Pipe Welding on Steel

[erikmannie]

I have made some 4”, 6”, 8” and 10” Schedule 40 pipe welding coupons with a 37 1/2° bevel and a .050” land. This is an easy job on a lathe.

I wanted to go to welding school which had about 40 weeks of pipe welding, but I am going to try to do this at home. Going away to school is expensive and has a lot of unproductive down time.

I welded my first seam today on an 8” coupon. I used a 3/32” gap, 6010 tack welds every 90°, one root pass with 3/32” 6010 at 60A, and then 5 passes of 1/8” Excalibur 7018 (great stuff!) at 110A.

It was rough, but there were some rays of hope.

 

[erikmannie]

The result is obscene, but I will reluctantly upload a photo or three.

2 of my tack welds failed when I welded the first 90°. I had to put it in my hydraulic press and re-tack it (in the press!). This makes the case for better tack welds.

I was only comfortable welding from 10 to 2 o’clock. At 2 o’clock, the weld metal started to drip down. I tried some 7018 vertical up (building a shelf), but the bead was ugly.

With some practice, I will be able to make it happen from 10 to 2 o’clock, but the vertical and overhead is out of reach at this point.

 

[erikmannie]

I have stick welded a lot of .050” muffler tubing with 1/16” 7014. I got that down, although sometimes I would blow holes and have to fix it with 7024. I would rotate it up to 12 o’clock to do this repair.

Now I will only use 6010, 7018 and 7018AC. I do ALL of my stick welding on DCEP.

 

[erikmannie]

I think I might do a lot of work at 10 to 2 o’clock and try to extend that as I am able. I am also going to change the gap to 1/16”.

I have watched so many pipe welding videos on YouTube.

I might also change it to 3 passes of 6010 before I switch to 7018. I feel way more comfortable welding with 6010.

I won’t be working on much else until I get this down. Pipe welding is super fun because there is a great deal of arc time and opportunity to practice vertical up.

 

[matthewsx]

How do you get to Carnegie Hall?

 

[erikmannie]

How do you get to Carnegie Hall?

Practice, practice, practice. I have nothing else going on.

 

[Cadillac]

Looks like you could be alittle hotter. If doing a lot of pipe you might want to look at some pipe roller stands. Fairly easy to make and will keep you under the hood longer. Looking good!

 

[erikmannie]

In my excitement to get welding, I skipped over the part where I plan the work.

I did a lot of reading last night, and my guess on how to do it (despite watching hundreds of YouTube videos) was more wrong than right.

I am going to take it one step at a time, and just do a single, hopefully correct root pass on all of the coupons first.

So far, I gather that a “nickel” land will serve (I made the lands .050”), and the gap should be one electrode size smaller than what is being used. I have 3/32” 6010 so the gap will be 1/16”.

 

[erikmannie]

I also learned that you can go downhill with 6010 due to it’s fast freeze characteristics.

Speaking of only the 6010 root now, I also read:

(1) you need 100% pen, so you need to get a keyhole immediately and never lose it, and you are only working to fuse the lands. No attempt is made to weld on the bevel.

(2) you are basically to jam the electrode into the groove. The result should look like it was welded from the inside. Start with a 90° electrode angle, and adjust that only to avoid leaving behind a hole. Alternatively, you can turn down the current so as not to get holes.

(3) to reiterate: a single pass only of 6010. After that, the hot pass for which 7018 or the like (fast fill, low hydrogen) is recommended. Any 6010 in the bevel is unwelcome because that gets you wagon tracks, so best to grind that down so that the hot pass goes onto a surface free of convexity.

(4) a 1” long tack weld every 120° is good.

(5) obviously, the electrode is equally biased between the 2 coupons. If you want to, you can keep the electrode at a 90° angle if you whip and pause (as opposed to getting your current set perfectly and then just dragging the rod). One of the people online said to maintain the 90° during the whip and pause (i.e. move the electrode holder back and then forward). I do whip and pause, but I was changing the angle in doing so.

(6) bad things happen when you long arc, so jam it in there.

(7) move fast.

(8) you need to take the time to get the settings right. The only settings on my machine are current and DIG. I know to set DIG at 30% for 7018. I tried 60% for 6010, and I liked that.

 

[erikmannie]

For the record, I am working on 6010 root and 7018 cap. I fully understand that successful pipe welds have been made using every other electrode type and combination possible.