New three-piece locknut system 01 July 2013

Ferrule-Lock™ has launched a new three-piece locknut system that it says has greater holding power for high vibration applications.

Ferrule-Lock’s patented design utilises a simple and effective innovation borrowed from the tube fitting industry, which it says is easy to install and outperforms other locknut fasteners. It is a three piece system comprised of two identical Ferrule-Lock™ nuts and a ferrule. The bolt is customer supplied to meet the application.

The first Ferrule-Lock nut is threaded onto the bolt and torqued to the designed clamp load and standard specifications. The ferrule is slipped over the bolt and seated in the chamfered face of the clamp nut. The second Ferrule-Lock nut - acting as a jam nut - is threaded onto the bolt until the ferrule seats into the chamfer of the jam nut. The final step is to tighten the jam nut to compress and bind the ferrule into the two Ferrule-Lock nuts, creating a joint that will not vibrate loose.

The Ferrule-Lock system has been rigorously tested using the Junker Test, with the testing procedure consisting of a fastened joint between a stationary and a movable plate. A load cell is placed on the bolt and the two plates are fastened together under a specified clamp load and subjected to vibration using an amplitude of 10 percent of the diameter of the bolt and 12.5 hertz for 1,000 cycles.

An added benefit of the Ferrule-Lock system is that the load on the clamp nut has no impact on the vibration proof quality of the Ferrule-Lock system. The only requirement is that the ferrule be compressed between the opposing Ferrule-Lock nuts. This feature is very useful in applications where minimal clamp load is required.

“Ferrule-Lock is designed to provide a serviceable joint. It is a simple matter of loosening the jam nut, removing and discarding the ferrule, and removing the clamp nut as you would normally. Ferrule-Lock nuts are reusable with a new, replacement ferrule.”

Claire Aldridge Editor t: +44 (0) 1727 743 889

Having spent a decade in the fastener industry experiencing every facet – from steel mills, fastener manufacturers, wholesalers, distributors, as well as machinery builders and plating + coating companies, Claire has developed an in-depth knowledge of all things fasteners.

Alongside visiting numerous companies, exhibitions and conferences around the world, Claire has also interviewed high profile figures – focusing on key topics impacting the sector and making sure readers stay up to date with the latest developments within the industry.