How do I remove this small bearing? And the one behind it.

[pgrbffParticipant @pgrbff]

[pgrbffParticipant @pgrbff]

This bearing is 30mm diameter with a 10mm hole, there is another behind it.

Is it possible to remove it without damage?

[Nigel Graham 2Participant @nigelgraham2]

I take it the housing is blind.

One method is hydraulic: pack the cavity with grease, insert a length of bar that is a close sliding fit the bore, and strike the outer end of the bar with a hammer, or push it down with a press. The cavity does need to be as full of grease as possible..

The problem here though is the risk of damaging the rear bearing.

[Nick WheelerParticipant @nickwheeler]

Expanding mandrel(a rawlbolt) and slide hammer for the first; hammer and drift for the second.

Or you could buy a bearing puller that works the same way.

[mechman48Participant @mechman48]

+1 ..posted before I could finish typing.

George.

[David George 1Participant @davidgeorge1]

Hi pgrbff what is the casting part off and is the hole blind or is there a through hole from the back. A couple of diferent angle pictures may help.

David

[pgrbffParticipant @pgrbff]

It's blind, Only way in is what you see. Aluminium casting. The hole is a little bit deeper than the 2 stacked bearings and the top bearing appears to have been put in slightly off square.

[Howard LewisParticipant @howardlewis46836]

If the grease method does not work, it will be necessary to destroy the outer bearing.

Make up a puller which will drag out the inner race, This will liberate the actual race. Then the "puller" can be set to grip the outer race and extract that.

Then try the grease method on the inner bearing. The closer the fit of the "plunger" to the inner race, the greater the prospects of success. The grease needs to as thick as possible, so that the minimum leaks through the bearings.j

Howard

[Clive FosterParticipant @clivefoster55965]

Another vote for a Rawlstud or similar concrete anchor as an expanding mandrel.

I have a small collection with intermediate aluminium sleeves kept for such purposes. For best grip it's important that the actual expander cone sits mostly inside the bearing. Any projection should be to the rear. Hence the collection of made for a job sleeves to get the fit right. Alloy sleeves, suitably slit for expansion, has a better grip on the inside of the bearing than the steel Rawlstud expander.

Using a stud type anchor lets you draw the bearing out with a second nut on the extended portion of the stud working through a tube and thick washer.

Well worth warming things up if its feels tighter than you'd like when trying to draw the bearing off. Especially if it is a bit skew-wiff.

Clive

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Clive Foster on 09/04/2021 09:09:30:

[…]

Well worth warming things up if its feels tighter than you'd like when trying to draw the bearing off

.

Especially as the housing is Aluminium

Differential expansion can make things much easier.

MichaelG.

Edited By Michael Gilligan on 09/04/2021 09:19:01

[J HancockParticipant @jhancock95746]

Last resort.

8mm bolt with head machined to just under 10mm and knife edge thickness to get under lower edge of that bearing.

Force it off-centre with a wedge, bridge the bearing with a plate , support either side, nut on , pull bearing out.

[pgrbffParticipant @pgrbff]

Posted by Nicholas Wheeler 1 on 09/04/2021 08:42:15:

Expanding mandrel(a rawlbolt) and slide hammer for the first; hammer and drift for the second.

Or you could buy a bearing puller that works the same way.

I'm not sure there is enough room between the stacked bearings.

What is the easiest destructive way to remove them?

[DalboyParticipant @dalboy]

How about heating the casing and see if it will come out easy either drop out or take less effort for it to be pulled or hydraulic out

[pgrbffParticipant @pgrbff]

Posted by Derek Lane on 09/04/2021 10:22:11:

How about heating the casing and see if it will come out easy either drop out or take less effort for it to be pulled or hydraulic out

I'll try, but there are 2 in there. I think the deeper one might be more difficult.

[Nick WheelerParticipant @nickwheeler]

Posted by pgrbff on 09/04/2021 10:15:50:

Posted by Nicholas Wheeler 1 on 09/04/2021 08:42:15:

Expanding mandrel(a rawlbolt) and slide hammer for the first; hammer and drift for the second.

Or you could buy a bearing puller that works the same way.

I'm not sure there is enough room between the stacked bearings.

What is the easiest destructive way to remove them?

Why would this method need space between the bearings? The expanding mandrel grips the inner race of the first bearing. It would work well with the spacer and threaded bar mentioned in other posts, which given the lack of support on the housing is probably a better idea.

I hadn't read your first post properly to realise they're in a blind hole, so would use the same technique on the lower bearing.

If the housing is aluminium, then I'd set up the puller and give the housing a lick of heat to make the job go better.

I've never had any luck extracting bearings with the grease method which just seems to make a mess.

[not done it yetParticipant @notdoneityet]

I would be replacing those bearings, so damaging them at removal would not be an issue for me.

Damp doughy bread is far better than grease, as a hydraulic medium. I expect they may well almost drop out with adequate heating. Try in the oven, if you are worried about melting the casting.

The rawl bolt and slide hammer usually works OK.

Edited By not done it yet on 09/04/2021 10:54:35

[John BaronParticipant @johnbaron31275]

Hi Guys,

It won't be the first time that I have made a mandrel to remove bearings in blind bores. First most bearings that I've come across tend to have a slight chamfer on the edges. So I've turned suitable piece of rod to be a good fit in the bore, drilled down the centre and split the end with a hacksaw, then clamped the split in a vise and threaded it. Using a suitable bolt threaded into it the split is forced apart and will grip the bearing bore very securely. You can then use any convenient method to remove the bearing such as a hooked slide hammer.

[pgrbffParticipant @pgrbff]

Posted by Nicholas Wheeler 1 on 09/04/2021 10:38:05:

Posted by pgrbff on 09/04/2021 10:15:50:

Posted by Nicholas Wheeler 1 on 09/04/2021 08:42:15:

Expanding mandrel(a rawlbolt) and slide hammer for the first; hammer and drift for the second.

Or you could buy a bearing puller that works the same way.

I'm not sure there is enough room between the stacked bearings.

What is the easiest destructive way to remove them?

Why would this method need space between the bearings? The expanding mandrel grips the inner race of the first bearing. It would work well with the spacer and threaded bar mentioned in other posts, which given the lack of support on the housing is probably a better idea.

I hadn't read your first post properly to realise they're in a blind hole, so would use the same technique on the lower bearing.

If the housing is aluminium, then I'd set up the puller and give the housing a lick of heat to make the job go better.

I've never had any luck extracting bearings with the grease method which just seems to make a mess.

All of the tools/mandrels I have seen are wider at the end and expand beyond the hole in the bearing, not in the hole itself.

[Nicholas FarrParticipant @nicholasfarr14254]

Hi pgrbff, you can get proper extractors for removing bearings in a blind hole, but are a bit expensive for an occasional job. Your local garage or an engineer firm may have such things. If you go down the root of destroying the bearing, you need to be careful you don't fracture the housing, as they don't look to be in a stage where they are ready to collapse and they maybe small, but they will be tough. Heating the housing would be a next good method to use, failing that, and assuming your intent is to replace them, tac welding a piece of studding or a bolt with the head cut off in the bearing bore and drawing the bearings out with a tube a little larger than the outside dimension of the bearing and long enough to accommodate the bearing width, with a plate and nut on the studding.

Regards Nick.

Edited By Nicholas Farr on 09/04/2021 12:59:22

[Clive FosterParticipant @clivefoster55965]

pgrbff

The rawlstud (concrete anchor) based extractors I make when needed don't need any space behind the bearing to work pretty well. Simply expanding into the inner bore of a ball race generally provides enough grip to pull the bearing out. Especially if an alloy intermediate sleeve is used.

If you can't get enough grip odds are the bearing was fitted with the housing significantly heated so pulling out cold will likely damage or scrap the housing.

Clive

[Ian ParkinParticipant @ianparkin39383]

I would drill 2 small holes behind the bearings in the casting at centres of 28mm so a pin punch can knock them out together using the outer races

[Grindstone CowboyParticipant @grindstonecowboy]

I recall seeing somewhere – possibly on the SKF site – a bearing puller that has thin legs with shaped ends that are designed to fit between the balls and then twist to lock into the inner and outer races. More than likely horribly expensive, but an interesting idea.

Rob

[Roy VaughnParticipant @royvaughn26060]

Heat is usually the answer for bearings in aluminium housings. Get the housing good and hot (a heat gun should do) and the bearings may well drop out. If not, try again with a piece of wood wedged into each inner race in turn so you can give them a bit of help. If the wood won't grip enough then make an expanding mandrel. Roy

[old martParticipant @oldmart]

I'm with Alan for a couple of small holes. The bearings are likely to be cheap to replace so damaging the old ones won't matter much. Try heat first, you might be lucky.

[pgrbffParticipant @pgrbff]

Posted by Grindstone Cowboy on 09/04/2021 13:25:18:

I recall seeing somewhere – possibly on the SKF site – a bearing puller that has thin legs with shaped ends that are designed to fit between the balls and then twist to lock into the inner and outer races. More than likely horribly expensive, but an interesting idea.

Rob

Trouble is that I will probably not have to do it again and it will be very expensive.

[Author]

Posts