Subsea Equipment Past, Present and Future

SUT/MASTS WorkshopDecommissioning and Wreck Removal

Glasgow 1st/2nd October 2015

The beginning

• First subsea completions – Lake Erie 1943, GoM 1961• Typical North Sea system of early 1970’s comprised:

– Xmas trees and well heads– Templates/Manifolds

• Gravity structures• Pin/Suction Piled structures

– Pipelines/PLEMs/Jumpers/Umbilicals

• Experimental subsea separation and pumping - 1980’s• Specs and Codes extensions of land based API codes but

many major oilcos used own “experienced based” standards

• Little thought for decommissioning/removal

Where are we now?

• More reliance on subsea production as reservoirs get smaller and more remote

• Move to deeper water means more subsea• API supplemented by equivalent ISO codes• First HPHT (10k-15k) developments• First steps in large scale subsea processing• Early field abandonment and equipment removal• Push to re-utilise ageing infrastucture, particularly

pipelines, in mature areas

Manifold & Support Structure 175 Tonne

Manifold Suction Pile 130 Tonne

Flowline Termination Assembly & Mudmat110 Tonne

Injection Tree 50 Tonne

Production Tree 55 Tonne

Wellhead & Guide Base 16 Tonne

Flowline Connection3 Tonne

Today’s Equipment

c.70,000 tonnes on the Seabed!

What have we learnt?

• Development of material technologies, particularly:– Forging– Welding exotic materials– Corrosion management

• Equipment performance– Equipment reliability and qualification testing– Systems and equipment testing– Integrity monitoring/diagnostic testing– Predictive maintenance

• Remote intervention technologies• Importance of systems engineering

– Interface management

What’s planned for the future?

• Development of mature areas– Life extension programmes– New developments using existing (ageing) infrastructure

• New developments– Deeper water – Remote locations difficult to support– Higher pressures (20k) and temperatures– Full scale subsea processing

• Field abandonment - requirements typically include– Decommission and decontamination– Well abandonment– Above mudline structures recovered– Pipelines either recovered or abandoned if trenched

Challenges for the future

• Materials – close to the limit of affordable technology– Steel still rules due to cost, manufacturing capacity, “inertia”– Composites and non-metallics only used for special applications– Limited ability to fabricate sophisticated materials in emerging

economies

• Design codes barely keeping up with today’s performance requirements

• Development of autonomous vehicle capabilities • Equipment and infrastructure life extension programmes• Evermore powerful environmental lobby• Cost effective, environmentally friendly field abandonment• Severe CAPEX and OPEX constraints

Subsea Equipment Past, Present and Future

Schiehallion ‘cartoon’

INSIGNIFICANTMAN