Designed in response to customer demand, Dutch valve safety product manufacturer Netherlocks has developed the facility for entirely remote operation of its FAITH Partial Stroke Test (PST) system for ESD and HIPPS* valves. This means that the mechanically-safe, fully-online testing of these critical valves can now be initiated and performed from the safety and convenience of the control room.
The FAITH system at all times facilitates the partial stroke testing of valves, without any risk of overshoot or process interruption. The test is never aborted without getting results, and the unique design means that tests can be performed at real speed – just as it would be for real operation in an emergency. The mechanical limitation on the degree of valve closure guarantees there is no danger of actual shutdown or upsetting the plant due to overshooting of the test angle.
The FAITH’s simple mechanical design is key to the reliability of the system. It is a universal add-on product which is fitted directly between the valve and the actuator and replaces the original couplings. During partial stroke testing, FAITH’s mechanical steel blocking pins ensure that the valve can only turn to the preset test angle (i.e. 20 degrees). This also allows for maintenance during production.
All FAITH systems can be customized to fit directly between the valve and actuator without additional brackets. Models are available for both linear and rotating actuators, and electronic switches can also be added to the FAITH system to allow the control room to monitor the test.
