What is the Perfect Lock Bolt?

The Perfect Lock Bolt (PLB) is a self-loosening resistant, dual thread, mechanically locked bolt and two nut fastener. The PLB is designed for repeated use and comes in a wide variety to meet your application needs.

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Dual Thread Bolt’s Locking Mechanism

Two nuts having different helical paths, moving along the same bolt shaft, is the key to the PLB and its ability to resist loosening even under severe vibration-shock.

PLB Cross-Section

The primary coarse nut and secondary fine nut travel along two distinct, separate, helix angles causing them to move at different speeds relative to the bolt shaft. The primary coarse nut travels faster than the secondary fine nut and when subject to vibrational forces the slower traveling fine pitch nut prevents the coarse pitch nut from loosening as with traditional bolt, nut and washer fastener.

  • Different grades/classes available
  • Stock sizes & lengths
  • Custom sizes & lengths
  • Remarkably simple yet ingenious design
  • Engineered to last & be reusable
  • Mechanically Locked to Resist Loosening from Vibration
  • Reduced Liability
  • Greater Safety
  • Reduced Maintenance Cost from Joint Loosening

Perfect Lock Bolt Applications

Steel Frame Buildings • Bridges • Steel Towers • Crushers • Construction Machinery • Wind Driven Electricity • Generators • Cranes • Ships • Playground Equipment • Elevators • Commercial Vehicles • Aviation • Aerospace • Machinery • Industrial Machinery • Engines • Scaffolding • Trucking • Vibration Conveyers • High-Speed Rail • Amusement Parks


Bolt Installation