ARD Backstopping Clutch | Formsprag Clutch

  • Holding torque exceeding 200,000 ft.lbs.
  • Virtually unlimited continuous speed capability through lift-off sprags
  • Many units with greater than 200,000 hours of maintenance-free operation

Formsprag Clutch was instrumental in the development of the long-life Anti-Rotation Device (ARD) on the reactor coolant pumps of pressure water reactors and continues to support the installed base of ARDs by offering field inspections, factory rebuilding and new ARDs with improved bearing performance.

Product Features

Standard Formsprag ARD design features:

  • Lift-off sprags for no-contact running, no heat generation and long-life exceeding 10-year maintenance-free operation between recommended inspections
  • Dynamically balanced hydrodynamic babbitted bearings and races for minimal wear and heat generation
  • Accommodation for pressurized oil flow, and monitoring systems to measure temperature, pressure, and vibration to ensure performance
  • Balanced torque arm to positively prevent reverse rotation
  • 100% dynamically tested at the factory
  • ISO 9001:2000 and AS9100 Rev. B

Other Formsprag Clutch Nuclear Power Industry applications include:

  • Backstops for various pumping systems
  • Cooling tower fan backstops
  • Overrunning clutches in turning gear drives
Click on image below to download pdf. To order hard copies of literature click here.

Service Manual

  • Centrifugally Disengaged Vertical Backstop ARD Installation

Related Literature

Contact Info

Formsprag Clutch
23601 Hoover Rd.
Warren, MI 48089 - USA
Toll Free: 1-800-348-0881 (Press #1)
Phone: 586-758-5000
Fax: 586-758-5204

ARD Anti-Rotation Device Clutches
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