Catalog
pages for Scotch Yoke ¼ Turn Pneumatic Actuators
Scotch Yoke pneumatic actuators are designed for ¼ turn valve
applications and capable of high torque output required by plug, ball and
butterfly valves. These pneumatic valve actuators are available in
both double acting and spring return versions covering a torque range up to
2,212,500 in-lbs!
Less costly than rack and pinion style
actuators, Scotch Yoke style actuators typically output higher torque.
Scotch Yoke pneumatic actuators output a non-linear torque, which is well
suited for butterfly valve applications but not advantageous for ball valves
used for proportional flow control. Although Scotch Yoke style pneumatic
actuators are physically larger than rack and pinion designs, they have fewer
components and are more reliable. Thus Scotch Yoke style actuators are
typically used for large butterfly valves to minimize actuator cost and
maximize reliability.
Scotch Yoke pneumatic actuators have an interchangeable and modular design
to simplify maintenance. Their weatherproof enclosure is made from
ductile iron or fabricated from carbon steel, providing a superior
strength-to-weight ratio. Scotch Yoke actuators provide reliable performance
in the harshest environments.
Features and Options:
ISO 5211 flanged
Yoke mechanism has adjustable range of ± 6º
NBR and PTFE seals
40-90 PSI of ≤ 40μm filtered and lubricated air required
Can be oriented for fail closed or fail open
Options:
Hand wheel override
Hydraulic override
Extended mechanical travel stop