TaskJunction

Bolt Pattern / Group Calculator

Maximum bolt shear from eccentric direct load and overturning moment.

Calculate the most heavily loaded bolt in a multi-bolt pattern subjected to combined direct shear and torsional moment.

Bolt Pattern / Group Calculator

Inputs

Bolt 1
Bolt 2
Bolt 3
Bolt 4

Results

Number of Bolts
4
Group Centroid
(0.0, 0.0)mm
Polar Moment (J)
20000mm²
Direct Shear per Bolt
2000.0N
Max. Resultant Bolt Load
2549.5N

Formula Used

Fdirect = P/n  |  Ftorsion,i = M·ri/J  |  J = Σ(dx²+dy²)
Enter bolt coordinates relative to any reference origin — centroid is calculated automatically. Direct shear assumed acting in the Y-direction; adjust bolt orientation accordingly for your load case.

⚠ For preliminary design and educational use only. Verify all results against applicable codes and standards before use in production or safety-critical applications.

About this calculator

Part of our Mechanical Calculators collection. Beams, bolts, springs, gears, bearings, and core ME calculations.

How it works

Calculates resultant shear force on the most-stressed bolt in a group subjected to direct shear and an eccentric moment using the elastic method.

Enter your values in the inputs above and click CALCULATE. Results appear on the right without a page reload. No login and no server upload.

Privacy and accuracy

Every calculation runs locally in your browser. Your design data never leaves your device. Results are intended for preliminary engineering work. Always verify critical designs with qualified review and applicable standards before production use.

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