Downhill tig ?

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ok, so im testing a steam/ condensate system I finished today, all "small" steel pipe, and notice a leak from the guy who started it on one of his 2" s/w couplings.he tigged all his pipe, some with what looked like 309 (steel pipe remember) and some with what looked like 70s#. this coupling looked like done with 70s#, and downhill. I grind his welds out a little bit and proceed to fill with 7018 as stick is my preferred weapon for steel, to find a huge void in the "root" of the socket-weld. . . . .there was only fusion on the toes of the weld, as in on the outside edge of coupling, and the very edge of weld at pipe. I do a lot of stainless tigging, but am not too fond of using it on steel because I catch myself spending waayyyy too much time cleaning things. I mainly run up-hill because that's just how im used to looking at things and it makes more sense to me, but do admit to tigging down occasionally if the position REQUIRES IT. I never gave much thought to a difference in weld fusion.so, question! is tigging downhill an absolute no-no? or is it something else he may have done wrong like not cleaning? one other thing that crosses my mind is root pass?? I rarely run one on 2" socket weld, tigged or not and know for sure he never does. could that be the culprit?Last edited by 92dlxman; 01-09-2014 at 07:03 PM.bosses stuff:trailblazer 325maxstar 200my stuff:sa 200fronius transpocket 180100 amp Lincoln w/f97 f350 DITKevin
Reply:somebody has to know! how do YOU do it? im really curiousbosses stuff:trailblazer 325maxstar 200my stuff:sa 200fronius transpocket 180100 amp Lincoln w/f97 f350 DITKevin
Reply:Well, I'm not sure it applies, as I mainly weld tubing, or various types of architectural materials, or the odd piece of plate, etc., but I weld tubing in any position, going any direction and have never seen it behave one whit differently, no matter the position.Miller Dynasty 200 DXMiller CP-300 with 30A feederHypertherm Powermax 900Oxy-fuel w/Harris torchesScotchman Glide-in bandsawMonarch 10EE latheEmi-Mec Autoturn latheDeckel FP2NC milling machinePro-Tools 105 Bender
Reply:thank you for replying. I see lots of people run in a lot of directions and always assumed it was ok, but this weld was complete garbage once I scratched the surface.he is also somebody that RARELY changes/sharpens tungsten, no matter what shape it is in. maybe since his heat is never focused he didn't get good fusion? the weld looked ok on the outside, im just intrigued by how crappy it really was. .. . .fooled me that's for sureim mainly concerned about it because well, I have crappy days too where I may run myself out of tungsten, too rushed to stop and sharpen (I NEVER let them get past the point of looking somewhat pointy), or may need to downhill something because of obstructions, or whatever.I just don't want to repeat the same thing he did, especially on steamLast edited by 92dlxman; 01-09-2014 at 09:27 PM.bosses stuff:trailblazer 325maxstar 200my stuff:sa 200fronius transpocket 180100 amp Lincoln w/f97 f350 DITKevin
Reply:Originally Posted by 92dlxmanthe weld looked ok on the outside, im just intrigued by how crappy it really was. .. . .fooled me that's for sure
Reply:I think it's probably a lack of preparation that created the problem and not the downhill tig welding. Or the guy is just garbage.
Reply:Pretty common in the pipe welding field to have a two pass requirement on all socket welds. That is, if you have a weld procedure and any kind of inspection going on. You found out why...leaks. We are required to run two passes where I'm working.Your weld procedure will tell you what you are supposed to be doing. Sure you can weld TIG downhill and get by if you know what you're doing. Never seen a downhill TIG weld procedure, though. Sometimes you HAVE to do it, but you can't one pass it all cold and with a dull tungsten and expect it to hold pressure.
Reply:Originally Posted by TimmyTIGPretty common in the pipe welding field to have a two pass requirement on all socket welds. That is, if you have a weld procedure and any kind of inspection going on. You found out why...leaks. We are required to run two passes where I'm working.Your weld procedure will tell you what you are supposed to be doing. Sure you can weld TIG downhill and get by if you know what you're doing. Never seen a downhill TIG weld procedure, though. Sometimes you HAVE to do it, but you can't one pass it all cold and with a dull tungsten and expect it to hold pressure.
Reply:I'm sorry to hear that.  That sounds frustrating.  Not doing something fundamental, such as prepping and maintaining one's tungsten, sounds like someone who has a real lack of respect for their profession.  To me, that would be like a plumber showing up to install new pipe with nothing but a pair of slip-joint pliers.  If you stay at your job, I hope you can rise above the flotsam, keep your dignity, and keep learning and improving your skills.Miller Dynasty 200 DXMiller CP-300 with 30A feederHypertherm Powermax 900Oxy-fuel w/Harris torchesScotchman Glide-in bandsawMonarch 10EE latheEmi-Mec Autoturn latheDeckel FP2NC milling machinePro-Tools 105 Bender
Reply:Originally Posted by 92dlxmanprocedure lolthis is what really irritates me about this company. he and I are the primary fitter welder's any more. we were both taught by the same people, (our bosses), and the only reason I have fewer leaks and "do-overs" is because I READ A LOT! procedure is not something they ever talk about within this company and the reason I started this thread was so that maybe I could get some for-sures from you guys and start educating a little bit. im sick of the b.s. welding. I feel like I work for a somehow money-making joke sometimes.case-in-point: one of my first welding jobs (structural) was a beam replacement that supports a large trolley hoist that ran the length of the building. gov. job. some 12"xwierd taper-flange beam.  anyway, I ask super for any specs, symbols, anthing on paper he might have, and he has nothing. "the shop put the proper bevel on it, all you have to do is fill it up." I did, and as a surprise to all of us, here comes an independent weld inspector along with a government entity the next day with ultrasound machine in hand. myself and the other welder FAILED each and every joint. this is normal stuff and when I marched into the office when I got home, red-faced embarrassed mad, management didn't bat an eye, that's just part of it they tell me.this is why we will never be truly competetive