One of the main concerns for users of portable valve actuators is controlling the torque. It’s right to be concerned about the potential for damaging the valve or the gear winding mechanism as the valve reaches it’s fully open or fully closed position.
Some of the portable actuators have built-in torque limiters. For those which don’t have integral controls, a de-clutch device is available like the one shown. It’s factory set at the maximum torque limit. It fits between the portable device output shaft and the input shaft of the valve or penstock gearbox.
For the operator, he can use the portable actuator as normal, safe in the knowledge that it will ‘click’ and disconnect drive when the upper set limit is reached.
For more information on portable valve actuators (aka valve drill), click here