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Hardcoat Anodized Teflon Impr parts spark when hit together - a problem in Class 1 Div 2 area

We use Hardcoat Anodized Teflon Impregnated AlMgSi part racks. They spark most times when hit together. We are adding a hazardous (heptane) process in a class 1 div 2 area which these racks must travel through. We need to eliminate this spark. We are open to stripping and re-coating these racks. We tried two coatings but the coating process temperature softened the aluminum racks and made them unusable. Coating must not peel or flake. Help !

Larry Mazan
- Franklin Lakes, New Jersey
2007

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First of two simultaneous responses --

Maybe I didn't get it but can't you just paint them or coat them with plastisol or similar?

Guillermo Marrufo
Monterrey, NL, Mexico
2007

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Second of two simultaneous responses -- 2007

Aluminium and PTFE is a prime example of two relatively inert materials which react violently. This is not usually so bad when just surfaces are involved but if swarf or powders get mixed you can get an explosive mixture. Accidents have happened when cutting both on the same machine without thorough cleaning.
It is difficult to advise an alternative without detailed knowledge of the application but one of them has to go.

Geoff Smith
Hampshire, England

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Hardcoat Anodized Teflon is not the same as the type of Teflon used on fry pans. Because of this it will not offer significant protection against metal to metal contact. Don't get me wrong. You can't use the specific type of Teflon on fry pans.

More info regarding your needs and process will help in recommending the proper coating for you. Should you require a tough Teflon coating with excellent chemical resistance check out Teflon's ETFE coatings.

Louis Zapata
- Manila, Philippines
2007