(Reposting previous for more response. Looking for any thoughts.)
I have comiserated for some time the most proper interpretation of
AWS D1.1 , Table 4.9, used in conjunction with Table 4.10., as follows:
If a welder qualifies with a plate groove, Table 4.9 indicates qualification is included for pipe fillets, (as long as dihedral angle is not less than 30d).
Nowhere does it address diameter restriction/allowance. Note 3 (24" restriction) applies to groove welds only, and not fillets.
Can anyone help clarify whether the code simply does not specifically address fillet weld DIAMETER, and the welder is qualified for all diameter fillet welds by performing a plate groove test, or am I missing something ? ASME IX is pretty clear on this matter (QW-452.6)
Elsewhere in Table 4.10, (production T-Y-K connnection fillet welds) there is a provision to test a fillet weld of dia. "D" to qualify fillet welding "D" and greater. But of course this qualifies fillet welds only.
note:
I did (twice) request a formal interpretation from AWS, but have had no response.
Do not ask me where this is written in the book because I do not know. I was told this by AISC. If a welder is ceritified to weld in horizontal position on plate, the welder can weld pipe as long as the welder welds in the positions he/she is qualified in only. In easy to understand words: If the pipe is rolled so the welder is only welding in the horizontal position then plate certification in the horizontal position (or any other position that qualifies the welder for horizontal position) is all he/she needs to weld the pipe.
Jerry
It may be over simplified, code experts chime in here. My understanding is this:
As the size of pipe (in pipe fillets) increases, the difficulty of producing a weld is pretty much unchanged. Maybe it gets a little easier.
To further address pipe fillets would be to stipulate limitations on the *length* of a fillet weld (tee joint) in performance qualifications and welding procedures.
The guidelines on thickness and position remain constant correct? And you have rightly noted the limits on angles. So its very little difference in a pipe/plate fillet and two plates in a Tee joint, and we don't as far as I know, place limitations on how long two pieces of plate can be as it applies to welder performance qualification or welding procedures.
My understanding is the same as Lawrence explained:
"As the size of pipe (in pipe fillets) increases, the difficulty of producing a weld is pretty much unchanged. Maybe it gets a little easier".
Basically, as the pipe diameter decreases, the degree of welding difficulty increases.
I don't see where the pipe diameter is an essential variable for production fillet welds if the welder qualifies using a groove weld.
Good luck - Al
Let me restate that the test given is on PLATE. The fillet weld qualification is regarding (minimum) PIPE fillet welds qualified by testing with plate.
I agree with you on this Jerry, I don't thin diameter was addressed, thicknesses and angles were, but not diameters.
John Wright
Welder A takes weld test on 1" plate in the 2G position.If he/she passes he/she is qualified to weld Flat and Horizontal groove and fillet welds on plate, pipe and tube. You want to know what is the minimum diameter pipe he can weld fillets on while the pipe is rotated (Correct).
In my opinion the minimum diameter pipe the welder is allowed to weld while the pipe is rotated is 4". I say 4" because Table 4.2 says tells me so. If a welder takes a test on 8" or 6" pipe he/she is qualified to weld pipe lager than 8" or 6" but 4" is the smallest diameter he/she is qualified to weld. If the welder takes a test on 2" or 3" pipe he/she in qualified to weld pipe 3/4" to 4".
In my opinion 4" pipe is the point where AWS figures you can not be welding in the flat position because theoretically to them there is not flat spot on pipe that size.
But then agian if a welder takes a test on 4" pipe rotated, he/she is qualified to weld in the flat position. That tells me AWS thinks the flat welding of 4" is not the same as flat welding 6" pipe.
All that being said the welder qualified to weld plate is not qualified to weld pipe that is rotated and 4" or smaller.
Does anyone agree with me or do we all agree to disagree?
I did a little research and I found a link that stated the following:
"Diameter limits for all circular welds including groove welds, branch welds and fillet welds is given in QW452.3".
I don't know what QW452.3 is, but as far as I know, I'm 99.93628% sure that this doesn't apply to D1.1 because of the reasons that have been posted. I'm not sure, but in looking through the website, it looks like the statement may be ASME related. I just thought it was interesting.
Here's the link, just scroll to Diameter and Thickness Ranges:
http://www.gowelding.com/wp/asme3.htm
Table 4.2 is for WPS qualification... Tables 4.9,4.10 and 4.11 address the welder. Table 4.11 General Note(s) points you back to Table 4.10 for ranges of diameters and thicknesses qualified. (in which dia. are not addressed if taking a plate test.)
John Wright
I knew I should have had my morning coffee before I tried to think.
It looks like we are confusing AWS D1.1 with ASME.
ASME Section IX prefixes all their paragraphs with "QW".
Best regards - Al
What do you think about the minimum restriction in relation to the wall thickness? The minimum thickness for the 1" plate test is a 1/8" so I might be lead to believe that as long as the pipe you are welding on is in the flat or horizontal position and the wall thickness is larger than a 1/8" you would be in conformance.
What think guys?
http://www.aws.org/cgi-bin/mwf/topic_show.pl?id=8365#39923
John Wright
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