Try googling 'magnetic bearings'.

What about using plastic bearings loaded with self lubricating stuff* ???

They use them on warships for prop drives so they must be good.

*technical bits that I don't know about.

John.

There are other bearing materials. Knowledge of the application would help us in making any recommendation. And the problems that you have in using PTFE. Delrin UHMW-PE both can be used as bearings. Their use will depend on the application.

Try the bearings from IGUS. Low friction +low wear. Use them very good results. Broad offer.

Uhh, how about balls? Say, ABEC 7, well lubricated. With care, and a decent manufacturer, you should be able to beat PTFE all hollow.

If you have a balanced load, the best you can get (for low friction) is an AIR BEARING. They are a bit complex though!

Graphite impregnated nylon for instance?

AIR BEARINGS WORK WELL. PERMANENT MAGNET BEARINGS WORK WELL TOO.

Isanguineti,

Please tell us a little more about your application. You can't just say "which bearing has the lowest friction?". The real answer depends on the shaft material, surface roughness, lubrication, speed, load (how much and whether perpendicular or parallel), temperature, whether we can run this thing in a vacuum or dry nitrogen, etc.

Depending if you need roller or a linear bearing, ceramic bearings are low friction. Boca bearing and VXB offer hobby and industrial applications. If is going to be in a dusty or more harsh environment you can try the ball-less bearings that are oil impregnated bronze.There is no slides or balls to gum up the lube or product in. I would recommend checking out Global Spec to search for some bearing manufactures.

Rulon bearings are available in a variety of grades for a wide range of applications. Contact Joe Cativo at Saint Gobain Performance Plastics in Bristol, Rhode Island with your specific application and he should be able to recommend a solution.

Actually, it would be best to describe the application requirements and the reason why PTFE would not be acceptable. Important questions are: 1) bearing pressure, 2) linear/rotary speed, 3) mating surface and finish, 4)chemical exposure, 5) other foreign materials and concerns?

Rulon bearings contain PTFE.