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madman
05-23-2008, 08:31 AM
I am building a 10 foot tall galvanized steel pipe fence around a shop. I was wondering do you buy the pipe galvanized already galvanivzed and how do you weld it? Is a Mig Unit preferable to a stick for this purpose?? I heard (word on the nstreet) that welding galvanized steel makes you sick?? Is this true? Thanx Mike

torker
05-23-2008, 08:38 AM
Mike, we weld lots of galvanized pipe/plate here.
Field work we use mainly 6010.. in the shop we use dualshield wire.
Helps if you can grind off a bit of the coating.
Yup.. it can make you sick if you do enough of it.
Do it outdoors and stay out of the smoke or use a good canister type respirator.
Any fencing outfit will have the pipe in stock or your steel guy?
Russ

rwf71
05-23-2008, 08:43 AM
I'm no expert but I read of a case recently where an experienced welder who knew better was welding galvanized & in 24 hrs was DEAD. I'd say self contained breathing equipment & good ventalation is a must. Like I said I'm no expert but hopefully one (Torker ?) will weigh in on this thread.Be careful. Rick

rwf71
05-23-2008, 08:45 AM
I'm a slow typer, looks like Torker is here already. BTW Russ , have you heard it can kill ? Rick

Randolph
05-23-2008, 08:46 AM
Yes. Welding galvanized steel will make you sick. It also makes you irritated and frustrated and will cause you to kick your dog if you have one. But it can be done. I have been told that the bad effects of welding galvanized steel are like mercury poisoning. That is, it accumulates in your system. I welded galvanized material when I was in my twenties and thought my father didn't know what he was talking about when he said it would make me sick. But if I weld it now I get a really bad headache so I avoid it altogether. I suggest you weld it with stick outside while there is a breeze blowing. Use either 6010, 6011 or 7018. Drinking milk is supposed to help offset the bad effects.

torker
05-23-2008, 09:22 AM
Yes.. I know about all the "dangers" of welding galvanized. Wear a respirator.. simple as that. Not a dust mask.. a canister type resp with approved cans for the material being welded.
I don't always wear one if I'm outside and there is a breeze.
Right now I'm about the only shop here that will touch the stuff.
A lot of weldors don't like it (My weldor hates the stuff)because of the dangers but they also don't like it because it can make you look bad. NOTE... I said grind the coating off where you intend to weld. You're going to bugger it anyway so why not take it off so your welds look better and you cut down on the ugly spatter from trying to weld the coating.
This is just a small job Mike is talking about... I doubt if he will die right away :D
USE A RESPIRATOR!!!!
Russ

Tony
05-23-2008, 09:28 AM
like the others said, remove the zinc before you weld.
since its a fence, MIG should be fine. Note: you can't
(well, it'd be difficult) to grind the inside.

an option to grinding is muriatic acid. stand the pipes up
and soak the last 1" or so -- it comes off relatively fast..
just to be safe leave it outside overnight (fumes).

you'll have to spray it again once you're done or it'll rust
of course.

-Tony

dsergison
05-23-2008, 09:52 AM
do not breath the fumes.

milk will not save you.

wear respirator AND do it outdoors.

it makes your lungs fill with fluid and you suffocate. if youve goten a headache or you cough... it just means you didnt get enough to kill you, just enough to make you a bit oxygen deprived or sick. if you get too much there is not much people can do for you except watch you die.

Randolph
05-23-2008, 10:11 AM
Torker,
This is totally beside the point and I apologize but I cannot help but notice when somebody knows the difference between the words 'welder' and 'weldor'. Most people don't. Probably not important, anyway.

Duffy
05-23-2008, 10:48 AM
Once you have the pipe welded, (with or without removing the galvanizing-your choice,) You really should paint the welded areas with a zinc-rich paint. Ideally this is an oil-based paint with a high percentage of zinc dust suspended in it. It is made specifically for repairing galvanised surfaces. By the way, the problem with the welding fumes is not only the zinc itself, but galvanizing zinc ingot is not particularly hughly refined and can contain significant amounts of cadmium and other good stuff. In addition, if the coating is "cosmetic" as well as protective, the zinc contains about 1% lead to impart "spangle," (the industry's word-not mine,) to make it look good. Remember the shiney crystaline look on galvanized garbage cans?

pcarpenter
05-23-2008, 11:31 AM
Welders/weldors...funny story-- There is a place not far away in a town called Pekin and the business is "Pekin Weldors" I used to make fun of their sign out front saying something like they must have dropped out of Pekin High School...ha ha...:D

Then I realized that it could be very possible that a weldor is the person who welds while welder is the machine used to do the work. So, joke is on me, right? Not so fast. The sign actually says Pekin Weldors'...(with an apostrophe after the "s") as in something belonging to the weldors collectively:D Maybe they did go to Pekin High School. You would at least think the sign company might have asked them if they were really sure they wanted the error out front for the next few decades.

Back on topic. I watched the construction guys working on a new recreation center building here on our campus. The pool is basically in a glass-walled building and the structure that will hold up the glass is galvanized, presumably to deal with the corrosive nature of the chlorine. they had some decorative arches to tack weld and they clearly ground it clean first. They later touched up with cold galvanizing spray which is basically paint with huge amounts of zinc particles. I own several cans and the stuff is quite heavy. I would think that once ground clean, you are doing typical mild-steel welding and that this is the way to go. Better not to make zinc fumes than to worry about how to avoid them.

Paul

Mosside
05-23-2008, 12:28 PM
I have always loved welding but I am much more careful than I was when I was young. Just a small smell of galvanized fumes give me a headache. Also I have noticed how many of the professional welders have in my area have died young of cancer. Not a career I would suggest to anyone. :(

Doug

Tony
05-23-2008, 01:10 PM
ever stop and think of how many retired weldors you know?

I dont know of any -- maybe there aren't any?

On top of all the hazards, most .. come to think of it... ALL
of the weldors I know smoke. Fair bit of 'em drink too.

Its quite a combination.

Over the years I've become quite sensitive to welding fumes.
They don't bother me -- I can keep right on welding through
that toxic smoke cloud -- but I have more regard for my
health and try to avoid it.

In fact, anytime I can tig something -- even if it takes a bit longer --
I do. The process isn't any healthier but good tig
welds require rigorous cleaning so you get rid of most of the crap
you usually stick over: paint, oil, grease, dirt, zinc, etc.


-Tony

madman
05-23-2008, 05:24 PM
Well those galvanized tips sure helped out. Thanx Everyone. Now to build a galvanized fence with 6 4 inch tubes and all the rest 1.5 inch dia. I wondered if fish mouthing the ends to butt up against the other tubes is recommended or just flatten the tube end and weld it against the larger round section ?? Ideas??? Thanx Mike

A.K. Boomer
05-23-2008, 05:50 PM
ever stop and think of how many retired weldors you know?

I dont know of any -- maybe there aren't any? On top of all the hazards, most .. come to think of it... ALL
of the weldors I know smoke. Fair bit of 'em drink too.





I know of one guy in the local area who has been welding for many years (decades) He's got some kind of rare from of bone cancer, I definitly think the fumes are bad news, he does not smoke or drink



In fact, anytime I can tig something -- even if it takes a bit longer --
I do. The process isn't any healthier but good tig
welds require rigorous cleaning so you get rid of most of the crap
you usually stick over: paint, oil, grease, dirt, zinc, etc.


-Tony



Actually the process of tigging is much healthier if your comparing it to flux rod stick or flux core mig, I really dont know the composite of flux fumes but im pretty sure its a far cry from aromatherapy

doctor demo
05-23-2008, 06:46 PM
Well those galvanized tips sure helped out. Thanx Everyone. Now to build a galvanized fence with 6 4 inch tubes and all the rest 1.5 inch dia. I wondered if fish mouthing the ends to butt up against the other tubes is recommended or just flatten the tube end and weld it against the larger round section ?? Ideas??? Thanx Mike
I/ WE try to use black pipe as much as possible, but every now and then galv. is required. WE use a notcher in the ironworker on every piece practical, all the odd stuff gets fitted by hand with a portaband or 4'' grinder, it realy makes the finished product stand out from all the other hackers .
As far as the fumes just hold your breath:D it keeps the lungs clear and helps teach you to weld faster:D .
If you want to try the milk trick afterwards cut the milk 50% with whisky it will go down better. ( outside up wind, or resp. a must!)


Steve


P S if you use a holesaw in a mill or drill press that works ok iif you don't have awhole truckload to notch.

snowman
05-23-2008, 06:48 PM
I haven't tried it, but I've heard that if you use a vinegar soaked rag, you can actually dissolve the zinc off the steel prior to welding

rollin45
05-23-2008, 07:32 PM
I've been welding for 32 years on the job, plan to retire next year, no health issues to speak of.
For future reference:

Galvanizing can be taken off with a grinder and a bit of of hand soap with the grit in it,, JoJo or whatever its called. The liquid hand soap that has some grit, just splash a bit on the surface to be welded, then use your angle grinder ,, it is amazing ( I didn't believe it either) it cuts the galvanizing better than anything I've ever tried.

I've welded galvanized pipe, plate, angle etc. over the years, avoid the fumes as best you can.

rollin'

speedy
05-23-2008, 08:36 PM
like the others said, remove the zinc before you weld.
an option to grinding is muriatic acid. stand the pipes up
and soak the last 1" or so -- it comes off relatively fast..
just to be safe leave it outside overnight (fumes).
you'll have to spray it again once you're done or it'll rust of course.-Tony

Agreed. I have a container of old battery acid (sulphuric) specifically for that purpose. Clean metal makes the job easy.
When I was younger, I had a Summer job mig welding galvanised trampoline frames for Mr Slack. Dozens of the buggers every day:eek: . No ventilation eccept for the open rollerdoor; I can still remember(?) the taste now.



If you want to try the milk trick afterwards cut the milk 50% with whisky it will go down better.
A2 milk though and good quality whiskey, not that bourbon stuff:D

mwechtal
05-24-2008, 01:02 AM
I remember my Dad welding up a bunch of galvanized. Since there was so much, grinding it off was too much work.

Well, the symptom I remember the most was the trap door trots that Dad got. For about 2 days he was one sick puppy.

I don't think he has ever welded galvanized since without grinding it off.

Don't breathe the fumes!

Mike

Swarf&Sparks
05-24-2008, 01:12 AM
Whilst I agree with the above posts re acid (I do the same myself) just remember that the gas evolved is hydrogen.
Further to that, when the acid is no longer active, you have ZnCl, or killed spirits, AKA soft soldering flux :D

torker
05-24-2008, 07:57 AM
I wondered if fish mouthing the ends to butt up against the other tubes is recommended
That's where an abrasive chopsaw comes in handy. Make a "point" on the ends of the pipe (two cuts) @30 degrees each and you have a perfect notch.

Pete H
05-24-2008, 10:12 AM
Zinc fumes are BAD stuff... although not as bad as cadmium fumes.

An old bud of mine, now about 70, who welded a LOT of galvanized in his younger days, is pretty nearly totally disabled from chronic respiratory disease (I guess that's what they call it when you can barely breathe, but there's no clear cause).

Guys who cast brass used to get what they called "bell-founder's ague" - symptoms just like 'flu, plus the "Hershey Squirts", for a day or two. I found that out AFTER I did the same to myself, burning "decorative colors" onto a braze-coated sculpture. Needless to say, that was the last time I did that.

Back to cadmium... it's why you need to be so careful with silver solder (a lot of which contains significant amounts of cadmium). While it's rare for zinc fume to kill you after only one exposure, cadmium oxide is known to do that. So by extension, working with cad-plate takes extra caution too.

Maybe nowadays, with anti-inflammatory drugs and oxygen, they could keep you going long enough to heal, but I sure wouldn't want to live through that.