I have several confusion with D1.1, please help me ,thanks in advance,
1, Is weld access holes/beam copes on web mandatory for a CJP joint? or as long as the welder can meet the penetration requirement,the fabricator can do the welding without the weld access hole?
2, Can i use a CJP WPS(use the same process,parameter...) to weld a PJP weld or filler weld without made a new WPS for PJP welds or filler welds ?
3, For the welder qualification test with RT (backing removed),is it allowed to weld the second side after the removal of the backing(due to the damage during the remove of the backing)?
1, Is weld access holes/beam copes on web mandatory for a CJP joint? or as long as the welder can meet the penetration requirement,the fabricator can do the welding without the weld access hole?
I guess you are reffering to scallop, this hole is to provide easy access for welding of splice joint on flanges. Without a hole, 100% NDT may not be applicable on splice joint. If this hole is provided in the drawing, then you follow accordingly.
2, Can i use a CJP WPS(use the same process,parameter...) to weld a PJP weld or filler weld without made a new WPS for PJP welds or filler welds ?
You have to undertstand the essential variable in table 4.5 to 4.7, whichever applicable.
3, For the welder qualification test with RT (backing removed),is it allowed to weld the second side after the removal of the backing(due to the damage during the remove of the backing)?
You don't remove the backing bar during qualification test.
~Joey~
Thanks,Joey
I still confused,
1, If the holes were on the drawing,that's no problesm, but I was wondering if this weld(splice joint on flanges) was CJP,and NO NDT was required,also no hole provided on the drawings, so can i ask the contractor to cut a hole?
2, I understand that any change of the essential variable in table 4.5 to 4.7,requalification was need, but as per table 4.1, a groove CJP test qualify PJP and fillet joint, so my question is without any change of the essential variables, can i use a CJP WPS to weld a PJP weld or filler weld, without write a new wps for PJP welds or filler welds base the PQR, where the CJP WPS come from
3, Refer to footnote b of figue 4.30,4.31 ,4.32(D1.1 ,2010) "b ...... backing width shall be 3 in [75 mm] min. when not removed for RT, otherwise 1 in [25 mm] min. " In my understanding,this means i can use the 25mm width min backing bar, and remove it before RT ,am i right? my confusion was can i have a little welding repair on the second side before RT?,
1. If you are fabricating a build-up beam, there might be no hole requirement at the web because the intention is to weld the slice joint on flange prior to fit assembly of web plate.
You should ask the Engineer in-charge whether they will allow you to cut a hole, you cannot just simply cut a hole without written details from engineer or designer.
2. A separate WPS should be made for fillet weld or PJP although exempted for WPS qualification as per Table 4.1 using CJP qualification test.
3. Repairing the gouge marks on tack welded areas of backing bar? I don’t see any problem if this little welding repair will not interfere the area of interest for radiopraphic testing. The weldment (root pass) produced during performance test should not be repaired by grinding & welding.
~Joey~
Gee wizz Joey, what is a scallop? Maybe it is the same thing as the snip or maybe it is the rat hole. Which is it Joey?
Is it related to the hickory nuts on the log?
Al
Hi Al,
This is another of the non-standard (AWS) terms we disagreed about previously.
The term scallop (or as per AWS - the cope hole) is widely used in the Asia - Pacific region .
The link below is actually from a Canadian, not sure whether it is standard terminology for them.
http://www.iitk.ac.in/nicee/wcee/article/13_1235.pdfRegards,
Shane
Is "Tuck welding" and "bucking bar" standard terminology for them too?
That was a serious question. I seen it spelled that way several times in the article you posted.
By your "be nice" statement, I will assume it was spell check gone awry.
ctacker
i'm from asia, don’t pretend that you don’t know the answer to your question, are you some kind of insensitive fellow...feeling superior to others.
let see if you are technically capable, can you say something technical to help this confusion?
bert
great article to read! thanks shane
ctacker,
I never even read the article - I just used it as an example.
My comment about "being nice" was based on the fact that a lot of people criticise New Zealanders (and I am a proud Kiwi) of how we speak and they use words exactly like you quoted - I thought you were taking a shot at me.
I will still stand here and take a shot at Al who I consider to be one of the most knowledgable and influential members on this forum but to repeatedly query other members use of "non AWS terminology" in their posts is being a bit pedantic.
I can understand " hickory nuts on a log" is a joke but the "non AWS" terms we have disagreed on are terms that are used every day around the world.
DNV (European) have a standard for Fatigue stresses in off shore structures that reference "scallops" repeatedly - so "scallops" terminology seem to be accepted everywhere in the world but the US.
We have a huge amount of posters from all over the world, do you want to lose potential members because they post a question and use a word that is used regularly in their home country / region only to be shot down because it is "non AWs terminology" ?
Regards,
Shane
Not taking any shots at anyone.
I have never heard the term scallops either, and after looking at the article and seeing the spelling of backing bar as buckng bar several times, I was not sure if that was also something that was used elsewhere in the world.
insensitive or not, to me it was a legitimate question.
I'm here to learn also, not to squabble over terminology.
Regards,
Carl
Hey Al- A Scallop is a highly mobile Bi-Valve. From it, humans use the Eductor Muscle, and such as they call it a "Scallop" like you might order down at the "Catch of the Day" restaurant.
Put up your dukes Shane!
I get your point, but in consideration that the questions posted are relative to an American Standard, i.e., AWS D1.1 it would seem to be logical to use terminology that is consistent with the standard in question.
The question was technical in nature, it was not casual conversation. As a technical question, technically correct terminology would be in order to mitigate the chance of miscommunication. If I was making an inquiry about a foreign standard I would use their terminology unless I was asking a question in regards to what a term meant.
For instance, if I read a standard that used the word "scallop" and I didn't know what it was, I would hope someone would say that it was the same as "access hole" as used by AWS D1.1.
I could have used the words snipe or rat hole which is common vernacular here in the states, but it may only confuse a reader that may be trying to look the words up in a technical document. Confusion reigns when proper terminology is not used especially when trying to communicate with people from other countries.
I don’t believe it is a case of being superior to anyone else; it is a simple matter of trying to communicate clearly.
Back to the writer’s original inquiry regarding the need for access holes:
Access holes through the web of a built-up member or a rolled member is to provide sufficient access for the welder to deposit sound weld across the width of the flange. Weld such as that described can be found in moment connections between a column flange and the top and bottom flanges of a beam or girder.
In the case of welding a bottom beam flange to the column flange, the welding is done from the top side in most cases. The welder has to extend the welding electrode through the access hole and progress to the outer free edge of the flange. The backing bar, if used, is typically placed under the groove to support the root bead while it is being deposited.
An alternate to welding the lower beam flange from the top side is to weld it from the bottom side. This is not usually done because of the difficulty in depositing weld in the overhead position. However, there are situations where overhead welding cannot be avoided. In this case the backing bar, if used, is placed on the top side of the lower flange and the backing bar passes through the access hole to provide continuous backing for the full width of the flange.
The attached sketch depicts the two cases I have mentioned in my response. Shown in the sketches are the lower beam flange welded to the column flange. The web connection shown is bolted.
In the event the detailer decides the entire connection should be welded, i.e., the top and bottom flanges welded to the column flange, as well as the web to the column flange, the access hole would still be used to interrupt the weld joining the web to column and the web to beam flanges because it is not a good idea to have welds intersecting at 90 degrees or other angles. The residual stresses resulting from the welding operation are added as vectors. The resultant can easily exceed the ultimate tensile strength of the filler metal, base metal, or both. The concern with residual stresses becomes a greater issue if higher strength steels are involved and when there are more than two intersecting welds. As an example; consider the beam as a built up member where the web is welded to both the upper and lower flanges. Then consider the welding of the lower flange to the column flange. Then consider the beam web welded continuously to the column flange without the use of the access hole. The connection would have three intersecting welds, each perpendicular to the other. Disregarding ductility, because in a practical sense the joint is highly restrained, the resultant force developed because of the three welds will most certainly exceed the UTS of the base metal and the weld if matching filler metal is used. Increasing the strength of the filler metal makes the problem worse. If anything, under matching the strength of the filler metal (relative to the strength of the base metal) would offer some hope of preventing a crack from forming.
Consider ASTM A36 welded with E70XX filler metal: An approximation of the resultant from the residual forces parallel to the axis of the weld would be on the order of 51 ksi with two intersecting welds.
The resultant force would be on the order of 62 ksi for three intersecting welds, which exceeds the min. UTS or 58 ksi.
If ASTM A992 is used the resultant for two intersecting welds would be 71 ksi and three intersecting welds would be 87 ksi. Both cases exceed the UTS of the base metal (65 ksi min.)
So, as you can see, the assess hole serves several useful purposes.
Shane, that looks like an intersting article. I'll give it a read when I get back home. Thanks for providing a link.
Topic American Welding Society Services / Technical Standards & Publications / Several Confusion with D1.1
