SAF mounted spherical roller bearings

Isn't spherical roller bearing called - ball bearing?

No. The outer surface of the outer race of a spherical roller bearing is spherical (really a slice from a sphere). Therefore, it can fit into a spherical socket and be self-aligning. These are commonly used in pillow blocks so that the blocks can be somewhat misaligned without causing the bearings to bind or overload.

Hi Ken - I think you meant inner surface of the outer race, eh?

For example, the picture shown here: www.skf.com/files/292738.pdf

Best regards,

No, Ken was right for the kind of bearing he was describing. In those, the outer race slides (not rolls) in a spherical socket to allow misalignment.

Thanks for showing your link - I hadn't seen that kind of bearing before!

Dick

Dick - oh yes, I agree - I had forgotten about those for a moment. I usually had seen spherical-mountings used in conjunction with journal bearings, such as line-shaft bearings aboard ships. Thanks!

Funny -- I was also forgetting about the other type of spherical bearing, because I'd keyed on the phrase "pillow block" in the original post. Actually, I think of the type you described as the "real" spherical bearings, and they have the advantage that the shaft itself can be bent or flexing, and the bearing deals with it quite well. The type in pillow blocks deal well with housing misalignment, but not so well with an out-of-true or flexing shaft.

And then there are Heim joints...

Thanks, Ken! Actually, what all this reemphasizes to me is that two heads (or three, or four etc), are better than one. I'ts good to be able to discuss things like this with other fellow engineers!

Look at a price list. For the most part, bearings are priced more by popularity than anything else, since production quantity has such a large effect on cost..

No, spherical roller bearings are not the same as ball bearings. Spherical roller bearings have rollers that are almost cylindrical, but have a large radius instead of straight sides. The race is curved to fit. The result is that the bearing is allowed to rotate 2-3 degrees along the shaft axis. This lets the bearing accomodate shafts that are not perfectly aligned, or that flex in service.

At least now I know what he's talking about beause I do not remember ever seeing a self-aligning roller bearing, now I do.

Thanx,

Thanks Harry - I appreciate the insight.

Go to the SKF site or the Dodge Bearings site

They both are excellent sources.

Thanks for the direction Guest. At these sights I have found a very broad offering. Do you have suggestions as to how to narrow that broad offering to the most popular? Another contributor offered "price" as a limiting factor so I intend to pursue that method. If you have other suggestions - would appreciate. Thanks.

I know of SKF bearings (World famous!), is there also a company or something to do with bearings called SAF too? Please enlighten me, thanks in advance.