W paper WM selmcd fa pmmmdon by the OTC Prcgrun Comminec following review of infornmtion conwwd in an &tract mbmmd by the mttbor(s) Contcnu of the pspcr, u presented, bw'e not been reviewed by the OITshore Technology Confcfmce md we subject 10 axmc!ion by the uhf,) The mated, M presented, & m neccss.n Iy mfl w my pm iii." of the OtTslwre Tcchno Iogy Ccmf.rcme or IUoflbn Pmmisicm 10 WY i$ rexmzed to an abstract of mw more than 103 wrcb Illu.tr.tIOns may MI bc mpud ti Aamct dmuid oman mnspmcw tcknowledsmcn: of whae md by whom Lhe paper wu Abstract This paper reviews the continuing development of gate valve and actuator technology for subsea completions extending into ultra deep water. l%e basic technical challenges inherent to subsea valve actuators are reviewed, along with the various factors which affect the design and performance of these devices in deepwater applications. The high external ambient pressures which occur in deep water, coupled witti high specific gravity hydraulic control fluids, are shown to have a significant impact on the performance of the actuators. This paper presents design & analysis methods and the verification test procedures which are required to develop and qualify new deep water actuator designs.Gate valve actuators of the type described in this paper are currently in use on subsea christmas trees on the world's deepest subsea wells offshore Brazil (water depths >3000 feet). New applications of the deepwater actuators are in process for upcoming Gulf of Mexico subsea production systems in water depths approaching 6000 feet. The actuator/valve development method described in this paper has been confirmed by performance verification testing of full scale valves& actuators using a hyperbaric chamber to simulate ultra deepwater operating conditions. Performance of the test valves & actuators correlated very well with analytical predictions. Test resuhs have confirmed that the new valve actuator designs will satisfy API 17D performance requirements for water depths up to 7500 feet, well in excess of the upcoming GOM application.

No abstract