Seabed processing systems and solutions
Alpha Thames Subsea
REAct™ - Linear actuator
Fail-safe actuators commonly energise the spring relative to the valve position, making the drive mechanism work against both the spring and the valve during normal operating duties. REAct™ is unique in that the spring stack used to close/open the valve in an emergency, operates totally independently of normal valve operation. Initial operation of the valve energises and locks the fail-safe spring stack in place, before normal valve operation takes place. Disconnection of power to REAct's™ unique locking mechanism will release the energy stored in the spring stack, thereby closing (or opening) the valve in the event of an emergency. No clutches or back-drive mechanisms are involved; therefore the system is totally reliable.
REAct™ is a two-part design utilising a minimum number of components; it comprises an oil filled, pressure-balanced, electro-mechanical actuator and an electronic drive package that may be housed in the benign environment of a local subsea control module (SCM). The two-part design was developed after investigation into high-reliability components in the aerospace industry.