Bearing removal

[mgarym]

At the end of silage cutting this year there was a noise from the harvester
so before putting it away for the winter I decided to strip it down and see what the problem was.As it turned out a bearing on the knife cylinder had collapsed.
I have all the parts removed around it but the inner race is still stuck on the shaft, i cant get a grinder in to cut it and there is nowhere to hook the legs of the puller.i was thinking of welding something onto the bearing to hook the
puller to, is there any special rod or prep i should do to welld to bearing?

 

[clem dog]

Weld on a piece of flat with a threaded hole in the middle across the race and use a long bolt to push the race out. The heat from the welding may help to release the bearing because as it cools it will contract and slacken the race.
Or do you have oxy propane set up? If you are carefull you could but the race with this.
Hth
Clem


Edit Just saw your bearing is stuck on the shaft. Make a U shaped piece with said threaded hole on the top and weld the two side pieces on to the bearing race. Then use a bolt to push from the ond of the shaft. If it pulls sideways then use two more pieces on the side to enable it to pull straight. I have had success using ordinary rods in the past to do this. Opposite applies in this case. Do it while it is still warm and the race has expanded around the shaft.

 

[piman]

Hello Mgarym,

as long as you can get access to get a good bead I wouldn't worry about prep.

Ideally if you can weld two lengths of screwed rod, one each side to connect to your bearing puller then do that Set it all up with the puller in place and some tape to hold the rods to the inner race, weld both then tighten the puller to take advantage of the hot race before the heat soaks to the shaft?

I think what Clem says works for an outer race stuck in the housing. Usually just a bead of weld round the race track shrinks the bearing outer when it cools making it easier to remove.

Alec

 

[mgarym]

the shaft sticks out about 2 inches through the bearing so i would need to weld pieces out parallel to the shaft and then across, will the welds crack due to welding mild steel to the hard bearing material ?
I'm not sure a bolt will move it as the shaft is about 2 " dia

 

[clem dog]

Beat me to it Piman. I was editing as you posted!

 

[mgarym]

beat me too
thanks piman and clem i'l give that a go

 

[clem dog]

A bolt should work as it is, in essence, the same as a set of bearing pullers just home made. Or as Piman said, use your own pullers and put on something to yoke them to.

Clem

 

[gordon stephenson]

You could most likely get it off just by running a quick bead of weld round the outside of the bearing, or even quite a short run and pull it off easily with a pair of decent size "eagle beaks" etc once the inner race has expanded,It's only going to be a thou or two interferace so a short sharp dose of heat will do the trick,

 

[Justme]

You could most likely get it off just by running a quick bead of weld round the outside of the bearing, or even quite a short run and pull it off easily with a pair of decent size "eagle beaks" etc once the inner race has expanded,It's only going to be a thou or two interferace so a short sharp dose of heat will do the trick,

But let it cool slightly & it will be even tighter.

 

[brightspark]

But let it cool slightly & it will be even tighter.

steel on steel expands at the same rate so nothing to be gained anytnings worth a try mind

 

[piman]

Hello Brightspark,

"steel on steel expands at the same rate so nothing to be gained anytnings worth a try mind"

Yes, but the race will be hotter for a while, but the point about it being tighter when it cools is quite valid as the shrinking weld bead will tighten the race on the shaft. So if it doesn't come off with the first pull it will be harder to remove.

Alec

 

[mgarym]

I found an old inner race that was 6 or 8 mm bigger and cut a ring 10mm thick
welded it to the bearing and used 10 ton hydraulic pullers and some extra heat
and it eventually came off

thanks everyone

ps now to get the new bearing back on

 

[Pete.]

Hello Brightspark,

"steel on steel expands at the same rate so nothing to be gained anytnings worth a try mind"

Yes, but the race will be hotter for a while, but the point about it being tighter when it cools is quite valid as the shrinking weld bead will tighten the race on the shaft. So if it doesn't come off with the first pull it will be harder to remove.

Alec

Very true, because you can remove an outer race stuck in a housing by running a weld bead around the inside. When it cools it will fall right out.

 

[gordon stephenson]

steel on steel I quite agree, why do you think I said short sharp burst of heat, So that the race will expand before the shaft even sees any heat, Same as when you are burning collars etc from shafts, the thinner material heats far faster and does not have time to transfer the heat across the "break line" between the thinner and thicker material,All you oxy/acet men out there will have done this many times without any problems,

 

[brightspark]

steel on steel I quite agree, why do you think I said short sharp burst of heat, So that the race will expand before the shaft even sees any heat, Same as when you are burning collars etc from shafts, the thinner material heats far faster and does not have time to transfer the heat across the "break line" between the thinner and thicker material,All you oxy/acet men out there will have done this many times without any problems,

your right there gordon ive done it myself with oxy u just have to heat outer ring up fast and remove quickly