Designed and developed specifically for quarter turn ball valves, butterfly valves, and V-port valves (fail close or fail open), the ACHEM ASD series spring-diaphragm rotary pneumatic actuators were designed by using advanced spring-diaphragm structure and a crank-rocker mechanism, and adopts the design idea of separating the pressure medium room from the mechanical transmission mechanism, offering very unique product advantages for high-precision control valve.The actuators can be operated by air (not filtered), water, mineral-based hydraulic fluid within a temperature range from as low as -60°C (-78°F) to as high as 200°C (392°F).

1. Flexible selection of working media
The ASD spring-diaphragm rotary actuator features an independently expandable and contractible media room design, offering flexible selection of working media such as compressed air (no cleaning requirements), water, or mineral-based hydraulic oil. 2. Can operate within the range of -60°C to 200°C
The independent pressure media room is equipped with a diaphragm of nylon66 fabric blend or aramid fabric blend with NBR, LNBR or Composite silicone coated. Equipped with the corresponding diaphragms, the ASD spring diaphragm rotary actuators can operate normally within a temperature range from as low as -60°C (-78°F) to as high as 200°C (392°F).

3. Continuity of torque ou tput and smooth start and end
Due to the expandable and contractible media room under pressure and the continuous motion of mechanical transmission, the ASD spring diaphragm rotary actuator exhibits strong continuity in its output torque, ensuring valve start and end smoothly.

4. Lighter, faster and high-torque output
ASD spring-diaphragm actuators not only offer a lightweight design with high output torque but also enable fast opening and closing. Under the same output torque conditions, compared to scotch yoke actuators, large spring-diaphragm actuators creat an output torque (spring to close) of 10.94 Nm/kg, whereas scotch yoke actuators only provide 6.36 Nm/kg.

5. Removable & Replaceable multiple drive bushing
The drive bushings of the actuator are available with keyed holes, double D holes or double square holes or with the stem of square, star or namur. It is important to note that these drive bushings comply with the ISO 5211 , and are interchangeable, and can be easily replaced at the worksite. 6. Reversible in field fail closed or fail open
The operation of fail closed to fail open can be quickly and easily changed in the field by simply inverting the bushes and the actuator.

7. Travel Stops
The actuators have double adjustable travel stops that allow to be adjusted to the fully open (90°) or the fully closed (0°) within ±5°.

8. Corrosion Resistant
All the fasteners are with dacromet coating, the parts inside are with electrophoretic coating and the outside parts are with electrophoretic coating + polyester powder coating. Meet the corrosion protection requirements for moderate corrosive environments.

10. Universal mounting pads for direct mount
The actuator offers a combination of different mounting pads (ISO5211 + JB) that allow you to directly replace existing Spring-Diaphragm Actuator or mount directly to new and existing quarter turn valves.

The ASD2, 3, 4, 5 and 7 series actuators use a single-spring structure, while the 6 and 8 series employ a double-spring structure. There are significant differences in their external dimensions,which should be closely monitored during selection.