SMS-TORK 3 Position Pneumatic Actuator

The 3 Position Pneumatic Actuator is an SMS-TORK rack and pinion actuator that adds a controllable middle position between the fully open and fully closed ends of a standard 90 degree stroke.

Operated through a triple 3/2-way directional valve, the actuator drives to fully open on the first signal, then to a half-open position adjustable between 30 and 60 degrees on the second signal, and finally fully closed on the third, which is the sequence used to top off a tank or hopper at full flow and then switch to a reduced flow to prevent overfill before shutting off completely. TORK produces the 90 degree version across sizes 40, 60, 80, 100 and 120, with 120 and 180 degree 3-position actuators available as special-order builds. It shares the same extruded aluminium body, ISO 5211/DIN 3337 valve connection and Namur VDI/VDE 3845 solenoid/switchbox connection as the rest of the RA platform.