Can I use a deep fat fryer to heat bearings to fit to a shaft?

This deep fat fryer will heat to 400deg. Do I use a veg oil,   or  compressor oil

  .... someone told me this once, I don't know what oil to use that won't burn easily.
A one time job  just don't want to buy a bearing heater
 These bearings are 3" OD and go in a large compressor doing a rebuild on the low cost mode...

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Hey i got an idea Get a Propane Torch it's safer and you have less of a chance of burning your house down or get an oxygen acetylene torch ignite both gases but don't start cutting it all you are doing is using the combustion to heat the metal
tewharau7 years ago
 Man, I hope your dinner guests don't read your question.  This fried chicken tastes funny....have you been rebuilding compressors again?
dataphool7 years ago
I have never done this, but I read about the technique.  Place the automotive bearing packed with grease on top of an ordinary 60 Watt incandescent bulb.  Leave for some time, I would think  30-45 minutes, and it should slip on the shaft.

Maybe stick it in the oven, set to 400 F, 



today at work I actually had to heat a bearing and cool a shaft.   I just went for the shaft into the freezer and heated the bearing with a torch.  

Now with you saying they go inside a compressor, i'm guessing they are not sealed, so heating with a torch, you shoudln't have to worry about melting seals or anything.  

But I guess if you want to heat then in a fryer you could.   You just have to make sure the bearing is clean, or put it in before the oil gets hot.  I would use compressor oil  (SAE 30 non detegent) to avoid contamination
There's also the other way round, cryocooling the shaft - if you're lucky, a big welding shop will have liquid nitrogen - when I need to fit bearings, I can usually bum a vacuum flask worth of LN to do a few parts. Liquid Argon would work too, but that's a lot more expensive.
lemonie7 years ago
Not a good idea. What sort of bearings are they specifically?

L
Prfesser7 years ago
Do NOT use vegetable oil.  It can polymerize to some extent, forming a varnish-like material that will make bearings unhappy.  (See the gummy coating on the edge of the fryer?)

Virtually any oil that is heated to 400 F can burn, apart from some very expensive fluorinated oils.  Two good questions to investigate: do you really need to heat the oil to 400 F, or will a lower temperature do the job?  And can you cool the shaft and heat the bearing simultaneously, rather than just heating the bearing?