Black Country Cryogenics can provide all equipment needed to achieve your desired shrink, including custom made boxes and immersion tanks


Shrink Fitting is a method used to insert a pin or bushing into a housing or other assembly requiring an extremely tight tolerance fit.


It can be used as an alternative to conventional press fitting or more likely to permit a mechanical fit that otherwise could not be accomplished via the mechanical force of press fitting.

 

In Application

 

The insert is cooled through exposure to Liquid Nitrogen in order to reduce its size through contraction usually associated with reduced temperatures.

 

Why Shrink Fitting.

 

  •  Shrink Fitting can be performed in minutes.
  •  Shrink Fitting provides a precision fit.
  •  Shrink Fitting will not damage ferrous and non  ferrous metals.
  •  Heating components can distort or damage.
  •  Heating components may take hours to      achieve the necessary expansion.
  •  After shrinking components reach ambient      temperatures more rapidly than heated.
  •  Heating may introduce an imprecise fit    between components.
  • Shrink fitting maintains the interference fit for which the components were designed.
  • No discolouration of metal after shrink fitting.
  • Shrink fitting can illiminate the need for key ways or other fixing methods.
  • Shrink fitting can also be used to dismantle assemblies.

  Advantages Over Heat Expansion.

 

  • A 4" diameter shaft can be shrunk by 6.o thou in 20    Min's, smaller components such as valve guide stake  only a matter seconds.
  • No time is lost with oil baths or furnaces as the components are immersed in a bath of Liquid Nitrogen and monitored .
  • The shrink fitted treated component is easier to work with than the heated one therefore reducing handling time.