Welding Tips and Tricks

I took a 2G and 3G test on 1/2" carbon steel with a backing plate and failed both of them for lack of fusion (tested via Xray). I didn't get any more details than that. I was running .045 dual shield wire with 75/25 gas at around 40 cfh. For the 2G test I was at 25.3 V, 280 IPM and 195-207 amps. For the 3G I was at 25.5 V, 250 IPM and about 180 amps. Once or twice I had a tight crevice between two stringers that I ground out and opened up so I could easily burn in and fill the area, so I don't think that was an issue. When I lay my root pass in I make sure the piece is good and warm (maybe 200-250 degrees) before I lay it in. I generally keep my electrode straight in rather than a push or pull angle.

Any ideas on where I could have went wrong?

My gut reaction is that the current (wire speed) is low for the position. It's been years since I've welded .045 dual shield, though... I'm thinking 300+ ipm at that voltage, if the WPS allows.

Steve S

I think your 3G setting are ok. Did you do any destructive testing before the test? My first thought is you are not holding the sides long enough? The film will tell you what you need to know.

Don't beat yourself up too bad man, lack of fusion is generally used by xray techs to mean a bunch of things. A lot of times all it was was a shadow in the film, sometimes from the cap. Saying that, I usually run my fc with more wire than that. I like it hot though, so I usually run more voltage as well. Not knowing which pass busted you sucks, usually its on the root so my advice would be to make sure you have a little bigger gap and landing to make sure you tie in the backing plate.

The old rule still applies - in doubt? Turn it up, tie the sides and let the middle take care of itself.
Lack of fusion is plain as day on an x-ray, not a shadow and any x-ray tech worth his (or her) salt will be able to see the difference.

I remember always increasing wfs in 4G position. start in flat settings. . 3g was same or close to voltage but lower wfs.. 4G was same voltage as flat but more wfs. it worked well for me and was easy to jump from position to position in a production environment

Fluc core and solid wire I crank it up as far as I can. All scale cleaned off and in between passes wire wheel and quick grind. Mig has more chance for porosity than stick IMO. I'd be willing to bet your wire speed screwed you. At 25v I'm running 350-400 wire speed. Root pass needs to burn in hot if your using a backing strip. I remember when I did mine a good 1 inch area was glowing orange when I lifted my hood. I definitely overheated it but I wanted it to burn in and fuse solid. Tested out fine.

I think that the guys who mentioned "hold the sides" have it nailed down as to the culprit. You have to, have to, have to hold the toes of the weld! Generally, I get about everyone in my class will pass the SMAW 3G test, but about half will fail the 3G vert. up GMAW test.They fail because they don't hold the sides long enough.

The big thing I see is what I call 'bouncing'. This is where the welder holds one side of the V-groove well, and does not hold the other side equally. Now, the welder is sure, the welder will swear and testify that they are not 'bouncing' but they are doing it.

Have someone watch you and verify on a practice plate make sure that you are holding sides long enough.
Gary

I passed 2g 1/2" plate 3/8" backer asme fcaw, 3g and 4g 1" plate 3/8" backer aws d1.1 fcaw @ 25v 250 wfs no pre heat x-ray and bend test on all. 1/4" root gap. when I run the root I use zero side to side movement, 90 degree to the plate travel slow enough so the puddle flows into the sides and fuses without any manipulation. very slight weave/whip all subsequent passes. I do a lot of q.c. (non destructive x-ray tested) fcaw work and never failed using this technique. esab high nickle wire is what we use required by bp in the north slope oilfield.