Vinyl Coated 72 Steel

[montyb]

Any one in California know if it is illegal to hydro a vinyl coated steel tank?

Thanks,
Montyb

 

[ScubaDadMiami]

If you are talking about the interior coating that was inside the tank, these days, people tumble the tanks to remove the coating. If they pass hydro, they should be fine.

 

[DA Aquamaster]

The problem with the vinyl coating in some steel 72's is that the coating develops pinholes that can then trap moisture and lead to pitting.

The coating does not cause any problems with a hydro test per se, but part of a hydro is a VIP and most test facilities will want the coating removed to ensure there are no pits underneath before they will pass the tank.

Tumbling is the normal method of removal, but a LOT of tumbling is required as the stuff is pretty persistent.

 

[pasley]

What DA Aquamaster said. From what I can read on the DOT sight, the VIP is part of it and how can they check the surface for rust or damage if covered with vinyl? In addition it provides and excellent breeding ground for rust if a pin hole should develop. Last of all, when the Hydro is done, they will have to stamp the metal and that may damage the vinyl coating.

 

[pescador775]

The vinyl coatings that Voit used in the early 60's did not stick to the underlying zinc very well and would peel off. Generally, I don't like these coatings for the reasons stated. Tank interior coatings were usually a two part epoxy paint and had similar problems.
Pesky

What DA Aquamaster said. From what I can read on the DOT sight, the VIP is part of it and how can they check the surface for rust or damage if covered with vinyl? In addition it provides and excellent breeding ground for rust if a pin hole should develop. Last of all, when the Hydro is done, they will have to stamp the metal and that may damage the vinyl coating.