Design of ball bearing to operate in water?
Design of ball bearing to operate in water?
(OP)
I'm thinking about using a ball bearing in an application where the bearing would run immersed in fresh pond water. I'd like to hear from anyone who has a similar application: what are the load conditions, bearing material (stainless, ceramic, etc?), type of water, and the real-world vs. calculated life.
In my case, shaft speed is 1200rpm and the load would be 100lb radial. Bearing will be in the 6018 to 6020 range. My basic L10 estimates are very high due to the low load which means with contamination and material adjustments this may be feasible.
In my case, shaft speed is 1200rpm and the load would be 100lb radial. Bearing will be in the 6018 to 6020 range. My basic L10 estimates are very high due to the low load which means with contamination and material adjustments this may be feasible.





RE: Design of ball bearing to operate in water?
One school seals them up and vents them through long hoses to high parts of the structure.
The other school cuts the top of the banjo open, and runs them 'mud lubricated' for as long as they last. They start with regular axle lube, to which is added whatever spills in as the unit travels through mud/ water/ whatever.
Speeds are generally very low.
Everglades 'muck' is definitely _not_ fresh pond water.
Mike Halloran
Pembroke Pines, FL, USA
RE: Design of ball bearing to operate in water?
RE: Design of ball bearing to operate in water?
Mike Halloran
Pembroke Pines, FL, USA
RE: Design of ball bearing to operate in water?
Ultimately I would use one of the more corrosion resistant stainless grades but any stainless bearing in water would be a valuable datapoint.
RE: Design of ball bearing to operate in water?
http://www.lignum-vitae.com/
http://www.duramaxmarine.com/bearings.htm
RE: Design of ball bearing to operate in water?
Mike Halloran
Pembroke Pines, FL, USA
RE: Design of ball bearing to operate in water?
So I'm thinking a bearing made entirely of hard materials might be more robust against an abrasive contamination event and flush free without retaining the abrasives. Ceramic or stainless ball bearing is an interesting answer(?) to the problem.
RE: Design of ball bearing to operate in water?
RE: Design of ball bearing to operate in water?
ht
However, although your life may be doubled, if submerged and running at 1200rpm, you might be doubling it from 1 day to 2 days....
RE: Design of ball bearing to operate in water?
RE: Design of ball bearing to operate in water?
I was with Unique Technologies for a while, and they would sned bearings out for additional heat-treating for corrosion resistance, then fill with solid graphite lubricant. They called this process "Cobra Blue",
http://www.uniquetechnologies.com/literature.htm
They do not mention the "Cobra Blue" on their website.
Russell Giuliano
RE: Design of ball bearing to operate in water?
RE: Design of ball bearing to operate in water?
RE: Design of ball bearing to operate in water?
We use them on hydro turbine shaft bearings with very high loads and they can last 50 years or more, stainless steel shafts are common...simple 304 is fine.
Machine and clearance it as though you were installing a plain babbit bearing and it will nearly last forever...just don't let it ever dry out once its wet since they must stay wet or they decompose.
Typically the wood is shipped encased in wax to keep it moist from the initial cutting, once you immerse the wood it must stay wet.
RE: Design of ball bearing to operate in water?
http://www.thordonbearings.com/
http://www.lm-tarbell.com/plain_bearings.htm