Machine Design

Shaft Diameter Simulator

Analyze and determine the minimum safe diameter of rotating shafts subjected to combined bending and torsional loadings. Leverage the ASME B10.11 design formulas.

Code standard

ASME Code

Combined Load

Mesh

21 nodes

Torsional sweep

Output

CSV

Export ready

Parameters

Shaft Material

Allow. Shear Stress (τ)60 MPa

10250

Torsional Load (Mt)1000 N·m

05000

Bending Load (Mb)500 N·m

05000

Bending Shock Factor (Kb)1.50

Torsion Shock Factor (Kt)1.00

Animated torsion sweep

ASME Code Combined Stress

Equivalent Torque

T_e = \sqrt{(K_b \cdot M_b)^2 + (K_t \cdot M_t)^2}

Equivalent Bending Moment

M_e = \frac{1}{2} \left( K_b \cdot M_b + T_e \right)

Safe Shaft Diameter

d = \left( \frac{16 \cdot T_e}{\pi \cdot \tau_{allow}} \right)^{1/3}

Max Shear Stress

\tau_{max} = \frac{16 \cdot T_e}{\pi \cdot d^3}

Equivalent torque is calculated as 1250.0 N·m based on Kb = 1.5 and Kt = 1.0.

For a safe shear limit of 60 MPa, the minimum diameter is 47.34 mm.

Shaft Physical Deflection & Loadings

Required Diameter

47.34mm

Equivalent Torque (Te)

1250.0N·m

Eq. Bending (Me)

1000.0N·m

Max Shear Stress

60.0MPa

Required Diameter vs. Applied Torsion

Torsional Load Step Analysis

Torsion Moment Mt (N·m)	Equivalent Torque Te (N·m)	Required Shaft Dia (mm)
0	750.0	39.93
500	901.4	42.45
1000	1250.0	47.34
1500	1677.1	52.21
2000	2136.0	56.60
2500	2610.1	60.51
3000	3092.3	64.03
3500	3579.5	67.23
4000	4069.7	70.17
4500	4562.1	72.89
5000	5055.9	75.43