The 685 is a double-acting piston actuator that provides accurate, high thrust output for short to long travel applications. This actuator is designed for use with a variety of medium to large Fisher sliding-stem control valves including the easy-e™, FB, TBX, HP, EH, and 461.
The 685 family is available in several configurations to cover a wide range of application requirements. Typical travels range from 25 to 610 mm (1 to 24 inches) and cylinder diameters range from 305 to 660 mm (12 to 26 inches). Thrust capabilities extend to 354 kN (79,000 lbf) and above with special constructions.
The 685 can be used with the FIELDVUE™ DVC6200 digital valve controller for throttling applications, or with switching valves for on-off control. This actuator can also be fitted with volume boosters for fast stroking requirements.
- Broad application coverage - standard constructions offer travels of up to 610 mm (24 inches) and cylinder diameters of up to 660mm (26 inches). Even larger constructions are available upon request.
- Low Friction - low friction piston seals and either chrome plated or fluoropolymer coated cylinder bores reduce sliding friction and wear.
- Wide temperature range - standard constructions offer a temperature range of -40 to 93⁰C (-40 to 200⁰F), however higher or lower temperatures are possible. Special constructions can operate as low as -54⁰C (-65⁰F) and as high as 204⁰C (400⁰F).
- Manual override - an optional side-mounted handwheel is capable of extending or retracting the actuator manual and can be engaged at any position from full open to full closed.