Overview

This book details the lessons learned from established ship vetting practices in the oil industry and shows how they can be incorporated into LNG shipping.

Inspections and vetting carried out by charterers, buyers, terminal operators and sellers has been an integral part of ship operations in both oil tankers and LPG carrier operations for more than 25 years and has improved the operating standards. As LNG ships have tended to operate under long-term contractual arrangements they have not been exposed to vetting.

Recent changes in trading patterns have resulted in short-term freight contracts, involving vessels trading to new ports. As a result charterers, buyers, terminal operators and sellers must be sure that the condition, operation and ownership of the vessels are of an acceptable standard, by applying ship inspection and vetting systems to LNG shipping.

This publication draws on information learned from the oil industry and passes it on to all concerned parties involved in vetting LNG ships. It also contains information about the practices of some individual companies and these examples are purely for guidance only.

Content

Contents
The Author iii
Acknowledgements iv
Introduction v
Purpose and Scope v
The Need to Vet Ships v
Section 1: The Trading of LNG by Sea 1
1.1 Overview 2
1.1.1 History of the natural gas and LNG industry 2
1.1.2 The LNG industry in numbers 3
1.1.3 The macro-economic trends affecting LNG supply and demand 4
1.2 Sales and Purchase Agreements 7
1.3 The LNG Supply Chain 8
1.4 Production Projects 10
1.5 Major Exporters of LNG 12
1.6 Major Importers of LNG 14
1.7 The LNG Shipping Business 16
1.7.1 Demand 18
1.7.2 Supply 18
1.7.3 Charter parties 19
1.7.4 Fleet utilisation strategies 21
1.7.5 FSRUs/FLNG 22
1.7.6 LNG bunkering 24
1.7.7 LNG to power 24
1.8 The LNG Terminals 25
1.9 Ship to Ship Transfer 27
Section 2: The LNG Fleet in 2020. A Technical Overview 29
2.1 LNG Carriers 30
2.1.1 Small scale LNG carriers 30
2.2 Floating Storage Regasification Units (FSRU) 31
2.2.1 FSRU regasification system: Closed loop with steam heating 31
2.2.2 FSRU regasification system: Combined open/closed loop with
seawater and steam heating 31
2.2.3 FSRU regasification system: Closed loop with steam heating and
intermediate water/glycol loop 32
2.2.4 FSRU regasification system: Open loop with seawater heating and
intermediate propane loop 32
Ship Vetting and its Application to LNG 2nd Edition viii
2.3 Surveys and Certification. Certificate of Fitness 33
2.4 Cargo Containment Systems 34
2.4.1 Construction materials 34
2.4.2 Tank insulation 34
2.4.3 Types of cargo containment systems 35
2.5 Main Propulsion Systems on LNG Carriers 48
2.5.1 Steam 49
2.5.2 Dual fuel diesel electric (DFDE) 50
2.5.3 Slow-speed 2-stroke diesel engines 52
2.5.4 Slow speed 2-stroke dual fuel engines 52
2.5.5 STaGE propulsion plants 57
Section 3: Vetting on LNG Carriers 59
3.1 The SIRE Programme 60
3.2 The Elements of Vetting 60
3.2.1 The technical approval process. Ship/shore compatibility 61
3.2.2 Assessing ship quality 65
3.2.3 Assessment for use 66
Section 4: The SIRE Vessel Inspection Questionnaire as a Risk
Assessment Tool 67
4.1 Chapter 8 of the VIQ 7 and its Application to LNG Carriers 68
4.2 Policies, Procedures and Documentation 69
4.2.1 Maximum loading rates 69
4.2.2 Reference temperature, saturated vapour pressure and cargo tank
filling and temperature limits 70
4.2.3 Cargo and ballast system mimics and diagrams 72
4.2.4 Cargo plans for partial cargoes and unusual cargo operations 73
4.3 Stability and Cargo Loading Limitations 74
4.3.1 Loading computer/program 74
4.3.2 Verification of inherent intact stability issues 75
4.3.3 Cargo operations manual and its contents 76
4.3.4 Carriage requirements and emergency procedures for LNG 77
4.4 Cargo Operations and Related Safety Management 78
4.4.1 Records of cargo operations and adherence to cargo planning 78
4.4.2 Emergency procedures for dealing with cargo leakage, spillage or
fire involving the cargo 79
4.4.3 Requirements to isolate the electrical supply of the submerged
cargo pump motors during gas freeing operations and verification
of the pump protection systems (shut down in case of low liquid level) 81

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4.4.4 Condition of the cargo, ballast and stripping pumps, eductors and
their associated instrumentation and controls, where fitted, and
evidence of regular testing 82
4.4.5 Cargo pump performance curves and the requirements for cargo
lines and vapour on the system 83
4.4.6 Cargo and ballast system valve’s condition and evidence of testing 84
4.4.7 Cargo system remote and local tank pressure, temperature and level
sensors and gauges, and evidence of regular testing 85
4.4.8 Procedures for addressing the emergency discharge method in the
event of cargo pump failure 87
4.5 Cargo Handling and Monitoring Equipment 88
4.5.1 Condition of tank domes and associated fittings 88
4.5.2 Insulation on cargo or vapour lines and evidence of inspection routines 89
4.5.3 Electrical bonds on cargo and vapour line joints 90
4.5.4 Cargo and vapour line expansion arrangements. Liquid/vapour line
clamps and sliding supports 91
4.5.5 Cargo line and system relief valves 92
4.5.6 Screwed-in connections and cargo pipelines 93
4.5.7 Cargo tank high level alarm systems 94
4.5.8 Records of calibration of key cargo instrumentation (including
temperature and pressure gauges) 96
4.5.9 Cargo measurement and custody transfer system 97
4.5.10 Cargo tank high level and overflow alarms 99
4.6 LNG Cargo Machinery Rooms 100
4.6.1 Bulkhead seals between the compressor room and the motor room 100
4.6.2 Electrical fittings and lighting in cargo machinery rooms 101
4.6.3 Compressor room ventilation system 103
4.6.4 Airlock alarms and their operation 104
4.6.5 Cargo equipment in the compressor room and gas leaks 105
4.6.6 Fixed gas detection equipment and operation and requirements 112
4.6.7 Officers’ awareness of the requirements for setting gas detector
sample points 113
4.7 Cargo Reliquefaction Systems (if fitted) 114
4.7.1 Cargo reliquefaction plant and associated machinery and
instrumentation 114
4.7.2 The ESD system and the gas supply to the engine room 117
4.7.3 Emergency shutdown control to the cargo ESD system fitted on the
reliquefaction plant 118
4.8 Gas Combustion Systems (applicable to ships fitted with a
reliquefaction system or other cargo system that requires a gas
combustion unit to be fitted) 119
4.8.1 GCU unit 119
Ship Vetting and its Application to LNG 2nd Edition x
4.8.2 Testing of alarms associated with the GCU in accordance with the
planned maintenance system 121
4.8.3 Gas fuel piping protection system 122
4.8.4 Automatic gas shut-off system and evidence of regular testing 123
4.9 Void and Interbarrier Spaces and Seals (applicable for all types of
cargo containment) 124
4.9.1 Interbarrier spaces N2 purging system 125
4.9.2 Monitoring of pressure and oxygen content in the interbarrier spaces 127
4.9.3 Relief valves for hold spaces and primary and secondary barriers 129
4.9.4 Means to sample for ingress of water into the insulation space 132
4.9.5 Glycol heating system in the void spaces between cargo tanks 134
4.10 Inert Gas Systems 136
4.10.1 Inert gas system and/or storage and associated pipework 136
4.10.2 Arrangements to prevent backflow of cargo vapour into the
inert gas system 139
4.11 Pressure Relief and Venting Systems 140
4.11.1 Testing for the cargo tank safety relief valves 140
4.11.2 Vent outlet arrangements and protective flame screens 142
4.11.3 Liquid sensors on systems where the pressure relief lines vent
directly through a mast riser 143
4.11.4 Fixed fire-fighting systems on the vent masts, where such systems are fitted 144
4.11.5 Automatic mode operation for the forward vent mast 146
4.11.6 Procedures and authorisation for changing settings and inhibiting alarms 147
4.12 Emergency Shutdown (ESD) System 148
4.12.1 Emergency shutdown (ESD) systems 148
4.12.2 ESD and auxiliary equipment shutdown points 153
4.12.3 Requirements for closing of the manifold valves and tank filling valves
if they form part of the ESD system 157
4.12.4 Fusible plugs on the liquid domes and in the vicinity of the manifolds 158
4.12.5 Reliquefaction plant trip in the event of activation of the ESD (where a
plant is fitted) 159
4.12.6 Secondary tank pressure management systems in use at sea 161
4.12.7 Override procedure for the alarms and ESD trips 162
4.13 Manifold Arrangements 163
4.13.1 Manifolds, associated valves, blank flanges and pressure gauges 163
4.13.2 Safe access for connection and disconnection of cargo lines and
restricted access to the manifolds during cargo operations 164
4.13.3 Checking of offshore manifolds during cargo transfer for manifold
valve leakage 165
4.13.4 Flange connections 166

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4.13.5 Manifold strainers 167
4.13.6 LNG spill arrangements 168
4.13.7 Liquid spill and manifold drip tray arrangements 169
4.13.8 Draining and purging prior to disconnection of the MLAs 170
4.14 Safety Equipment 175
4.14.1 Protective equipment 175
4.14.2 Safety equipment and donning of safety equipment 176
4.14.3 Firemen’s outfits 177
4.14.4 Chemical dry powder systems 179
4.14.5 Water spray systems 181
4.14.6 Fixed fire-fighting and extinguishing systems installed within
enclosed spaces containing cargo handling equipment 182
4.15 Cargo Hoses 183
4.16 Cargo Lifting Equipment 184
4.17 Ship to Ship Transfer Operations (applicable if the ship is utilised for
regular commercial ship to ship cargo transfer) 185
4.17.1 Procedures and equipment for LNG cargo transfers 185
4.17.2 Risks and requirements during ship to ship operations 189
4.17.3 Person in overall advisory control (POAC)/STS Superintendent 191
4.17.4 Ship to Ship transfer checklists 193
4.17.5 CDI/ICS/OCIMF/SIGTTO ‘STS Transfer Guide’ recommendations 194
Section 5: Assessing Risk 197
5.1 Observations 198
5.2 The Role of the Vetter in Assessing Risk 198
5.3 Continuous Improvement 198
Appendices 199
Appendix A – Contains a list of the full LNG carrier fleet (listed by size)
>65 km3 as of the beginning of 2020, including FSRUs 201
Appendix B – Contains the list of the LNG fleet ordered by ship age,
oldest to newest 209
Appendix C – Contains LNG fleet ordered alphabetically, by ship name 217
Appendix D – Shows the orderbook of LNG carriers >65 km3 as of the
beginning of 2020, including FSRUs 225
References

Details

Title: Ship Vetting and its Application to LNG, 2nd Edition
Number of Volumes: 1
Edition: Second
Number of Pages: 242
Product Code: WS1804K
ISBN: ISBN 13: 978-1-85609-881-6 (9781856098816), ISBN 10: 1-85609-881-8 (1856098818)
eBook ISBN: ISBN 13: 978-1-85609-882-3 (9781856098823), ISBN 10: 1-85609-882-6 (1856098826)
Published Date: June 2020
Binding Format: Paperback
Book Height: 220 mm
Book Spine: 300 mm
Weight: 1.50 kg
Author: Capt. Juan Pablo Presedo