Compact Automation Class-Act (CL) Valve Operator Model 742

Features: • Heavy Duty Double Acting Ball Valve Systems • Valve sizes from ¼” to 3” • 140 in.lbs to 800 in.lbs • Spring Return Valve operators • Single acting with spring close or open • Valve Operator Systems Spring Return operators are formed by bolting a spring return unit to a double acting Val-U-Act operator. The return movement is effected by a clock-type spring which is pre-tensioned to about half the operator torque. The amount of pretension is large, compared to the rotation and therefore the torque does not vary more than 20% over the rotation. Spring returns are factory-installed and adjusted and have a worm drive adjustment for setting or changing spring pretension. By inserting a socket key into one end of the worm the spring pretension can be very easily increased or decreased to suit operating conditions. To increase pretension, turn the worm clockwise; to decrease, turn counterclockwise.