SSIV meaning in oil and gas

Subsea Isolation Valve

A most critical valve in a Subsea safety system is the Subsea Isolation Valve (SSIV) and its job is to Close on Demand to minimize the risk to the environment and the asset. Its purpose is to provide a reliable automatic sub-sea isolation system to prevent the loss of containment from the pipeline in the event that the riser ruptures. This valve is located between the flowlines and the risers and is normally situated on the Flowline Termination Assembly (FTA) about 500 metres from the facility. The SSIV is the means of connecting the flow-lines and/or the export pipelines to the rigid risers and, thereafter, to a fixed or floating offshore platform. SSIVs are installed, in subsea flowlines as a fundamental safety design criterion and, depending on the application, the valve choice will feature a Metal Seated Hydraulic Spring Return Actuator and either a Through Conduit Gate Valve or a Ball Valve coupled with a Swing Check Valve to prevent back flow.