On Jul 15, 2:26*pm, "Joe AutoDrill" wrote:

I sell a product that acts basically like an air cylinder. *It has a tube
(hard chrome plated inside for you metal guys) with a quill (hard chrome
plated also) and some rubber seals inside.

One of my customers is a medical giant. *They can't have ANY type of
lubricant in the cylinder as they run the drill or the FDA comes in and
gives them hell.

How about a stainless bellows to seal the tube/shaft, then use
any lubed seal you like. High-vacuum apparatus also doesn't
like most oily materials, and is frequently brazed/soldered with
a sylphon (bellows) for this reason.