Walter (CWI)

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This is directed to any CWI's, technical advisors, or anyone that may have a solid comment:At my place of employment, we have several CWI's here that are divided on the Visual InspectionAcceptanceCriteria(AWS D1.1/D1.1M:2008 -- Table 6.1) concerning section (3) Crater CrossSection and the correlation with section (6) Undersized Welds.Question: Does the Crater Cross Section requirement allowus any other exceptions to this rule?Case/question in point: If we have a 5" long weld and the crater is0.5" (10% of the weld length) and the 4.5" length of the weld is to sizebut the crater is undersized and within the limits of undersizedness, isthis weld rejectable because section (3) is not satisfied?In one camp, we have the thought that craters are a separate entity andthat they have their own unique requirements, and therefore are separateand exempt from the Undersized Weld requirements. Their thought is: "Letthe weld be undersized (10% length) anywhere else, but not at thecrater".In the other camp, we have the thought that since the crater is part oftheoverall length of the weld, it is subject to the 'undersized' tolerancesand that the weld is acceptable if the undersized crater length fallswithin the 10% weld length range.Any thoughts and comments are appreciated.Last edited by maslymbaan; 06-22-2010 at 10:01 PM.Reason: Realized that I had posted 'copyrighted' material -- deleted it
Reply:Originally Posted by maslymbaanThis is directed to any CWI's, technical advisors, or anyone that may have a solid comment:At my place of employment, we have several CWI's here that are divided on the Visual InspectionAcceptanceCriteria(AWS D1.1/D1.1M:2008 -- Table 6.1) concerning section (3) Crater CrossSection and the correlation with section (6) Undersized Welds.Question: Does the Crater Cross Section requirement allowus any other exceptions to this rule?Case/question in point: If we have a 5" long weld and the crater is0.5" (10% of the weld length) and the 4.5" length of the weld is to sizebut the crater is undersized and within the limits of undersizedness, isthis weld rejectable because section (3) is not satisfied?In one camp, we have the thought that craters are a separate entity andthat they have their own unique requirements, and therefore are separateand exempt from the Undersized Weld requirements. Their thought is: "Letthe weld be undersized (10% length) anywhere else, but not at thecrater".In the other camp, we have the thought that since the crater is part oftheoverall length of the weld, it is subject to the 'undersized' tolerancesand that the weld is acceptable if the undersized crater length fallswithin the 10% weld length range.Any thoughts and comments are appreciated.
Reply:Why wouldn't the craters be filled to at least the same size as the rest of the weld? This seems a no brainer to me.
Reply:Originally Posted by fortyonethirtyWhy wouldn't the craters be filled to at least the same size as the rest of the weld? This seems a no brainer to me.
Reply:"In one camp, we have the thought that craters are a separate entity andthat they have their own unique requirements, and therefore are separateand exempt from the Undersized Weld requirements. Their thought is: "Letthe weld be undersized (10% length) anywhere else, but not at thecrater".I believe this is the correct point of view. AWS D1.1 2008 Table 6.1(3): "All Craters shall be filled to provide the specified weld size."Now if after filling the crater the weld is undersized then the 10% rule applies.jrw159
Reply:Originally Posted by jrw159"In one camp, we have the thought that craters are a separate entity andthat they have their own unique requirements, and therefore are separateand exempt from the Undersized Weld requirements. Their thought is: "Letthe weld be undersized (10% length) anywhere else, but not at thecrater".I believe this is the correct point of view. AWS D1.1 2008 Table 6.1(3): "All Craters shall be filled to provide the specified weld size."Now if after filling the crater the weld is undersized then the 10% rule applies.jrw159
Reply:Thanks all for your comments:***Fortyonethirty -- we have over 400 welders and multiple robots. We have only recently begun to strengthen our quality standards, hence, the 'transition period' involved in improving our welding quality (personnel and machine).***bleheny, jrw159 and Supe -- I agree with you all. I am of the camp that believes that there is a clear distinction between welds and craters. In the size of the corporation that I am with, production personnel are 'concerned' with the cost increases involved in re-programming robots and literally re-training operators. This may not not seem like a very large issue, but when we are talking 6-digit+ craters on a daily basis and a strengthening of our existent quality improvement program, we are talking 'cost'. My next step is to take this to AWS. Without mentioning corporate names, we've already experienced division on this issue between top training institutes (CWI preparation).Thank you very much for your inputs. When we find closure on this, I would like to post here.
Reply:Maslymbaan,"we've already experienced division on this issue between top training institutes (CWI preparation)."Without a doubt, Hobart Institute of Welding Technology. jrw159
Reply:I feel older than friggin' dirt here! D1.1-94 is my latest reference!"In one camp, we have the thought that craters are a separate entity andthat they have their own unique requirements, and therefore are separateand exempt from the Undersized Weld requirements. Their thought is: "Letthe weld be undersized (10% length) anywhere else, but not at thecrater".I believe this is the correct point of view.AWS D1.1 2008 Table 6.1(3): "All Craters shall be filled to provide the specified weld size."Now if after filling the crater the weld is undersized then the 10% rule applies.jrw159
Reply:I agree with everyone above.  When in doubt use common sense Fill to the full cross sectional etc.etc......Of course now D1.1 2010 is out so....2011 Dodge 3500 diesel duallyLincoln SA-200Lincoln SAE-300LN-25'sLincoln Idealarc R3RMiller Trailblazer 302
Reply:Originally Posted by maslymbaanThis is directed to any CWI's, technical advisors, or anyone that may have a solid comment:In one camp, we have the thought that craters are a separate entity andthat they have their own unique requirements, and therefore are separateand exempt from the Undersized Weld requirements. Their thought is: "Letthe weld be undersized (10% length) anywhere else, but not at thecrater".
Reply:I think the term "specified weld size" requires the crater to be filled to "the specified weld size" and NOT the tolerance allowed by the code.Gerald Austin
Reply:Again, I appreciate everyone's input. It appears, thus far, that everyone that has volunteered input is of the same camp. If we can continue this, I would like to add a response that I received from an individual (in a separate e-mail -- copied/pasted) that is considered to be in 'top form' in the world of welding. He has credentials and a knowledge of welding that some would say, is 'unsurpassed', and if his name were mentioned, most would recognize it. Due to his unique position, I am not at liberty to divulge his name -- therefore, I have deleted any references that would identify him. I included his own caveat/disclaimer that states that this is his OPINION, and his opinion only. Reading this ups the stakes, so to speak, and forces each one of us (above) to look at his reasoning and make any adjustments to our own thinking, if needed. I immensely appreciate everyone's responses, thus far, and hope to hear back from you concerning this 'NEW' take. This is rather interesting, at this point, because we appear to be treading in 'uncharted' territory -- at least as far as an area that appears to need revision/modification from AWS concerning clarification. Please read ahead, as everything from this point on down is his response. Thank you.      "Whatever I say to you in my personal opinion only, not that of the AWS or the D1 committee. Secondly, for the question you raised, I don't ever recall this being discussed in committee. So, all of this is my conjecture, based on my experience, education and some logic. As to (3), the primary intent of the provision is to fill the crater. Underfilled craters won't have the required throat dimension (if the leg remains the same), and moreover, underfilled craters with concave surfaces will often experience crater cracking. As to (7), this provision has been tweaked in recent years. At one time, it was 1/16" less than specified for 10% of the length. This was disproportional: 1/16" off of a 3/16" fillet caused more of a reduction in strength (from a percentage basis) than did 1/16" off of a 1" fillet. Now, three limits are provided, giving a more logical/rational relationship. Some committee members, however, think these limits are wrong since 1/16" is a standard weld size increment. for welds equal to or greater than 5/16", two standard weld size reductions are permitted. Too much, say those who opposed this change, since this is at least in part a workmanship issue (as opposed to a strength issue). Some of the justification for the slight under-run allowed by (6) is simply this: the "cure" (dabbing on some more weld metal to make up for a slightly undersized weld) might be worse than the "disease". I've provided all this background to give the context of Table 6.1, which is in my opinion a blending of both reasonable workmanship criteria, as well as engineering criteria. Whether the undersized weld shows up in the crater, or in the body of the weld, shouldn't make any difference, unless there is some unique loading condition associated with the end of the weld with the crater. This concept is partially reflected in the final sentence of Table 6.1(6). Given all of that, my thinking is that the crater should be permitted to be undersized, within the limits of (6), so long as the crater is filled flush. And, remember my initial caveats."