It is recognised that reliability and consistent performance are critical in subsea operations where the cost of failure can be extremely high. The operational benefits which the PI73-SS can provide are significant and attractive (see left hand column below). For this reason, Marshalsea Hydraulics and various client companies have run a number of qualification trials of this innovative product. The trials that have taken place are summarised on the right.

Cost savings
	Reduce number of umbilical lines.
	Simplification of Control Module (no HP rated components).
	Development of fields with different well bore shut in pressures at each well without additional HP umbilical lines from topsides.
	Avoidance of very high pressure lines on topside installation, in risers and subsea.
New development opportunities
	Allows high pressure developments to be tied back to existing subsea infrastructure, with lower rated HP pressure infrastructures.
	Mitigation for damaged/old umbilicals – derating, providing reduced OPEX/extended field life for existing infrastructures.
	Selection of downhole valve not dependent on HP pressure and position in wellbore.
	Development of fields where required HP pressure is in excess of current reliable umbilical technology.
Reliability
	Reduce number of moving parts.
	Based on proven, reliable technology (300 topside operational units).
	Reduced number of subsea connections.
Enhanced safety
	Avoidance of very high pressure lines on topside installation, in risers and subsea.

External testing (Wormald)

8 to 1 ratio intensifier, discharge pressure 1,250 bar mineral oil @ 80 deg C (artificially heated), total number of cycles 4,000. Application: topside high temperature/ pressure wells. Projects: Shearwater/Elgin Frankling/ Sable.

Internal testing

5 to 1 ratio intensifier, discharge pressure 1,500 bar; water glycol Transaqua HT at 20°C; total number of cycles 174,000. Application: subsea.

Internal life test

5 to 1 ratio intensifier, discharge pressure 1,500 bar; water glycol Transaqua HT at 20°C; total number of cycles 500,000. Application: subsea, sea water washed. Project: Shell/Cook/Kvaerner.

Internal life test

5 to 1 ratio Intensifier, discharge pressure 1,000 bar; water glycol Transaqua HT at 20°C; total number of cycles 526,000. Application: subsea.

Internal life test

2.5 to 1 intensifier, discharge pressure 950 bar; water glycol HW443 at 20°C; total number of cycles 100,000. Application: subsea control module mounted (dual redundant module), Project: Vigdis/Norsk Hydro/FMC Kongsberg. Click for the published conclusions of this test.

Internal life test

3 to 1 intensifier, discharge pressure 1035 bar; water glycol HW740R at 20°C; total number of cycles 750,000. Application: subsea control module mounted (dual redundant intensifiers). Project: Rhum BP/ABB Offshore. Click for the published conclusions of this test.

External testing (READ)

8 to 1 down hole intensifier (less than 4 in/100mm in diameter); discharge pressure 22,500 psig of water glycol. Application: subsea swaging of casing tube.