SUT Reports
Subsea Well Intervention
SUT
Report on SUT Aberdeen Branch Evening Meeting, Wednesday, 2 September 2009 By Bill Donaldson Current and future subsea technology used for rigless subsea well intervention provided the topic for the first SUT evening meeting in Aberdeen after the summer break at the Hilton Treetops hotel. Tom Leeson of TSMarine chaired the event and opened with a brief introduction to rigless subsea well intervention and the challenges this activity presents to the industry, from the installation of a subsea tree, through life-of-field well maintenance, to final well abandonment following depletion of the reservoir. These include taking control of the well from a vessel and the operating limits to equipment deployment as a result of weather conditions and water depth. Tom also demonstrated the potential cost savings that could be achieved by carrying out well intervention from a vessel compared to using
a conventional drilling rig, if these challenges could be met. Following this introduction, Drummond Lawson of Lewis Limited reviewed existing subsea well intervention equipment capabilities and how the latest developments of new technologies designed specifically for subsea well intervention are promising to open new possibilities to achieve more and to reach deeper water depths. Such technologies include Lewis’ stackable lightweight intervention connector, emergency disconnect package and subsea elevator. Drummond concluded that in order to carry out well intervention from vessels, the industry requires lightweight components, robust reliable designs and technologies that allow multiple well conditions and the full range of water depths to be addressed. To achieve this, brand-
new, fit-for-purpose technologies and a new generation of intervention engineers will be required. The next speaker, Eamonn McGennis, provided an overview of the Well Ops (UK) new well intervention vessel, Well Enhancer, built specifically for operations in the North Sea. Key features of this vessel are its open, multi-purpose tower, which improves access for operations, a deck skidding system that simplifies the movement of equipment, and an automated coiled tubing handling package that removes crew from the deck area. The final speaker was Dick Pearce of Geoprober. Dick pointed out that one of the main limitations for a small, multipurpose vessel to successfully carry out deepwater intervention operations is the safe working load of its handling system. The handling systems on most vessels suspend the loads at
SUBSEA SYSTEMS: TACKLING THE CHALLENGE OF RELIABILITY AND OBSOLENCE Report on SUT Aberdeen Evening Meeting, Wednesday, 7 October 2009 by Adrian Phillips, Aberdeen Branch The chairman began the event by putting two questions to the audience. The first one was: what should the industry do with the ageing subsea equipment currently installed on the seabed? The second: are subsea systems any more or less reliable through the deployment of off-the-shelf technology and open standards? Paul Broadbent attempted to answer the latter by describing a groundbreaking study on the
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common failure modes of subsea control modules. He is currently collecting the last bits of information from the major subsea vendors, so we may have to wait for an answer to this question. Rory McKenzie, on the other hand, described the work Total has been doing to make sure an obsolescence strategy for all components is built into subsea projects, and this will form part of the company’s tender requirements going forward.
Both GE Oil and Gas and Aker Solutions talked about proactive efforts to tackle the challenge of obsolescence and the latest investment programmes to offer upgrade routes to legacy control systems. In the case of SemStar5, which is the latest generation of GE Oil and Gas SEM technology, it is designed to be backward compatible with legacy systems whilst offering the increased benefits of an open architecture.