Pipe Welding on Steel

Don't get hung up on clamping pressure. Tighten enough so it doesn't fall off. On the joints grind away the mill scale about 1/2 inch past the edge would help before welding. The mill scale can add a lot of contaminants. As mentioned before the gap between the 2 faces should be the electrode dia. being used for the root pass. The face of the bevel would be the rod dia. used for the root. Our high pressure welders used 6011 for penetration Then grind out any flux or crap in the weld., Next was a pass of 7018 as the filler, then a 7018 cap.
To set your gap between the pieces use an electrode that your going to use for the root pass probably 3/32 knock the flux off and and sandwich between the pieces, then tack weld to hold., then remove the spacers. This maybe difficult to do horizontally with one person , so set everything up vertically, let gravity do the work.
Just a note if your welding on your lathe be sure the welder ground is on the work, and not on the lathe, you don't want to pass current thru the lathe.
 
aliva said:
Don't get hung up on clamping pressure. Tighten enough so it doesn't fall off. On the joints grind away the mill scale about 1/2 inch past the edge would help before welding. The mill scale can add a lot of contaminants. As mentioned before the gap between the 2 faces should be the electrode dia. being used for the root pass. The face of the bevel would be the rod dia. used for the root. Our high pressure welders used 6011 for penetration Then grind out any flux or crap in the weld., Next was a pass of 7018 as the filler, then a 7018 cap.
To set your gap between the pieces use an electrode that your going to use for the root pass probably 3/32 knock the flux off and and sandwich between the pieces, then tack weld to hold., then remove the spacers. This maybe difficult to do horizontally with one person , so set everything up vertically, let gravity do the work.
Just a note if your welding on your lathe be sure the welder ground is on the work, and not on the lathe, you don't want to pass current thru the lathe.
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Great tips! I wouldn’t even gas weld on my lathe.
 
b4autodark said:
Looking much better! I see you finally took the suggestion I made in my 4th post about setting the coupons in an angle iron, the channel iron you are using is fine as well.

You will not control your undercut as effectively by turning down your amps as you will by slowing down your travel speed and depositing more filler metal. Also concentrate on keeping a short arc also, long arc draws more amps and makes the puddle harder to control. Get the amps set and leave it alone or all you will be doing is constantly adjusting amperage.

On your hot pass strike an arc in the center of the bevel, establish a puddle, move the electrode to one side of the bevel and move it up and down t the distance of 2 rod diameters, move to the other side of the bevel and repeat the motion. Don't pay any attention to the center of the puddle as it will take care of itself, you will find this easier when you get 3/32'' 7018. As I've said before the 1/8'' 7018 is to much rod for the bevel.

You are definantly making progress.
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Thanks for the tips. I have about 10 lbs. of old 3/32” 7018AC that I need to use up. I run every single class of electrode at DCEP.

Once I use up all of the mostly cheap and old electrodes that I have in my possession, I am going to buy the proper size & class of Lincoln electrodes. For example, this E6010:

Fleetweld® 5P+

Fleetweld® 5P+ from Lincoln Electric is first choice for pipe welding, and vertical-up and overhead plate welding.
m.lincolnelectric.com m.lincolnelectric.com

Hopefully Lincoln Excalibur is a good choice for a 7018 on pipe because that rod is so nice to work with.
 
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An other thing that should be mentioned is, keep your rods warm, especially 7018 as it's a low hydrogen rod and it will suck moisture from the air.
If you can get a rod oven, set the temp to 150F. Keep all your rods in the oven, 6010, 6011, 7018, 7024 even SS 309, 316L.
Only take enough rods from the oven that you will use in roughly 1/2 an hour. If the rods are in a sealed box from the supplier they don't need to be heated to drive the moisture out. Once the pack is open then they should be kept in an oven before use. 1 hour at 150F would do.
By doing this you'll get the best possible results, if you making test coupons. A warm rod will flow much easier, try it.
 
aliva said:
An other thing that should be mentioned is, keep your rods warm, especially 7018 as it's a low hydrogen rod and it will suck moisture from the air.
If you can get a rod oven, set the temp to 150F. Keep all your rods in the oven, 6010, 6011, 7018, 7024 even SS 309, 316L.
Only take enough rods from the oven that you will use in roughly 1/2 an hour. If the rods are in a sealed box from the supplier they don't need to be heated to drive the moisture out. Once the pack is open then they should be kept in an oven before use. 1 hour at 150F would do.
By doing this you'll get the best possible results, if you making test coupons. A warm rod will flow much easier, try it.
Click to expand...

I need a rod oven!
 
After watching a lot of YouTube videos, I have made some changes:

(1) Confirming: no 7018 downhill,

(2) 6010, 7010 or 8010 can be downhill, but maybe a little better to run uphill,

(3) Definitely feather the tacks & tie-ins with a stone disc. Not a bad idea to wire wheel finished beads for the purpose of slag removal,

(4) For roots: after tack welding, I can position the feathered tack at 12 o’clock and run the bead downhill, hopefully getting down to 6 o’clock, and ideally just a little past 6 o’clock. Same on the other side, but best not to have the tie-in at 6 o’clock. So basically I will be working from 12 o’clock to 6 o’clock. All of the tack welds get consumed in the root bead.

(5) Maybe bend the 6010 rod in the root while it is burning. Must have 100% pen on the inside & no undercut.

This is the third iteration of my fixturing:

58A939D2-8BF5-469E-84CC-B5E18BC5DFC9.jpeg

BA47E9CE-C37D-4312-AA45-C6FD32FCF192.jpeg
 
Looking better! Regarding rod ovens, do not store 6010 in them. 6010 electrodes need moisture, there have been times I've dipped them in water if they were to dry. The others yes, 6010 no, just keep them on the shelf.

You can run a downhill root if you want but most tests require an uphill one. We never ran downhill roots on any pipe under 12" diameter. If you do, watch your rod angle and keep ahead of the slag.
 
b4autodark said:
Looking better! Regarding rod ovens, do not store 6010 in them. 6010 electrodes need moisture, there have been times I've dipped them in water if they were to dry. The others yes, 6010 no, just keep them on the shelf.

You can run a downhill root if you want but most tests require an uphill one. We never ran downhill roots on any pipe under 12" diameter. If you do, watch your rod angle and keep ahead of the slag.
Click to expand...

Thanks. I will run my 6010 uphill. I am only using 6010 for root welds, by the way. Hot, fill & cap is 7018.

I have some quality 7010-A1 on hand. I could use that for hot passes.

I also have some 1/16” 7014 & 6013, but I will probably use those for other projects.
 
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