Shaft Bending, Torsion & Deflection Calculator

Check an existing round shaft or find the diameter required by combined-load method and an elastic deflection limit.

Total force acting across the belt width.
Use the actual bearing span, not only belt width.
Supports are assumed equally spaced and radial only; full shaft torque is retained.
Sprockets, fillers, belt and product near the shaft. Shaft mass is calculated automatically.

Shaft

Results

Bulletin required outside diameter
Deflection required outside diameter
Governing recommended diameter
Support arrangement
Effective span between supports
Resultant load per span
Total shaft mass
Total vertical weight force R
Resultant distributed shaft load Wr
Torque
Maximum bending moment
Calculated maximum deflection
Deflection ratio
Suggested intermediate supports

Method and limitations

With intermediate supports, the full shaft is divided into equal spans, the distributed radial load is divided among those spans, bending is calculated for the most heavily loaded span, and full shaft torque is retained. Deflection is calculated separately for a simply supported span.

The calculator is intended for preliminary engineering checks. It does not replace a detailed shaft design including stress concentrations, fatigue, bearing reactions, critical speed, key design, local sprocket loads, shaft shoulders, corrosion allowance, thermal effects or verification by the equipment manufacturer.