Heavy Duty Scotch Yoke Actuators - THD Series

  • Pneumatic Actuators for Quarter-Turn Valves and Dampers
  • Torques to 1,600,000 in. lbs.
  • Available in Double Acting and Spring Return

The Triac line of heavy duty scotch yoke actuators offer a broad range of torques to 1,600,000 in-lbs. The THD series is designed to operate ball, butterfly, plug valves, dampers or any device that requires a quarter-turn movement for on-off or throttling service. Our standard offering is the symmetrical design yoke that delivers maximum torque at both ends of the 90º cycle. The square slide bearing with guide bar gives high cycle life and smooth stroke while minimizing wear points. As with all Triac actuators, our THD series comes with a complete line of accessories, including jackscrew, hydraulic overrides, limit switches, solenoids and positioners. A-T Controls also offers complete mounting hardware to integrate our actuator with any quarter-turn valve, damper or louver.Contact us for application assistance.

Heavy Duty Scotch Yoke Actuators Feature:

  • Torques to 1,600,000 in-lbs.
  • Travel adjustments ±8º for clockwise and counter-clockwise strokes
  • Nitrile rubber piston O-rings offer excellent sealing and wear. Optional low and high temperature seals and lube are available
  • RTFE Guide Band supports piston while providing smooth operation and extended life
  • Extra large, strong piston rod for long life and torque transmission
  • Namur accessory mounting pads permit mounting standardization of limit switches, positioners, etc.
  • Ductile iron center body
  • Modular design allows for installing power groups and spring cartridges so that actuators may be set up for different air pressures and for Fail Clockwise and Fail Counter-clockwise
  • Rugged heavy duty steel pressure cylinders chrome plated for long wear and corrosion resistance
  • Safe, welded spring cartridges with numerous options for a broad range of air pressure conditions
  • Alloy steel, corrosion resistant and heat treated springs designed and manufactured for long high cycle life
  • Steel slide block, bronze slide bearings to minimize friction and provide long cycle life*
  • Visual position indicator

*Not available on the S09 pressure group.

Heavy Duty Scotch Yoke Actuators
phone 513.247.5465    fax 513.247.5462
AVU Registrations, Inc. Management System Certificate
Certified to
ISO-9001: 2008
Canadian Registration Numbers
TA-Luft Certified Ball Valves
Firesafe Certified Ball Valves
API 607
4th Edition

Valves & Actuators
ABS Approved

CSA Group
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