Products + Tools

Perfect Lock Bolt America Inc has introduced the Perfect Lock Bolt (PLB) – a dual-threaded bolt and nut system engineered to reduce or eliminate self-loosening problems in the fastener industry.

Available to the European market, the PLB consists of a dual-threaded bolt shaft and two nuts of different thread pitches. The first, or primary nut on the shaft, is a coarse thread nut. The outer, or secondary nut on the shaft, is a fine thread nut or ‘lock nut’.

When subjected to a self-loosening force in any form, the primary nut moves away from the preloaded pressure along the bolt shaft faster than the secondary lock nut. Under any loosening force, the primary nut and the secondary lock nut move away from the pre-loaded pressure at different rates, creating a mechanical lock between the two nuts.

The PLB is designed to reduce and even eliminate many common problems associated with external loosening forces such as wind, heat-related expansion and contraction, and vibration. The bolt is ideal for a variety of applications such as bridges, industrial machinery, construction and agricultural machinery, heavy duty vehicles, aerospace, high-speed rail, wind generation, or in any situation where vibration is an issue of concern.

The PLB’s revolutionary new design is fully reusable – causing no damage to the bolt, the nuts, or to the equipment being secured by this patented fastening system – and is coated with environmentally friendly coatings. The Perfect Lock Bolt has passed and exceeded the Vibration Masters Junker Vibration 25201-B test, and is available in different grades, sizes, lengths and finishes.