Subsea Skid Assemblies

TIS Manufacturing has been integral in the design and creation of several subsea systems, including the new Subsea Intervention System on the new Well Enhancer Vessel by Helix Well Ops.

The system is part of the Subsea Intervention Lubricator, (SIL), a 7-3/8” bore single-trip system, the subsea equipment was tested towards the end of last year where it was successfully deployed via the vessel’s integrated skidding and handling system. The SIL allows wireline well intervention from a dynamically-positioned vessel. The system proved successful working in adverse weather conditions with wave height of five metres and winds of 45 knots, heave at the moonpool rarely exceeded two metres and the vessel’s performance exceeded expectations.

TIS was also involved in the design and manufacture of an earlier 5” system on the Well Ops vessel SEAWELL, the SIL on the Seawell can be deployed from a derrick without a conventional blowout preventer (BOP) and riser system. The SIL has both passive and active heave compensation, with up to 65-ton capacity in active mode, and it is possible to rig up the tool and remove a tree cap within 24 hours.

The SIL was the forerunner of technology used in riserless light well intervention. The SIL takes proven technology one step further by creating a single-trip system that gives access to large-bore subsea assets in deeper water. The unit can also deploy its SIL in a single piece, which can save up to 10 hours per run. The system now in its third generation, set an industry standard for efficient interfacing with vertical and small bore concentric subsea trees.

These subsea modules have been meticulously designed to meet the highest safety specifications, and to connect seamlessly with surface based equipment. TIS used state of the art 3d modelling software, with a specially designed module to aid in this type of subsea design. On the Well Enhancer TIS also supplied an HPU and several reelers to the project so was aware of the interaction that might be required throughout the equipment.

Much of the Well Enhancer SIL was built in TIS’ workshop in Aberdeen, utilising the expertise which had been honed during the building of the similar system on the Seawell.