high speed bearings 2

[engrnick]

Hi all,

Wondering if any of you have worked with small high speed bearings that are sealed, or at least can handle water. I'm thinking we might need sealed. there will be _some_contaminants. Not much, but the possibility exists.

I've never worked with bearings of this high speed before, so any information you can give me will help with this test fixture.

RPM: 6400
Shaft dia: .250"-.313 or so (TBD)

Thanks!
Nick

 

[Skogsgurra]

6400 RPM isn't really high speed. You can use standard bearings if you follow the design guides provided by major ball bearing manufacturers.

Have used DGBB at 30 000 RPM and seen higher speeds than that.

Hybrid bearings (ceramic balls) have the advantage that centrifugal forces are lower because the ceramic material has lower density than steel.

Gunnar Englund

http://www.gke.org

--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

 

[engrnick]

haha, ok, good point - they're high speed to me.. I've never worked with anything faster than 1000 or so. I mostly use plain bearings.

Thanks for the heads up on the ceramic bearings, I'll look into them.

Nick

 

[geesamand]

You mention some water and dirt. Will these be immersed, constant splashing, or intermittent splashing? There is a huge difference between these conditions.

At that speed the issue is sealing. Contact seals provide good protection from the elements in a compact space envelope, but if they run too fast the lip will run hot, harden, and fail well before the bearing. But if your application has low total hours of usage that may not be a big deal.

A more robust sealing option is labyrinth seal which doesn't really care about speed because there is no contact. These can usually manage splash contamination without issue.

The bearing types I would begin with are angular contact ball bearings and deep groove ball bearings. Selection depends on loading and required rigidity of the shaft support.

 

[engrnick]

thanks for your help, all!