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Steel, Hydrochloric acid and paint

Steel, Hydrochloric acid and paint

Steel, Hydrochloric acid and paint

I am in search of a paint that can be applied to steel and can be removed in ~10% hydrochloric Acid at 180 degrees(C) in ~2 minutes.

To add some information the paint that we apply at approximately 600 degrees (C), comes off perfectly in the acid described above, I believe this is because the polymers that are in the paint vapourize when reaching temperatures of >400 degrees (C).

Note:Hydrochloric acid is very reactive with metallics and not reactive with anything that is hydrocarbon based.

All reseponses and insight appreciated.

RE: Steel, Hydrochloric acid and paint

A bit curious.  Reverse-engineering something you already do???  Don't you have the MSDS & product bulletin???

"~10% hydrochloric Acid at 180 degrees(C)"  -- is this in pressurized water or as a gas in air?

"the paint that we apply at approximately 600 degrees (C)" -- Is this the curing temperature? Or do you actually apply at this temperature, like vitrous enamel.

Is the paint shiny, like metallic flake, or dull, like ceramic powder? What is the purpose of the paint -- temporary masking?

Probably correct about any organic binder burning off.

RE: Steel, Hydrochloric acid and paint

I Appreciate the response.

Answers to questions above:
-In pressurized water for the purpose of pickling (removal of surface oxide, or etching)
-Purpose of paint is for identification purposes only and strip with paint is presently scrapped at pickling stage (yield).
-Present paint is just an aluminum based paint with titanium dioxide and polyers.

The information I left out above is that the present paint that is applied after cooling of strip (also for identifiaction purposes)does not come off in the Hcl condition noted above.

I have conducted trials with several different paints and have come very close to finding a product, but would appreciate any insight

RE: Steel, Hydrochloric acid and paint

As posted above you temperatures seem very high.

One thing about cleaning/pickling with HCl is that it has the propensity to leave the soil attached to the part being cleaned.  Most times it takes a blast of steam to remove the soil loosened by the HCl.

There are some paints/coatings based on CaCo3, similar to white wash and whiting, that are colored by mineral colorants that would probably be suitable for your your service.   

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