The Fisher 667-34-3/4 actuator is a spring-opposed diaphragm actuator designed for reverse-acting control valve applications, offering a 3/4-inch travel range. It belongs to the 667 series, known for robust construction and dependable pneumatic performance.

• Actuator Series: Fisher 667
• Size: 34
• Travel Range: 3/4 inch (19 mm) — indicated by the “3/4” designation
• Action: Reverse-acting — air pressure pushes the diaphragm downward to open the valve
• Spring Type: Spring-opposed; spring compression sets the zero position
• Mounting: Top-mounted on compatible Fisher control valves
• Manual Override: Compatible with side-mounted handwheel assemblies for manual control
• Maximum Supply Pressure: Typically up to 2.4 bar (35 psig), depending on spring configuration
• Materials: Steel diaphragm casing with corrosion-resistant components
• Applications: Ideal for throttling and on-off control in industries like oil & gas, chemical processing, and power generation