Press Fits - quick calculator

The equations are called Lame's equations.

Here's an online calculator

http://www.tribology-abc.com

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:-



Pa= f*3.142*d*L*Pc

where 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:-

Pc=x/[Dc*[((Dc^2+Di^2)/(Ei(Dc^2-Di^2))+((Do^2+Dc^2)/(Eo*(Do^2-Dc^2))-((Ui/Ei)+Ui/Eo))]

where 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.