The equations are called Lame’s equations.
Here’s an online calculator:
Under interference fits. You have to log in to be able to change the pin diameter.
Alternatively desertfox looked up the equations, so you can roll your own:
Here are the formulas you need:
- f=friction coefficient
- Pc=contact pressure between the two members
- d= nominal shaft dia
- L=length of external member.
- Pa= axial force required to interference fit
To calculate Pc for a given interference use the formula:
- x = total interference
- Dc=dia of shaft
- Di = inner dia of shaft(this is zero for solid shaft)
- Do= outside dia of collar
- Uo=poissons ratio for outer member
- Ui=poissons ratio for inner member
- Eo=modulus of elasticity for outer member
- Ei=modulus of elasticity for inner member
[This formula for Pc will simplify if the materials are the same.]