Parameters
Contact diameter d50.0 mm
Hub outer diam. do100.0 mm
Shaft bore di (solid=0)0.0 mm
Engagement length L50.0 mm
Diametral interference δ0.050 mm
Hub modulus Eh206 GPa
Hub Poisson's ratio νh0.30
Shaft modulus Es206 GPa
Shaft Poisson's ratio νs0.30
Friction coefficient μ0.12
Yield strength Sy250 MPa
Lamé Equation
$$p = \frac{\delta/d}{\dfrac{1}{E_h}\!\left(\dfrac{d_o^2+d^2}{d_o^2-d^2}+\nu_h\right)+\dfrac{1}{E_s}\!\left(\dfrac{d^2+d_i^2}{d^2-d_i^2}-\nu_s\right)}$$Assembly force: $F = \mu p \pi d L$
Torque capacity: $T = F \cdot d/2$
0.0 MPa
Contact Pressure p
0.0 kN
Assembly Force F
0.0 Nm
Torque Capacity
0.00
Safety Factor (hub)
Hub Stress Distribution
Interference vs Contact Pressure & Force
Hub Stress (Lamé)
Hoop stress: $\sigma_\theta(r) = p\dfrac{(d/2)^2}{(d_o/2)^2-(d/2)^2}\!\left(1+\dfrac{(d_o/2)^2}{r^2}\right)$
Radial stress: $\sigma_r(r) = p\dfrac{(d/2)^2}{(d_o/2)^2-(d/2)^2}\!\left(1-\dfrac{(d_o/2)^2}{r^2}\right)$
Maximum at inner bore $r = d/2$.
Engineering note: ISO tolerance fits (H/s, H/r): typical δ/d ≈ 0.001–0.003. Dry steel-steel friction μ ≈ 0.12–0.15. Design for transmitted torque with safety factor 1.5–2.0. For large diameters use oil-injection assembly to protect bore surface.