products 
Diaphragm Actuators 
Fisher® spring and diaphragm pneumatic actuators can be "direct-acting", meaning that air to the diaphragm casing pushes the actuator stem downward. This "air-to-close" action compresses the spring, which in turn pushes the actuator stem back up when the supply pressure is decreased or lost.

Additionally, spring and diaphragm pneumatic actuators can be "reverse-acting", meaning that air to the diaphragm casing causes the actuator stem to move upward. This "air-to-open" action compresses the spring, which in turn causes the actuator stem to move downward when supply pressure is decreased. This is the most common type of diaphragm actuator sold, as the spring action results in a valve "fail-closed" position upon loss of supply air.

Fisher® 1051 and 1052Fisher® 1051 and 1052
Fisher 1051 and 1052 spring-return diaphragm rotary actuators operate splined shaft rotary valves, such as eccentric disc (Fisher 8510B and 8560), 8532 and 9500, CV500, V500, and Vee-Ball valves.
Fisher® 2052Fisher® 2052
Fisher 2052 spring-and-diaphragm rotary actuators are used on rotary-shaft valve bodies for throttling or on-off applications.
Fisher® 3024CFisher® 3024C
The Fisher 3024C actuator is a compact spring opposed pneumatic diaphragm actuator incorporating a cast yoke mounting and is suitable for general purpose actuation of globe valves.
Fisher® 3025Fisher® 3025
Fisher 3025 spring opposed diaphragm actuators position the valve plug in the valve body in response to varying controller or positioner pneumatic output signals applied to the actuator diaphragm.
Fisher 656Fisher® 656
The Fisher 656 actuator is a bracket-mounted, direct-acting, diaphragm actuator for either throttling or on-off service.
Fisher 657 and 667Fisher® 657 and 667
Fisher 657 and 667 spring-opposed diaphragm actuators position the valve plug in the valve in response to varying controller or valve positioner pneumatic output signals applied to the actuator diaphragm.
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