Galvanize weld connection

[altecdesigns]

I have L4x4X1/2" galvanize angle irons with nelson studds staggerd into them. now am faced with cutting off the studds a nd putting them into the center of the angle irons. i am faced with galvanize angle irons that have to be rewelded into the center of the L4x4x1/2". what recommendations do you have for me?

 

[Sciscoe]

Not sure what type of galvanize environment you are dealing with, but ANSI has standards for galvanize regarding thickness of coating and type of galvanize process. We weld thin coated galivanize channel which I think is a ANSI 423A and "touch-up" the welded spots with a "cold" galvanize. It is applied like spray paint from a hand held spray can. We have been pretty happy with a Rust-oleum Cold Galvanizing Compound which, according to Rust-oleum Industrial Brands, is 93% pure zinc in dry film. The resulting coating has a flat finish appearance, however I have seen other finishes as well. If you review your specific galvanize ANSI standard, it most likely allows cold galvanize application up to a specified percent (%) of total coating area. Even in a hot-dip galvanize environment the application of cold galvanize as touch-up is permitted in the standard. Depending on the size, you may also hot-dip galvanize the entire assembly (ASTM A 123-89a). Our metal plate supplier charges by weight - they weigh pieces before coating, acid bath and wash the pieces, then hot dip and weigh after coating - we are charged the difference on a per 100 lbs basis. Hope this helps. Also, you probably already know that welding galvanize emits fumes which your welder should NOT inhale. Good luck.

 

[HgTX]

I'm guessing this is for some kind of anchorage assembly that will be embedded in concrete and not exposed to the elements, so the "cold galvanizing" Sciscoe mentions should be fine. Make sure to get the welding fume off the area you're going to paint. (For exposed outdoor applications, we've found that the paint doesn't hold up well even when applied in strict accordance with manufacturer's recommendations, and even less well when applied the way most people would probably do it. It starts to rust through after a couple of years.)

I'm assuming you can't shoot the studs into the angle and that you'll be fillet-welding them instead. Check with the electrode manufacturer to see if they recommend its use for welding through galvanizing, or if you need to grind off the zinc. Is this a D1.1 structural welding application? See the "Welding galvanized carbon steel thread" at thread178-98196 .

Also, AWS has a publication called "Welding Zinc-Coated Steels". I don't have a copy so I can't tell you what's in it, but there's probably something useful there. See

http://www.aws.org/cgi-bin/shop/flyall.html?mv_arg=WZC

(or look in the "Base Metal Weldability" section of their online catalog).

Hg