How tight a torque ?
1. Always observe equipment manufacturer's specifications.
2. If none are available, determine required torque on a test rig.
3. Otherwise, refer to national standards.
Torque values are given for 85% fastener yield strength, for class "A" torque control accuracy (< ±5%).
1. Friction coefficient
Actual friction coefficient depends on fastener and component condition, and affects tightening. Choose the appropriate table according to type of fasteners used (i.e. µ = 0,10, 0,15 or 0,20).
2. Fastener grade
The grade of a fastener denotes its quality (best is 12.9). Check the appropriate column for the fasteners used.
3. Tightening torque (Cs)
Torque values are listed in newton-metre (Nm) for each type of fastener.
4. Tensile load (Fo)
This force in newtons (N) is the equivalent of an Fomax value.
The above information, for which Facom accepts no liability, is given as a guide only.