Bearing stuck on shaft

[nh3simman]

You have a bearing stuck on a shaft.
http://i14.tinypic.com/4hmpxmd.png
By heating the bearing, we know that the metal will expand.

Does the hole get bigger, smaller or stay the same?

[Toolman]

Its a trick question I reckon , metal expands when you heat it this helps to remove tight fitting bearings , thats the simple answer

[nh3simman]

Its a trick question I reckon ,

Come on Toolman, don't be so suspicious.

[Peter_1]

It becomes wider.
SKF Bearings (Sweden) sells a special device - I used it several times - where you put your bearing over an induction coil and energise then that coil so that the bearing heats up and fits over the ax.
http://www.acorn-ind.co.uk/products/prind.htm
http://www.skf.com/images/induction-heater.jpg

[nh3simman]

It becomes wider.
SKF Bearings (Sweden) sells a special device - I used it several times - where you put your bearing over an induction coil and energise then that coil so that the bearing heats up and fits over the ax.
http://www.acorn-ind.co.uk/products/prind.htm

Thanks for the link, thats quite useful.
Better than percussion therapy would you say?

[Paulajayne]

It gets bigger depending upon its coefficient of linear expansion and temperature increase.

Whilst it will expand towards its virtual centre it will also expand in circumference which will more than offset this movement towards its centre and so its internal diameter will increase.

Paula

[Argus]

Whilst it will expand towards its virtual centre it will also expand in circumference which will more than offset this movement towards its centre and so its internal diameter will increase.

Paula

That's about the size of it.

.

[Cofreth]

Another way you may soak it into hot boiling compressor oil.

[Peter_1]

or freeze the axe if your bearing isn't allowed to get very hot. Soem use the same device as they use to make an ice stops on water lines.
http://www.rothenberger-tool-uk-sales-and-hire.co.uk/19_files/R62205.jpg