American Welding Society Forum
Welding to b31.1. Company welding strut mounted pipe supports using fillet welds. Fillet weld is 1/4 2-6. Which direction should the fillet welds start and end? People arguing over this. What is right and wrong according the to the book. How is it done in D1.1 as well.'
Only spot I can see 'direction' would be an issue is 3G/Vertical. D1.1 is Uphill progression only. Otherwise for all other positions its which ever way works, taking in to account heat distortion.
The little bit of ASME work I have done, as long as you are qualified, Up or Down hill was fine.
- Shop QC/CWI
After reading it, I messed that question up. Where should they start if I were inspecting on flat. Left to right, right to left, or center and out to both sides.
What I like to see...is starting at one end(either end) placing 2" long fillets every 6" and then tying down the end with an additional 2" fillet if the spacing is less than 6" to the free end. This way there are no free ends flapping in the breeze. The 2" fillets every 6 inches are measured from center to center of each individual 2" fillet.
Agreed. Is there a specific spot in the d1.1 or b31.1 that states this information.
look in A2.4
Unless the drawing specifically requires welds at the ends of the joint, the intermittent fillet weld can begin a full unwelded space from either end. In other words, the three criteria the inspector should look at are:
1) The minimum size of the fillet - as specified by the welding symbol. Under run (undersize) is as permitted by the applicable welding code/standard.
2) The minimum length of the weld increment - as specified by the welding symbol. Only the full sized weld should be considered disregarding the "cold start" or unfilled crater.
3) The maximum unwelded space is the pitch minus the increment length.
My comment is based on an interpretation I received shortly after the 1976 edition of AWS A2.4 was released. I notice the note requiring the intermittent fillet weld begin at the end of the joint and terminate at the opposite end with a full length increment. The response from the committee was that the designer has to specify a weld, separate from the intermittent fillet weld symbol, if a weld at the ends of the joint are required. Their position was A2.4 is a standard covering welding symbols, it was not intended to be a workmanship standard. The later was the purpose of D1.1 and other welding codes. It also included a comment with regards to A2.4 implied no tolerances, again, tolerances were the purvey of the welding standard.
With the last comment in mind, the welding symbol does not prohibit welds that are undersized or larger than that specified, nor does it address welds that are too short or longer than that specified by the welding symbol. The welding standard, not A2.4, addresses issues relating to tolerances.
Best regards - Al
Great post Al That's something I didn't know.
We do lots of intermittent fillets on crane rails.. Our shop standards detail specific weld lengths at both ends that are longer than the length of the intermittent fillets. Sound/conservative engineering exceeding code I suppose.
BTW I was in 7th grade in 1976
BTW, I was in 6th grade in 1976
...edit: wait a minute Lawrence, according to your profile, you weren't even born in 1976
Birthday 11-03 (Nov, 2003)
"the designer has to specify a weld, separate from the intermittent fillet weld symbol, if a weld at the ends of the joint are required." - Al
Years ago when I was making shop drawings, I used to add a note in the tail of the intermittent fillet weld symbol to relay my intentions...ie. Fillet weld size x length @ each end
Unless the drawing requires a weld at each end, I've always started in the center and worked my way out towards each end. That way, the series of intermittent welds, which are typically spaced twelve inches apart, are always centered up on the piece to be welded, as opposed to starting at one end and working towards the other end, which can end up with the last weld being ten or eleven inches from the end. When this is the case, the layout man marks a weld at the end, which adds more welding labor, especially when multiple pieces are to be welded. It's just always made more sense to me to start in the middle with a mark, and then mark twelve inches towards each end.
Not a bad practice, but not mandated by a code and for most of today's fitters/welders, that's way too much time trying to figure out the math to make it work.
Too much time, for example, to figure out the center of a 223" piece, which is 111 1/2, and begin marking welds, as opposed to making extra welds, especially on multiple pieces? To me, in my humble opinion, it's a no brainer.
yeah but Scott, have you seen these guys taking their shoes off because they don't have enough fingers? And then, trying to cut them in half to figure out how far half way is? Not a pretty picture.
I know what you mean and used to do most of my own that way also. Just like the difference between how many people guess at picket spacing as opposed to really calculating it out to get even, code compliant, spacing all the way from one end to the other.
Ultimately, our way IS faster though the math at the beginning may take a few extra seconds. But, try and convince today's nickel rubbers of that especially while standing there watching some guy try to do it who can't even read a tape let alone do the math.
I guess you're right Brent. I've always said that there are three kinds of people in this world.... those who can count, and those who can't.
Yep, and you haven't changed a bit...
We decided to avoid partially amputated toes by making up "weld pitch gauges" for our more "challenged" welders. Bar stock with milled out slots where the welds go in various weld lengths and pitches, so they can use the gauge with a silver streak pencil to lay out their welds. Saves time trying to explain what all those little lines and numbers on the tape measure means...
Not disagreeing with your suggestion or methods of layout, just pointing out some lazy ways that I've been around and became accustomed to.
I had a tough time getting the guys to tack where they would be welding these intermittent fillet welds(ie bent plate pour stop)....never fails I come along to look at the finished welds and find fit-up tacks that have to be taken out because they did not place them so that they would be incorporated into the final welds. In my mind and when I was laying out where the bent plate went and marking for the welder....I saw no reason not to tack in those locations, just keep them small enough to melt. But that was too much work for some reason, so they said.
The goal of any contractor is to maximize profits while still meeting the minimum requirements of the code, design, and project specifications. Quality control function is to ensure the same and to remove unacceptable product from the productions stream as soon as practical to eliminate or minimize wasted labor on parts or components that will not or do not meet the quality requirements of the project.
There simply is no justification for wasting time, labor, or materials on aesthetics if the component is buried in concrete or not exposed to view once the structure is completed. In this case, intermittent fillet welds are used to transfer loads from one member to another. Generally, the loads are a minor concern, but stiffness, buckling, or angular distortion is a concern. Whether the weld extends to the end of the joint is usually not a structural consideration (consider the function of a pour stop), if it were, the designer would specify welds of a specific size and length at the ends.
I once worked for a manufacturer that essential was pushed to subcontract much of the fabrication to outside contractors to take their internal QC out of the picture. In-house QC would routinely reject any work that had any undercut, any spatter, any visible spatter. None of the blemishes affected the form, fit, or function of the product. The hours spent removing the blemishes that would never be seen and in no way affected the serviceability of the product drove up the cost to the point where the company was no longer price competitive. There was a disconnect between the function of QC and the realities of the code and the marketplace. The company no longer manufacturers the product in-house, all the fabrication is done by subcontractors that have quality control that is more in touch with the requirements of the code and what factors are materially important. There is no need to produce a gemstone when rough aggregate is all that is needed.
Time laying out to precise dimensions intermittent fillet welds translates into time wasted and profits lost. The only concern to the inspector or the welder should be; are the welds of the proper size (recognizing they may underrun the size specified if permitted by the fabrication standard), are the unwelded spaces between increments equal to or less than the calculated value of pitch minus increment length, and are the increments at least as long as specified by the welding symbol.
I use dividers and a fillet gage to check intermittent fillet welds. I select a fillet gage that meets the minimum size permitted by the symbol and then I set the dividers for the minimum increment length. I check the lengths of the increments, disregarding the unfilled craters or cold starts. Next I check the unwelded space between the full sized welded increments. Checking the layout to verify the center to center distance between the increments is a waste of time and effort. The concern is whether the welds are strong enough to transfer the load from one member to another. The presence of acceptable amounts of undercut, spatter, etc. has absolutely no bearing on whether the component will fulfill its function in the completed structure.
Am I advocating work poor workmanship, shoddy work practices, etc.? No, but I believe one must not expend time and effort on workmanship issues that serve no useful purpose. A well trained QC department in conjunction with a trained design team should recognize when aesthetics are important and when perfection serves no practical purpose. There is a reason the codes include no criteria or definition for “ugly.”
Just my thoughts on the subject.
Best regards - Al
i have the D9.1 offset corner joint again, what would you consider full throat to be if your able to view internally the weldment? and if my construction documents dont refer to melt through or backing im going with i dont need to look for CJP i need to look for fusion and no line segments of un fused metal?
So all fillet weld staggering and spaceing should be by all the code and standards ive read. are center to center measurments ? any one seen it put differently ?
if it isn't dimensioned out differently, yes, the spacing dimensions are center to center.
See A2.4 for confirmation, if someone is saying something different to you.
which book are you refering too? A2.4
Yes, AWS A2.4:2012
Fig 33 A-E shows examples dimensioned from center to center
Paragraph 8.4 Intermittent Fillet welds
The pitch of intermittent fillet welds shall be the distance between the centers of adjacent weld segments on one side of the joint[see Fig 33(A)].
Just to clarify, normally, because it is faster, easier on the brain, and works out the same, you will hear people describe the layout and welding of intermittent fillet welds this way: Start at the left hand edge where you can hook your tape, go the distance specified as the 'run' (in the case of a weld described as 2 - 12 it would be 12") and mark your piece, continuing the whole length of the part. Then, go back, or do it at the same time, and mark your part two inches from each of the other marks not forgetting the start end '0'. So, you have welds starting at each 1' mark (0, 1, 2, 3 feet respectively) and ending 2" down (at 2", 14", 26", 38", etc). The last weld may be closer than the 10" space between welds. Closer is not a problem, only too much space.
Now, as John stated, unless the dimensions are called out differently; this will take place on a detail with very specific dimensions that may vary from what was previously described in that while it is still a 2 on 12 pattern, it may state you need a 9" fillet weld at each end prior to starting the intermittent pattern and/or it may call out a short space that will do as some have thrown out and allow even spacing at each end with the pattern throughout the mid section but the ends are even at each end and shorter than the pattern.
This is especially used when certain members are exposed and it has an 'eye appeal' or cosmetic factor that is desired by the architect.
But, the bottom line is, yes, intermittent fillet welds are laid out center to center. How you get there and how you finish odd lengths is totally a matter of personal preference or engineer requirements.
He Is In Control, Have a Great Day, Brent
got ya... sure do miss the pipeline...lol but really enjoy having to apply myself in this fabrication for nukes world.. man the NQA codes are freaking picky, and the paperwork is overbearing and over wellming....
i appreaciate all the info i get from yall. thanx a million
Man, I hear ya on the paperwork....I don't mind the paperwork if I can see a real life benefit that actually makes a difference in the quality of a product. Some of that stuff has no real purpose or effect on quality of the product, it is just paperwork that has to be completed and filled out to appease some auditor somewhere because he saw it in a book somewhere and thought it was a good idea.
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