The answer to this month’s trouble shooter is provided by Schaeffler (UK) Ltd. Q: For large-size rolling bearings with outside diameters above 1500mm, what type of heating methods are available for mounting/dismounting and which is the most suitable?
Published: 03 March, 2016
In order to correctly mount or dismount rolling bearings, it is usually necessary to heat the bearing first. Heating methods include thermal mounting tools (heating plates), induction heating, mounting paste and heating rings. Selecting the most appropriate method ensures the bearings are mounted and removed easily and quickly, in a safe, reliable manner, without causing damage to the bearings.
When mounting large-size rolling bearings with outside diameters of 1500mm or above, several heating methods are available:
Using an oil bath requires a large enough bath for the bearings to be heated in. If one does not exist, it will have to constructed, which is time consuming and costly.
Uniform heating of the oil is a problem and there will be difficulties in handling a large, oily bearing at 120oC.
Gas flame burners require only a couple of gas cylinders and a burner. However, this method needs a highly skilled operator(s) to evenly heat up the bearing with a soft flame, which may tie up 3 or 4 people for up to four hours per bearing.
Fixed or mobile induction heaters are faster, cleaner and more suitable for batch heating. Heat is transferred directly and uniformly to the bearing.
For large-size rolling bearings, flexible induction heating is the most suitable method. The heating cable is flexible and so can be placed in and around the bearing or in areas that would normally be inaccessible. Heating time is only 1-2 hours.