Product category:
Fasteners, threaded and non-threaded
News Release from: Cross Manufacturing Co (1938) | Subject: Spiralock inserts
Edited by the Engineeringtalk Editorial
Team on 28 November 2006
Wire thread inserts perform on plastics
The latest news from Cross Manufacturing reports on an unexpected development in the application of locking wire thread inserts that is truly ground breaking.
The latest news from Cross Manufacturing reports on an unexpected development in the application of locking wire thread inserts that is truly ground breaking A pioneering and lengthy programme of vibration testing on Cross Spiralock thread inserts has demonstrated a locking performance that is equally good in steel, aluminium - and plastic
This article was originally published on Engineeringtalk on 28 Nov 2003 at 8.00am (UK)
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These extraordinary results offer the possibility of using Cross Spiralock inserts in a multitude of new industries where plastics are in common use.
The ability of the Cross Spiralock insert to grip with immunity to the effects of vibration and allow dismantling and reassembly with no deterioration in performance should prove attractive in many applications.
For example, one of the plastics tested, Sustarin C, is widely used for precision machined components in the food, pharmaceutical and hygienic industries, whilst GRP (glass reinforced plastic), which was also tested, is the staple diet of the boat building industry.
In addition, plastics are increasingly used for motor car panels, where the capability for swift assembly and replacement is a positive advantage.
Cross Spiralock wire thread inserts rely on a unique thread profile which transmits the tightening loading down the full length of the bolt to achieve their proven locking performance and resistance to vibration.
This is an innovative departure from the distorted thread design of conventional prevailing torque alternatives.
The Spiralock profile not only produces a free running performance when inserting the bolt but is also unique in enabling multiple re-use with no deterioration in the locking performance.
Comprehensive testing programmes in metals have confirmed an unrivalled resistance to vibration induced loosening, however the equally good performance in plastics was not expected and has surprised the engineers at Cross.
In addition to Sustarin C and GRP, the inserts have been tested in Nylon 6 and even PET, the low grade plastic typically used for bottles and packaging.
In all cases an M6 x 3D insert was used with an ordinary bolt and the results were virtually identical in all these materials.
Cross's Spiralock Insert Test Engineer Chris Whittock enthuses: "We didn't expect this and further testing is now taking place, but designers and engineers in the manufacturing industries should definitely watch this space".
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