I was hired into the quality group at a company alongside three other CWI's last October. I'd been asked to do a lot of paperwork type activities until this last July when they needed
that fourth CWI on the floor.
I seem to have put the floor into shock... for example: for inspecting parts to the tolerances on the drawing and writing a nonconformance when it's out of that tolerance range. The other inspectors had been trying to convince me to apply "common sense" to let the parts through anyway, even if that meant the associated paperwork doesn't line up with what the physical part is. I'm still the same person I was when I came through the code clinic, you can guess how the workplace has become increasingly hostile towards me yet again.
I write to ask two quick questions to verify if my thought process is correct if you have a moment:
1. Detailed vs. fit-up tolerances. The code and chatter on the AWS forum eludes to fit-up tolerances applying to the as detailed one. So if detailed gave me +10 degrees, fit-up would give an additional 10 degrees - stacking the two together. I thought I distinctly remembered from the code clinic that the tolerances do not stack, but that both apply to the original, 45 degrees for example. So the max. would be 55 degrees end of story. I am not able to find the support in the code for that and was hoping to double check my memory on that.
2. Starts and stops of intermittent welds. It seems that the D1.1 exception for filling a crater to the full cross section outside of the intermittent area has been taken to the level that the code doesn't apply outside of the intermittent length. Doesn't it still say we should have complete fusion, and smooth transitions - not worms at the start and stop of those?
Just thought I would check in to make sure I'm not getting off base here.
Let me get right to answering your questions...
When it comes to “AS Fit-up” vs “As Detailed” tolerances, during the seminar I will always emphasize, “For the purpose of this test, do not stack the tolerances.” I’ll then go on to say, that may happen in life, but do not do it for the purpose of this test.” CWI’s should never use the “As Detailed” tolerances... only the engineer/designer of the part/joint should. Let me give you some examples:
1.) A Designer/Engineer calls out a B-U2a with a 45 deg Groove angle. The shop floor/Welder/CWI can apply the “As Fit-up” tolerances ONLY and the Groove angle can now range from 40-55 degrees.
2.) A Designer/Engineer calls out a B-U2a with a 55 deg Groove angle (he/she applied the “As Detailed” tolerances). The shop floor/Welder/CWI can apply the “As Fit-up” tolerances ONLY and the Groove angle can now range from 50-65 degrees.
3.) A welding symbol calls for a 30 degree V-Groove on a Butt Joint. The shop floor/Welder/CWI can apply the “As Fit-up” tolerances ONLY and the Groove angle can now range from 25-40 degrees.
4.) A welding symbol calls for a 35 degree V-Groove on a Butt Joint (engineer applied the “As Detailed” tolerances). The shop floor/Welder/CWI can apply the “As Fit-up” tolerances ONLY and the Groove angle can now range from 30-45 degrees.
All those scenarios are perfectly acceptable for that joint type. The Designer/Engineer has one type tolerance they design within, and the shop floor/Welder/CWI have a different tolerance they work within.
Now let me give you some scenarios that DO NOT WORK:
5.) A Designer/Engineer calls out a B-U2a with a 45 deg Groove angle. The shop floor/Welder/CWI applies the “As Detailed” &“As Fit-up” tolerances and the Groove angle now ranges from 40-65 degrees.
6.) A welding symbol calls for a 30 degree V-Groove on a Butt Joint. The shop floor/Welder/CWI applies the “As Detailed” & “As Fit-up” tolerances and the Groove angle now ranges from 25-50 degrees.
The shop floor/Welder/CWI should never stack the tolerances on their own. Again, one set of tolerances is for the Engineer/Designer, another is for the shop floor/Welder/CWI.
Clear as mud, eh?
As for the intermittent fillet weld...
The crater can remain unfilled (weld is undersize) as long as the crater falls outside the required weld length. All other acceptance criteria have to be met for the entire weld length (including the crater). So unacceptable contours, unacceptable undercut, unacceptable porosity, cracks, overlap in the crater would still render the weld “Unacceptable”.
As for your work environment...
I took a position once and was over 5 CWI. In my first week I found that all Welders were qualified with FCAW but 75% of the welding was with GMAW. I called each into my office to ask about this. The responses were pretty lame, “That’s what we’ve always done.” “You can’t change things around here.” “There really no difference.”
Don’t Be That Guy/Gal! Stick to the requirements and intent of the code, and when there’s a disagreement don’t argue, “Put your finger on it”. Better to have integrity then a stable job (I’m sure some would not agree with that line). My unstable work history has worked well for me.
I hope that helps. Hang in there, you know this shit.
Unfilled craters are wonderful places for cracks to initiate. If you don't like them, take a magnifier (encouraged by D1.1) and call it on cracks.
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