Pneumatic membrane actuators

These pneumatic actuators operate control valves and are particularly suitable for use in control systems for power plants, refineries, petrochemical and chemical plants. They supply high actuating forces very quickly and meet the requirements for explosion protection without any additional modification. As linear actuators they are directly mounted on control valves.

They are suitable for low pressure valves, but for main control valves they require pressure relief


The pneumatic actuators are differentiated according to whether they are spring-loaded or not.

Spring-loaded actuators move to a safe end position if the auxiliary power fails. The actuators are normally designed so that they can be reversed by turning the actuator head around, without requiring any special equipment. Pneumatic actuators with and without springs are equipped with electropneumatic positioners. For open/closed operation, no positioner is required, but pneumatic actuators can be equipped with accessories such as boosters, blocking valves and solenoid valves according to the customer specifications and operating conditions.

Welland & Tuxhorn mainly uses pneumatic membrane valves and accessories from Samson AG, Frankfurt, whose quality meets today’s requirements.

Advantages of Welland & Tuxhorn pneumatic membrane actuators

  • Simple design
  • Springs for safety position
  • Simple maintenance