Sealing nuts

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Sealing bolt-nut joints

SEAL LOCK® sealing nuts are an economical solution for reliable seals against gaseous and liquid media under high pressure.



SEAL LOCK® sealing nuts are one-piece structural components.
Sealing against leakage can be executed in the thread or bearing face. These components are used e. g. for hydraulic or pneumatic systems or for fuel systems.
With SEAL LOCK® sealing nuts, high-strength screwed connections can be realised without loss of preload-forces - they can even be used in repeated screwings.


The most important benefits at a glance

  • One-piece component
  • Captive seal
  • Seal resistance against many oil types and solvents
  • From -40 °C to +110 °C
  • High preload-force due to metal bearing face
  • No loss of preload-force due to set O-ring
  • 5 repeat screwing-unscrewing cycles possible
  • Dimensions M 6 - M 16
SEAL LOCK® – Prior to bracing / In braced condition

Prior to bracing / In braced condition

The SEAL LOCK® sealing nut has many benefits over to multi-piece solutions consisting of cap nut, locknut and two sealing discs.
With our solutions you can save assembly time and realise optimal screwed connections without loss of preload-force at minimum space requirements.

For information on the technical data of our SEAL LOCK® sealing nuts, see our product catalogue. Here you also find information on possible special designs.


Examples of application SEAL LOCK®

  • Sealing and locking adjusting screws in the return chamber of a way valve block in a hydraulic control system

  • Locking a set screw on the pressure-limiting valve inside toothed feed pumps

  • O-ring and lock on control lever axle for an airplane refuelling device

  • Screwing and O-ring of automobile gear box

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Sealing nuts with reduced installation effort
and prevention against loss
0500/12.02 English PDF / 927 KB

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SEAL LOCK® – sealing nuts


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