PDA

View Full Version : Removing Bearing Races



BWB
01-15-2009, 01:11 PM
Have a machine spindle with a tapered roller bearing in each end. Need to replace the bearings and races. Both races are truly blind: there is no purchase at all for a drift or anything else to get at their backsides.
What is the best method for removing these?
I suppose I could TIG a bridge to them, bit I'm reluctant to do it if there's a better way. Any help is much appreciated.

VicM
01-15-2009, 01:19 PM
A crude and messy method we used on commercial mower rollers was to run a bead on the race with the stick welder. The race would ( usually) shrink enough to fall out. The spatter was a problem.

radioman
01-15-2009, 01:19 PM
I have been working in heavy industry, and have come up with this problem many times. The best method to use is to run a couple of heavy beads of weld around the inside race of the bearing. When every things cool, the bearing race is smaller 2 - 3 thou and easier to remove. Take your time and be safe.

Dennis

Peter.
01-15-2009, 01:26 PM
http://www.metalworking.com/Dropbox/blind_bearing_removal.txt
http://www.metalworking.com/Dropbox/blind_bearing_removal_1.jpg
http://www.metalworking.com/Dropbox/blind_bearing_removal_2.jpg
http://www.metalworking.com/Dropbox/blind_bearing_removal_3.jpg

Evan
01-15-2009, 04:16 PM
Freeze them with liquid nitrogen and give them a tap with a center punch. They will shatter like glass.

Spin Doctor
01-15-2009, 04:23 PM
Welding a chevron bead around the inside of the race is probably the best method if you can control the splatter. Welding a bar across the racxes so you can knock them out does work. But I have seen the welds break at least half the time. Also if you have a slide hammer weld a couple of screws to the races (threaded end out) and use the slide hammer to tap it out. Another option with screws is to have a bridge above the surface of the housing and draw the race out with a couple of nuts. Liquid nitrogen is a little scarce at the moment, although it is a little chilly out right now.

Evan
01-15-2009, 04:32 PM
Liquid nitrogen is easy to find. Just phone any doctor's clinic and ask which welding supply they get theirs from. Take a stainless steel thermos and have it filled, maybe even for free.

aboard_epsilon
01-15-2009, 04:38 PM
I don't know what the thing looks like

but try this first........put a block of metal across ..whatever houses them .. on opposite end, I'm assuming they are in a tube.........keep metal held against it hard ...tap on metal with hammer as hard as you can without damaging anything.

the shock waves will make the bearing climb out.

i have done this ..and it does work ..........well it worked on the thing i was working on.........which was an engraver spindle

all the best.mark

Davidhcnc
01-15-2009, 04:41 PM
Warm the whole thing in an oven..don't go mad...and it might fall out in the oven.


If not a squirt with a freeze spray and it will probably fall out ( after oven).


If not drill two 3/16" holes in the casting:eek: and knock it out after oven.

BWB
01-15-2009, 05:16 PM
Thanks everyone. I'll try running a bead all around with my TIG. Spatter won't be a problem with that.
If that doesn't work, I'll try the liquid nitrogen caper. Frankly even the thought of getting something for nothing from a doctor tempts me to try it.

Evan
01-15-2009, 07:13 PM
Once you have welded on the races they probably won't shatter since they will be at least partly annealed.