6GR Welder Qualification Limitation

By Nanjing Date 02-28-2009 15:24 Edited 02-28-2009 15:30

I am sure in the long dim distant past 6GR welders were qualified to weld 6G. From table 4.10 it is my understanding that AWS have decided that welders who master the technique of pipe butt welding and welders who have mastered the technique in welding tky connections are not interchangeable when the welds are single sided welds or have not even been back-gouged that is the technique of depositing the root pass is significantly different. I don't know why you make reference to LB52U and LB52 electrodes as they are brand names for Japanese 7016 and 7018 electrodes and would not be referenced in the code.

By Nalla

Date 03-01-2009 01:37

Dear ALL
Thanks, Nanjing
Yes, LB52(E7016)/LB52U(E7018) Kobelco Electrodes fall into AWS 5.1 Classification.
Appreciate more responses form Welding Experts.

By Kix

Date 03-02-2009 20:04

6GR is not indicated to be a full penetration joint therefore you can not weld on pipe without a backing ring or backgouging. If you want your guys to be qualified on pipe in all positions, have them do a 6G pipe test with cjp or which ever your WPS supports. I'm assuming since your using 7016 and 7018 that you intend to have your welders do a CJP pipe test. Hope this helped a little bit.

Kix

By kipman

Date 03-02-2009 22:26

Kix,
6GR is a test for the qualification of WPSs or welders from one side without backing for CJP welding. Ref in D1.1:
- 4.12.4.1(1) for WPS
- 4.26(5)
Mankenberg

By Kix

Date 03-03-2009 13:49

The weld symbol on figure 4.27 does not indicate a CJP weld so I'm still sticking with that and why the notes say not qualified for joints welded from one side without backing and from two side without backgouging when you do a 6GR test. 6GR is basically a test for T-K-Y. If you want to be good across the board and T-K-Y, then 6GR and 6G look to be the tests one would need to take. I'd also like to see somone get a full pen weld on a 6GR test when you have 3/16" high low all the way around the inside of the pipe and a 1/8" gap (Not happening). So maybe that's why they have the notes in 4.10 because you can't get full pen, or consistently anyway. Well, that's my answer to the mans question.

By kipman

Date 03-03-2009 15:03

Kix,
Actually, per 4.2.2 of AWS 2.4 the welding symbol shown at Fig 4.27 does indicate a CJP weld. As to why a 6GR qualification does not qualify for tubular butt joints without backing or backgouging, who knows. We would need the opinion of someone who was on the D1 code committee when that was debated. I suspect the reason is that the skills are different - in a tubular open root butt joint you have to break down both edges at the root to get CJP (i.e. avoid IP) while for a TKY you only have to break down the edge on one member.
As such and with due respect, your statement that a welder can't get full penetration on a 6GR test is incorrect. It is important to understand that the 3/16" "hi-lo" of Figure 4.27 is not actually hi-lo in an ASME piping sense. It is meant to simulate a T, K, or Y joint (not a butt joint) and as such the welder does not have to break down the ID edge of the heavier member. This configuration is used so that it is easier to test (RT, tensiles, bends, etc). The 3/16" hi-lo is essentially mimicking what would be the through member on a TKY.
Regards,
Mankenberg

By Kix

Date 03-03-2009 15:36

That's really good info! About the CJP, I ment you would have a hell of a time breaking down both sides with a 3/16" high low with that joint config. I did not know you only had to break down the thinner side for I tried to find something that said that just in case. The weld symbol on my Figure 4.27 AWS D1.1(2006) only shows a single bevel with nothing on the other side of the symbol stating they want a full pen weld (They should have a melt through symbol on the other side). I still believe the reasons I stated are the methods behind the code committee's madness. ;-) You have to show you can break down both sides of a pipe joint to be qaulified for pipe and tubing without a backing strip or backgouging. I don't think they intended to have both sides broke down on the joint config in fig 4.27.

By Nalla

Date 03-05-2009 09:28

Dear All

Ist of all appreciation for all the inputs. I'v conducted the test and got almost perfect RT result which shows excellent root penetration using E7018.
1) Fig 4.27- in my opinion the symbol clearly show FP weld
2) Why it is not recogonised as butt weld joint despite the simulated "hi-low" fitting? which welded without backing?
3) Why in first place need backgouging when the 6GR welder can produce full penetration weld EVEN in 6GR test position?
4) Appreciate if experts from AWS Committe would participate and clarify Note "d"

I hope no one get irritated/agitated with my question.
Thanks for the all the invaluable guidance.

By Kix

Date 03-05-2009 13:24

I guess Fig 4.27 must show full pen in D1.1 2008, but it does not show this in 2006. I'm not sure that we have anyone from the actual D1.1 committee participating in these forums, but you can call AWS and ask to talk to one of their committee guys. I'm sure they will tell you it's because of the High low and it's easier to put a fillet weld on the inside of a pipe with that joint detail then it is to actually put a "real root" in two proper fit-up pieces of pipe with 7018. It's ment to simulate T-K-Y like said above.

By Nanjing Date 03-05-2009 14:39

It is purely to simulate what happens when you weld a t-k-y connection in the field but the test is adapted so it can be done on a pipe-butt weld in order that mechanicals can be taken easily for a procedure qualification and for the welders test the restriction ring simulates the restricted access for welding such a single bevel joint and from the root perspective the requirement to fuse the incoming bevelled member to the through member and achieving the required fusion and penetration.

By kipman

Date 03-05-2009 15:34

Exactly. And it does not simulate an open-root butt joint because the 6GR test does not require the welder to fuse together at the root two beveled members.
Mankenberg

By Kix

Date 03-05-2009 16:50 Edited 03-05-2009 16:55

And there ya have it folks. Hope this answers the thread posters question, but he can still call AWS and here it from an expert if he wants. Hey Kipman, do you have a copy of the 2008 edition? Does the 2008 edition show a drop through symbol in figure 4.27 on the other side of the reference line from the single bevel? I still don't get where you guys are coming up with the weld symbol showing full pen on the back side of the joint. If you have a 2006 edition, see if they are the same symbol because mine does not show a full pen weld.

Kix

By Kix

Date 03-05-2009 17:03

Here's a pic of what I have in the 2006 edition that does not show CJP, but as you know this joint setup is not really one to spec that out. http://i11.photobucket.com/albums/a189/vdubin474/MVC-007S.jpg

Here is a pic of what it would look like if they wanted CJP. http://i11.photobucket.com/albums/a189/vdubin474/MVC-008S.jpg

By kipman

Date 03-05-2009 22:52

Kix,
Both 2006 and 2008 are the same. It is a CJP symbol due to this blurb from 4.2.2 of A2.4: "Complete Joint Penetration. Omitting the depth of bevel and groove weld size dimensions from the welding symbol requires complete joint penetration only for single-groove welds and double-groove welds having symmetrical joint geometry". Various figures are also referenced that illustrate the concept - the best one in this instance is Figure 22 (D). It also references B4.2.2 of the Commentary. This is probably the most helpful, because there it states "complete joint penetration is defined as, "Penetration of weld metal through the thickness of a joint with a groove weld". The simplest way of specifying such a groove weld is to show no dimensions to the left of the groove weld symbol. This is the intent of 4.2.2."

Since the symbol in 4.27 shows a single bevel groove weld without dimensions, it is therefore CJP.
Mankenberg

By Nanjing Date 03-06-2009 08:42

Agree with you 100%.

By Kix

Date 03-06-2009 13:15

Kipman,

Thanks for clearing that up! I was wondering what you were refering to when you kept referencing 4.2.2. I checked it out and it was about aging and I was like, huh. All I have to go by is D1.1, I don't have anything else to look at. I remember someone else talking about weld symbols that had no detail to them in another thread. I think they stated the same thing about if they don't show any detail to assume they are CJP now that you bring it up. Thanks again.

Kix

By Nalla

Date 03-07-2009 04:12

Hi Kix
Can you pls explain your statement further?
"You have to show you can break down both sides of a pipe joint to be qaulified for pipe and tubing without a backing strip or backgouging. I don't think they intended to have both sides broke down on the joint config in fig 4.27."

Btw can non-member post question to AWS Committe?

Thanks

By Kix

Date 03-07-2009 18:05

Yes, but I still don't know about posting a question to the committee. Just call AWS and tell them you have a code question and they will put someone on the committee on the phone with you.

By Shane Feder (****)

Date 04-06-2009 10:24

Hello Kip, Nanjing and Kix,
I agree with what everyone is saying about CJP but while doing a bit of research on this subject I have become even more confused and hopefully someone can clarify.
I only have the 2004 edition of D1.1 so maybe some of my queries have already been answered.

4.5 Weld Types for WPS Qualification "PJP Groove welds for T-Y and K connections and butt joints ..."
There is no mention of CJP Groove welds for T-K and Y connections in this section ?

4.20 Weld Types for Welder and Welding Operator Performance Qualification (5) " PJP Groove Welds for Tubular Connections (see Fig 4.27)

I personally agree with you that Fig 27 is supposed to be a CJP Groove Weld but what do you make of the two notes above ?
Regards,
Shane

By Bert70

Date 04-07-2009 10:56

Shane,
(using D1.1-2002 to reply from home)

Regarding 4.5 - Item (4), refers one to 4.12 for CJP groove welds in tubular connections. Then items 4.12.3 thru 4.12.4.4 discuss T-, Y-, K-Connections.

Regarding 4.20 - Item (4) refers one to 4.26 for CJP welds in tubular connections. Then items (4) thru (6) discuss T-, Y-, K-Connections.

Hope that points you in the right direction.

-Bert

By Shane Feder (****)

Date 04-07-2009 12:18

Thanks Bert, much appreciated.
I was getting confused between 4.26/4.27 and Fig 4.26/4.27
Cheers,
Shane

By Duke

Date 05-05-2009 12:20

Whenever a contractor tells me "that's a partial" for a non-dimensioned groove weld symbol, I ask, "how much of a partial" and that discussion is over.