Pipe Welding video using downhand - Downhill welding will get you fired on most Nuclear plants. But for Pipeliner welders, its the Shizz.
Welding downhill is what they do. All day.
Speed and production needs forced pipeliners to develop welding procedures that are fast and still meet code requirements. (even though some codes are a little loosey goosey)
If you watch the video closely you will see that this guy is carrying a hot puddle. there is no real worry about lack of fusion or trapping slag.
Downhill welding with 7018 or 6013 would be something scary. But using a 6010 with plenty of amps and good technique makes for a sound weld that is done quickly.
The one thing you can take away from this video that works for downhill or uphill welding with stick is that this welder does not chip slag in between rods. He doesnt need to. What he is doing is getting right back into the puddle before it has a chance to cool. Its almost still cherry red when he hits it with another rod.
Thats something I learned from an old timer a long time ago and have used the trick for years because it works. You learn to be like Robin Hood with a quiver full of arrows. You finish with a rod, squeeze the stinger and drop it while loading another sitck and baam! back in the puddle you go.
No chipping...no brushing..just welding. It works much better than stopping and chipping and there is a better tie in because its still hot.
Typically the fit-up is as follows:
35-40 degree bevel on each pipe, 1/8" gap plus or minus 1/32". 1/8" land plus or minus 1/32"
The bevel is pretty self explanatory, and so is the gap, the land is the flat area that is ground on the sharp edge of the bevel. Welding uphill requires a land. Welding downhill usually requires a much smaller land.
Pipeliners used to say "a nickel and dime fit" and I am pretty sure that meant a dime for the land and a nickel for the gap. In the "real world" the gap and land can vary a lot and pipe welders, whether welding uphill or downhill, are expected to be able to compensate. But there is a limit to how much you can compensate without sacrificing quality.
This is where being willing to be perceived as an ass sometimes really comes in handy. Making the fitter grind more to make the gap more consistent is sometimes not the popular thing to do.
Telling the foreman you need to grind the tacks and start over because the fit-up has too much hi-lo to get even penetration causes heartburn too. But sometimes that is just what is required...for you to step up and Just tell the foreman that the welding rod is not a magic wand that cures bad fit-ups and uneven gaps. You can work some magic, but getting a good fit up is where the magic starts.