Bolt Torque

Written by Jerry Ratzlaff on . Posted in Fastener

Torque, also called moment of force, is a rotational moment. It is a measure of how much twisting is applied to tighten (turn) the nut on a bolt.  When bolting flanges together or anything else tor that matter, tightening the nut stretches the bolt adding pressure to the gasket.  The bolt are designed to stretch a bit acting like a spring.  Different factors can affect the torque like number of threads, oil, rust, type of material, etc.

Bolt Torque formula

$$\large{ T = \frac {k\;d\;p} {12} }$$

Where:

$$\large{ T }$$ = torque

$$\large{ p }$$ = desired clamp load tension

$$\large{ d }$$ = nominal diameter

$$\large{ k }$$ = torque coefficient (dimensionless)

Tags: Equations for Torque