Bolt Clamp Force Calculator
Bolt clamp force is the preload left in the fastener after tightening. Estimate it from torque, nut factor and nominal diameter, then check the result against proof load and torque scatter.
bolt clamp force calculator bolt clamp load calculator bolt clamping force from torque
Clamp force equation
F = T / (K * d)
Inputs that matter
- Torque: tightening torque applied to the nut or head.
- Nut factor: empirical friction factor for the actual assembly condition.
- Diameter: nominal bolt diameter, such as 10 mm for M10.
Caution
Torque control can scatter preload widely. Use measured K or stretch/angle control for critical joints.
Related pages
- Bolt preload torque calculator - calculate clamp force, proof-load utilization and preload scatter.
- Bolt preload formula - equation and nut-factor definitions.
- Bolt preload explained - joint mechanics, proof load targets and preload scatter.
- Bolt torque spec chart - starting torque values by size and grade.