The Rotork Pressure Safe® failsafe hydraulic control system has recently introduced an economical and reliable line break detection solution for remote pipeline or wellhead valves and critical process applications where mains electricity or fluid power sources are not available or unreliable.
The failsafe actuator can be linear or quarter-turn, fail open or close, with cylinder operating pressure up to 3,000 psi. The compact, self-contained Pressure Safe® provides Emergency Shutdown (ESD) protection by automatically exhausting spring-return actuator pressure when pipeline pressure exceeds a high or low level set-point. The Pressure Safe® hydraulic control system has a 3-way high and low pressure pilot valve which will trip the control system when line pressure is outside of the normal operating range. This is ideal for use as the final mechanical element in safety systems designed in accordance with IEC 61508 and IEC 61511.
When combined with a solenoid or process sensor the control system can provide automatic process control based on one or more process variables including pressure, temperature, level, velocity and chemistry. An integral hand pump is fitted for re-pressurising the actuator and the unit’s dump valve can be manually opened.