April 16, 2012 - Rotork introduced ManPower manually energised spring-return actuators for failsafe valves that are infrequently operated. ManPower greatly reduces installation time and expense since no external electrical, hydraulic or pneumatic power supply is required. Suitable for a wide range of ball, butterfly and plug valves, the scotch-yoke actuators are equipped with a compact, self-contained manually operated hydraulic power pack. A hydraulic hand pump on the power pack is used to operate the actuator and compress the failsafe spring, holding the valve in the desired open or closed position until a failsafe signal is received, at which point the spring will immediately drive the valve to the safe position.
Failsafe operation of ManPower units can be triggered by electrical signals, high or low pressure pilots or fire sensors, enabling the successful fulfilment of many ESD (Emergency Shutdown) and pressure related protection duties in the oil, gas, petrochemical and pipeline industries. Rotork ManPower actuators are available with output torques up to 45,000 Nm, with explosionproof and watertight certification to international standards. A wide range of options includes local position indication, integral limit switches, speed control, high speed operation, local electrical controls, manual reset and corrosion resistant trims. Where space is restricted the ManPower hydraulic module can be located separately from the valve.
Standard units are suitable for a temperature range from -23ºC to +60ºC and equipped with built-in temperature compensation.