RINGFEDER® Shrink Discs Help Wind Turbines Transmit High Torques

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Northern Power Systems, a large United States manufacturer of wind turbines, needed a reliable, economical locking device for their systems. In the past, they tried different splined or keyed shafts, but found that these connection methods were too expensive and created a weak point in the shaft connection.

Shrink disc advantages:

Shrink discs are the modern method for creating a mechanical shrink fit. Our RfN 4091 and Rfn 4071 shrink discs offer many advantages over keyed ways and splined shafts including smaller and lighter shafts, less cost of ownership and ease of maintenance.

They consist of either one or two thrust rings with tapered bores and a mating tapered inner ring. By tightening the locking screws, the thrust rings are drawn together, compressing the inner ring and applying pressure to the outside of the hub, clamping it to the shaft.

In addition, when using a key or spline, parts must be aligned precisely. With a shrink disc, you don’t need that level of precision.


Technical features:

Ringfeder’s RfN 4091 and 4071 secure all types of hubs onto shafts and axles, replacing traditional shrink fits, keys and polygon connections and splined shafts. Some technical features include:

  • Maximum reliability.
  • A slitted inner ring.
  • Easy replacement, mounting and removal.
  • Low susceptibility to contamination.

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Now, the company uses Ringfeder shrink discs for its 60 and 100 kilowatt wind turbines to transmit higher torques than standard key shafts. Here’s a look at what makes shrink discs an ideal choice.