlier then this is the time to do the final tensioning to confirm that the anchors are holding thereafter should they be slacken off. As the hull is being lowered, pick up the slack on the anchor wire to maintain about 20 kips tension (varies with strength and direction of the wind and current). When the hull enters the water minimum to submerge the sub bottom tanks (about 6 feet draft), a physical watertight integrity check shall be carried out.

e.

Freeing Legs The hull is lowered to a few feet below the floating draft to create additional buoyancy for freeing the legs. The legs are usually freed one at a time. In the deeper penetration location, jetting while pulling legs shall be carried out. Once the leg is free, the leg usually not retrieved completely until all the legs are free. Prior to jack the legs/spud cans clear of sea bed, all anchors are tensioned, tow tug to be on minimal power and ready to receive instruction from rig mover. Time taken to free the legs may be almost immediate or may take a few days depending on the penetration. It is prudent to make a final check on the wind and current to determine the resultant direction in which the rig may lie as the last leg is coming free.

f.

Moving Out / Off Jacket The tug shall pick up the slack on the towline as the last leg is being freed. Excessive tension on the towline is unnecessary. Once the legs are clear from the sea bottom, the tension on the anchor wires alone will pull the rig clear.

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In pipeline congested areas the anchor pattern may be such that the rig maintains its position as the legs are being retrieved.

g.

Anchor Recovery When the rig is well clear of the jacket, anchors shall be retrieved. In order to maintain continuous control of the rig there shall be a proper anchor recovery sequence. In deciding the anchor recovery sequence and the direction in which the tug should lay, consider the following: i. ii. iii. iv. v. vi.

vii.

h.

After having decided on which anchor to recover last, slack on the others to check the rig behaviour. Recover the anchors that no longer hold the rig. Avoid placing the rig immediately upstream of the jacket. Avoid running the rig over the anchor wires. Keep anchor handling vessel away from the tug to avoid fouling and collision. The critical stage is in retrieving the last anchor especially if there are obstructions downstream of the rig. In this situation the tug shall hold the rig upstream while that last anchor is being retrieved. Once the anchor is clear from the bottom the tug will tow the rig clear at slow speed until the last anchor is racked (or wire retrieved if that anchor is disconnected). Alternative method to Departure from existing location (Platform)

i) A primary towing vessel shall be connected to the tow bridal ii) Additional tow to be connected to the secondary towing wire

5.4.2

Tender Assisted Rig / Barge a.

Preparing for Departure from Old Location The rig personnel shall ensure that towing, mooring and anchor handling equipment including spares are onboard and in a state of readiness. Prior to commencing anchor handling operations the Rig mover shall carry out the following: i. ii. iii. iv. v.

Evaluate the immediate and forecasted weather condition. Ascertain that all Marine crafts are on location. Call a meeting with all the personnel involved in the move. The final procedure for the forthcoming operations shall be discussed and agreed upon at this meeting. Inspect anchor handling/towing equipment on the vessels.

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vi. Inspect anchor mooring gears on the tender. vii. Check communication systems.

b.

Recovery of anchors – Leaving Present Location Recovery of anchors shall commence as soon as rigging down is completed. Again suitability of weather conditions should be assessed. If there are anchor wires under the bridge, then these anchors should be recovered first with the tender just clear of the platform. Move the tender well clear from the platform and commence anchor recovery. In order to maintain continuous control of the tender there shall be a proper anchor recovery sequence. In deciding the anchor recovery sequence, consider the following: i.

ii. iii.

iv. v. vi. vii. viii. ix. x. xi.

5.4.3

After having decided on which anchor to recover last, slack down on the others to check the behaviour of the tender. The situation may change with changing wind and current. Recover the secondary anchors first. Ideally it should be planned in such a manner that the first anchor in will be the last anchor out and vice versa. This is to avoid crossing and fouling of pennants. With the secondary anchors recovered, the riding' anchor will be clearly established. Recover the anchors that no longer hold the tender. Connect up the towline when at least two anchors are still down. Avoid placing the tender immediately upstream of the jacket. Avoid running the tender over the anchor wires. Keep anchor handler/s and tug away from each other to avoid fouling and collision. The critical stage is in retrieving the last anchor especially if there are obstructions downstream of the tender. In this situation the tug shall hold the tender upstream while the last anchor is being retrieved.

Semi Submersible Rig Semi submersible rig move preparation / precaution are almost similar with the tender assisted rig move operation as describe earlier, additional points to note are: a.

De – ballasting a. The rig shall be de-ballasted from the drilling draft to the transit draft by emptying ballast tank and maintain about 1 degree of trim by stern to aid in removing all water from these tanks.

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b. De-ballasting operation takes between 4 hours to 10 hours where rig‟s draft will be reduced from 19.8 m (65 feet) to 7.62 m (25 feet); the time taken varies between one rig to another. c.

Rig Manager will ensure during the entire operation the calculated KG will always be less than the allowable KG taking into consideration the free surface effect of the lower hull tanks which can cause an appreciable increase in KG.

d. Slack tanks should be kept to a minimum. It is always the case that all upper tanks are empty first before proceeding with lower hull tanks. e. At the transit draft, racking of anchors to the anchor racks are visible to the rig mover on deck. f.

b.

The sitting of anchor racks is designed to locate near the water line when the rig is afloat at her transit draft.

Recovery of Anchors – Leaving Present Location 1. The anchor recovery sequence is dependent upon current, sea and wind conditions. As a general rule, it is advisable to leave one bow and one stern anchor as the last anchor. 2. This should effectively maintain the rig in position, with one anchor lying upstream and the other downstream to the prevailing environmental loading. 3. Some of the Semi-Submersibles rigs still use the conventional steel mooring buoys and pennant wire attachment to anchors as a method for anchoring and deployment. 4. However, in view of the Semi-Submersible rigs operating in deeper water, most of the rigs adopted the “Permanent Chasing Systems “. 5. In principle, a permanent chasing system is an arrangement whereby a chaser is permanently fitted on each anchor wire.

c.

Anchor Recovery – Wire / Chain Chasing Procedure To properly use a chaser, the anchor handling tug must have sufficient power to strip the wire/chain and recover the anchor. The tug‟s work wire length must be sufficient to care for the prevailing water depth she is going to operate. To retrieve an anchor that has already been set, the following

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procedure should be used: 1. Anchor handling tug steams close to the rig, connects chaser assembly to her work wire. 2. As the tug moves away, pay out work wire as the anchor wire/chain is stripped until a total length of work wire equal to 1.5 to 2 times the water depth is being paid out. 3. Tension the anchor wire/chain up to 200-250 Kips to assist in stripping the wire/chain. 4. Anchor handling tug‟s master ascertains when the chaser has been seated onto the shank of the anchor. Inform the rig before proceeding to breaking out of anchor. 5. Anchor handling tug should move away from the anchor maintaining his tension. The rig windlass operator should slack off wire/chain tension to 150-200 Kips during breakout. 6. After break out the anchor wire/chain is retrieved with the rig‟s windlass until the anchor is racked. 7. Return the chaser and the pennant wire back to the rig. One problem associated with permanent chasers arises when the ground cable of a mooring leg becomes deeply buried. In that event, when recovering anchors, the chaser itself goes underground. It then becomes necessary for the tug to back up over the point where the chaser is buried and attempt to lift it and the cable clear of the seabed and lower it down once again. Repeat the chasing once again. If the pennant wire for the permanent chasing system parted, then recourse must be made to the use of the Shepherds Crook (J Chaser) which every Semi Submersible rig possess. Tow line should be connected when the rig left with the last two anchors. Once the last anchor is clear from the bottom the tug will tow the rig at slow speed until the last anchor is racked. On arriving at new location anchors are deployed as per approved plan.

5.5

RIG / BARGE TOW 1. The rig / barge is underway once the last anchor is lifted off the bottom. However the Rig / Barge mover shall continue to maintain control of the operation until the anchor handling vessel disconnects the last pennant or anchor wire. 2. The rig is then 'On Tow' and the Rig / Barge mover shall clearly inform the Tug master. 3. If no anchors are run then the jack-up rig is 'On Tow' when the last footing is

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cleared from the seabed. 4. When the rig is 'On tow' the responsibility of the tow rests with the Master of the tug. Approved passage plan shall be adhered at all times. 5. During the tow the angle of roll and/or pitch should not exceed those shown on the rig‟s critical motion curve. In the event these limits are approached, the tow course and/or speed must be altered as necessary to keep the unit‟s motions from exceeding these limits. 6. Positions will be requested from the lead tug as required. Positions will be plotted on a navigation chart in order that any possible hazards may be identified. The rigs overall draft shall be communicated to the lead towing vessel. A visual/radar watch is to be maintained by the lead tow vessel and attending towing vessels and targets which may endanger the tow shall be plotted

7. Where risk of collision is deemed to exist then action should be taken according to the International Rules and Regulations for the Prevention of Collisions at Sea. 8. The lead tow vessel will be responsible for transmitting radio navigation warnings on VHF and MF at suitable intervals throughout the course of the tow. 9. The tow passage ends upon arrival off the new location. However, the rig is still "on tow" until the first anchor is dropped. 10. Table 4.1 shows Towing Average Speed using towing vessel with bollard pull matched to tow type in weather condition where wind speed is between 15-20 knots and sea height not more than 3 meters from ahead. Type of Tow

Towing Average Speeds

Twin hulled semi-submersible at transit

5.5 to 6.0 knots

draft Triangular jack-up unit (Three legged type)

4.0 to 5.5 knots

Four leg jack-up

3.5 to 4.5 knots

Barges with beam to length ratio 4-5 or

5.5 to 7.0 knots

shaped bows Barges with square hull

2.5 to 4.5 knots Table 4.1 Towing Average Speeds

5.6

ARRIVING NEW LOCATION AND MAKING APPROACH 5.6.1

Arrival

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1. On arriving off the new location, the tug will shorten her towline, reduce her speed and commence to align her for the final approach. 2. Approach to the stand‐off location near the platform for the commencement of mooring operations shall not be made until: 3. Permission has been received to enter the 500 meter safety zone from the platform OIM. 4. The Manager and the Operators Company Representative have granted their permission. 5. Weather forecasts have been obtained and a weather window has been identified of sufficient duration to allow for uninterrupted operations until the rig has been located in a safe condition. 5.6.2

Jack – up Rig 1. The rig shall establish a stand‐off location (approximately 100m off the platform clear from any obstruction) and where anchors will be deployed to assist in the final move alongside the platform. 2. The tugs will be located to the Rig Mover‟s requirements, such that he may hold the rig steady at the stand‐off location, within tolerance, while the spud cans make contact with the sea bed. 3. Contact between the spud cans and the seabed will be arranged to occur at a period of minimum tidal flow when the combination of the prevailing environmental forces (wind, tide, current) do not adversely affect the control of the unit and allow for accurate positioning. 4. Once the required position has been achieved at the stand‐off location, the hull will be jacked to a minimal draft/air gap and towing vessels re‐deployed/re‐configured as directed by the Rig Mover to facilitate running of the unit‟s anchors. a.

Running Anchors at New Location 1. At the new location it is a standard practice to use anchors for positioning the rig in open location and end-on to jackets. The rig mover may choose to hold the rig in position by using three tugs in open location as long as the BMS equipment on board the tug and slave equipment on the tug & anchor handlers. 2. Prior to any anchor handling operations the Rig Mover and PETRONAS Marine Controller will hold a pre‐task meeting to outline the proposed operation and cover any unusual aspects of the job including hazards that may

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exist. 3. The condition of the anchor winches, both mechanical and electrical, will be checked prior to arrival on the proposed location and confirmed as being in operable condition. 4. Where checks reveal that the equipment is not operating to specifications, the Rig Manager and Rig Mover shall be notified immediately. 5. The Rig Engineer will have ensured that the winches, spoolers and fairleads have been properly lubricated per manufacturer‟s recommendations prior to commencing operations. 6. Anchor winches will be run for the deployment and recovery of anchors and for the positioning of the rig in accordance with established procedures and manufacturers recommendations. 7. Personnel designated to operate the winches will have a have a working knowledge of winch operations. 8. Winch operators will ensure that a hand held radio with spare battery is available at all times during anchor running / positioning operations.

b.

Dropping Anchor 1. A debris clearance and seabed features survey shall be carried out prior to this operation to identify any existing pipelines, subsea structure and obstruction. 2. All personnel involved in anchor running operations should familiarize themselves with the locations of these lines and structures prior to engaging in operations. 3. To avoid incident during this phase of operations, all anchors will be decked on the AHTS prior to running and will remain on deck until such time the AHTS is over the proposed final position for the anchor being handled. 4. If AHTS does not cross any pipeline or any seabed facilities, she has an option to hang the anchor at stern roller 5. Anchors will be deployed from the stand‐off location to the positions as per approved anchor pattern. 6. As each anchor is set, the anchor wire must be tensioned to winch near stall in order to prove that the anchor is holding. If the anchor drags, it should be recovered and

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re‐deploy. 7. When all anchors have been set to the satisfaction of the Rig Mover they will be tensioned up and the towing vessels will be reconnected in readiness for re‐floating the hull.

c.

Moving the Rig with Anchor 1. The hull will be lowered to 2.44 - 3.05 m (8 ‐ 10 feet) draft and watertight integrity rechecked. 2. When watertight integrity has been confirmed, the unit will be refloated and the spud cans retracted from the seabed to a position of approximately 5 feet off bottom. 3. The rig will then be maneuvered under strict control and with extreme caution into final position utilising the anchor winches with the towing vessels assisting the operation as required by slacking the forward winches and taking up slack on the aft winches until such time the unit is positioned within tolerances and to the satisfaction of the Rig Mover. 4. It is recommended that this operation should be carried out at “slack water” and when the environmental forces are not setting the rig onto the platform. 5. The control of the movement of the unit while positioning alongside the platform shall be the responsibility of the Rig Mover who will liaise closely with the PETRONAS Marine Controller. 6. All communications and instructions to winch operators, assisting vessels and the units jacking control room during the positioning operation, shall be given, controlled and coordinated by the rig mover.

d.

Raising Hull and Preloading 1. When in the final position the unit will lower the legs to tag bottom. The hull will then be jacked up to the position required to carry out preloading operations. In anticipated punch through location, preloading may be carried out in water/draft to prevent extreme punch through. 2. Prior to commencing preload operations, the positioning survey contractor shall confirm that the rig is leveled in both the longitudinal and transverse planes and that the position is acceptable.

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e.

Retrieving Anchor 1. On dumping the last pre-load, disconnect the towline and commence recovering anchors. 2. It is safer and more practical to carry out anchor handling operations when the hull is close to the waterline. 3. Like in other anchor handling operations, all marine activities on the rig, including use of cranes, should be concentrated on this operation alone. 4. On recovering of all anchors, the Rig mover releases the vessels marking the end of his role in the rig move.

5.6.3

Tender Assisted Rig a.

Arriving New Location 1. On arriving off the new location, the tug will shorten her towline, reduce her speed and commence to align her for the final approach. 2. On the final approach the Rig mover shall liaise closely with the Tug master to guide the tow into position. 3. Being on different ends of the tow, the Tug master and the Rig mover will have different perspective which tow should be used to its full advantage. 4. Approach is always best with the weather by taking advantage of the wind and current for a better control. 5. At the new location the tender will set up at the rigging-up position first. 6. Anchors are deployed as per approved plan. Running and dropping anchors are similar to jack up rig as describe in 5.6.2.a and b. 7. After setting all the anchors, the wires shall be tensioned up to about 40 kips. This constitutes the initial part of anchor pretensioning. 8. Move the tender alongside the platform for rigging up. 9. If more than one rigging up position is required shifting of the tender shall be carried out in a control situation by keeping sufficient member of anchor down at all times. 10. On completion of rigging – up, the tender shall move to the drilling position. 11. A standard sequence is as follows: o Pull the tender clear from the platform. o Move the tender using anchors only.

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5.6.4

Semi Submersible Rig Arriving preparation / precaution are similar to the jack-up rig in relations to running and dropping anchor as described in 5.6.2.a and b. Additional point to note is: a.

Ballasting 1. Ballasting is carried out in order to take the rig from a transit draft (floating on the pontoons), to the drilling draft (floating on the columns). 2. The general method is to trim the rig to an even keel condition and ballast down to required draft. 3. While ballasting the rig to the stage when the lower hulls and tubular cross braces becomes awash, the stability is greatly reduced; therefore, special attention is to be given to stability checks of the rig between the drafts of 7.62 - 10.67 m (25 35 feet). 4. The free surface effect of the lower hull tanks and/or the upper tanks can cause an appreciable increase in KG. As a guide, the most favourable ballasting is achieved by keeping the number of slack tanks to a minimum. 5. Semi-submersibles rigs, while in the process of ballasting / de-ballasting are known to list suddenly due to improper ballast procedure being followed. 6. On completion of ballasting, the duties of the Rig mover are deemed to be completed. Anchor handlers vessel shall be released.

5.6.5

Barge The approved methods for the execution of various barge move are almost similar with the rig move operation described earlier. Safe move and anchor handling operations are primarily dependent upon the observance of proper seamanship practice and adherence to approved plan.

5.7

WORK BOAT / DIVING SUPPORT BOAT OPERATIONS 1. Work Boats / Diving Support Boat may form part of a barge spread or may work independently. Inspection of these vessels shall be conducted before coming on hire and at regular interval to ensure that they maintain their integrity.

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2. Work boats shall be equipped with a 4 point mooring system independently and their duties quite often require them to moor alongside platforms and jackets. The vessels may moor to a two point or a four point mooring depending on various circumstances.

5.7.1

Two point Mooring 1. This operation generally involves the laying of two bow anchors to hold the vessel into the weather, while the stern is secured to the platform/jacket with soft moorings. The bow anchors shall not be run over pipelines if chain anchor cables are used. 2. All the relevant preparation as mentioned earlier shall be complied with prior to carrying out a two point moor. 3. The following is a general guideline on the execution of a two point mooring without the assistance of an anchor handler. The Master of the vessel however, must be guided by the prevailing weather conditions when executing this operation: (a)

The first anchor position is approached with minimum headway.

(b) The first anchor is let go and the anchor wire/chain is allowed to run. The vessel slowly heads towards the second marker buoy location. (c) At the second marker buoy location, slacking of the first anchor shall be stopped. The second anchor is then let go. The workboat works her stern towards the jacket/platform while adjusting on both anchor wires/chains. (d) When approximately 30.5 m (100 feet) away from the structure, the vessel is brought up to her anchors to ensure that both anchors are holding. (e) Once it has been ascertained that the anchors are holding, the vessel continues to back up towards the jacket. At this stage, the rescue boat/zodiac may be used to run the mooring lines to the structure. 5.7.2

Four point Mooring (1) This operation involves the deployment of both bow and stern anchors. This type of mooring maintains the position of the vessel more effectively than the two points mooring. Four points mooring is generally used when carrying out soil boring activities and when working alongside the smaller jackets and vent stacks when: a) There is frequent need to pull in and out of the platform due to engineering/safety constraints e.g. venting. b) There is expected prolonged stay at a location.

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PTS 60.2405 OCTOBER 2012

c) Consistent heavy weather is expected. d) Soft mooring to the jacket/vent (structural engineer to be consulted and approval given). (2) Anchor handling assistance will be required when running four points mooring close to a jacket. (3) The main disadvantage for a work boat moored to four points is her dependence on an anchor handler. She will not be flexible to change her heading as in a two point mooring with an advantage change in weather direction.

5.8

DRILL SHIP OPERATIONS i)

Drill ship is vessel that has been fitted with drilling equipment. It is normally use to explore for oil and gas in deep water. The greatest advantages of this modern drill ships have are their ability to drill in water depth of more than 2500 meters and save time moving from one location to another.

ii) Modern drill ship was equipped with own propulsion and thruster system together with advanced dynamic positioning system that make it totally independent without having to rely on towing vessel for moving to another location and for the deployment of mooring system to stay at an location.

6.0

TOWING ARRANGEMENT AND OPERATION 6.1

TOWING ARRANGEMENTS 6.1.1

Towing Arrangement on Rigs and Barges

Towing arrangement on rigs and barges shall comply with the general requirements and Marine Warranty Surveyor (MWS) requirements. A typical towing arrangement shall consist of followings: i. ii. iii. iv.

v.

Two towing SMIT type brackets, one on each side on the bow. This type of bracket allows for a quick release in an emergency One chain bridle with each leg connected to the SMIT bracket by an open link. Each bridle leg is led througha closed towing fairlead at the extreme deck edge. The chain bridle meets at a triangular plate (Monkey face). The angle between the legs shall not exceed 60 degrees. A pennant wire complete with sockets (usually referred to as the Towing Pennant) connected to the other end of the triangular plate. This pennant shall be about 23 m or 75 feet in length. The end of the Towing Pennant will have a compatible size safety shackle. This shackle is for the purpose of connecting to the tug's towing wire.

The completed assembly shall be inspected and approved by PETRONAS appointed Marine Warranty Surveyors

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„SMIT‟TYPE TOWING BRACKET „SMIT‟TYPE FAIRLEAD RECOVERY W RE LEADING TO A WINCH TOWING PENNANT (75‟) 45 º TO 60 º TRIANGULAR PLATE (MONKEY FACE)

SAFETY SHACKLES

CHAIN BRIDLE

Figure 6.1 Towing Arrangement for rig / barges

6.1.2

Towing Arrangement on Tug

The typical towing line arrangement on the i.

ii.

iii. iv. v.

tug shall consist of, but not limited to:

A tow pennant of 23 meter in length. The size of the tow pennant should be equal or bigger than the main tow wire. The use of nylon stretcher is not allowed. A towing wire of 915 meter in length. The size of the wire shall be compatible with the vessel bollard pull, minimum breaking strength being 2 times the maximum static bollard pull of the vessel. Tow bar, gob-line, towing pillar or other arrangement to keep the towline in position and to prevent girding the tug. Suitable anti-chafe material to be fitted on sections of the wire where chafing is likely to occur. A complete spare set of the above equipment must be readily available on the vessel.

TRIANGULAR PLATE

TOW PENNANT (75)

MAIN TOW WIRE

SHACKLE RECOVERY WIRE

CHAIN BRIDLE

Figure 6.2 Towing Arrangement for AHT/AHTS

6.2

EMERGENCY TOWING ARRANGEMENTS

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1. In addition to the main towing arrangement, every rig or barge shall be fitted with an Emergency Towing Arrangement. 2. This emergency arrangement may be similar to the main towing arrangement or may consist of a single SMIT bracket/chafe chain/pennant system fitted at the same or other end. 3. For recovery, a pick up rope (10" x 150' buoyant synthetic rope) shall be connected to the towing pennant. At the end of this pick- up rope will be a pick-up buoy. 4. This emergency towing arrangement must be rigged and ready for use in any inter-field tow. It is for the purpose of keeping the barge/rig in a safe position while the main towline is being reconnected.

6.3

TOWLINE CATENARY 1. Towline catenary varies with the length of the tow wire, tug horse power/bollard pull, resistance of the tow, speed, and water depth and sea state. 2. A proper catenary is one of the most important controllable factors of the tow. An ideal catenary is able to minimize the shock loading imparted on the towline. Adequate vertical clearance from the seabed must be maintained to avoid damage to tow wire. 3. When the tug and the tow are influenced by wave action, considerably higher inertia occurs. Magnitudes of such loads increase as the towline stretches. The combinations of load and stretch result in energy absorption by the towing gear. Energy absorption and dissipation on the towing gear is a continuous cycle when towing in heavy seas. 4. A minimum length of towline is needed for directional control, to get the rig out of the tug's wake and to prevent the tug from being overrun by the rig/barge. The usual length of towline used for inter-field tow is between 610 meter and 760 meter.

6.4

PASSAGE PLANNING FOR TOWING 1. Passage planning has to be developed prior barge move taking into account the safest and economical route and that is approved and reviewed by Marine Coordinator or in some circumstances a third party warranty surveyor may present for insurance purposes. 2. The passage plan must indicate abort point, no go area and contingency plan for any emergency. The passage route shall be verified against the latest updated TOPO data 3. Before commencement of tow, all towing equipment and arrangement has to be inspected by third party surveyor and towing certificate issued.

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6.5

INTER – FIELD TOW For inter-field/in field tows, the barge / rig shall be towed from a fix bridle arrangement as described under Section 6;item 6.1.1 Towing Arrangement on Rigs and Barges..

6.6

TOWING WITH ANCHOR WIRES For short tows (less than 10 nautical miles and in good weather condition), a barge may be towed on the anchor wire. It should be noted that when towing on an anchor wire the 'dog' or 'pawl' on the wire drum must be engaged to ensure that the wire does not slip and to prevent damage to the winch. Anchor winch gear clutch must be disengaged.

6.7

DURING TOW PASSAGE 1. The responsibility of the tow shall rest with the tug master at point when last pennant wire or anchor wire is disconnected or in case only one AHT involved – when last anchor is retrieved and clear of the bottom at departure point, throughout the passage and until the time first anchor is dropped at final location. 2. The towing vessel shall advise the Marine Controller and Barge Master on the length of towing wire to be deployed or any alteration to that length as well as engine power settings at all stages. 3. During passage the tug master must continuously monitor the tow. The tug master is required to advise control room of all observed, anticipated or potential dangers to navigation and observed changes to meteorological conditions, unusual changes to barometric pressure etc. 4. These include but not limited to closing vessels shall be reported at agreed intervals on the course made good, speed and distance to go, as well as estimated time of arrival .There should be a constant exchange of information between the tug and tow on the weather forecast, dangers to navigation, changes to draft and trim likely to create a change in the towing characteristics and any deviation from the plan.

6.8

LOCATION APPROACH 1. Prior running out anchors, work permit shall be obtained from the OIM/CSR (as applicable) for the anchor job. 2. Although final approach to location has been agreed and approved in the anchor pattern the Marine Controller may deviate from the plan as when deemed necessary after considering changes in the effect of environmental factor such as prevailing weather and current and any other factor from that

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have been anticipated in the plan. Each deviation shall be discussed and agreed with Marine Coordinator prior to execution. 3. When making approach to site the general rule is to stem the wind and current or whichever is dominant. This is to allow the Tow/AHT vessel to maintain barge / rig position when first anchor is deployed and brake is applied.

6.9

SAFETY REQUIREMENTS 1. In determining safe towing operation the following shall be observed: i. ii. iii. iv. v. vi. vii.

Three days (72 hours) weather forecasts will be made available prior commencement of operation. All openings on weather deck are to be closed and secured. All equipment on deck and loose item to be secured or lashed. Barge to have sufficient stability, bearing in mind lost of Gravity Metacentre (GM) due to free surface effect of slack tanks. Light and shape as outlined in the International Collision Regulation (COLREGS). Sea fastening and barge / rig towing equipment must be checked at frequent intervals during passage. A spare towline satisfying all the requirements of the main tow line should be kept onboard and readily available.

2. In the event of encountering heavy weather during passage the following shall be considered: i. ii. iii. iv. v.

7.0

Increase the tow line catenary to minimize shock load. Alteration of course and /or speed to minimize the effect of sea and swell. Pressing up slack tanks to increase stability. Keep shore informed of deteriorating conditions. Seek shelter.

MOORING EQUIPMENT 7.1

ANCHOR MOORING ARRANGEMENT 1. Rigs / barges / work boats in offshore locations are moored by anchors to maintain their position. 2. These anchors are laid in an 'Anchor Pattern' designed to suit the barge /workboat / rig. However in some circumstances deviations from the approved anchor pattern is required owing to pipeline and/or other obstructions. 3. For jack-up rigs, anchors are used for positioning the rig, pulling her off a jacket or maintaining her position while retrieving legs in a restricted area. 4. Specifications of the anchor mooring equipment vary with the type of rig or barge. Invariably the equipment should be classed by a reputable

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Classification Society i.e. International Association of Classification Society (IACS).

7.2

WINCHES / WINDLASS 1. Winches are machinery used for hauling in and paying out anchor cables. 2. The winch is the heart of a mooring system and should always be kept in good running condition. 3. Winches may be fitted with a single or double drum, the former being preferred as it allows for greater flexibility in anchor handling operations. An independent internal combustion engine, hydraulic or electrical power, may drive them. 4. Electrical powered winches with torque control are preferable. These winches can be run at a controlled variable speed, enabling anchors to run under tension when required. 5. An important part of the winch is the brake. Winch brakes should be set to hold to a load of about 60% of the Minimum Breaking Load of the wire above which slippage can occur. 6. Oil, moisture or heavy rust on brake linings should be avoided as they can reduce holding power of the break. 7. When running out anchors (with AHT assistance) the gear shall not be engaged and avoid excessive winch speed as this can also reduce brakeholding capacity by the build-up of heat in the lining.

7.3

CLOSED CIRCUIT TELEVISION MONITORS (CCTV) When operating an anchor winch, the operator must have a full view of the winch drum via CCTV.

7.4

TENSION METERS 1. Tension meters shall be fitted for the purpose of pre-tensioning anchors and monitoring anchor wire tensions. It is important that the Rig Mover / Marine Controller / Barge Master to constantly monitor the tension on all anchor wires when running anchors. 2. After a barge / workboat / rig is in position, anchor wire tension has to be monitored continuously for the following purposes: i.

Maintaining appropriate tension to avoid chafing of pipelines or keeping vertical clearance from anchor wires of other barges at same location or during simultaneous operations.

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ii. iii.

In heavy weather, tension on the anchor wire is one criterion in deciding to stop work and pull off. Anchor wire tension may be recorded continuously on a graph to monitor the strain / load on the wire. This information may be useful in ascertaining the life of the wire.

3. Tension meters shall be calibrated yearly to ensure a correct reading at all times.

7.5

FOOTAGE COUNTERS i)

Footage counters indicate the length of wire paid out from the fairlead. This instrument will also come in useful when marking wires for whatever purposes including marking of spring buoy position.

ii) Footage counters shall be calibrated yearly to ensure correct reading at all time

7.6

FAIRLEADS AND ROLLERS 1. From the winch drum anchor wires are usually led through a series of rollers before reaching the roller fairlead. 2. The diameters of these rollers must be compatible with that of the wires. The moving parts must be regularly checked for wear and tear.

7.7

ANCHOR CABLES Anchor cables may be wires, chains or wire/chain combinations. Anchor wires offer greater flexibility in anchor handling operations especially in pipeline areas and shallow waters. It is recommended to use only Regular or Ordinary Lay wires with Independent Wire Rope Core (IWRC). Wires should be galvanized. Length and size of wires vary with the type and size of the rig/barge, the minimum length being 915 meter. Pipe-lay barges, installation barges, semi-submersible rigs, drill-ships and vessels with self-anchor laying capability usually have longer wires. The anchor end of the wire shall be fitted with a closed type Spelter Socket or Gold Nose socket. Experience has shown that this type of socket is more robust, easier to handle and can be replaced onboard the barge. It is also specified for the purpose of standardizing anchor handling equipment. The use of bulldog grips for making terminations is not acceptable. The drum end of the anchor wire shall be connected in such a manner that it can be released easily in an emergency.

to

the

drum

Chains and wire/chain combinations are not commonly used except in semisubmersible rigs and drill-ships. Chains used shall be of Oil Rig quality. In

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wire/chain combinations a length of chain is fitted to the wire just before the anchor. This chain serves as part of the ground cable and it enhances the holding power of the anchor.

7.8

ANCHORS A wide variety of anchors are used in mooring rigs and barges offshore. An ideal anchor shall have the following characteristics: i. ii. iii. iv. v. vi. vii.

High holding power in varying soil conditions. Possess good stability in its buried position and when it is dragged through the seabed when tensioning. Capability to quickly engage and penetrate the seabed upon dropping. Have a low breaking out force. Lightweight and easy to handle. Not prone to being damaged or causing damage to anchor handling vessels. Must have no moving parts, which may be clogged or jammed in operation. Anchors fitted on the barge/rig must be of the type and size mentioned in the specifications.

The 'FLIPPER DELTA' type is most commonly used in our operations. They have been found to be efficient and reliable, and therefore highly recommended. High holding power anchors e.g. Stevpris and Bruce anchors are acceptable. All anchors must be fitted with a chain pigtail (about 4 meter long) at the crown end. This is to provide for safer handling and avoid chafing of pennant wire, which commonly occurs if they are fitted directly to the anchor. Some anchors, e.g. FLIPPER DELTA and STEVIN, have a provision for changing fluke angles to suit the soil conditions. This provision shall be made use where necessary.

7.8.1

Piggy – Back Anchor A back-up anchor, which is connected to and laid in line with the main anchor, is referred to as a piggyback anchor. The distance between the main and the piggyback anchor is determined by the pennant wire length (water depth + 25metres) but should not be less than 45metres. To effectively lay a piggyback anchor, the intermediate pennant must be well stretched and the anchor must be laid in the same direction as the main anchor. Piggyback anchors may be required under one or a combination of the following circumstances. i. ii.

Where the seabed condition offers poor anchor holding ground. Where prerequisites tension cannot be achieved within a reasonable time.

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iii.

Where there is insufficient ground wire owing to limited anchor wire length or anchor pattern being restricted by pipelines or structures Since lying of piggyback anchors is time consuming and requires additional equipment, the practice should be discouraged and carried out only as a last resort. The use of high efficiency anchors, like the 'Flipper Delta', will minimize the need for piggybacks. Despite their high initial cost, experience has shown that these high efficiency anchors are beneficial on the long run. When preparing for a rig or barge move, the need for piggyback anchors shall be considered so that prior arrangements can be made to acquire and transport the additional anchors and fittings to the location. In laying piggyback anchors the requirements for anchoring in pipeline areas shall be complied with.

Figure 7.1 Piggy Back Anchor 7.9

PENNANT WIRES Pennants wires are used for laying and retrieving the anchor. Pennant wire used shall be similar in size and type to the anchor wires. Occasionally where the anchor wire is small (e.g. 1-1/4 inch) then a slightly bigger pennant wire (e.g. 1-1/2 inch) may be used. This is because the wear on the pennant is usually greater than that of the anchor wire. If the anchor digs down deeply into the seabed, it is recommended to use bigger pennant wires to avoid losing the deeply penetrated anchor. The length of the pennant wire varies with water depth, expected anchor penetration, tide and sea conditions, and type of anchor handling tug. As a practice pennant length for crucifix type buoy shall be water depth + 15 meter for hard sea bed and water depth + 30 meter for soft mud conditions. Pennant wire arrangement depends on the type of anchor buoy. For a suitcase type buoys the pennant consist of a single length of wire. The main disadvantage of this

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system is the need to constantly change out the pennants to suit the locality. For a crucifix type buoy the pennant may consist of a combination of different lengths. Then it is only a matter of putting together the correct length with minimum joints. Pennant ends shall be fitted with Gold Nose wire termination. For the suitcase buoy arrangement, the buoy end may be spliced. In order to avoid excessive load at this end, sufficient turns should be taken up on the work drum of the anchor handling tug before lifting the anchor. When a barge/rig is on tow it is important that the pennants are properly hung off or stowed.

7.10

ANCHOR BUOYS Anchor buoys serve to hold the pennant wire and as a marker for the anchor position. They come in varying shapes and sizes. An ideal anchor buoy shall have the following characteristics: 1)

2) 3) 4) 5) 6) 7)

8)

Required Buoyancy - this is directly related to the weight of the pennant. There should be sufficient reserve buoyancy to ensure that the buoy is always visible above the water. A good balance to keep the buoy upright. Consist of several compartments. Foam filled. Have rounded corners with minimal sharp edges. Have flat sides for better stability when placed on anchor handler deck. Connected to anchor by pennant wire of suitable size and length. The length of pennant wire should be equivalent to the water depth plus maximum of 20m. Be painted with highly visible and luminous colour.

7.10.1 Crucifix Type Buoy This type of buoy is used commonly on rigs and maintenance barges. The advantages of this system are: No need for a complete change out of pennant in varying water depths. Piggyback anchors can be laid without having to change the pennant system. No chafing of pennant with the buoy as in the case of the suitcase type buoys. Convenient for bringing anchor on the anchor handler deck.

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Figure 7.2 Crucifix Buoy

7.10.2 Suitcase Type Buoy This type of buoy is commonly used on installation, pipe-lay and construction barges, which move frequently. With this type of buoy, anchor-handling operation is much faster and work on the anchor handler tug is minimized. However it lacks the advantages of the crucifix type buoy. Another disadvantage of this system is that most of the joints and fittings remain underwater during anchor handling. It is therefore important that the whole anchor / pennant / buoy system be lifted on the barge for inspection regularly

Figure 7.3 Suitcase Buoy

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7.11

SPRING BUOY Spring Buoys are buoys that are connected to anchor wires for the purpose of giving the latter a vertical lift. They are used when there is insufficient vertical clearance between pipelines and anchor wires crossing them

Figure 7.4 Spring Buoy

7.12

BUOY CATCHER Buoy catchers are used to retrieve anchor pennant buoys. The buoy catcher sling is attached to a tugger winch on deck to enable it to pull the buoy clear of the water. The recommended assembly for the buoy catcher sling should consist of the following: 1. One x 2 feet x 1/2 inch diameter chain 2. Two x 20 feet x 3 inch circumference wire 3. One connecting ring All buoy catcher slings shall be colour coded in accordance with the Company's procedure for the registration, inspection and maintenance of slings and lifting tackle.

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Figure 7.5 Buoy Catcher

7.13

OTHER FITTINGS The various connections between wires, chain, pennants and buoys shall have a compatible Safe Working Load (SWL) with the items they connect. Suitably sized shackles / Baldt links should be used to ensure slightly loose fitting for ease of connecting and disconnecting. Drilling tenders and work barges, which remain in position for a period of more than 6 months, shall use Baldt links for connections. Proper split pins shall be used and sufficient spares are made available during anchor handling operations. Shackles must be Safety Type Shackles i.e. with hexagon head pin, nut and split pin.

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Figure 7.6 Baldt Link and Safety Shackles

8.0

ANCHOR PATTERN 8.1

DRAWING OF ANCHOR PATTERN In drawing anchor patterns, the following procedures shall apply: i.

Draw on an updated 1:5,000 scale survey chart. The 1:10,000 scale charts shall only be used if the 1:5,000 scale charts is not available for the field. If other barges are in the field, or are expected to be in the field, then the chart used shall show their anchor patterns. The PETRONAS project owner shall ensure that correct charts are given to the contractors. These charts are to be obtained from PETRONAS through Marine Coordinator and relevant parties for International operations

ii. iii.

Draw to the correct scale. Show the barge, the anchor position with their numbers, direction and distance from the barge. Additionally distance from obstruction and/or pipelines. Where anchor cable/s cross pipeline/s, show the touchdown TENSION (kips) at the crossing and the touchdown POINT at 9.1 MT (20kips) and 27.3 MT (60 kips) respectively. (2.2 kips = 1 MT)

iv.

8.2

FACTORS TO CONSIDER FOR ANCHOR PATTERN i. ii. iii. iv.

Keep the pattern symmetrical to maintain even load distributions Scope of work of the barge Barge position - it is recommended to keep to leeward side of the platform, head into predominant swell and/or weather, and crane reach. Amount of cable required - depends on water depth, nature of the bottom of the site.

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v. vi. vii. viii. ix. x. xi. xii.

8.3

Gangway positions and access to the platforms. Expected weather, tide and current. Time of move and duration of stay. Helicopter access. Presence of other barges in vicinity. Minimal use of soft moorings. Supply vessel and crew boat access. Comply with the anchoring restrictions requirements specified in Section 9, paragraph 1.

ANCHOR PATTERN APPROVAL All vessels that are required to anchor within the vicinity of platform, pipeline or installation shall seek anchor pattern approval from PETRONAS Marine Coordinator or any other assigned person prior to carrying out anchor deployment. 8.3.1

Early Submission of Request All anchor patterns request shall be submitted well (minimum 14 days prior to mobilisation) in advance to PETRONAS Marine Coordinator to avoid any delays in approval.

8.3.2

Supporting Document Request shall be submitted with the following supporting documents: i. ii. iii. iv. v. vi. vii. viii. ix. x. xi.

Approach to Location Sequence of anchoring Anchor touchdown catenaries Anchor wire size/tension Spring buoy location (parachute/Damage protection buoy) Type of anchor/weight Anchor handling boats Brake Horse Power (BHP) Working winch capacity/Date last tested Type of seabed Mooring procedures Contingency Plan/Emergency Pull Out due to a. Adverse Weather b. Emergency situation on platform

9.0

ANCHOR HANDLING OPERATIONS 9.1

ANCHORING RESTRICTION 1. Positioning of anchor shall conform to the following mandatory distances requirements. 2. Minimum distances shall be met after allowing the anchor to set in until it reach the ultimate holding capacity or after pre tensioning of anchor has been performed.

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3. If it is necessary to run an anchor wire over a pipeline/under water telecommunications cables, the anchor wire catenary calculation should be consulted and appropriate anchor support i.e. parachute buoy to be used. 4. In preserving the environment, coral communities shall be avoided. In scattered coral area the following mandatory distance requirement shall also be followed 9.1.1

Anchor Position Crossing Pipeline i. ii.

Distance between anchor and closest pipeline not less than 150m (figure 9.1) Distance along anchor wire from crossing point of closest pipeline to anchor not less than 220m. ( figure 9.1)

Figure 9.1 Anchor Crossing Pipeline

9.1.2

Anchor Position between Barge and Pipeline i. ii.

Distant between anchor and closest pipeline not less than 100m (figure 8.2) If water depth more than 100m the distance is equal to depth of the water.

Figure 9.2 Anchor position between barge and pipeline

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9.1.3

Anchor Wire Parallel to Pipeline Distant between anchor and pipeline not less than 150 m (figure 8.2)

9.1.4

Anchor Positioning in the Vicinity of Structures i.

ii.

When anchors are positioned in the vicinity of existing marine structures, a minimum of 150m horizontal clearance from the structures shall be maintained. (figure 9.3) A minimum of 5m shall be provided between anchor wires and any part of a platform or associated structures at all times.

Figure 9.3 Clearances from Structures

9.1.5

Anchor Wires Crossing Existing Pipelines i.

Anchor wires crossing pipelines within the elevated section of the catenary shall at all times maintain a vertical clearance of not less than 5m ( figure 9.4)

Figure 9.4 Vertical Clearances from Pipeline

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In the event above requirements cannot be achieved, clarification and approval shall be obtained from the marine Coordinator 9.2

ORIENTATION OF ANCHORS 1. The barge shall be equipped with a minimum number of eight anchors. (During operation, the number of anchor to be deployed shall be subjected to anchor pattern approval). 2. For a self propel vessels that are able to maneuver to avoid endangering the structure in the event of a drift or emergency, a four points mooring is sufficient (including soft moor). 3. The orientation of the anchors relative to barge during operation is determined using the following: a) The bow anchors provide the main forward pull during barge advances. They will be positioned forward and slightly out from the barge route. b) The bow breast anchors are for lateral control and for forward pull during barge advances. They will be positioned somewhat further out from the bow anchor. c) The stern breast anchors are for lateral control of barge stern. They will be positioned only slightly forward from the barge stern. d) The stern anchors are positioned to bring the barge to a stop forward movement. The orientation of all anchors will be such that adequate back up is provided during anchor relocation.

9.3

CONTINGENCY PROCEDURES Contingency procedures for every foreseeable anchoring difficulty shall be included as part of the anchoring procedure; 1. For retrieval of anchor when anchor wire has parted. 2. For retrieval of anchor when pennant wire has parted/entanglement. 3. For retrieval of drifting (runaway) pennant buoy. 4. To ensure safe mooring of vessel in bad weather. 5. In the event of anchor (s) drags. 6. For escape in the event of emergency. The barge shall be able to

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clear the location of the platform independently. 9.4

EXTENDED HOURS ANCHORING OPERATIONS 1. Ideally anchoring operations is carried out during daylight with 1 set of crew. However it can also be carried out in 24 hrs operation if 2 sets of independent crew are available on board the barge and AHT. 2. For the case of 1 shift crew it is allowed to work a maximum of 16 hrs to avoid fatigue issues. CSR to conduct risk assessment which includes adequacy of lighting and safety of the crew. 3. Should anchoring in non-daylight hours be necessary, the following additional requirements shall apply

The Barge and AHT to be equipped with Barge Management System (BMS), where location of all pipelines is charted and the location of Barge and AHT in relation to the existing pipelines are continuously shown. Anchor handling operation outside 1000m from coordinate of anchor position to the structures/pipelines does not require BMS Pennant buoys used are large enough to act as radar reflections. The anchor buoys are continually monitored in reference to the marker buoys or Barge Management System. 9.5

ADVERSE / MARGINAL WEATHER PRECAUTIONS 1. Mooring / anchoring during bad weather is NOT PERMITTED, especially in areas within the vicinity of existing pipelines and platforms. As a guide, weather is considered bad when significant sea / swell is more than 2.5 meters or wind speed is more than 25 knots (This criteria may differ according to different locations where local requirements shall apply) 2. The criteria generally used for determining limiting conditions are the maximum tension allowable in the anchor wires. The rig/barge shall only remain alongside an installation, whilst all the anchor wire tensions are within the acceptable working range. 3. During initial setting up at new location, barges are required to carry out tensioning of anchors. Anchors are pretension in excess of their normal working tensions, to allow for expected environmental loads on the mooring system. When anchor wire tensions begin to approach these pre-tension values, the barge should be in the state of readiness to ensure that she is able to suspend operations and pull out in minimum time required, if the weather continues to deteriorate further. 4. The barge may also pull out of location when the sea conditions begin to limit the type of work operations being carried out, although her sea keeping qualities might not be adversely affected. 5. The Barge Master shall continuously monitor all weather forecasts; sea

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state conditions and anchor wire tensions, so that he is able to take prompt action as soon as limiting weather conditions are being approached. 6. Every rig/barge shall have their limiting operating conditions clearly stated in their Operation Manuals. The various stages of „Alert‟ and „Required Action‟ shall also be clear.

9.6

TRANSFERRING ANCHOR FOR RUNNING All works involving decking/ lowering and connection/ disconnection of anchor from the AHT, AHT vice versa Barge/ work boat/ rig must be carried out at least 100m from pipelines or subsea installation. i.

Crucifix Type Buoy If the anchor is detached to the anchor wire: 1) 2)

3) 4)

5) 6)

The anchor, its pennant wire (secondary and primary) and the buoy are transferred to the AHT by barge crane. Connect secondary pennant wire (length depending on water depth) to the work wire and spool it into the drum. The last set being the primary pennant which will be connected to the anchor at the chain pigtail. Once connected take up the slack on the pennant. The barge then will pass the end of anchor wire and the AHT will pick up by means of tugger wire and align and secure its socket at the shark jaws. Connect the anchor to anchor cable. The AHT takes the anchor on its deck or secure it against the stern roller for running.

If the anchor attached to the anchor wire: 1) 2) 3) 4)

5) 6) 7)

ii.

The secondary anchor pennant wire (length depending on water depth) and the buoy is transferred to the AHT barge crane. Connect the secondary pennant wire to the work wire and spool them into the drum. The barge then will pass the primary pennant wire either by barge crane or AHT tugger wire. Align the primary pennant wire at the shark jaws and secure it at socket. The secondary pennant wire can now be connected to the primary pennant wire. The barge will slack away the anchor cable gradually. The AHT/AHTS takes the weight of the anchor. The AHT/AHTS takes the anchor on its deck or secure it against the stern roller for running.

Suitcase Type Buoy 1. The buoy is transferred to AHT/AHTS by using barge crane. 2. The buoy then lowered next to the AHT stern roller. AHT deck crew pick

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up the end of the pennant wire and connect it to the work wire. 3. The barge slack away the anchor wire gradually while the AHT crew spool in the pennant wire and takes the weight of the anchor. 4. The AHT takes the anchor on its deck or secure it against the stern roller for running.

Figure 9.5 Transferring Anchor for Running

9.7

RUNNING ANCHOR 1. The AHT will proceed to approved anchor coordinate while maintaining slight tension on the anchor wire so as to ensure no bight is formed on the anchor wire. This is also to ensure the belly of the anchor wire is not being dragged on the seabed especially when subsea facilities are present. 2. Barge should constantly check on the wire tension by means of remote winch tension meter and advise AHT accordingly. 3. Position of the barge is monitored using survey management system i.e. BMS. Anchor foreman instruct AHT to adjust her course and speed if needed. 4. Once bottom is clear of pipeline or cable the anchor is held below stern roller for dropping. At about one ship‟s length to location, the AHT will reduce her speed. Once the AHT is on target, barge will apply brake on the winch and the AHT will commence lowering the anchor to seabed. 5. When lowering anchor, the AHT will maintain her forward movement. This is to ensure light tension on the pennant wire as well as the anchor wire. Kinks and fouling of wires to the anchor can be prevented. 6. The AHT will continue paying out the pennant wire. Once the anchor is on the bottom there should be no headway and the pennant wire is straight up and down, the position is then recorded. 7. Recheck the position of the anchor and if everything is satisfactory cast off the buoy into the water. 8. When the anchor hoist operator is satisfied that the anchor is firmly set in the seabed, the tension of the anchor wire is gradually increased to its working tension. He is also to confirm that the anchor is holding before sending the AHT to her next task. 9. The amount of anchor wire paid out and the horizontal distance from fairlead derived from survey positioning equipment is then recorded. A comparison of these distances will be used to determine any anchor slippage. 10. At least one layer of anchor wire must remain on the winch drum.

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11. After all anchors are set and before moving the barge to its working position, the anchor should be pre-tension. If the anchor drags, redeploy and test the holding capacity. When working adjacent to platform tension on the anchor wire shall not exceed this tested tension.

Figure 9.6 Running of Anchor i.

Running Anchor under Platform Bridge There are times where anchor is required to run under the bridge especially in congested area in order to maintain even spread of anchor holding the barge. Should it be necessary to run anchor under bridge the following method shall be used: No Subsea Installation in Vicinity and Away from Jacket Leg 1) 2) 3)

The AHT run the anchor as usual and drop the anchor immediately under the bridge together with the buoy. The AHT will proceed to the other side of the bridge and retrieve the buoy and anchor. The anchor is then run to its intended position.

Subsea Installation Vicinity and Close to Jacket Leg 1) Transfer the anchor, anchor buoy and its pennant wire to the AHT. The pennant wire is spooled into the winch. 2) The AHT will proceed to the other side of the bridge. 3) A small line handling vessel is employed to run a polypropylene messenger rope connected to the anchor wire. 4) This messenger rope is passed to the AHT to pick up the anchor wire. Alternatively, if second AHT is available the anchor wire is towed close to the bridge and a pass the anchor wire to the other side of AHT by means of messenger rope. 5) The anchor wire is now connected to the anchor and run to its intended position. ii.

Static Running of Anchors In cases where it is not possible to maintain the required minimum

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vertical clearance from subsea obstruction in shallow water, despite running wires under tension. In such situations, the anchor wire shall be run static as follows: 1) The anchor buoy and pennant wire is transferred to the anchor handler. The anchor is located on the deck of AHT and disconnected from the anchor wire. Sufficient length of anchor wire is spooled onto the work drum to reach the target location. 2) AHT pays out the anchor wire as she proceeds towards the anchor location. 3) Once the vessel on location, the anchor is connected to anchor wire and gradually lowered to the seabed with little headway on the AHT. 9.8

DECKING OF ANCHOR 1) Anchor shall always be decked, before running across pipeline(s). When an anchor is brought on deck, it should be placed forward of the anchor handling tong/jaws with the anchor wire locked in. However, the weight should be taken by the work wire and not by the tong/jaws. 2) It must be appreciated that with the anchor on deck, when running anchors, the catenary of the anchor wire is lesser than when the anchor hangs below the stern roller. While this helps to elevate the base of the catenary, it also reduces the shock absorbing effect of a good catenary. It also reduces the maneuverability of the vessel. Special caution must be taken to avoid any shock load while running the anchor.

Figure 9.7 Decking of Anchor

9.9

CASTING OF BUOY i.

Crucifix Type Buoy 1) Raise the shark jaws and slack away the pennant wire until the socket on the last set of pennant wire rest on it. 2) Connect the buoy chain pigtail to the end of pennant wire. 3) A slip hook is connected to the work wire is then attached to pennant wire. 4) Take the weight on the work wire and lower the shark jaws.

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5) Pay out on the work wire until the slip hook and the buoy is released. If Triplex shark jaws are used, omit step 3 to 5. Maneuver the vessel to slack away pennant wire then lower the shark jaws to release the buoy. ii.

Suitcase Type Buoy 1) A slip hook connected to the work wire is attached to the pennant wire. 2) Pay out pennant wire until the end is at the stern. Connect the tripping wire to the slip hook. 3) Continue pay out the work wire, as the tension on the tripping wire will release the end of pennant wire from slip hook.

Figure 9.8 Casting of Pennant Wire of Suitcase Buoy using Slip Hook

9.10

SOFT MOORING TO JACKET LEG 1)The need may arise to make fast one or more line to jacket leg to hold the barge. This is because it is impractical to deploy the anchor especially in congested areas. 2)All soft moorings to jacket legs have to be incorporated in the anchor pattern and approved by PETRONAS Marine Coordinator. Prior approval the following criteria shall be met. a) Number of soft mooring is determined by maximum mooring load the platform can take. b) Verify that the load is within acceptable limit. c) The soft mooring must consist of a weak link where the breaking strength must not exceed 75% of the allowable structure strength of the facilities. d) Under no circumstances a wire rope is loop directly around jacket leg as it will chafe thus damage the leg and the wire also may also come apart. e) Means should be provided to secure the line in a figure of eight configuration to allow for fast retrieval during emergency and for tending the line during rising and falling tide. f) Sequence of retrieval during emergency pull out must be addressed to all

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concerned parties. g) Job Hazard Analysis must be provided involving all personnel engaged in the operation. h) Approval by structural engineer and OIM. 9.10.1 Deployment of Soft Mooring For deployment of soft mooring to jacket leg, the following procedure shall be used; 1)

2) 3)

4) 5)

9.11

Upon setting up sufficient number of anchors, the barge shall detach the anchor, buoy and pennant wire from the anchor wire intended to be used. Move the barge closer to the platform by means of heaving up and slacking the anchor wires. The derrick crane will pick up the end of anchor wire complete with soft mooring arrangement. Alternatively a stand by boat could be used to transfer the line. The soft mooring is loop around the accessible jacket leg by personnel stationed on the platform. Tension not exceeding allowable load will slowly be applied to the soft mooring line.

PRE – TENSIONING OF ANCHOR 1) Line pre tensioning should be done after setting all anchors. Anchors are pre-tension in excess of their normal working tension to allow for environmental load on the mooring system. 2) Working tension varies with the type of barge. In general, upon deploying anchor tension of 6.8 to 9.1 MT (15 to 20 kips) to be applied to ensure the anchor digs in. 3) When all anchors are deployed the tension of each wire is increased to 13.6 MT (30 kips) diametrically opposite anchor. 4) Monitor the tension meter and the amount of wire reeled in. Steady meter reading on a particular test tension indicate that the anchor is holding. 5) The tension is further increased to 18.2 MT (40kips) or 50% in excess of their working tension whichever is greater. 6) After reaching minimum test tension, each wire is reduced to its normal working tension. 7) In area where bad holding ground is anticipate, the process is the same except that the anchor must be allowed to soak in at various stages of tensioning. It requires close monitoring which duration varies between 30 min to 6 hours depending on the seabed condition. The anchor needs to be redeployed if there is indication that it is dragging

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8) After redeployment and the anchor is still dragging use of piggy back anchor should be considered. 9.12

ANCHOR RETRIEVAL PROCEDURE i.

Recovery Pennant Buoy (Suitcase Buoy) 1) 2) 3) 4)

ii.

The AHT proceeds to designated anchor buoy. AHT will back up to buoy and the deck crew will pick-up pennant wire. The pennant wire is finally connected to the work winch Heave up on the work winch until anchor on-board the AHT deck.

Recovery Pennant Buoy (Crucifix Buoy) 1) 2) 3) 4)

5)

AHT proceeds to designated anchor buoy. AHT will back up to buoy and the deck crew will pick-up buoy by means of buoy catcher connected to tugger wire. Once the buoy is on deck the guide pin is raised to centralize the pennant wire. Keep heaving until pennant socket is slightly forward of shark jaws/kamforks. Engage the shark jaws/kamforks then slack off tugger wire to secure the pennant socket at the shark jaws/kamforks. Disconnect the buoy from pennant and connect the work wire to it. The anchor is now ready to break out.

Figure 9.9 Retrieving Crucifix Anchor Buoy

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iii.

Use of Anchor Chaser

(1) There are few alternatives employed to retrieve anchor without pennant line in the event the pennant line parted. a) The barge may self pick the anchor by moving it in the direction of the anchor. b) By passing the anchor wire to the AHT, connect it to the work wire and recover the anchor. (This technique is tedious and time consuming) (2) The most common method is by stripping out the anchor wire by means of a suitable chaser. However care should be taken as this method imposes very much higher strains on chaser pennant wire as well as on the work wire. When this method is employed, the following procedure shall be adhered to. a) Take careful note current set and wind direction which might set the AHT off the anchor wire when stripping. b) Pre-calculate the amount of wire needed for that water depth to achieve correct chaser pennant wire length of one half or twice the water depth. c) Predetermined type of sea bottom and whether the anchor has achieved full tension test. d) The barge is moved away from the platform, hold in position by compensating tension on other anchor wires. e) Slack away the anchor wire, a section of the wire is placed on the AHT deck and slips the chaser into the anchor wire. f) The chaser assembly (chaser and pennant wire connected to the work wire) takes the weight of the anchor wire before releasing the section of wire. g) Slack away the work wire to lower the chaser into the water and align the AHT along the anchor wire bow towards the anchor. h) The barge will pick up tension gradually on the anchor wire to a limit below than that of the test tension. i) Commence stripping out the anchor wire and give particular attention on the strain of the pennant wire. (Strain increases as the chaser closes to the anchor). j) Before breaking out anchor, chaser tug will attempt to slip the chaser into the anchor shank and position itself based on the prevailing weather and availability of nearby facilities k) Chaser tug breaks out the anchor by applying tension on the work wire and if necessary use main engine to give required force. A sudden slack on the anchor wire is an indication the anchor breaks out from seabed. l) Slack on the anchor wire slightly and lift the anchor up.

9.13

PERMANENT CHAIN

CHASER (PCC) SYSTEM

PCC is the other method used to deploy and retrieve the anchor. The use of this system of deploying and retrieving anchors imposes very much higher strains on the pennants and work wires than normal

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buoyed systems.

Figure 9.10 Example of Chain Chaser i.

Preparation for Running Anchor 1) 2) 3)

Barge / rig crane lowers pennant wire. Vessel crew attaches tugger wire to lazy strop. Crane wire shall slack off so that pennant wire end is below stern roller. Connect the pennant wire to the work wire and spool them into the drum until the anchor has been hoved up hard against the roller.

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Figure 9.11 Preparations for Running Anchor (PCC System) ii.

Running the Anchor Running of anchor are similar to item 6 of this section.

Figure 9.12 Running of Anchor (PCC System)

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iii.

Stripping of Chaser and Passing Pennant Back to the Barge / Rig 1) 2)

3) 4) 5)

i. ii. iii.

6) 7) 8)

Once confirmed that the anchor is holding, the chaser shall be stripped off and send back to the barge / rig. Work wire shall be shortened up to 1.5 time water depth and the AHT/AHTS turned around through 180º and exactly back over line of the chain. Work wire shall be kept under very low tension during this manouevre. Chaser is now pulled off from the anchor and towed back to the barge / rig. The chaser can be felt when it‟s clear the anchor by the following: A steady very low tension on work wire. A steady tension on anchor lines. When chaser is on the chain and moving freely the work wire will „jump‟ in rhythmic motion as the chaser is towed along. The winch operator on the barge / rig may feel the chaser moving on the chain. When approaching the barge / rig, the vessel shall be to 180º when about 3 vessel length. Commence shortening of work wire and the vessel continue coming astern in line with the anchor cable. Move the vessel sideways clear of the anchor cable towards the pennant pick up position under the crane.

Figure 9.13 Stripping of Chaser (PCC System)

iv.

Retrieving / Breaking Anchor (PCC System) 1) 2)

Take chaser pennant on deck and connect to work wire. The vessel move off from the barge / rig in line with the anchor wire. As the vessel approaches the distance calculated chain

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3) 4)

length from barge to anchor, water depth, work wire length, be ready to ease down on the power. Work wire will stop twitching when anchor is reached and the chaser comes onto anchor. Shorten in the work wire to 1.5 times water depth and keep steaming slow ahead while barge / rig is slacking off tension on the anchor cable (15 m). Upon slacking of the cable to 15 m, increase engine power to half way ahead. When the tension drops the anchor is out of the ground.

Figure 9.14 Retrieving Anchor (PCC System)

10.0

SAFE WINCH OPERATIONS (a) HSE is the most important element in any winch operation. The winch operator shall always take the necessary safety precautions required to prevent injury to him or to others. (b) Tabulated below is a list of the most common safe operation practices. Specific work situations may require additional precautions. 1) 2) 3) 4) 5)

6) 7) 8) 9) 10) 11) 12)

Read and understand the winch operation manual before attempting to operate the unit. Only trained (attended the rigging and slinging course) and experienced persons should be allowed to operate a winch. Do not use the winch for hoisting or lowering people. During operation, concentrate on using correct procedures. Stay clear of wire ropes during operation (barricade). Do not operate the winch if there are people are near wire ropes, winch drums, level-winders (Spoolers) or other moving parts. Never leave the winch unattended when the drive motor is running. Never climb onto the winch when the motor is running. Inspect wire ropes and attachments before operating. Replace any damaged wire rope or attachments before operating the winches as per standard industry practice. Wear appropriate protective equipment during both operation and maintenance. Use only the specified diameter wire rope. Do not exceed winch load rating. Exceeding the load rating can damage the winch and

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13) 14) 15) 16) 17)

18)

19) 20) 21) 22)

11.0

cause accidents. Do not exceed rated line speeds. This can also damage the winch and cause accidents. Avoid excess side loading. Always leave a minimum of one full layer of wire rope on the drum. Clean greasy or slippery deck around the winch. Never operate with winch guards removed. All guards must be securely fastened before operating. Make this the final step in winch maintenance along with removal of all tools and / or test equipment. Never use the drum pawl to stop winch drum rotation. Such practice will create sudden shock loads on the wire rope and winch drive, and it could severely damage the winch or break the wire. Always stop the winch drive motor for any lubrication work. Maintain regular and systematic inspection of the winch. Maintain regular and systematic winch lubrication. Maintain communication during all winch operations. Always maintain back-up communications. Instructions should be clearly understood and repeated before an operation is carried out.

SAFE OPERATIONS Procedures shall be developed and implemented for the following CRITICAL activities, but not limited to: 11.1

11.2 11.3 11.4 11.5

11.6 11.7 11.8 11.9 11.10 11.11 11.12 11.13 11.14 11.15 11.16 11.17 11.18 11.19 11.20 11.21 11.22 11.23 11.24

Anchor handling and positioning – anchoring restrictions, stability, orientation of anchors, contingency procedures, extended hours operations, transferring anchor for running, running anchor, decking of anchor, casting of buoy, retrieving anchor, winching Lifting – Lifting plan, critical lifts, competent operator/rigger/signal man Securing cargoes on deck – Cargo securing manual Mooring – crew safety, mooring equipment, tug operations, mooring analysis Towing – towing arrangements, emergencies towing arrangements, towline catenary, passage planning, inter field tow, towing with anchor wires, during tow passage, location approach, tugboat operator competency Boat transfer – types of personnel transfer, duties of key personnel during transfer Construction risk assessment Heavy weather operations – lifelines, lashings, safe areas, etc Crew screening – minimum requirements for each position Maintenance policy – Planned Maintenance System, mooring equipment Vessel suitability inspection survey Job Safety Analysis (JSA) – requirements for doing JSA, site inspection, etc Emergency – responding to fire, musters and drills, fire drills, survival craft drills, rescue drills Incident reporting – types of incident to be reported, method of reporting Incident investigation – type of incident to be investigated, investigation leader, etc Communications and meetings – radio and visual communication, safety committee meetings Assurance audit – types of audits, use of different checklists Vessel approaching limitation, 500 m zone Stop work procedure – who can stop unsafe work Lockout and Tag out (LOTO) – energy isolations on board vessel Cordoning off hazardous areas during critical operations – barricading, safe areas Permit to work (PTW) system – formal documented system for control of work on board vessels Safe movement on deck – transit area, lighting, guarding of openings Entry into confined spaces, inert spaces, toxic spaces

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11.25 11.26 12.0

Hot work – welding, flame cutting, etc Surface swimming

APPENDIX

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12.1

Appendix 1 – Beaufort Scale

BEAUFORT SCALE Beaufort Scale

Knots

Mph

Description

Effect at sea

0

0

0

Calm

Sea like a mirror

1

1-3

1-3

Light air

Ripples but no foam crest

2

4-6

4-7

Light breeze

Small wavelets

3

7-10

8-12

Gentle breeze

Large wavelets, Crest not breaking Numerous whitecaps, Waves 1 – 4 ft high

4

11-16

13-18

Moderate wind

5

17-21

19-24

Fresh wind

6

22-27

25-31

Strong wind

7

28-33

32-38

Very strong wind

8

34-40

39-46

Gale

9

41-47

47-54

Severe gale

10

48-55

55-63

Storm

11

56-63

64-72

Severe storm

12

63

73

Hurricane

70

Many whitecaps, some spray, Waves 4 – 8 ft high Whitecaps everywhere, large waves 8- 13 ft White foam from waves is blown in streaks waves 13 – 20 ft high Edges of wave crest break into spindrift High waves, sea begins to roll spray reduce visibility, 20 ft waves Very high waves 20 – 30 ft, blowing foam gives sea white appearance Exceptionally high waves, 30 – 45 ft high Air filled with foam, visibility reduced, White sea, waves over 45ft high

Effect on land Smoke rises vertically Smoke drifts in wind Leaves rustle wind felt on face Small twig in constant motion, light flags extended Dust, leaves and loose paper rose. Small branches move Small trees sway Large branches move, Difficult to use umbrellas Whole trees in motion Twigs break off trees. Difficult to walk Chimney pots and slates removed Trees uprooted. Structural damage Widespread damage

Widespread damage, rare

PTS 60.2405 OCTOBER 2012

12.2

Appendix 2 – Towing Force Criteria and Calculations (Extract from Oilfield Seamanship, Vol. 5, Barge Moving by Michael Hancox)

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Appendix 3 – Marine Department Malaysia: List of Approved Recognised Organisations As per Malaysian Shipping Notice MSN 48/2008 – 1. NIPPON KEIJI KYOKAI (NKK) 2. BUREAU VERITAS (BV) 3. AMERICAN BUREAU OF SHIPPING (ABS) 4. LLOYDS REGISTER (Lloyds) 5. GERMANISCHER LLOYDS (GL) 6. KOREAN REGISTER OF SHIPPING (KRS) 7. INDIAN REGISTER OF SHIPPING (IRS) 8. DET NORSKE VERITAS (DNV) 9. REGISTRO ITALIANO NAVALLE (RINA) 10. RUSSIA SHIP REGISTER (RS) 11. CHINA CLASSIFICATION SOCIETY (CCS) 12. SHIP CLASSIFICATION MALAYSIA (SCM)

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