1 Introduction

1.1 General

As offshore oilfields are discovered in increasingly deeper waters the capabilities of existing installation and pipelay vessels need to be increased for the targeted 3000m water depth.

At this water depth typical pipe-lay tension is reaching the 1000tons mark.

This document is the second edition (1^st edition October 1999) and reviews the existing, upgraded and new built or converted DP Deepwater installation vessels, and covers the key issues such as:

Typical Deepwater installation tasks and related constraints, as further described in Chapter 2.
Interface engineering that is needed to properly load and install a product (e.g. flowlines, umbilical) or structure with the adequate means (cranes, winches, tensioner, lay ramp, etc.) is further analysed in Chapter 3.
Different lay techniques (Steep S-lay, J-lay, Reel-lay) are further analysed in Chapter 4 with its constraints, limitations, advantages and disadvantages.
Because of the water depth and the scattering of FPS mooring lines, wells, flowlines, umbilical and other subsea structures, Deepwater installation vessels must be equipped and operated in 'dynamically positioned', exclusively by means of propeller and thruster forces. The dynamic positioning system and class requirement are further detailed in Chapter 5.
Installation means and laying equipment are further described in Chapter 6.
Subsequent Chapter 7 will provide general description of typical Deepwater installation vessels (i.e. heavy lift vessels, Deepwater pipelay vessels, and Deepwater flexible pipes and umbilical lay vessels).
A new Chapter 8 have been implemented to present the heavy transportation vessels.
Finally the annexes will provide the main particulars and descriptions of the available Deepwater installation vessels, along with the addresses of the installation contractors.

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1.2 Codes, Standards, Specifications and Reference Documents

1.2.1 Codes & Standards

[1]	DNV_No2_22	Rules for Certification of Lifting Appliances
[2]	DNV-OS-F101	Submarine Pipeline Systems
[3]	DNV-OSH206	Loadout, Transport And Installation Of Subsea Objects
[4]	DNVGL-RU-SHIP	Rules for Classification of Ships
[5]	DNVGL-ST-N001	Marine Operations And Marine Warranty
[6]	IMCA_M-103	Guidelines for the Design & Operations of DP vessels
[7]	IMCA_M-140	Specification for DP Capability Plots
[8]	IMCA-M-103	The Design and Operation of Dynamically Positioned Vessels
[9]	IMCA-M-149	Common Marine Inspection Document
[10]	IMCA-M-166	Guidance on Failure Modes and Effects Analyses (FMEAs)
[11]	IMCA-M-220	Guidance on Operational Activity Planning
[12]	IMCA-M-247	Guidance to Identify DP system Components and Their Failure Modes.
[13]	IMO-COLREG	Convention on the International Regulations for Preventing Collisions at Sea
[14]	IMO-MSC-Circular-645-1580	Guidelines for Vessel with Dynamic Positioning Systems
[15]	MTS-DP-Operations-Guidance	Part 2 (Appendices 2 & 3) Marine Technology Society DP Operations Guidance to aid in the Safe and Effective Management of DP Operations Part 2 Appendix 2 (DP Project/Construction Vessels) Appendix 3 (Logistics Vessels)
[16]	MTS-DP-Tech-Comm-DP-Guidance	DP Guidance, Part 1 Marine Technology Society DP Operations Guidance to aid in the Safe and Effective Management of DP Operations Part 1
[17]	NDG-Ltd-0029-ND	Noble Denton Guidelines For Submarine Pipeline Installation
[18]	OCIMF-DP-information-paper	Dynamic Positioning Assurance Framework Risk-based Guidance

1.2.2 TOTAL Standards

[19]	CR-EP-EXP-408	Simultaneous Operations of Subsea Handling and Production (Subsea SIMOPS)
[20]	CR-EP-LSO-400	Manned Underwater Operations
[21]	CR-EP-LSO-401	ROV Operations
[22]	GM-EP-LSO-601	Lifting Management System
[23]	GM-EP-LSO-612	Maintenance & Inspection of Lifting Equipment
[24]	GS-EP-LSO-306	Selection and Operation of Dynamically Positioned Vessels
[25]	GS-EP-PLR-100	Risers, Submarine Pipeline Systems
[26]	GS-EP-PLR-109	Design, fabrication and testing of submarine unbounded flexible pipes and risers
[27]	GS-EP-PLR-401	Risers, Installation of Submarine Pipelines
[28]	GS-EP-PLR-406	Risers, Storage and Transportation of Lines Pipes
[29]	GS-EP-SPS-038	Subsea Systems, Subsea Structures design & fabrication
[30]	GS-EP-STR-401	Loadout, seafastening, transportation and installation of offshore structures
[31]	GS-EP-STR-404	Structural, Marine Aspects For Load-Out, Transportation And Installation Of Offshore And Onshore Structures

1.2.3 Deepwater Reference Books

[32]	T084-EN001	Riser Systems
[33]	T084-EN002	Pipeline Systems
[34]	T084-EN003	Subsea Production Systems
[35]	T084-EN004	Umbilicals
[36]	T084-EN005	Subsea Control Systems
[37]	T084-EN006	Deepwater Installation Methods
[38]	T084-EN007	Subsea Connections & Tie-in Methods
[39]	T084-EN008	Deepwater ROV & Tools
[40]	T084-EN009	Offshore Platforms & Floaters and Mooring Systems
[41]	T084-EN010	Field Architectures
[42]	T084-EN011	Subsea Processing and Pumping Systems

1.3 References

This study is based on the following sources

Industry available documentations such as OTC papers
In-house technical database
Installation contractor vessel leaflets

1.4 Definitions & Abbreviations

1.4.1 Definitions

Capability plot: A theoretical polar plot of the vessel capability for specific conditions of wind, waves and currents from different directions and with different thrusters combinations.
Deepwater: Water column comprised between 500m (1600ft) and 1500m (5000ft) of water depth..
DP system: It comprises all equipment, sub-systems, control systems and back-up systems that directly or indirectly effects the position keeping ability of the vessel; such as power system control, monitoring system, thruster system, references, etc.
DP vessel: Dynamically Positioned vessel means a unit, a ship or vessel which automatically maintains its position and heading with respect to one or more references, exclusively by means of thruster forces.
Flowline: The conduit system e.g. steel pipeline, flexible line, bundle, etc., divided in two parts: static "sealine” section resting on seabed and dynamic "riser" section ‘hanging’ from seabed to surface
Redundancy: Ability of a system or component to maintain or restore its function, when a failure has occurred
Reliability: Ability of a system or a software program to perform its required function without failure to cause an interruption in DP control in a period of 2000 hrs of DP operation
Riser: "Dynamic" part of flowline connecting sealine to the termination point of platform

1.4.2 Abbreviations

API: American Petroleum Institute
CAMO: Critical Activity Mode of Operation
CRA: Corrosion Resistant Alloy
DARPS: Differential Absolute and Relative Positioning Sensor
DGPS: Differential Global Positioning System
DP: Dynamic Positioning
DP: Dual Port
FLET: Flowline End Termination
FMECA: Failure Mode Effect and Criticality Analysis
FPS: Floating Production Systems: TLP, SPAR, FPSO, Semi-submersible, etc.
FPSO: Floating Production Storage and Offloading
FSHR: Free Standing Hybrid Riser
GMAW: Gas Metal Arc Welding
GTAW: Gas Tungsten Arc Welding
HAZID: HAZard Identification
HAZOP: HAZard and Operability
ILT: In-Line Tee
IMCA: International Marine Contractor Association
IMO: International Maritime Organization
IQI: Image Quality Indicator
LARS: Launch & Recovery System (e.g. ROV handling system)
LRS: Lloyds Register of Shipping
MPP: Multi-Phase Pump
MTS: Marine Technical Society
NDE: Non Destructive Examination
NDT: Non Destructive Testing
OD: Outside Diameter
PGMAW: Pulsed Gas Metal Arc Welding
PiP: Pipe-in-Pipe
PLEM: Pipeline End Manifold
ROV: Remotely Operated Vehicle
SAWL: Submerged Arc Welding Longitudinal
SCR: Steel Catenary Riser
SIMOPS: SIMultaneous OPerationS
SMAW: Shielded Metal Arc Welding
SMTS: Specified Minimum Tensile Strength
SMYS: Specified Minimum Yield Strength
SPS: Subsea Production System (i.e. subsea structures such as X-mas trees, manifolds, etc.)
SSBL: Super Short Baseline
SSCV: Semi-Submersible Crane Vessel
SSU: Subsea Storage Unit
SWL: Safe Working Load
TAMO: Task Appropriate Mode of Operation
TLP: Tension Leg Platform
TMS: Tether Management System
UFR: Umbilical, Flow Lines and Risers
USBL: Ultra Short BaseLine
WD: Water Depth
WI: Water Injection
WT: Wall Thickness

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