Steel Tank Exterior (can it be redone)

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I was always under the impression that you couldn't repaint tanks. I have some faber blue steels that have some scratching but nothing through the primer so far. I would love to repaint them but always thought it was a no-no with the hydro guys.
 
To Quote the Luxfer inspection guide: "CONDEMN all cylinders that were repainted and heated over 350°F (175°C) to dry or cure the paint." - But note that this applies to LUXFER cylinders, which are ALUMINIUM.
 
I'm like AfterDark w/ my painting skills. So can we clean the rust off (light sand....) then rub with isopropyl alcohol to dry it out then use metal primer followed by galvanized paint (spray or brush)?
Thanks
 
For touching up painted steel tanks. Hand wire brush the rusted spot. Wipe down with wax and grease remover. Brush on POR-15. Top coat with a color to match.
 
I didn't read the entire thread, but my steel tank from the 60s was getting some rust spots so I stripped it and sanded it and painted it with boat paint. 20 years later it has a couple of small rust spots that I need to touch up. I have not tried it yet but I read that Yellow Zinc Chromate Primer is a good choice, possibly followed by boat paint (?). I tried the spray-on galvanizing paint and it did not hold up well. Perhaps with a coat of a more durable paint over it....

For several years after I painted it I had to explain to the tank-filling person that it was not heat-treated and probably would not explode when they filled it.
 
If you’re stripping the tank completely you can use ZRC from a gallon can. Brush it on. You could leave the cold galv bare or top coat it with an enamel.
We use ZRC on structural steel with outstanding results in outdoor, underground and immersed environments.
I would not use POR-15 for a complete strip and recoat. POR cures hard and I’m not sure it will tolerate fill cycles very well. It may, I just don’t know.
My understanding from my PSI training an inspector should not pass a repainted cylinder unless it has passed hydro since being repainted. You can’t just condem a cylinder because you think it was painted, but you shouldn’t pass it either. You also shouldn’t pass a cylinder if it has stickers on it but that happens all the time.
 
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I recently refinished my 2 steel 100's. The process I used.... Had the paint stripped in an eco friendly process called dustless blasting, it uses water so theres no rising temperature affecting the metals integrity. Next applied Rustoleum cold galvanizing compound. step 3: after about 2 days I applied 2 coats of a Rustoleum light gray and a stencil I made. Last step: after another 2 days, 2 coats of Rustoleum clear.
 

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The short answer is yes. No heat-cured paint is permissible on any kind of tank.
Ill have to look that up because steel tanks were not in that catagory of not to do's. The last word I got was no regarding Al tanks but if you were to get a steel tank painted, insure the tank did not exceed something like 400 degrees on the curing process. (How would any tank filler know what paint process was used ?????)

Other than curing the biggest problem with refinishing tanks is filling in the scrapes and gouges to make a smooth finish. This act alone covers up the tank fail criteria of gouges etc. That is the reason for not passing repainted tanks as a blanket rule, not the tanks metal tempering temperature factor.

I myself would not accept a tank that has been painted for a vis inspection. Why. Part of the inspection is to check for straight tank sides to insure no ballooning is happening, and the obviopus gouges in the sides. The only ONLY paint job that can be trusted is the one that is done by the manucfacturer. Anything else is subject to problems. You can not destroy a tank if it fails. You return it to the owner and he has body work done then repainted and than takes it to the next inspector shop where it passes. The owner either sells it or uses it. My stand on this is not PSI's stand perhaps but it is my stand.
 
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