Rotork CVA electric valve actuators

The Rotork CVA range of electric actuator is designed to provide continuous, repeatable modulating control with a programmable fail-to-position option. Operating on a 4-20 mA control signal or digital bus, the resolution, repeatability and hysteresis performance of the CVA is quoted at <0.1% of full scale.

Available for the direct-drive actuation of linear or quarter-turn control valves, CVA linear actuators have a maximum rated thrust of 22.2 kN with a maximum stroke of 114.3 mm, while quarter-turn actuators supply a maximum rated torque of 677.5 Nm, enabling the range to operate most control valve types and sizes. Actuators can be specified for single-phase AC or DC electrical supplies.

On loss of mains power, built-in super-capacitors allow the CVA to move the valve to a desired position, programmable as open, close, any intermediate position or stay put. Manual operation is also optionally available.

Actuator set up and configuration is performed using a Bluetooth-enabled PDA or PC running the company’ Enlight software. Every CVA incorporates an onboard data logger, enabling operational data such as valve torque profiles, dwell times, actuator events and statistics to be downloaded for detailed investigation and diagnosis.

Digital control bus connectivity options for the CVA initially include the HART and Foundation fieldbus protocols. The all-electric CVA design also simplifies the process of retrofitting actuators onto existing valves.