Galvanizing Repair

[maneesha0702]

Does anyone have experience with field repairs of galvanized steel due to welding, abrading, etc.? Can you add any specifications if any?

 

[MiketheEngineer]

There is a spray on paint that is supposed to "act" like galvanizing. You can find it in any metal working magazines... Not sure how good it is....

 

[kenvlach]

See Repairing Bare or Damaged Areas of Galvanized Steel

http://www.galvanizeit.org/showContent,179,221.cfm

"ASTM A 780 authorizes three accepted touch-up and repair methods:

Applying zinc-rich paint,
Coating with zinc solder, and
Spraying with molten zinc (metalizing).

The touch-up and repair method chosen should consider the specific use of the galvanized steel and the performance characteristics of each of the three methods. Corrosion protection should always be the primary consideration, but certain uses and conditions may warrant selection on the basis of other performance characteristics."

ASTM A780-01(2006) Standard Practice for Repair of Damaged and Uncoated Areas of Hot-Dip Galvanized Coatings

http://www.astm.org/cgi-bin/SoftCart.exe/DATABASE.CART/REDLINE_PAGES/A780.htm?L+mystore+tyak1680

 

[unclesyd]

Here are two "cold galvanizing compounds" that I've used with some degree of success. I normally use the ZRC brand as it does a good job around a salt air environment.

http://www.zrcworldwide.com/p_zrc.asp

http://www.clearcoproducts.com/cold_galvanize_sprays.html

Cold galvanizing is a misnomer since it is just highly zinc loaded paint.

 

[kenvlach]

I've used the ZRC zinc-rich paint myself. Looks like it meets or exceeds the requirements of
MIL-P-21035B PAINT HIGH ZINC DUST CONTENT, GALVANIZING REPAIR

http://assist.daps.dla.mil/quicksearch/basic_profile.cfm?ident_number=14463

 

[maneesha0702]

Thanks for all the help.

 

[MSteele1]

Galvilite from ZRC is a better solution. It has the 95% zinc film as the ZRC Cold Galvanizing Compound but is made in a silver color that blends in with new hot dip galvanizing. Best performance by far of any of the products we have used.

 

[UcfSE]

There is also a zinc-rich primer covered under SSPC-20

 

[csd72]

Check out:

http://www.galvanizeit.org/

 

[HgTX]

Watch your zinc percentages. Some products proudly report some high percentage on the label but it's actually a reference to the purity of the zinc, not how much zinc is in there. So you could have 60% zinc dust, but that dust is 95% pure, and it'll say "95% pure zinc" on the label.

(Kinda like that bottle of "100% pure aloe vera" gel I have in which aloe vera is about the 3rd ingredient--but by gum it was 100% pure before they mixed it in with all the other stuff.)

Hg

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