I believe there is a place for any process. I think mig is faster when prefabing pipe but one of the things you have to look out for is the root. I've seen mig welds slam it together with no root to get ot done fast. I'm mainly a stick welder but our comany is switching the prefab to mig. The guy training me said mig is a cleaner process is this true? I went along with it because I like my job. However I don't think mig is practical for tight position welds in the field because the starts have to be perfect. If it spaters in a tight spot your f***ed. With sick you can burn it out. I know there are more reason why rig hands us acr instead of mig. I would like to know more. We have a golden arm that loves mig, he is driving a bus over everone. A squirt gun may be faster but its not always the answer. I need to know the facts.
I know what you mean I work welding aluminum and we use both mig and tig process and I know everyday when welding I'm always crabing some scrap plate to dial the machine in for that thickness and sometimes i'm like why the hell don't they just tig this but seems like it easier and you can control the heat so much easier then with mig you got to have the heat and wire dialed in just right to get it to weld good. I have always felt tig was easier then mig. I feel the same way I think stick is probally a little easier then mig as well but these companys want speed so they choose mig.
I've heard some guys say oneday all these mig welds are gonna fall apart well no if the machine is dialed in right that is the key word, they will make very strong welds but I personally don't feel like there easier to weld with well maybe easy to weld but not easy to dial in perfect.
I'm young so I guess I still got alot more experience I need to gain so I guess I'll answer these questions 5 years from now but for now no I don't like mig
and yes mig is cleaner then stick or fluxcore
Is GMAW cleaner than SMAW? Well does GMAW produce slag? Of course it's cleaner.. This doesn't mean that GMAW can't produce defects if proper process control is not in place..
Can GMAW make poor welds if the operator "slams it together to get it done fast"? of course... Same with SMAW.. If you don't follow procedures things go wrong no matter what the process. GMAW needs tight controls to produce good roots.
SMAW for in house fabrication of any kind (pipe or structural) has pretty much gone by the wayside all over the country. Other processes (including GMAW) can do it better and faster.
You don't think GMAW is practical for tight positions in the field... Of course it isn't... How do you get GMAW up a 75 foot scaffold to do rows of pipe on tight centers? It's impossible... But you diddn't mention in your original post that GMAW was being brought into the field.. only the shop.
Don't fight it.. Just learn what they want you to learn.... While your learning have your practice work destructively tested whenever you can. Learn how to make the best welds with GMAW...
Teaching a new process that can do the same amount of production in about 1/3 the time is not throwing you or anybody else under the buss.. it is saving the company... The shops that stay with old SMAW technology where other processes have been more productive for 20 years will die in this tough market.
I consulted for a place that was using scratch start GTAW on 1/4" stainless structures and pressure vessels... They fought GMAW-P for the stainless fabrication with hammer and tongs... They fought giving the pipe welders thumb controls on their GTAW torches... "I've been welding this way since 1972 and have never busted an X-ray" Well that may be true.. But it doesn't mean that the learning curve and ease of production can't be improved by taking advantage of new technology. They wouldn't give up GTAW inside of large truck tank barrels because they could not get spray transfer GMAW to properly fuse even with the tank rolled. When we setup GMAWP with a Spool gun they quadrupaled production inside those tanks with fewer defects than GTAW.
Don't be afraid to change. If your a good stick welder than GMAW will be a snap to learn.. Just get a textbook so you can understand the fundamental theory behind Voltage and Amperage relationships. CC welding (stick/Tig) and CV welding (GMAW/FCAW) are very much different when it comes to manipulating the puddle with the gun.
+1 to what lawrence said
as a welding engineer for shop and production I tend to look to the process that is fastest, easiest and produces the lowest defect rate. It changes depending on the situation but I personally believe GMAW is one of the easiest processes to learn and is very economical and fast which probably helps attribute it to being the most common welding process in the US.
Also when I was a welder I always liked having another trick in my bag and learned any and all processes I could. I think a lot of people go by the "if it isn't broke don't fix it mentality" and are hostile to change and like to hold onto old processes like scratch start TIG or running 75/25 for GMAW because they aren't aware of the better options.
I'm the only weirdo who doesn't like the aluminum mig LOL Those dam things break down alot but when they work they work
I hate those squirt guns with a passion but they are becoming the norm in the fab shops, be it hard wire or fcaw/dual shield. They can put a gorgeous bead in if they're done right. They can have just as many defects as a stick weld too. One of the biggest problems I'd think is that you could get alot of porosity if the shielding gas isn't right and you could also get some cold lap/LOF. The only thing that youd be hard pressed for would be slag entrapment. I know hard wire doesn't have slag but the "slag" I'm talkin about is if the welder is trying to carry so much metal that he traps some silicone in between passes cause he didn't brush between them. Kinda far fetched but could see it happening from somebody that aint payin attention. Most your fab shops tho will run mig bead, hot, an maybe a fill then sub-arc the rest on bigger components cause the deposition is so high but use mig for all the rest.
Well guys, I`ve been reading all your posts. I don`t weld pipe but if I was to hire a guy to do what I do - steel fabrication and equipment repair - then he`d better come prepared to do a lot of MIG welding. Otherwise it`s going to take him three times as long to get the job done. And the quality is surely there as well. Last year I bought about five hundred pounds of wire and maybe forty pounds of sticks. I realize that MIG isn`t the only process but it seems perfectly suited for what I do. Sure I could do the same jobs with sticks...but who`d hire me?
Almost everything that is prefabbed comming out of my shop is migged unless specified by the WPS. Alot of mig stringers with stick cap and tig stringer with stick cap. If it can be rolled out it will be mig stringer with Pulse Mig fill and cap most of the time. What Im getting at is if you do this type of work you better crank out product with all processes or your going to be left in the dust by competition. A welder needs to be able to do it all and be good at it all because different situations call for different processes. As far s the mig off the rig, thats not going to happen very often unless Im backed up to a shop some where I can get my suitcase out. I do tig alotoff the truck but you have to have a hooch to block the wind. I have run FluxCore off the truck on some pipeline work and heavy equpment repairs but, like I said before gotta be able to put out welds with all processes effectively and productively. Just my opinion......
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