DIN 65946:2017-07

This standard specifies a method of determining the coefficient of friction in the thread when tightening bolts or nuts under specified conditions. It is only applicable to comparison purposes, such as a comparison of bolt/nut assemblies with different surface finishes or for cases where different lubricants are to be assessed. Application-oriented tightening tests relevant for determining the coefficient of friction in bolt/nut assemblies forming part of specific structural units are not covered in detail in this standard given the complexity of requirements involved. This standard is based on the assumption that there is a linear relationship between torque, clamp force and coefficient of friction across the whole measuring range. This standard is intended for aerospace applications only. For general technical applications, see DIN EN ISO 16047.