Lindapter steelwork clamps and DTI washers

Lindapter has confirmed that Direct Tension Indicators (DTIs), or Load Indicating Washers to BS EN 14399-9:2009, are compatible with its Type AF High Slip Resistance clamp when used with property class 8.8 & 10.9 fasteners to BS EN 14399-3 System HR or BS EN 14399-4 System HV.

Renowned for developing innovative connection systems that eliminate the need to drill or weld steelwork, Lindapter continually carries out research to monitor construction industry standards and good practice. Lindapter recognises that, while it already publishes recommended tightening torque figures for the Type AF clamp when using HR and HV fasteners, some contractors are more familiar with DTIs as a method of indicating that correct preload has been achieved in the bolt. For guidance on the correct use of DTI washers, please refer to BS EN14399-9:2009 and DTI manufacturers’ instructions.

The preload achieved using the DTIs is utilised by Lindapter’s robust Type AF clamp to produce high slip resistance up to 35kN and tensile loading up to 62.5kN per bolt. The ultimate strength of the bolt assembly is the limiting factor for the Type AF’s ultimate tensile performance.

The Type AF is available in sizes M12 to M24 and is supplied hot dip galvanised as standard.

 For further information, including Safe Working Loads for the product range, please request the Lindapter catalogue by calling +44 (0)1274 521 444 or visit the website