Extremely low temperature bearings?

[Anokiernan]

I've been asked to build a device that operates in a -100 degree F environvment. The mechanism requires 10 rotational bearings, they could be plain, roller, ball etc... I simply can't find bearings that are rated for these kinds of temperatures. Has anyone had any experience with something of this nature or have any ideas? Thank you!

 

[dvd]

I've used these bearings for high-temp, you might have luck with them for your application:

http://www.graphalloy.com/

 

[Anokiernan]

A few follow-up items i forgot to mention:

the operating loads for the bearings will be in the area of 750lbs, oscilating motion 0 to 90 degrees with intermittent use, approximately once every 2 hours. The environment involved has a tendancy to coat anything within it with a half an inch of fine ice from the humidity in the air.

 

[romke]

i would opt for sealed grease lubricated roller bearings, given the operating temperature and the fact that the bearings do not fully rotate. the best thing you could do is talk to a reputable bearing manufacturer (SKF and the like) to discuss the specific operating circumstances (brittling of metal, reduced acceptable bearing loads, lower bearinglife) and their experience with specialized low temperature greases; some aircraft greases might be suitable. you will need a synthetic base fluid and an special type of thickener.

 

[diskullman]

Or look into some solid bearing lubricant at

http://www.uniquetechnologies.com

Russell Giuliano

 

[unclesyd]

I agree with romke that a sealed SS ball bearing would be the ticket. You can go with 440C bearings at your temperature. SKF did make low temperature bearings in England.
The only thing that worries me is your mention of water ice forming on the equipment. Ice in a bearing bad in that it can cause the ball or roller to skid instead of rolling especially in intermittent operation.

I would also give GGB a call and discuss your requirements.
Here are two groups of bearings that may have possibility of working.

http://www.ggbearings.com/products-detail.asp?MaterialID=2&Group=1

http://www.ggbearings.com/products-detail.asp?MaterialID=7&Group=1

 

[Anokiernan]

Thanks for all of your help guys

 

[dinjin]

I would call Timken and simply see if a wheel bearing might work at that temperature. You did not mention any envelope. A sealed taper roller bearing might be the
answer. Nice to have something off the shelf to save costs.

 

[EngineerTex]

I hate interjecting things that may be too far off the wall, but for loads, speeds and displacements that are this minimal, have you considered a bushing? I have used Nylatron wear pads to support thousands of pounds as a bearing in exremely harsh environments, although I don't know about the lower temperature limit on Nylatron. The material is Nylon impregnated with molybdenum disulfide and I used it on a boom carrying 2500 lbs, rotated by hand.

Hope that's not too wild.

-T

Engineering is not the science behind building things. It is the science behind not building things.