During start-up, external leakage from LP Separator Inlet Isolation valve was observed. This valve, which is a fail closed design is fitted to the LP Separator inlet header and is part of the platform ESD system. A leak to sea resulted. Production was immediately shutdown. The valve had not previously exhibited any failure mechanisms of this nature.
All valves of this type or similar should be surveyed and maintenance histories reviewed for each. Any valves with potential to leak in a similar fashion should be considered for isolation and potential repair.
Consideration should be given to modifying the stem packing retention mechanism on all valves of a similar design
Valves of similar design have been identified and are being assessed for repair. Modifications to stem packing retention mechanism will be carried out on all similar valves irrespective of their condition upon inspection. Any valves with potential to leak in a similar fashion should be considered for isolation and removal for repair at the earliest opportunity
12” 1500# RTJ WKM Thro Conduit Gate valve with Axelson pneumatic spring return linear actuator.