Prestressed Power Springs (SPIR'ATOR)

Prestressed Power Spring
How it Works
Our SPIR'ATOR prestressed power springs are produced by reverse winding a NEG'ATOR spring on an arbor and enclosing it in a case or retaining ring. Rotational energy can be obtained from either the arbor or case or, when linear motion is required, through use of a pulley and cable attachment.

With torque and deflection being equal, a SPIR'ATOR generally requires 20% less space than a conventional power spring, and also yields a flatter torque gradient. 


Power springs are ideal for use in applications requiring counterbalancing, winding and retrieving.

The Material
Prestressed power springs from Hunter Spring are made from 301 High Yield Stainless Steel. Other materials including Elgiloy, Inconel, or high-carbon steel can be used upon request for custom applications.

Key Features
- Low torque gradient yields usable torque throughout the operating range
- Can provide more than twice the turns of a conventional power spring
- Higher prestressing generally permits the use of thinner material thus a smaller package size than conventional power springs
- Compact and lightweight

Custom Springs
Hunter spring does not stock prestressed power springs. Springs are designed for customer specific applications only. Use the design worksheet to specify your requirements and allow our Application Engineers to provide you with a design to meet your needs.

We invite you to consult us. We may well be able to formulate a custom solution that will surprise you with its efficiency and versatility.



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