Interference fits - An Overview

A interference fit is a method of fitment in which the internal dimension of the component to be fitted is larger than the external dimension of the component on which the fitment is to be made. That is, the shaft is larger than the hole.   Interference fits are also called press fit, friction fit or shrink fit.

Examples of interference fits are the fitment of a wheel on an axle, the fitment of a vibration damper on the crankshaft, etc

Interference fits can be done using methods such as by the application of huge amounts of force by hydraulic means, by heating the components such that it expands and allows the smaller part to enter. 

Cooling the smaller part with liquid nitrogen or solid carbondioxide is also one method.  The part contract which makes it to fit the other component. 

Inteference fits provide excellent grip and are very reliable.