Flange Bolt Torque Calculator
Convert a target bolt load into tightening torque using the K-factor (nut factor) method, in newton metres and pound feet.
Inputs
Results
- Torque per bolt
- 300.0 N·m
- Torque per bolt
- 221.3 lb·ft
- Total load (8 bolts)
- 800.0 kN
Formula used
T = K × F × d
F is the target bolt load in newtons, d the nominal bolt diameter in metres and K the nut factor, which depends on thread condition and lubrication.
The nut factor is empirical and varies widely with lubrication, thread condition and surface finish, so the result is an estimate. Always follow the torque values, tightening pattern and passes specified by the flange, gasket or bolting standard used on your project.
Results are theoretical calculations based on the values you enter. Actual weights and quantities vary with manufacturing tolerances. Confirm requirements with our team before ordering.
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