Does anyone know if the product is still around that you mix a powered zinc in a gallon or quart paint can with a outdoor paint type product. You painted it on the boiler and it dry's a black or battleship grey color? I can't remember the products name but I remember is being used on all boilers during the rebuild process. Does someone know what the product might be?

Thanks
SMH

It sounds like Carboline Carbozinc 11, you can see a product data sheet (PDS) HERE. This primer is good for 750° F continuous exposure.

This company makes a good product for boiler shell and steam pipe coating.
http://www.dampney.com/

Surface prep is important. Info from http://hytechsales.com/download/HiTemp%20Product%20Description.pdf



So ideally the boiler exterior would be abrasive-blasted before painting. Most folks are extremely reluctant to abrasive-blast a boiler attached to steam locomotive running gear. If this is done, you must take serious measures to keep finely-powdered abrasive dust out of the bearings, cylinders, etc. Alternate surface prep methods just aren't great. Wirebrushing removes loose rust flakes but doesn't touch the rust in the bottom of the pits. Dry-ice blasting removes loose rust flakes, but doesn't remove rust in the pitted areas.

Does anyone make a rust-converting primer/paint that will withstand boiler temp (approx. 400F)?

Many boiler coatings are designed to be cured at 300F. If that's not practical - i.e. if the boiler isn't going to be fired up immediately - then you must use a paint system that cures at room temp.

- Doug Debs

What about soda blasting?

-Hudson

get out the nail hammer and pound away.

(or just plastic cover all bearing parts)

If you blast your going to have material flying everywhere, you may want to be able to pick it up and re-use laying down plastic or set up a funneling system with the plastic while you blast it trickles down to collection.

but on 765 we just nail hammered the outside, but sandblasted the interior.

we talked about a paint earlier on the board thats for boiler interior, I'd have to find that name again (if its still available)

A couple of ways to safely clean the shell surface. You can have the surface dryice blasted with pellitized dryice. This will remove rust and scale down to a dull gray surface. Another way is high pressure water blasting. Water jets of around 8000PSI are used to descale/derust the shell surface. Qualified licensed operators do this type of cleaning.

There are many coatings good to 1000F however what kills the coating is the insulation and environment under the sheetmetal and insulation. Dampney company has hitemp coatings made especially for this type of application. try Thurmalox® 225 HD

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The boiler interior paint is called Apexior.
No matter how careful you are with sandblasting, it's going to get into everything. No matter how much plastic you cover stuff with, it's going to get into where you don't want it.
Don't ask me how I know this.

Bill Cosby: Don't touch there....so I grabbed my head!

What I'm looking for and it's my fault for not being specific enough is the outside boiler shell paint.

Thanks!!

SMH

BobK's suggestion to use ultra-high-pressure water blasting is a good one.

For 4-6-2 S.P. 2472, we hired a ship repair / maintenance company to waterblast hard scale from the boiler interior. The scale was incrediably durable - I tried pounding hard with a sledge hammer and chipping hammer on a piece of boiler tube, but the scale didn't flake off. Waterblasting did the job safely, cleanly, and at a reasonable cost. The pressures used can cut off a man's arm, so this is a job best left to the pros.

- Doug Debs

Has Apexior also been used on the outside of a boiler?

Apexior is not the best material for the outside of a boiler.

As an example of a phosphoric-acid rust converter, see Endcor 450 (good up to a nominal 500 degrees F).

If I wanted a boiler 'finish' paint, exclusive of price, I'd look carefully at the Thurmalox series, particularly Thurmalox 240 and 242.

Attempting to remove scale mechanically, with sandblasting, needle guns, chippers and hammers is stone age technique. No offense or pun intended.

Seriously, with modern chemical technology, the scale can be lifted off and dissolved without using corrosive acids. It has been discussed many times on many forums. There will always be the ' preserve the status quo ' proponents and the ' horror stories ' of someone who did not follow he simple guidelines. There are many in the steam preservation community who are getting perfect results with Terlyn LSB 4000. It gets under scale, pops it loose, breaks it up into loose chunks that can be washed out, and forms a protective poly-acrylate thin film on the boiler interior. All this has been done and proven over many years with boilers in normal and high demand steaming service.

You cannot let a boiler stand cold and wet. It must be either dry, steaming or under a nitrogen inerting blanket. Simple physics and chemistry, it is standard procedure in industry and utilities, there is no reason to not work on flanged wheel steam.

The result is a boiler that is internally protected from oxygen pitting and the more severe chloride pitting from dissolved concentrated salts in the water. From a chemistry standpoint, it is automatic and self-regulating. Being an amine instead of an alkali, the water pH buffers at 10.2. It cannot cause caustic stress corrosion cracking. Alkalinity testing is not necessary. The use of sulfite oxygen scavengers is not necessary and not recommended. The associated tendency for sulfite to cause foaming and hard sulfate scale disappears. The only testing needed in operation is electrical conductivity / TDS with a pocket sized $ 37 meter to regulate blowdown. This is the factor that fits the treatment to your operation.

This is not a commercial or 'info-mercial', simply the testimony of a steam professional and preservation hobbyist who has used it for years in both industry and play with perfect results.

A few things.....

Thank you Mr. Hogger for bringing up LSB 4000, it gets along very well with Apexior (when the surface is properly prepared, near white to white metal). That is to say lsb does not act to remove the coating.

This is a phenomenal exterior coating product for locomotive boilers and is not overly priced. http://www.dampney.com/ProductLine/tabi ... -260C.aspx

Dampney does state that the surface must have a white to near white blasted surface. While dry blasting is preferred...... soda blasting is acceptable as is abrasive (sand) blasting with a pressure washer attachment, AS LONG AS the surface is coated as soon as it's dried. They said the moderate surface rust would be of no real concern, the primary objective is proper surface texture and removing the deep rooted rust.

Cheers, Jason