Horizontal Test

By dr3r42 Date 12-27-2006 10:29

I was wondering about the technique used for the root pass on a 1" Horizontal (2G) test using 1/8th 7018 rod. I was told that the gap isn't wide enough to run two stringers (top plate and bottem plate) and that I'd have to weave the first pass (possibly the second as well). I was wondering that since 7018 is a fast fill rod, wouldn't I be running the risk of traping slag, especially when I hold the corner on the top plate ?

they won't let me use 3/32 rod on the root, otherwise I'd run two stringers with that, then switch to the 1/8. I've got no problem weaving on the Verticle up (3G) and even on the root pass of the overhead (4G) portion of the tests, but I was just wondering about the horizontal portion. It's strange, that I've taken verticle and overhead weld tests before but never horizontal (they usually figure if you can pass 3 and 4 G, no use for testing 2G), but this place wants a horizontle test as well. Any help would be appreciated, thanks.

By R. Johnson (**)

Date 12-28-2006 19:32

Is this a plate test with a back up bar? Or is it a open root and they expect you to back gouge the back side? What welding code are you working to?

By dr3r42 Date 12-28-2006 20:25

As far as I know, it's a plate test with a back up strip. I am pretty sure it's an X-Ray test and not a bend. From what I was told it will be similair to the AWS D1.1 (90) structural weld test, except it will be in 2G, 3G, and 4G, rather than just 3 and 4 G. and, like I said, it is an X-Ray and not a bend.

By MBlaha

Date 12-29-2006 02:48

IMHO, i thinkk you would stand a greater chance of trapping slag if you run two passes on your root. May I ask what the allowable root gap opening is? I like to use the widest gap allowable, (usually 1/8") and cheat that to the full limit. I would just use enough weave to make sure you are breaking down the top and bottom edge of the plates. Do the coupons have a knife edge, or a land? Make sure you are running hot enough so you can deposit a light layer on your first pass, but not undercutting the top and leaving cold roll on the bottom. Watch the top and bottom edges of your puddle, not the back as you will see the slag and confuse that with your puddle. Make sure your lead angle and work angle are correct. If you have a chance to practice, do it. Get your machine set to where when you tap your slag when cleaning, it all falls off without having to make it sound like a woodpecker going after a hollow tree. If your slag wants to hang tight, you probably are traveling too fast, or too hot. This is where watching the top and bottom edge of your puddle fall into place. If you can see just when the puddle starts to bubble or lift out, that is when it is time to move to either the top or bottom depending on which edge your filling. When I mentioned slight weave at the begining of this post, what I meant, was just enough to fill both the top and the bottom. Usually not more that the diameter of the rod. If you are running a 1" coupon, make sure you preheat to at least 150 degrees, or what ever the WPS spells out.

Practice, Practice, Practice.

Hope this helps. Good luck

Mike

By R. Johnson (**)

Date 12-29-2006 15:04

If they give you a standard B-U4a joint to weld in the horizontal position, it should have a 1/4" root opening. The smallest the root opening could be is 3/16" and if you do the fit-up as part of the test you are allowed to go to a 1/2" maximum root opening. I used to give this test plate to the welders in the shop and I required a 1/8" electrode on the first two stringer passes. With a 1/4" root opening there is plenty of room to tie into the backing bar and insure no slag inclusions at the root of the weld joint. After the first two stringer passes I would let them use either a 5/32 or 3/16" electrode, whichever the welder was more comfortable with welding. I am sure you will have no trouble taking the weld test. Keep you amps down and lay in two nice stringer passes in the root. Best of luck.

Randy

By vonash

Date 01-15-2007 22:40

I agree with R Johnson.