Tightening torques

Especially important when ensuring the tightness of flange joints in pipelines. The required value can be affected by factors such as the minimum sealing surface compression (depending on the tightness class), the maximum permissible temperature-dependant surface compression of the seal and the friction factor between the bolt and the nut. The required tightening torque can be determined mathematically with the aid of DIN EN1591-1.