The L75 Series of Limitorque electric valve actuators from Flowserve Corp., Irving, Tex. (Flowserve.com), activate quarter-turn valves and other rotary devices. They use either a splitphase ac-reversing or dc motor to drive a valve through a sealed, permanently lubricated gear train. They can turn devices clockwise or counterclockwise through selected arcs of 20 through 300°.
Actuators are available in eight sizes and produce torque to 3,000 lb-in. The standard coating on the housing is baked polyester, but special coatings are available for extreme environments. Other options include cyclelength controller, feedback potentiometer, position-indicator board, and a heater and thermostat.