TIG Welds

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Too cold?Here a few examples of my TIG welds on 3 inch, schedule 10 stainless pipe. I get a variety of shiny colors on top. The inside of the pipe has no burn through and a blue, sometimes dark purple color. Do these welds look too cold? Shouldn't they lay a little more flat and be darker in color? They get tested for leaks at 300 PSI. That is the only test they will receive. But I want them to be as strong as possible and to last a life time.Hope the pic quality isn't too bad. I have to snap pictures sneakily at work Thanks in advance
Reply:1-Apparently there's no sand/grind prep to either piece, not even taking the skin off?2-No pics of the root, but what's shown is a lay rod cover pass over the bevel withvery incomplete root fusion.3-Is there any spec. conformance required?......or just a one time hydro and it's all 'Gud 2 Go'?I'd be more concerned about the lack of root fusion than the colors.Blackbird
Reply:In addition to above comments, I'm confused by the width of the weld.Why is it so wide compared to the bevel?Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:Each piece gets a small 45 degree bevel. They butt right up to each other with no gap. I used a 3/32 rod and I spread probably 1/8 of an inch on either side of the bevel. Is this a bit much? This is my first welding job and nobody really explains much. Just learning as I go
Reply:Is that really 3" sch.10 with threads?  Nice cap, but like others have said, it's the consistent penetration that counts.  Any discrepancies can allow cracks to start.  Forever is a long time.
Reply:Originally Posted by PipeStandEach piece gets a small 45 degree bevel. They butt right up to each other with no gap. I used a 3/32 rod and I spread probably 1/8 of an inch on either side of the bevel. Is this a bit much? This is my first welding job and nobody really explains much. Just learning as I go
Reply:From what I see if there is no gap then 300 PSI should not be any problem at all but are these going to be installed where there is NO vibration?...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:pipes; that appears to be a sound weld. on the outside. it's what's on the inside that count's just as much. what's that look like?i.u.o.e. # 15queens, ny and sunny fla
Reply:I'll try to snag some pics of the inside weld tomorrow at work.MinnesotaDave, I do believe that weld is similar to figure 2. The strange thing is, they do not purge pipe where I work, and they frown upon sugar on the inside of the pipe (since fuel flows through it). Therefore, I can't really get 100% penetration, more like 95%. Is it possible to get 100% penetration with no purge and no burn through?There are probably vibrations, but not many. Here is an example of what I build...That big aluminum vessel is a filter and fuel travels through the pipe. They are airplane re-fuellers.
Reply:This is my first welding job, and I just hope its not going to set me up for failure in the future. I'd prefer learning correct methods now with good penetration to better myself.But, hey, I guess every weld shop has different ways of doing things
Reply:Off topic from my TIG welding dilemma, but here is some fluxcore welding I did on pipe.... I believe penetration is much better with the MIG.On the inside, it doesn't look like sugar, but an even seam all the way around with dark lines on either side.Work requires me to knock off the stop/start with a file. That's what the scuff is you see on that one weld. Makes it look better when painted.
Reply:Originally Posted by PipeStandThis is my first welding job, and I just hope its not going to set me up for failure in the future. I'd prefer learning correct methods now with good penetration to better myself.But, hey, I guess every weld shop has different ways of doing things
Reply:Caps look good
Reply:pipes; you doing ok for your first welding job! did you learn in school or by doing? the only direction you can go from here is up!i.u.o.e. # 15queens, ny and sunny fla
Reply:Baffled by this thread.  That looks like some pretty serious equipment you're putting together.  Is there that much difference between shop and field installations?  I've only worked the latter and around here there would be a strict criteria as to who welds on a project like that.  At the very least, there would be a procedure test required which would answer all the questions about complete penetration.  Then there would probably be at least 10% x-ray requirement.  Definitely purged.  Another test before mig would be allowed.  There was another thread going around where an inspector was concerned about signing off on structural welds without doing a visual.  Seems this is a lot bigger deal considering you can only see the cap.  Root tie-ins are probably the most critical part of the weld.Last edited by OldSparks; 07-12-2014 at 11:08 AM.
Reply:I'm confused as hell as well.  No disrespect meant, but you're learning "as you go" on pipe that carries pressurized fuel to airplanes?Your tig outwardly better than anything I can do, but why would you not purge?  Doesn't look like cheap equipment.