We have a bearing thats nearly roasted in the natural gas furnace. Its a
NMB 608Z, near as I can figure this is the same as a 8x22x7mm bearing. Its
for the exhaust fan near a lot of heat. I found tons of inline skate
bearings that are 8x22x7mm, now the big question is does anybody have links
or info regarding whether I should go ceramic,stainless, or just the
cheapest steel ones I can get. after application data ? so I can wrap my
head around this stuff. Thanks.

Mike

On Tue, 23 Oct 2007 04:04:49 GMT, "Michael S"
wrote:

We have a bearing thats nearly roasted in the natural gas furnace. Its a
NMB 608Z, near as I can figure this is the same as a 8x22x7mm bearing. Its
for the exhaust fan near a lot of heat. I found tons of inline skate
bearings that are 8x22x7mm, now the big question is does anybody have links
or info regarding whether I should go ceramic,stainless, or just the
cheapest steel ones I can get. after application data ? so I can wrap my
head around this stuff. Thanks.

Mike

Can you define "roasted"? Is the grease hardened? Steel turned blue?
How long did it last? Do you know the temp it's seeing? May be as
simple as going to a higher temp grease but normally that will require
a change in the bearing as well. Temp stabilized bearings are
available and cheaper than ceramic but it depends on the conditions it
is seeing.

no colour change in it and there was no grease left in it. balls and race
are quite sloppy and grindy. guess roasted wasn't quite the term to use but
the sheet metal next to where the bearing is mounted is a lot hotter than I
can touch. crammed some grease in it last night and it ran quiet for about
2 minutes, but guess a high temp grease would be a good thing. of the
beaings I have found looking around so far a 608zz w/ steel shields is whats
in the furnace. to bad its $8 shipping for $2 and change for 4 bearings

mike


Can you define "roasted"? Is the grease hardened? Steel turned blue?
How long did it last? Do you know the temp it's seeing? May be as
simple as going to a higher temp grease but normally that will require
a change in the bearing as well. Temp stabilized bearings are
available and cheaper than ceramic but it depends on the conditions it
is seeing.

On Tue, 23 Oct 2007 16:10:44 GMT, "Michael S"
wrote:


no colour change in it and there was no grease left in it. balls and race
are quite sloppy and grindy. guess roasted wasn't quite the term to use but
the sheet metal next to where the bearing is mounted is a lot hotter than I
can touch. crammed some grease in it last night and it ran quiet for about
2 minutes, but guess a high temp grease would be a good thing. of the
beaings I have found looking around so far a 608zz w/ steel shields is whats
in the furnace. to bad its $8 shipping for $2 and change for 4 bearings

There are solid lubricants intended for bearings in high temp service.
You can special order bearings from the mfr pre-lubed with this stuff.
It looks like caked and hardened grease packed around the balls and
retainer. Here's an example...

http://uniquetechnologies.com/serv01.htm

--
Ned Simmons

"Michael S" wrote:

to bad its $8 shipping for $2 and change for 4 bearings


I'd buy a few extra and go with it unless it is a real pita to change out.

Wes

On Tue, 23 Oct 2007 16:10:44 GMT, "Michael S"
wrote:


no colour change in it and there was no grease left in it. balls and race
are quite sloppy and grindy. guess roasted wasn't quite the term to use but
the sheet metal next to where the bearing is mounted is a lot hotter than I
can touch. crammed some grease in it last night and it ran quiet for about
2 minutes, but guess a high temp grease would be a good thing. of the
beaings I have found looking around so far a 608zz w/ steel shields is whats
in the furnace. to bad its $8 shipping for $2 and change for 4 bearings

mike
I don't know where you are located but see if you can check with a
local bearing distributor (Motion Industries, Applied Industrial,
Kaman or any of the independents. They may have it on the shelf or can
bring it in from one of their distribution centers.

well on a run into town I stopped at skate board shop and spent a few bucks.
furnace is much better and if they don't last they are cheap and handy.
maybe get something a little more suited all the way around ( grease and
bearing properties) once I can get to the big city... and thanks for the
ideas guys

mike

"Michael S" wrote in message
news:BpeTi.45944$%B2.33305@edtnps82...
We have a bearing thats nearly roasted in the natural gas furnace. Its a
NMB 608Z, near as I can figure this is the same as a 8x22x7mm bearing.
Its for the exhaust fan near a lot of heat. I found tons of inline skate
bearings that are 8x22x7mm, now the big question is does anybody have
links or info regarding whether I should go ceramic,stainless, or just the
cheapest steel ones I can get. after application data ? so I can wrap my
head around this stuff. Thanks.

Mike