Press Fit Rechner — Formel
## Press Fit (Interference Fit) Analysis
A press fit creates a joint by assembling a slightly oversized shaft into a slightly undersized hole.
### Simplified Formula (solid shaft, same material)
**p = delta E (1 - (d/D)^2) / d**
where delta is the radial interference (diametral/2), d is shaft diameter, D is hub OD, and E is the elastic modulus.
### Assembly Force
**F = pi d L p mu**
where L is the engagement length and mu is the friction coefficient.
A press fit creates a joint by assembling a slightly oversized shaft into a slightly undersized hole.
### Simplified Formula (solid shaft, same material)
**p = delta E (1 - (d/D)^2) / d**
where delta is the radial interference (diametral/2), d is shaft diameter, D is hub OD, and E is the elastic modulus.
### Assembly Force
**F = pi d L p mu**
where L is the engagement length and mu is the friction coefficient.
Lösungsbeispiel
A 50 mm shaft pressed into a hub (OD=100 mm) with 0.05 mm diametral interference, 40 mm long, steel.
- k = (50/100)^2 = 0.25
- 1/(1-0.25) = 1.333
- p = 0.05 x 200,000 / (50 x 1.333) = 10,000 / 66.67 = 150 MPa
- F = pi x 50 x 40 x 150 x 0.15 / 1000 = 141.4 kN