🔧 Assembly Design  ·  Thick Cylinder Theory

Press/Shrink Fit Interference Calculator

1
Units & Parameters
⚡ Results always in mm / MPa / Nm
2
Hole & Shaft Parameters
Assembly Analysis
Interference Pressure & Torque Capacity
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Contact Pressure P
0
MPa
Max Tangential Stress (Hub)
0
MPa
Max Tangential Stress (Shaft)
0
MPa
Torque Transmission Capacity
0
Nm
Axial Force Capacity
0
kN
Hub Expansion ΔDₒ
0
μm
Shaft Compression ΔDᵢ
0
μm
📐 Thick Cylinder Theory (Lame's Equations): P = δ / [D × (k₁/E₁ + k₂/E₂)]
k₁ = (D²+Dᵢ²)/(D²-Dᵢ²) - ν₁ (solid shaft: Dᵢ=0 → k₁ = 1-ν₁)
k₂ = (Dₒ²+D²)/(Dₒ²-D²) + ν₂Torque: T = π μ P D² L / 2 • Assumes L=2D (standard hub length)

Press fit and shrink fit assemblies rely on elastic deformation to create interference pressure between mating components. Using Lame's thick cylinder equations, this calculator determines the contact pressure, resulting stresses, and torque/axial load capacity.

Key considerations: Maximum pressure limited by material yield strength (typically 0.6 × σ_y). For solid shafts, set inner diameter to zero. Assembly methods: press fitting or thermal expansion (shrink fitting).

— Vaibhav Dhokpande, Developer · TaskJunction