DECLUTCHABLE GEAR OPERATOR

The compact DG declutchable gearbox provides efficient, precise performance for quarter-turn manual override valves. The gearbox is specially designed to offer quick and simple operation of the highest torque valves when the air or power supply fails.

The wormshaft is disengaged from the quadrant teeth during normal operation. The quadrant transmits the rotary motion of the actuator via a coupling onto the valve shaft. For manual operation, the worm is swiveled into the quadrant teeth by means of a lever and then fixed. Now the valve and the pneumatic actuator can be operated via the gearbox.

When used with single-acting actuators, it is necessary to operate against the spring load of the actuator. All gearboxes are self-locking so that any chosen position can be driven to and maintained. In order to prevent the pneumatic actuator from being actuated by pressure during the manual override operation, the actuator must be equipped with a safety locking system and/or a shut-off valve must be mounted onto the gearbox. The shut-off valve (3/2-way valve) is automatically activated as soon as the lever for clutching or declutching the worm shaft is operated. Once the lever has been operated, the pneumatic actuator is vented and simultaneously the inlet air pressure is cut off. The position is maintained until the wormshaft is declutched. Take into account the max. spring force of the actuator and the max. output torque of the valve together as a magnitude when selecting the gearbox for single-acting actuators.
 

Model: DG Aluminium die cast body Compact design, light weight Easy switch from manual to pneumatic actuatar ISO5211 direct mount to valve and actuator Precision gear desgin Torque outputs

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