Gýrol® Fluid Drives

Howden Gỳrol® Fluid drives are used to control speed and to absorb shock and torsional vibration and we can offer a wide range of designs that enable our customers to operate rotating equipment with a “soft start” option and at variable speeds with minimal capital cost requirements.

Detailed specifications

Class 6    8 Single RA sizes     200-40,000 HP      Up to 3,600 RPM
Class 5    7 sizes                      500-1,400HP         Up to 1,800 RPM
Class 4    7 sizes                      100 - 3,500HP       Up to 1,800 RPM
Class 2    8 sizes                       2 - 2,250 HP         Up to 1,800 RPM

Key Features

  • ​AKA hydraulic coupling or hydrodynamic drive.
  • ​Power transmitter.
  • ​Variable speed drive.
  • ​Provides a soft start.
  • ​Has no mechanical contact between driver and load.
  • ​Filter Packages.
  • ​Temperature Switches and Gauges.
  • ​Pressure Switches and Gauges.
  • ​Heaters.
  • ​Couplings and Guards.
  • ​Tachometers.
  • ​Sole Plates.
  • ​Pump Bases.
  • ​Vibration Monitoring Equipment.


  • ​​​Efficient up to 98% of input speed.
  • ​Reliable.
  • ​Rugged for operation in dirty environments and outdoors.
  • ​Provides infinitely variable speedy control.
  • ​Transmits power smoothly and without shock.
  • ​Available for variable or constant torque applications.
  • ​Turndown ratios 5:1 for variable torque.
  • ​Turndown ratios 4:1 for constant torque.
  • ​Provides no-load setting.


  • Variable and Constant torque applications.
  • Pumps Fans & Blowers.
  • Compressors.
  • Process Equipment.
  • Extruders.
  • Mixers.
  • Crushers.
  • Mills.
  • Conveyors.

Find your contact

Change location

General enquiries: 

Nick McLean


+44 141 885 7500

If you would like to submit an enquiry please get in touch.

Parts & Service

Lifetime Support

Our lifelong aftercare service will supply original replacement parts, support you with maintenance and installation, and even train your own engineers in maintenance techniques. We keep detailed plant records almost indefinitely, and regularly supply spare parts for machinery over 50 years old.