Offshore Support vessels

A Historical Perspective, Trends and Developments

Capt. Bruce Dann

What are they? And what do they do?

An Offshore Support Vessel can be defined as any vessel that floats and provides support services to the Offshore Industry.They can be any size, shape, conversion or purpose built.

The Beginnings of drilling off the shore

Beach at Summerland California early last century

Early Drilling Louisiana

Early drilling Offshore Ohio

Vessels in use at the Start of the Offshore Industry

SubmersiblesFirst purpose built MODU 1954Submersible ‘Mister Charlie’

Drilling RigsEarly Semi Submersibles

Drillships

First Semi ‘Bluewater 1 converted from a submersible in 1961

Gus 1 first real Jackup 1954Rated for 100 feet

Supply Vessels

M.V. ‘Ebb Tide’ 1956 first purpose built supply vessel

EBB TIDE and the vessels that followed were notable for a number of specialised capabilities and fit out some of which remain today.

• Bridge and accommodation far forward allowing a long after deck for Drill pipe.

• Low aft funnels allowing good visibility for the ship handler and for the cargo to be swung over the deck.

• Twin Propellors

• Powerful Engines (For the day) allowing good manoeuvrability and speed to the rig.

• Open Cargo deck allowing easy cargo stowage.

Derrick Barges

MacDermott DB17DB George R. Brown

Main Types of Offshore Support Vessels in use today and their Development

AHTS (Anchor Handling Tug Supply)

PSV (Platform Supply Vessel)

MODU (Mobile Offshore Drilling Units )

-Jackups (Self Elevating Platforms)

-Semi Submersibles or Semi Subs

-Drillships

Derrick Barges and Heavy Lift Construction vessels

Heavy lift Semi Submersible Transport Vessels

Pipelay Vessels-Rigid Pipe Lay-Flexible Pipe Lay

Specialised Offshore Support Vessels-DSV (Dive Support Vessels)-Multi Purpose Offshore Support Vessels-Seismic Survey Vessels-Floatels (Floating Accommodation Vessels)

Main Types of Offshore Support Vessels in use today and their Development

AHTS

Development stages of AHTS

First Generation

Second Generation

Second Generation

Ulstein 704 (late 70’s)

AHTS continued

Third Generation AHTS

AHTS continued

AHTS continued

Fourth Generation Vessels

New VesselsMost new Vessels have a layout similar to thisNote:

Engine room forwardDrop down bow thruster.Very large winchRail CranesDP2 ClassClean classComfort ClassStern ThrustersHigh Efficiency RuddersTwin sets tow pins and stoppersSplit RollerGirding Hooks right aft360 degree wheelhouse

AHTS continued

Examples of new high capacity AHTSOften over 200 tonnes B.P.Over 20,000 B.H.P.

AHTS continued

PSV

First generation PSV

This vessel was fitted with the original Kongsberg DP System

Second Generation PSV

Late 70s and early 80s

PSV continued

Third Generation PSV

PSV continued

PSV continued

New PSV’s

Jack Up drilling Rigs

Semi Submersible Drilling Rigs Development

The ‘Ocean Digger’ was built in Whyalla in 1967

The ocean Endeavour was built in Perth in 1975

‘The Ocean Epoch’ was built in Mobile Alabama in 1976

These are examples of earlier semi-subs the following slides show the development of this type

Earlier models (upgraded) above

Modern form below

Semi Submersible Drilling Rigs

Modern Semi-subs in Service Today

Semi Submersible Drilling Rigs

DRILLSHIP DEVELOPMENT

The ‘Regional Endeavour’ at left was converted in Newcastle N.S.W. in the mid 1970’s from the Bulk Carrier ‘Mount Kembla’

The ‘Jack Ryan’, left, is a fully DP controlled deep water unit

DRILLSHIP DEVELOPMENT

DRILLSHIP DEVELOPMENT

New Drillships

Heavy Lift Semisubmersible Transport Vessels

MacDermott DB 101 is a mono hull semi with Crane S.W.L. of 2,500 Tons (above)

Heerema’s Hermod (1976) is a catamaran semi with twin crane S.W.L. of 9,000 Tonnes.

Derrick Barges and Heavy Lift Construction Vessels

The Saipem 7000 (left) is the largest of these vessels currently in service with 2 x 7,000 tonne S.W.L. cranes.

Derrick Barges and Heavy Lift Construction Vessels

Pipe Lay Vessels: Rigid steel Pipe

Reel Vessel Apache built 1970’s still operating

Saipem Semi sub pipe lay vessel

D.B. 29

‘Solitaire’ Large Deep Water rigid pipe laying vessel

‘Casterone’ Largest and most modern Rigid pipelaying vessel

Pipe Lay Vessels: Rigid steel Pipe

Casterone the largest rigid pipelayer

Flexible Pipe Lay

Flexible Pipe Lay

FPSO (Floating Production, Storage and Offloading )

SPECIALISED OFFSHORE SUPPORT VESSELS AND THEIR DEVELOPMENT

Purpose built DSV’s began to appear in the early 1980’s

Dive Support Vessels (DSV)

Both these vessels were converted from DSV’s

Both were built in the early 1980’s and still operate today.

Multipurpose Offshore Support Vessels

Modern multipurpose offshore support vessels

‘Far Samson’ currently the highest power and bollard pull Offshore Support vessel.

Bollard pull >430 tonnes continuous

Almost 50,000 horsepower

Modern multipurpose offshore support vessels

Seismic Survey Vessels

Floatels (Floating Accommodation Vessels)

Summary

Offshore Vessel Types

It can be seen from the previous slides that almost all types commenced service as conversions from older units.

Except: submersibles and Jack ups

After conversions proved their worth the various types began to be purpose built and therefore more suited to the task at hand.

Today there are almost no conversions.

Development Requirements for Increasing Water Depth and Harsh Environments

• Diver-less Engineering increasingly necessary

• Increasing ROV Capability

• Even Larger and more powerful vessels than are in use now

• Further development of DP Capabilities

• Almost exclusive use of Sub-sea Production Facilities

• Greater reliance on large PSV’s for supply services

Future Directions

Ship Handling simulator

Arctic FPSO concept

Even Greater Investment in Safety of Personnel, the Environment and Equipment

Future Directions

Dismantling of Old Offshore StructuresFuture Directions

The vessel below is currently under construction as a purpose built vessel to undertake this important work

Concept Vessels for future deploymentFuture Directions

Future Directions

TROLL A PLATFORM The “Troll” platform is the tallest Concrete Gravity Structure (CGS)

so far constructed for use in the offshore industry.

The platform consists of the gravity base structure with 19 base cells, from which 4 shafts extend to support the deck structure. The

overall dimensions are:

DECK Length 176.2m

Width 54m

Weight Approx 22,500 tonnes

Height 81m (to top of drill tower)

BASE Length 161.0m

Width 143.9m

HEIGHT CGS (from top of skirts)

369.4m

Deck Structure 81m

Total Height 450.4m

TOWING DRAFT Inshore 227m

Offshore 227 – 278m

DISPLACEMENT Total 1,027,500 tonnes

THANK YOU FOR YOUR ATTENTION