Self-locking alternative to the hex nut 22 February 2022

The CONU counter nut, distributed by REYHER Nchfg GmbH & Co KG, is a new and patent-pending fastener locking device. Compared to conventional hex nuts this counter nut offers a wide variety of advantages depending on the application, such as reduced space requirements and flow resistance, as well as a lower risk of injury.

Due to its self-locking effect, CONU does not require any additional safety and prevents self-loosening. Thanks to its unique shape the counter nut fits into the countersink without any protrusion. The result – an almost flat surface.

The key to CONU’s strength and versatility is its design. Due to the angle difference between nut and countersunk, plus due to the added serrations on the conical surface, the self-locking mechanism starts and then gets stronger the further the nut is pulled into the countersunk hole. This prevents the joints self-loosening. In addition, the joint can be tightened and locked without needing a spanner to hold the nut. In the Junker test (DIN 65151), the constant pre-load force was confirmed despite strong vibrations.

CONU was developed by Fürstenberg Fittings in Hamburg. The counter nut is manufactured by HEWI G. Winker, an automotive supplier and manufacturer of lock nuts and formed parts from Spaichingen in Baden-Württemberg. For the launch phase CONU will be available in sizes M6 to M16 and in two different versions. This means the counter nut can be used with Grade 8.8 and 10.9 high-tensile screws and bolts. 

www.reyher.de

Deputy Editor

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

Biog

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.