Pillow Block Bearing

[cyro]

I was asked today to look at a 40 year old kitchen exhaust fan making noise.

Previous men have replaced every part but not the pillow block bearing that is 24" on the shaft.

I have never repaced a bearing this far on a shaft before.

Has anyone done this and how?

[dandyme]

Be prepared to cut it off with a grinder.

Use a thin wheel instead of the standard grinding wheel

[selfemployed]

Before you cut them off, which you may have to. Spray the shaft with wd40 and clean with sand cloth while it's running. Tap bearing down on shaft to clean under where it sat on shaft and then maybe you can move it back up and off the shaft. P. S. File the set screw markes off the shaft too. Just takes time.

[Dad]

Like a convection oven squirrel cage.....

Heat the shaft and bearing with a torch. Douse with water. Heat again and douse. Spray with Kroil or WD40 for lubrication. The difference in metal density will cause the bearing and shaft to expand and contract at different rates. This will cause the bearing to break free from the shaft for easy replacement....



edit.... if the shaft and bearing smoke when you spray it is too hot, wait until it cools

[Edited by Lusker on 10-24-2006 at 10:49 PM]

[Special-K]

Use sand cloth and a file if needed to polish the shaft from the end, down to the bearing, and 2" below the bearing. Oil it and drive the bearing down on the spot you cleaned below it. Clean the spot where the bearing was and file any rough spots. Oil again and slide it right off.

It's all about preperation.

[cyro]

I thought Sanding the shaft while running was right. and I will cut it off I have the thin cutting wheels(love those)

But how do you slide the new block down 24", Use a pipe that is longer then 24" and it just a bit larger then the shaft which is 1 7/16" ?

[hvac wiz 79]

grind it .. split it. & break that thing off .. its junk anyway ... works for me

[rob in lvnev]

with a new pillow block you will have to clean the entir shaft if you are using the same shaft and lub the heck out of it and tap it to where you want it, hope this helps

[cyro]

I will have to do this on thanksgiving day, rain or shine, This is for a college and this is the only day the kitchen is not cooking till xmas. to make matters worse it's the only hood fan they have, every hood is connected to this one fan. How stupid is that but it is 45 years old.

I never have put a pillow block down a shaft 24" I have done pillows before but not 24" I will sand the shaft will running, oil good, cut the old ones but how do you push it 24" down the shaft???????, a block of wood with a hole in it?????? Hollow pipe?????

2 in house guys replaced the easy bearing on the end of the shaft 3 months ago but left the 24" hard bearing on with metal shavings pooring out . It took the two all day for the one easy bearing so now they will not trust them for the hard one to do so I get to do it on Thansgiving!

Just needed as many suggestions so I will be able to get home quick

[crackertech]

if you have shavings pouring down then you might need a new shaft also.

[selfemployed]

Go do the sanding of the shaft and put some rust breaker or wd on screws, bearing lock collar set screws ect. ahead of time.

[oogene]

as a truck/ reefer mechanic; I did what lusker says except I heated the parts and cooled them with panther piss once or twice- worked almost every time !!!or jar stuff loose with a smack of a punch and hammer

[jkochan]

Worked on a couple of these. Sand and CLEAN the shaft VERY WELL and the new bearing should slide right down the shaft. If you oil the shaft lightly it will help. Too much oil on the shaft will cause a suction seal and make the bearng harder to move. If the shaft is damaged it should be replaced or repaired. I worked on an air handler at a large church that had the brick and stone work put up AFTER the equipment went in .... no way to extract the 10' long shaft that was damaged by a spun bearing. Welding and grinding were not an option. Found an epoxy product from Belzona Moutain States (http://www.belzonamsd.com) which allowed me to repair the shaft in place. I have used this company's products for years, but this was new to me. I rebuilt the shaft with epoxy and it has now been in service with the new bearing for 5 years. Hope this helps.

[cyro]

Well I was told the in house guys would handle the job but now today it's back to me again.

I spoke to Bearing Corp today because I wanted a beefy bearing. They taught me allot about bearings in a short period on the phone. I thought I knew allot, boy was I wrong. Great people over there.

Bearings are coming in on Monday, 10 h.p. motor on a 30" dia fan. There are no labels. cfm I fiqure is around 10000-12000cfm.

[fastfred]

Originally posted by cyro
Well I was told the in house guys would handle the job but now today it's back to me again.

I spoke to Bearing Corp today because I wanted a beefy bearing. They taught me allot about bearings in a short period on the phone. I thought I knew allot, boy was I wrong. Great people over there.

Bearings are coming in on Monday, 10 h.p. motor on a 30" dia fan. There are no labels. cfm I fiqure is around 10000-12000cfm.

If you use the grinder ( SPARKS !!!) have a fire extinguisher ready.

[stormrider]

By the time you get the saft out of the blower it's going to be out of balanced.

Replace it!!

Grainger has alot of fans in stock.

[markwolf]

The most cost effictive way would be to cut the old shaft out of the way & replace the shaft & bearing assembly.Or you could reuse the old shaft only to find it is slightly out of balance after the new bearing is installed & probably was the cause of the bearing failure to begin with upsetting the customer & you.

[cyro]

The inhouse guys took the bearings and where suppose to do it at 5a.m. Friday.

I don't know yet if they ran into any problems, I hope all went smooth for It will just be dumped back to me.

[propmanage]

Have done about fifty of these on large units and I no longer like them. You have received good advice. Best thing is to plan on several hours of cleaning so if you can spry it down in advance do it. Bring lots of rags and sand cloth. Sand while you can still spin the shaft. If you can't move the bearing after cleaning and tapping and heating you will need to cut it off, then clean again. After all this the new one will go on or you will sand and clean again until it does.
Good luck it will be ok

[cyro]

After all said and done they have decided to install a whole new unit.

Hope to do it during Thansgiving shut down for saftey concerns with all the students walking around.