What is a Partial Stroke Test?
SIS standards dictate proof test frequency for the final element in a safety system. Operators usually perform an offline full stroke test during a scheduled shutdown because it impacts the process. But when a safety integrity function requires more frequent testing, users perform a partial stroke test while the valve is online without impacting the process.
During the partial stroke test, the valve is stroked a portion of its total travel to verify it is not stuck and to uncover other dangerous failures. It exercises the shutdown valve to verify it will operate and move to its safe position in the case of a safety demand.
How It Works
Cost Savings
A partial stroke test safely extends the time between full stroke tests. It eliminates the need for expensive test panels and skilled personnel for testing.
