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Powdercoat vs Epoxy for inside of Vacuum Reservoir

What is a better finish for rust prevention on the inside of a vacuum reservoir/tank, powdercoat or epoxy? We use a TGIC metallic-powder on the outside of the tank, but need something on the inside to prevent rust. Which is better?

Jamie Cristler
Buyer - Newberg, Oregon, USA
April 29, 2009

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First of two simultaneous responses --

You're confusing two things.

Powder coating is a method for applying paint.

Epoxy-based is a type of paint.

You can have an epoxy-based paint that you powder coat. You can powder coat a TGIC paint. You can E-coat an epoxy paint. And so on and so forth.

In terms of which paint method to use, it depends on how difficult it is to paint the inside. If the equipment is small and you can't get a gun/person inside, you're best off using E-coat to apply the paint. If you can get to the inside, powder paint might work. A regular solvent based paint might be better, too, since you'd have to heat up the unit to a point to get the *inside* to the proper cure temperature.

In terms of which is the best paint to use, an epoxy might be a good choice, depending on what the inside will be exposed to. I suggest talking to your paint suppliers to see what they recommend.

Christian Restifo
- Pittsburgh, Pennsylvania
May 1, 2009

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Second of two simultaneous responses --

As you have a PC plant already why not use an epoxy powder?
To ensure no rust occurs you should treat the substrate with a zinc phosphate solution (not iron phosphate). However,contact a reputable pretreatment supplier. I should point out PC does not prevent rust creep if it is damaged and the substrate becomes exposed.

Terry Hickling
Birmingham, United Kingdom
May 1, 2009

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The epoxy has good chemical resistance, and the inside of the vacuum would be a good place for it. You do know that there are epoxy powders available?

Sheldon Taylor
supply chain electronics
Wake Forest, North Carolina
May 5, 2009