Welding Certification test Q&A and tips and tricks
jwright650
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Heat input (joules per inch) = Volts x Amps x 60 divided by travel speed (measured by in/min)

I suppose there is an "assumption" that a weave (particularly a wide weave) will not have the same "forward" travel speed along the joint, therefore given all other info remaining the same, the heat input increases due to the slower travel speed.
John Wright
AWS Certified Welding Inspector
NDT Level II UT, VT, MT and PT
NACE CIP Level I Coating Inspector
taz
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Most codes allow for variations in the electrical parameters provided you stay within the qualified heat input. So if you could weave that wide and still move fast enough to stay within the qualified heat input you should be ok.
However considering we are talking about SMAW and the fact that most electrodes have a recommended current range it is almost impossible to weave that wide and still be able to move fast enough while making an acceptable weld. You will have to progress at a speed that will lead to an increased heat input.
EN 1011-2 "Welding Recommendations for welding of metallic materials — Arc welding of ferritic steels" states that for SMAW the weave width should be restricted to 3 times the diameter of the core rod. Similar guidelines exist in many companies recommended practices.
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taz wrote:Most codes allow for variations in the electrical parameters provided you stay within the qualified heat input. So if you could weave that wide and still move fast enough to stay within the qualified heat input you should be ok.
However considering we are talking about SMAW and the fact that most electrodes have a recommended current range it is almost impossible to weave that wide and still be able to move fast enough while making an acceptable weld. You will have to progress at a speed that will lead to an increased heat input.
EN 1011-2 "Welding Recommendations for welding of metallic materials — Arc welding of ferritic steels" states that for SMAW the weave width should be restricted to 3 times the diameter of the core rod. Similar guidelines exist in many companies recommended practices.
Will comment more later but we are discussing FCAW not SMAW.
-Jonathan
taz
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Oops.
However the rest of my post applies to all procedures.
Butcher
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I went and preheated the test piece to around 250 degrees, which I hadn't done prior. I noticed no matter how dialed in I felt I had the machine the first weld I layed always had slag that couldn't be easily chipped off. This time there was a slight peeling to the slag of the first weld. The more I filled in the piece the more of a peel I had to the slag. Instead of weaving the root pass I ran a single fat stringer. I was pretty pleased with it minus one hiccup in it which I ground out. I ground on every weld and feel very confident I did well. I ran this around 375 IPM and started at 24 V and bumped it up to 24.5 V after a few passes. When I mig weld I can set the same machine to the same settings and it welds exactly like I expect it to. With this stuff it seems like I use a different setting every time.

My test piece is oversize so I will trim the ends off. Doing this on the last piece saved me from sending in what would have been a failure. The school pays for 3 certification tests, after that we pay for our own. I have a very minor amount of undercut that you really have to look close at to see it is there. I was worried about undercut on my previous piece and measured it and most of it was a 1/64" with none at the limit of 1/32", this is much less. That and I am over the 1/8" limit on cover pass height so I will grind that down also. It seems like I have been on this test for an long time and am ready to move on.

Pictures are of the root pass and finished product. Any criticism is welcome.
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Butcher,
I think you have come along quite well. I wish you the best with this test piece. Keep us posted on your results.
-Jonathan
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What are those ugly little things hanging onto the bottom of that last pic you posted?
Surely you are able to eliminate those ?
Just a couple welders and a couple of big hammers and torches.

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GreinTime
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@AKweldshop I think he mentioned his piece being oversize
#oneleggedproblems
-=Sam=-
Butcher
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AKweldshop wrote:What are those ugly little things hanging onto the bottom of that last pic you posted?
Surely you are able to eliminate those ?
I was starting my stringers on the backing plate so that is where the weld transferred from overhead (doesn't seem like the right term?) to vertical. Unless you mean the two short stringers, that is where I filled in two low spots.
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Butcher wrote:
AKweldshop wrote:What are those ugly little things hanging onto the bottom of that last pic you posted?
Surely you are able to eliminate those ?
I was starting my stringers on the backing plate so that is where the weld transferred from overhead (doesn't seem like the right term?) to vertical. Unless you mean the two short stringers, that is where I filled in two low spots.

I'm talking about those two little stringers that you used to fill the low places, yes.
Bottom line.
They look bad.
Your capping stringers should be one weld from top to bottom.

If you have low places, for gosh's sake, fill them in thru out the fill passes.
You had tons of time to even things out.
Please do not fill the low places on the cap.

John
Just a couple welders and a couple of big hammers and torches.

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AKweldshop wrote:
Butcher wrote:
AKweldshop wrote:What are those ugly little things hanging onto the bottom of that last pic you posted?
Surely you are able to eliminate those ?
I was starting my stringers on the backing plate so that is where the weld transferred from overhead (doesn't seem like the right term?) to vertical. Unless you mean the two short stringers, that is where I filled in two low spots.

I'm talking about those two little stringers that you used to fill the low places, yes.
Bottom line.
They look bad.
Your capping stringers should be one weld from top to bottom.

If you have low places, for gosh's sake, fill them in thru out the fill passes.
You had tons of time to even things out.
Please do not fill the low places on the cap.

John
John,
You made those statements now back them up.

You have forgot that Butcher is welding to AWS D1.1 and he will be turning his test plate in with the cover pass ground down. Why then would it matter what the weld looks like?

There is NOTHING in code that states a weld must be continuous no matter the length of the weld.

"Section 3.7.1 Vertical-Up Welding Requirements. The progression for all passes in vertical position welding shall be upward, except that undercut may be repaired vertically downwards...."

Figure 4.21 Test plate for Unlimited Thickness-Welder Qualification clearly shows the test plate shall be 5" min to which his plates are 6", I know because I provied these particular plates, therefore he can cut off the ends and get rid of those "little ugly things hanging onto the bottow."

If I am incorrect in my reply, please correct me with the code to which he is welding to.
-Jonathan
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Ok,
So technically there is nothing wrong with filling in low places.

But it won't impress anyone.
It's very simple to eliminate them.

IMO.

It was just a tip I was sharing in hopes of helping on a small way.
Just a couple welders and a couple of big hammers and torches.

Men in dirty jeans built this country, while men in clean suits have destroyed it.
Trump/Carson 2016-2024
jwright650
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Butcher wrote: the two short stringers, that is where I filled in two low spots.
As an inspector...I realize that these things happen...you realize that you have a low spot and you fill it in. Good Job!...now before you call me over to inspect the cap, take care of the extra reinforcement(any high places more than allowed in Table 6.1, generally 1/8" max) and all is good. :)

AK was just trying to get you to notice and correct the passes before you get all the out to the cap...but I realize there are times that you may not catch that in time...filling in is acceptable(as long as you correct the amount of reinforcement...aka grinding)

BUT....read on

If this was a performance test...I would ask you to fill it in like you have, and then wait and ask if you can grind it back into compliance. Reason being, grinding may not be allowed on some performance tests(depends on the code the test is being done to). Hope this helps.
John Wright
AWS Certified Welding Inspector
NDT Level II UT, VT, MT and PT
NACE CIP Level I Coating Inspector
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