Solutions to paint corroded steel still wet 2

[fala]

Hy, my problem is the following :

We run a paper machine and the wet end structure (steel )of the machine is starting to rust. The original paint is damage on some areas and the rust has installed itself. The damage areas are continuously operating in a wet, warm (60 C) and corrosive conditions.

My question is : Since we shut the machine dowm every 6 weeks for 12 hours, is there a way of repainting the structure in those type of shut down ? We cannot sandblast the area since it wiould requied a longer shut than we have.

Is there a type of product or paint that can do this job ?

Thanks

 

[sreid]

Take a look at Loctite Extend.

http://www.loctite.com/int_henkel/loctite_us/index.cfm?&pageid=130&layout=1

An appropiate top coat is still required.

 

[EdStainless]

There are a number of top coats that will stabilize your situation, but to really stop the corrosion and protect the metal you will need to clean, dry and blast. Adhesion is the key.
You might try looking at some marine coatings (for boats).

= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection

http://www.trent-tube.com/contact/Tech_Assist.cfm

 

[0707]

Since you shut the machine down every 6 weeks for twelve hours maybe you should try BELSONA, which has good corrosion erosion resistance properties in some application like yours.
Luis

 

[MechanicalChef]

Have you considered epoxy-paints?

http://www.por15.com/

- this is also good stuff too. Easily meets the temperature constraint. I think it's actually a polyurethane. I think it might be able to meet the wetness/corrosive constraints as well.

 

[mshimko]

There are a number of coatings that are formulated to adhere and cure when applied to wet surfaces.

I first tried one almost 10 years ago when we were unable to control the constant formation of consdensate. The coating (Euronavy ES 301, I believe) worked very well. There are other brands with similar properties, but I've no personal experience.

All in all, though, you cannot over-emphasize the importance of surface preparation. A clean surface is paramount.

 

[gvanbeek]

For this application the best way forward is to just paint a little bit of the machine on each field day.

Pressure wash the area to be painted. Use needle guns to clean the surface (soda blast, and dry ice are not as effective per our testing). Dry just the area to be painted, use plastic sheeting to keep water from dripping onto the area. Check for the presence of salts (e.g. chlorides in your application) using a test like Chlor test by Chlor Rid.

Use a good epoxy coating that is suitable for marginally prepared surfaces and is suitable for splash and spill. Test several different materials in the same area to benchmark thier performances against one another. Use these comparisons to determine which mfg to choose during future field days.