How to calculate bolt torque for preload?

T = K × F × d where F = % × Proof Load

What is the efficiency of a riveted joint?

Joint strength / Solid plate strength × 100%. Good design: 70–90%

Required throat size for fillet weld?

a = P / (0.707 × s × L × τ) for parallel load

Fasteners & Joint Design Tools

Professional calculators for mechanical fasteners and joints: bolts, threads, rivets, welds and adhesive bonds. Accurate strength, sizing and safety analysis.

Required Torque

352 Nm

M16 Grade 12.9 • 75% Preload

Fasteners & Joint Design Tools

Comprehensive calculators for mechanical fastening and joint design

Bolt Torque & Preload

Calculate tightening torque for target preload using K-factor

K-Factor Proof Load Clamp Force

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Nut-Bolt Tensile Strength

Proof, yield & ultimate load for metric/inch grades

Grade 8.8–12.9 A325 • Grade 8 Safety Factor

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Thread Geometry

Metric & Unified thread dimensions and tolerances

Pitch Diameter Best Wire 6g/2A Limits

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Rivet Joint Design

Shear, bearing, tearing strength and efficiency

Lap/Butt Pitch & Margin Failure Mode

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Weld Design

Fillet & butt weld throat, leg length and strength

Throat Size Parallel/Perp Load Efficiency

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Adhesive Bonded Joint

Overlap length, shear/peel stress and safety factor

Single/Double Lap Peel Limited Bond Area

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