Metal finishing Q&As since 1989

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Wear treatment for aluminum yarn rollers

WHICH TREATMENT WOULD ENSURE GREAT LIFE SPAN TO aluminium ROLLERS WHICH REMAINS IN CONSTANT CONTACT WITH POLYESTER YARN AND RUNS AT 15000 R.P.M. WE ARE USING PLASMA COATING, BUT IT'S VERY COSTLY AND YET WE GET LESS LIFE.

Nilesh Kapoor
[P.O.Y.SPARES] - Ahmedabad, Gujrat, India
2004

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You might try boriding the aluminum rollers. If I remember correctly this has worked on thread spooling machines in the past. John Davis - Berthoud, Colorado, USA 2004 Sorry, plasma coating does not say anything. Which plasma coating? there are literally hundreds and vary from relatively low energy to very high energy systems which has a massive effect on the properties of the application. All coatings that are good will be more expensive than the cheaper alternatives. That said, have you tried chrome or electroless nickel? James Watts - Navarre, Florida 2004

Based on serious studies carried out by DuPont they seem to have concluded that Electroless Nickel with dispersed round diamond particles is (or at least was 10-15 years ago) the leader, outlasting Ceramics and Tungsten Carbide by a factor of 2 or 3 and chrome by a factor of 10. Obviously, the study takes in consideration the wear versus thickness. Is it expensive? None of us has anything to say as we know nothing about your costs.

Guillermo Marrufo
Monterrey, NL, Mexico
2004

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2004

When I read this posting I immediately said to myself, how about Hardcoat Anodize, either with or without Teflon.

Then I read all of the other responses & saw nobody else recommended that.

My shop only does anodize, hardcoat anodize, & chromate conversion coatings & that is where my knowledge lies. I am not familiar with the other coatings you recommended, but after I saw the responses I would like to know why you would chose those over hardcoat? Are they better? Just curious for my own knowledge.

Thanks

David A. Kraft
- Long Island City, New York

Hardcoat anodize can be put on parts like the one mentioned. The disadvantages of hardcoat in that application are that anodize usually has poor frictional properties when used with polester yarn on high speed machinery. Also when the roll is stripped to be recoated it becomes smaller on the OD and larger in the ID.This is a big problem after numerous recoatings as rolls must be a very specific size on the OD to insure proper tension on the yarn and bearings fit in the ID.

Todd Osmolski
- Charlotte, North Carolina, USA
2004