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Jet Engine Test Equipment OEM needs Hardware Coating...

2005

Hello,

I work at an engineering firm that makes jet engine test equipment. Our biggest customer will not allow us to use zinc or cad to plate our parts. We buy a lot of black oxide coated hardware and need a good plating solution. We tried Armolloy but were not happy with the rust protection. I have recently been turned on to a Xylan or PTFE coating. The trick to our hardware is that is subjected to high levels of vibration. Our standard procedures require positive locking features on all the bolted connections. This includes flex lock nuts and safety wire. We some times cannot use the two listed above and have to result to loctite. How will the locknuts and loctite hold on the PTFE finish? Is there a better option out there for us?

Thanks

Brad Lederer
Jet Engine Test Equipment - Houston, Texas

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2005

Hi Brad.

Cadmium and zinc offer sacrificial cathodic protection. None of the other coatings you mentioned do. The only cathodic protection material other than cadmium and zinc that is practical is probably aluminum. The aluminum can be applied to the components by electroplating (a proprietary non-aqueous process) or by Ivadizing.

But aluminum plated or Ivadized hardware is expensive, so you might inquire of the suppliers of dip-spin coatings (like Doerken, Magni, and Metal Coating International) whether they have any such coatings with only aluminum and no zinc in them. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey