April 2, 2014 -Rotork announces CMR-250/GB3 electric actuator for choke valves CMR-250/GB3 actuator meets requirements for low power, high torque modulating control in a compact package for applications including severe service upstream wellhead production and injection valves. The low power requirement and a 24VDC option enables solar powered and battery back-up supplies to be introduced in remote locations, whilst the all-electric technology delivers considerable system simplification and economy in any environment by eliminating the on-going costs associated with an instrument air supply. Easily adaptable to suit any type of valve, the CMR-250/GB3 delivers a maximum output torque of 45 Nm (400lbf in).
Available for a range of single-phase or DC power supplies, the design combines a brushless motor with permanently lubricated, high efficiency gears to achieve accurate, responsive and continuous modulating control. Rotary output speed is adjustable down to 50% of full speed. The compact actuator enclosure is environmentally sealed to IP67 as standard and available with ATEX, IECEX, FM and GOST hazardous area certification. The wide ambient operating temperature range (-20 to +65ºC for explosionproof models and -30 to +70ºC for watertight models) facilitates long-term reliability and maintenance-free operation in the harshest of environments. Actuator set-up is performed in a logical menu-driven process using an internal electronic 6-segment LCD display and pushbuttons.
User selectable adjustments encompass speed, dead band, zero and span, command signal type, standard or reverse action and loss of signal position. A standard 4-20mA signal is used for control and feedback, whilst digital network options include Rotork Pakscan, HART, Profibus, Modbus and Foundation Fieldbus. A hard-wired RIRO (Remote-In-Remote-Out) option is also available.