In double acting actuators, compressed and processed air is supplied to obtained desired movement of actuator. In actuator, air supply channel provision is made such that supplied air can be transfer at both sides of the rack as per requirement. Higher air pressure at one side of rack cause movement of rack at other side. Contact face of either sides of rack are made leakproof by means of O-rings and secondary sealing rings.
Automated valves and flow components for industrial valve control application.
Rack & Pinion Actuators
Double Acting Actuator
Principle of Operation
Operation
• CCW : CCW is standard at M-torQ Controls India
- Air to port A apply pressure on rack, generates force on faces of rack. This applied force cause pinion to rotate counter clockwise and rack outward while exhaust air passes through port B.
- Air to port B apply force on other side and generates clockwise movement of pinion and inward movement of rack. while exhaust air passes through port A.
• CW :
- Air to port A apply pressure on rack, generates force on face of rack. This applied force cause pinion to rotate clockwise and rack outward while exhaust air pass through port B.
- Air to port B apply force on other side and generates counter clockwise movement of pinion and inward movement of rack. while exhaust air passes through port A
- Output Torque of Double Acting Actuators
- Output torque table of Double Acting Actuators
Sizing of Double Acting Actuator
Recommended factor of safety for double acting rack and pinion actuators under normal working conditions is 20% to 30%
- Valve torque defined by valve manufacturer = 100 Nm
- Torque considering recommended factor of safety (1+30%) = 130 Nm.
- Air Supply = 6 bar.
Example:
Referring output torque table of double acting actuators, we can select an actuator MTDA-095 model for which an output torques are matching the requirement.