American Welding Society Forum
Please see the attached contract drawing and tell me if you think this requires a CJP or a PJP and why?
I have my opinion, and have asked two other CWI's but I'd like a broader opinion.
D1.1 Structural Steel 2" plate. Standard AWS welding symbols apply per AWS 2.4
Based on AWS 2.4 I would say PJP.
Measurement shown at left of symbol (not in brackets) is Depth of Bevel - which in this case is 1/4"
CJP with 1/4" fillet welds added to the CJP weld.
PJP for sure, 1/4" bevel on both sides of a 2" plate, you might end up with 5/6" or even 3/8" penetration, but you still have something like 1.25" of unwelded thickness
I think we are all wrong.
After looking at the joint again I think it is not a CJP or a PJP - it is a PSD (Pretty Stupid Detail)
Take away the 1/4 and you have a Double Bevel CJP with unknown covering fillets.
Put the 1/4 back on and you have one of these (based on AWS 2.4)
1 1/4" Depth of preparation Single Bevel on the Arrow Side with an unknown size covering fillet/Single Bevel CJP with unknown size fillet on Other Side
2 Double Bevel CJP with 1/4" covering fillet on the Arrow Side and unknown fillet size on the Other Side.
Whichever way you look at it it is very poor,
Shane, common sense alone tells you that someone has tried to knock-up a sketch for CJP with back-up fillets. Who ever drew it probably cannot spell AWS 2.4 never mind know the finer points of welding symbols.
It is not drawn properly. I cannot tell if the 1/4 inch is referring to the depth of the bevel on the arrow side or the size of the fillet weld on the arrow side. In either case, the groove weld utilizes a double bevel groove to provide complete joint penetration since no weld size is provided on the other side (assuming the 1/4 inch refers to the depth of the bevel on the arrow side).
Since we have been informed that this is per AWS D1.1 and per A2.4; the depth of the smaller bevel must be at least 1/4 the thickness of the base metal, that would lead me to believe the size of the fillet weld is 1/4 inch and not the depth of the bevel. If I deduced the size of the fillet properly and the fillet weld is 1/4 inch, the depth of the two bevels are equal or 1/2 the thickness of the base metal minus the root face. That still leaves the question of the fillet weld size on the other side. I would default to the prequalified joint details and look for a 3/8 reinforcing fillet weld on the other side based on the footnotes applicable to the prequalified joint details for AWS D1.1.
My guess is that the Engineer is an old codger that hasn't bought a copy of "Mark's Handbook for 'fill in the blank' " since he was first hired out of college. The last time I looked at a new edition of that particular reference the welding symbols were at least twenty years out of date. Never did purchase a copy, I figured if they couldn't get the AWS welding symbols correct, what was the chance they got anything else right?
While this is a fun game, in reality I would defer the question to the Engineer and make him earn his pay. I would neither accept or reject the welds until a written response from the Engineer was in hand.
Typical crappy welding symbol we all encounter on a daily basis. I believe Shane and I are in agreement on this one.
Best regards - Al
First these sketches are not satisfactorily giving enough direction to the welder to make a weld, they appear to be intended to convey the engineer's load requirements to the detailer or other connection engineer who through a knowledge of the shops capabilities and process's can detail the joint conveying the engineers requirements to the welder.
I would either treat it as a CJP or RFI for further direction.
I agree with nantong and Al in the weld required to do this as drawn is a CJP with 1/4" fillet or submit an RFI.
There is no depth or ° of bevel shown here so the 1/4 as shown could only be for one indicator and as all others required to accomplish this weld as a pjp are missing it is for a 1/4" fillet weld.
Once again just my ¢¢'s
It is not the decision for the Inspector to try and interpretate the intent, if it is not clearly defined in accordance with A2.4 then the only option is to RFI with the Design Engineer. To play it safe and weld CJP is not the answer, If you do not know the intent or can not determine from the detail provided the only answer is the ENGINEER.
We can all assume this or that, but we all know what that will do.
First of all....on the left, what the heck is the symbol pointing to?
I have to agree with Richard Cook on this one(send an RFI)....usually when we are against the schedule and there is no time to RFI, I will opt to give the customer more joint than they paid for when I don't understand the welding symbol, but in this case...it leaves way too much to the imagination.
Great discussion and thank you all for your input.
Shane, you and I think alike I agree with what you have said here completly, and ESPECIALLY the fact that you came up with a new acronim (PSD).
We had intrepted it as a PJP with a 1/4" depth of bevel and an undertermined fillet weld size to be installed on top. This was because as we all know the 1/4" is not in (paraenthesis) as required. Additionally what I coulnd't show you becasue the size of the scan would be too big is that other CJP welds on the same sheet say "CJP" in the tail, which helped steer me away from the CJP because they clearly showed when they wanted a CJP on other joints and this didn't say anything.
Either way this is a poor symbol to accuratly relay exactly what is required.
I have RFI'd this and there answer is CJP.
Ironically they have attached a copy of figure 16 from AWS 2.4 and say their symbol matches the figure and and meets AWS 2.4. I am disputing that now as I write this.
Again, thanks for the input
the symbol on the left you are questining is pointing to 3 layers of plates welded together( with the hatched lines) and then there is my weld symbol in question with the 2" plate coming into it to make a T joint. I top view wouls look like a T with the top of the T three plates thick vs only one.
Ah OK Chris...I see that the stem of the "T" is tapered...I missed that when I looked at the sketch, it sorta got lost in the dimension lines.
Follow up to this situation.
We are in negotations now to try to resolve this issue.
Their official answer is that AWS 2.4 requires all PJP weld joint symbols to be in (parenthasis), that since their symbol in not in parenthasis that it is a CJP with a 1/4" fillet over it is the answer.
I feel that is a very sloppy way to relay that information.
Now that I had to dive back into this, I can see their point about the paraenthasis,.. I don't agree with it. I still disagree about the clarity of the symbol, it's as clear as mud and not correct.
A dimention on the reference line before the symbol, not in parenthsis is the Depth of Bevel, which in my case I say is 1/4".
Frustrating to say the least.
A dimension on the reference line before the symbol, not in parenthesis is the "Depth of Bevel; Size or Strength for Certain Welds."
I am not saying the symbol is not lacking, just that there is more to the description than just "Depth of Bevel".
Engineers are notorious for F'ing up weld symbols. I can count on one hand with fingers left over the number of engineers I've met that knew squat about them.
This sketch was drawn by an detailer that isn’t current with AWS welding symbols. I believe that is a safe statement because A2.4 was revised in 1976 and has required each side of the joint, i.e., arrow side and the other side, to be dimensioned separately ever since. Since that was 30 plus years ago, I believe it reasonable to say the detailer/engineer is “old” or at the very least “not current” and possibly “no longer relevant”.
That being said, I would interpret the symbol as specifying a CJP double bevel groove weld with 1/4–inch reinforcing fillets.
Haven’t we seen this recently from you Joe? It looks familiar. Going back to the original thread I do see it is the same question that was asked several months ago. My original response still stands, ask that the symbols be corrected and clarified so there is no question regarding interpretation. The detailer/engineer should be using current welding and NDT symbols per the most recent revision of A2.4, not one that is 30 years out of print.
One last comment, D1.1 has long stated that a weld without dimensions shall develop the full base metal strength in tension and shear. Reference clause 126.96.36.199 (D1.1-2006 as an example). The designer/engineer/fabricator would have detail the actual welds to develop the necessary strength. That is usually the design professional's responsibility. It is not within the welder's or the CWI's job descriptions to to take on those responsibilities.
Best regards – Al
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