Scotch Yoke Pneumatic Actuator

Scotch Yoke Pneumatic Actuator
I. Product Overview
The Scotch Yoke Pneumatic Actuator is a high-torque, highly stable pneumatic drive device designed for quarter-turn valves such as ball, butterfly, and plug valves. Compared to rack-and-pinion designs, the scotch yoke mechanism delivers higher output torque, more uniform force distribution, and superior fatigue resistance, making it particularly suitable for high-pressure, large-bore, and heavy-duty industrial valves.
The unit features a compact structure, rapid operation, and low failure rates. It can be equipped with accessories such as solenoid valves, limit switches, positioners, and manual override handwheels to enable automated on/off and modulating control.
II. Structural Features

• Scotch Yoke Transmission: Converts linear piston motion into rotational torque; amplifies end-stroke torque for powerful valve actuation.
• Double-Acting/Single-Acting Options: Double-acting for rapid opening/closing; single-acting with spring return for automatic, safe reset upon loss of power or air supply.
• High-Strength Housing: Hard-anodized aluminum alloy offers wear resistance, corrosion resistance, and a long service life.
• Adjustable Travel: Mechanical limit stops at both ends allow for precise ±5° adjustment, ensuring proper valve sealing.
• Universal Mounting Standards: Complies with ISO5211 mounting standards, ensuring compatibility with the vast majority of industrial valves.
  III. Applications
  Widely used in industries such as petroleum, chemicals, natural gas, power generation, water treatment, desulfurization and denitrification, marine, and metallurgy. Suitable for high-temperature, high-pressure, large-bore, and high-torque valve applications; serves as a replacement for older, heavy-duty actuators. IV. Technical Parameters
• Operating Air Supply: 0.4–0.8 MPa clean compressed air
• Operating Temperature: -20°C to +80°C (high/low-temperature versions available upon request)
• Output Angle: 0°–90°
• Protection Class: IP65
• Actuation Type: Double-acting, Single-acting (spring return)
  V. Installation and Operation Instructions
• Before installation, ensure the valve’s open/closed status aligns with the actuator’s rotation direction, and verify the air supply is clean and free of oil, water, or impurities.
• Gradually introduce air after connection to test the opening and closing actions; fine-tune the travel limits using the adjustment screws at both ends.
• When using with a solenoid valve, ensure the voltage and airflow direction are correct to prevent jamming caused by incorrect installation.
• Single-acting models automatically reset upon air supply loss, meeting requirements for emergency safety shut-off.
• Ensure smooth operation without jamming or abnormal noise; regularly inspect the air filter and the condition of seals.
  VI. Summary of Advantages
  Features high torque, strong load-bearing capacity, wear resistance, high stability, and easy maintenance; it is the preferred actuator for automating large-diameter valves in high-pressure applications.