Reliability Management of Surface-Controlled Subsurface Safety Valves for the TOGI Project

This paper describes Norsk Hydro and SINTEF's efforts to obtain higher reliability of surface-controlled subsurface safety valves (SCSSV's) for the Troll-Oseberg gas-injection (TOGI) project. Because of the severe consequence of system failures, reliability management was fully implemented on the TOGI subsea production system. The methodology used combines reliability theory with operating experience. Data bases with relevant field data, design review techniques, valve prototype testing, and review of test results are other elements of the reliability management program. Although this specific application was for SCSSV's, the methodology presented in this paper can easily be applied to systems where the consequence of failure is severe.