About Shrink Fitting
When an interference fit is required, the traditional way of fitting a component into another is either the force fit method or to expand the outer component with heat. Both these methods have disadvantages in that the former can lead to mechanical damage between the two faces and the latter can cause local damage or stress due to uneven or poor heating procedures, as well as the practicalities of heating large frames or housings.
For each application using the traditional methods, liquid nitrogen shrink fitting can invariably be used as an alternative. Using this method the inner component is immersed in a liquid nitrogen bath at -196°C.
Liquid nitrogen shrink fitting is one of the safest methods of assembly as it is inert and therefore quite safe to use in a workshop situation provided there is adequate ventilation.
The components will suffer no damage, as liquid nitrogen has no permanent effect on ferrous or non-ferrous metals; certain austenitic irons excepted.
PLEASE DIRECT ANY ENQUIRIES TO OUR SALES OR TECHNICAL DEPARTMENTS
Download our Brochure here: Shrink Fitting Brochure
Sequence A
This picture shows the end of the shaft immersed in the Liquid Nitrogen cooling tank where it is allowed to cool down to -196°C.
Sequence B
The shaft into which the bearing sleeve has already been fitted (the sleeve is held in place with a retaining bolt) is offered into the drive coupling.
Sequence C
The shaft having been shrunk to the predetermined dimension, dropped to its required position in the new coupling (note the sleeve retaining bolt) and is allowed to warm up to room temperature normally.
