Reaction Nuts

HEICO-TEC® Reaction Nuts

HEICO-TEC® Reaction Nuts are the ideal complement to the HEICO-TEC® Tension Nut for use with through-bolted connections.

If you already enjoy the advantages of HEICO-TEC® Tension Nuts for active pre-tensioning, you need an equivalent reactive nut on the opposite end. Due to their special shape, HEICO-TEC® Reaction Nuts can flex elastically. And the more elastic a bolted joint is, the more durable and secure it is against untightening and loosening.

Advantages of the HEICO-TEC® Reaction Nut:

  • Even load distribution through concave contact surface
  • Preload losses are effectively reduced
  • No additional space is required, tension nuts and reaction nuts have the same dimensions

Compatible with ISO 898-2

HEICO-TEC® Reaction Nuts meet all requirements of ISO 898-2. They therefore have the same strength as conventional hex nuts and can replace them 1:1. However, they must not be used for active pre-tensioning, rather only on the opposite reactive end.

Construction and function

  1. The nut body (1) is screwed onto the bolt like a conventional nut with the main thread, but is not tightened. Tensioning is performed from the opposite end, e.g. with a HEICO-TEC® Tension Nut.

  2. Since the nut body only rests on the outer diameter, a hardened washer (2) protects the clamped parts from the contact pressure.

Function HEICO-TEC® Reaction Nut

The contact surface of the HEICO-TEC® Reaction Nut is concave and can therefore flex elastically in the direction of the bolt axis. This increases the elasticity of the bolted joint. A short bolted joint is susceptible to fatigue failure and self-loosening. With the HEICO-TEC® Reaction Nut the joint performs like a bolted joint which is 2-3 thread diameters longer and thus more durable and safer. This is accomplished solely by replacing the hex nut with a HEICO-TEC® Reaction Nut!

Product overview HEICO-TEC® Reaction Nuts

HEICO-TEC® Reaction Nut product overview (ISO metric)

HEICO-TEC® Reaction Nut product overview (ISO metric)

HEICO-TEC® Reaction Nut product overview (inch sizes)

HEICO-TEC® Reaction Nut product overview (inch sizes)

Fields of application

heavy industry

heavy industry

cement industry

cement industry

pump and pipe technology

pump and pipe technology

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