AKRIVIS
MACHINE
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Thread Calculator
Tools
Fastener Torque & Preload
Calculate required tightening torque based on clamping force, size, and friction factor.
Inputs
Nominal Bolt Diameter (in)
% of Yield Strength
Yield Strength (ksi)
K-Factor (Friction Coefficient)
0.12 - Anti-seize / Heavily Lubricated
0.15 - Lightly Lubricated / PTFE
0.20 - Plain / Unlubricated Steel
0.25 - Zinc/Galvanized / Rusty
Custom...
Custom K-Factor
Threads Per Inch (TPI)
Calculate
Reset
Formulas used:
Tensile Area (As)
= π/4 × (D - 0.9743/n)²
Target Preload (F)
= As × (Yield × %)
Torque (T)
= K × D × F
Results
Required Tightening Torque
0 ft-lbs
Tensile Stress Area
0.000 in²
Target Preload Force
0 lbs