Bolt Torque & Preload Calculator
ISO metric and SAE — using T = K · D · F.
Common: 60–75% for reusable joints, 90% for permanent.
Results
Tightening torque
81.78 Nm
≈ 60.32 ft-lb
Clamp load (preload)40890 N
Yield load54520 N
Proof load48140 N
About this calculator
Uses the short-form torque equation T = K · D · F where K is the nut factor, D is nominal bolt diameter, and F is target clamp load. Real-world torque can vary ±25%; for critical joints, validate with a torque-tension test fixture or use VDI 2230 with measured friction coefficients.
