Clevis Pin Calculator

Inputs

Joint load (F)

Load carried by the clevis pin.

Pin diameter (d)

Clevis pin diameter.

Shear planes (n)

Use 2 for a typical clevis pin in double shear.

Center eye thickness (t_e)

Thickness of the center lug or rod end eye bearing on the pin.

Fork lug thickness (t_f)

Thickness of one outside fork lug.

Bearing center span (s)

Distance between the approximate reaction centers of the two fork lugs for the pin-bending model.

Allowable shear stress (tau_allow)

Pin material allowable shear stress before safety factor.

MPa

Allowable bearing stress (p_allow)

Allowable bearing stress for the lugs before safety factor.

MPa

Allowable bending stress (sigma_allow)

Pin material allowable bending stress before safety factor.

MPa

Safety factor (N)

Design allowable stress is allowable / safety factor.

Default result

Max utilization(U)

0.8383

Pass

Worst of shear, bending and bearing checks.

Also computed

Pin shear stress(tau)19.65MPa

tau = F / (n*pi*d^2/4).

Pin bending stress(sigma_b)104.8MPa

Simplified clevis model: M = F*s/4, sigma = M/S.

Eye bearing stress(p_e)55.56MPa

Fork bearing stress(p_f)34.72MPa

Required diameter, bending(d_b)16.97mm

Required diameter, shear(d_s)9.213mm

Method notes 3 notes

The bending check treats the pin as a simply supported beam over the bearing-center span with a central load. Real bearing pressure is distributed, so this is a conservative first-pass model only.
Bearing checks use projected area d*t. Fork bearing assumes each outside lug carries half the total load.
This does not check lug tear-out, net-section tension, pin-hole clearance, fatigue, cotter holes, retaining hardware, shock loads or code-specific resistance factors.