Bolt Bearing Stress Calculator

Inputs

Total shear load (F)

Total load shared by the bearing fasteners.

Bearing fasteners (n)

Number of bolts or pins sharing the load equally.

Bolt / pin diameter (d)

Use the diameter bearing against the plate or hole.

Plate thickness (t)

Thickness of the plate being checked in bearing.

Allowable bearing stress (sigma_allow)

Material bearing stress limit before safety factor.

MPa

Safety factor (N)

Allowable design stress is sigma_allow / N.

Default result

Bearing stress(sigma_b)

83.33MPa

Pass

Average stress on projected bearing area d*t.

sigma_b = F_bolt / (d*t).

Also computed

Utilization(U)0.6667

Bearing stress divided by design allowable.

Load per fastener(F_bolt)5,000N

5 kN · 1,124 lbf

Projected bearing area(A_b)60mm²

A_b = d*t per fastener.

Design bearing stress(sigma_d)125MPa

allowable / safety factor.

Required thickness(t_req)4mm

Holding diameter fixed.

Required diameter(d_req)6.667mm

Holding thickness fixed.

Method notes 3 notes

Load is divided equally across the entered fastener count. Eccentric bolt groups need a bolt-pattern force check first.
Projected bearing area is d*t per fastener. This is an average bearing check, not a contact-stress distribution.
This does not check bolt shear, bolt tension, plate tear-out, net-section tension, edge distance, fatigue, prying or code-specific resistance factors.