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How to define thickness of teflon coating on heat coil?

March 12, 2012

Q. Hi Mr,
I'm going to coat a heat coil surface, but I don't know how to define the layer thickness of Teflon; please recommend.
The heat coil will be used to heat NaOH 1.25% Reagent directly in a glass tank.

Thank you!
David Lv

David Lv
- Suzhou, Jiangsu, China

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Hi, David.

Teflon is a Dupont trade name. The only time I've seen similar materials applied to items like this it was via powder coating in a fluidized bed. It did not seem to me that there was any way to control it once the fluidized bed tank was made up. I think the powder manufacturer can answer the question. I'm not 100 percent sure that this is quite the coating you are looking for even.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
March 13, 2012

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I never had any luck using teflon to mask off racks, so doubt seriously if it will work on heaters.

The heaters that I have used that were "teflon" were teflon tubing over a round rod heater.

Teflon will not last with a regular heat density heater. It needs to be a derated heater (1/2). If you want longer life, you need to use double derated heaters(1/4)

Teflon has a coefficient of expansion about 10 times that of steel, so when it heats up, it swells.

Teflon heaters do not last forever and are a bit expensive.

I did use a teflon covered braided insulation over a single wire element. Double derated. It did not like places where it overlapped. It was a nice unit. I bought several as prototypes. They are nice for tiny plating tanks.

James Watts
- Navarre, Florida
March 16, 2012