jscpm
Titanium
- Joined
- May 4, 2010
- Location
- Cambridge, MA
In choosing off-the-shelf, pillow block style sleeve bearings, I am a little confused why the bearings with the apparently better specs are cheaper.
For example, at McMaster some of the choices for 5/8" mounted sleeve bearings are as follows:
Dry Acetal 5202N14, radial load 95 lbs, price $20.39
Babbit 6359K13, radial load 145 lbs, price $68.63
Oil Embedded 5912K6, radial load 850 lbs, price $20.51
High-Speed Oil Embedded 3813T12, radial load 1550 lbs, price $10.25
So, as the radial load capacity increases, the bearing type generally gets cheaper and cheaper! In my application the journal is a shaft that has a grinding wheel mounted on it running at 1750 RPM doing form grinding on a die. So, in my case maybe I want the Babbit after all because it is fixed alignment, so I will get a more rigid wheel. The other bearings are "self-aligning" so they could potentially move more I guess and result in more vibration in the wheel, which would be undesirable.
What are some of my design considerations here when choosing between these bearing types?
For example, at McMaster some of the choices for 5/8" mounted sleeve bearings are as follows:
Dry Acetal 5202N14, radial load 95 lbs, price $20.39
Babbit 6359K13, radial load 145 lbs, price $68.63
Oil Embedded 5912K6, radial load 850 lbs, price $20.51
High-Speed Oil Embedded 3813T12, radial load 1550 lbs, price $10.25
So, as the radial load capacity increases, the bearing type generally gets cheaper and cheaper! In my application the journal is a shaft that has a grinding wheel mounted on it running at 1750 RPM doing form grinding on a die. So, in my case maybe I want the Babbit after all because it is fixed alignment, so I will get a more rigid wheel. The other bearings are "self-aligning" so they could potentially move more I guess and result in more vibration in the wheel, which would be undesirable.
What are some of my design considerations here when choosing between these bearing types?