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Tough, low friction coating for conduit interior needed

 

I have an application that requires a very low friction yet tough coating to be applied to the interior of a spiral wound stainless steel conduit. I suspect a teflon may work, but there may also be other choices.

The conduit interior diameter is 1 inch, max length 6ft. The environment is 100-120F with possible moisture. The interior of the conduit (coated side) will be abraided by a 0.5 inch nylon shaft sliding intermittently through the conduit at speeds of up the 120 inches per second, with possibly significant contact loads due to bends in the conduit. The conduit only needs to survive this abrasion for 50-100 hours before it is replaced. Any recommendations.

Lyman J Petrosky
- Madison, Pennsylvania, USA

Lyman,

You pose two problems. First a low coeffic. of friction and secondly wear resistance.

For wear resistance and flexiblity isn't polyurethane an ideal answer? Very high flexibility.

But, apart from the 2 component paint (expensive, not v. flexible, very hard,super smooth finish) I only thought that it only came in sheet or moulded form and in different 'hardnesses or flexibility'... you'd have to check with a supplier as Pu was hardly something I ever got into due to its lower chem. resistance.

The temperature you gave isn't too high and the speed of 600 fpm isn't too fast. My first thought was Polyethylene but that is a soft material. Teflon? Dunno. Very low friction but not as abrasion resistant as Pu, I would have thought.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).