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Up Topic Welding Industry / ASME Codes / Backer, no Backer, essential variable?
- - By PFI (**) Date 06-15-2015 00:17
I'm 95% positive about this but I want to be 100%, I was reviewing a WQTR and noticed it was rev'ed to rev 4.  The rev. was to remove the backer from the vee beveled groove test.  The supporting PQR and WPS are both at the original revision and the backer is NOT removed.  As I understand it, this is an essential variable and would require a new PQR and WPS.
Parent - - By jon20013 (*****) Date 06-15-2015 01:47 Edited 06-16-2015 21:51
Fred, maybe just old age here but I read your post 3 times and it sounds to me like there may be some confusion between construction and WPS qualification?

To me, it sounds like whomever made the revision wants the backer removed AFTER welding... the essential variable for ASME is if a WPS is qualified WITHOUT backing then backing may be used in production BUT if the WPS was qualified WITH BACKING then production welds cannot be made without backing....

It's often undesirable to leave backing in place after welding so not sure why the revision was made to the WPS???  If it were intended to weld WITHOUT backing then requalification would be needed HOWEVER if it were intended to removed backing AFTER welding then nothing would be required except perhaps a clarification of the revisions intent.

Sorry if I'm the only one confused by reading your post...

EDIT: My error, even I was thinking welder and speaking WPS... easy to do for old timers, lol... BACKING in NOT an essential variable for most processes in ASME IX WPS qualification.
Parent - By js55 (*****) Date 06-15-2015 13:54
I think we need a clarification. For WPS's backing is a non essential variable except for processes such as electron beam or laser beam welding.
For performance qualification it is an essential variable but its a one way variable. If you weld without backing you can then weld with.
Parent - By PFI (**) Date 06-16-2015 01:26
Jon,

Wow, I'm confused by reading my post!! sometimes I just can't help myself and continue to work even though I'm tired and it shows in that post!

I was reviewing a welder qualification and noticed it was rev'd to level 4 while the PQR and WPS were both at level 3, that got me to look a little more into why it was rev'd.  I noticed that the person who rev'd it changed the "qualified range" to without backer,  now both the WPS and PQR are both tested WITH backer so I know that all welder qualifications to this WPS must be WITH backer.

I reviewed the process in which this WPS was created and they use to use a ceramic backer and some years after discovered they could weld the joint successfully without the backer si they changed the process.

So by reading your reply, we are on the same page.
- - By 803056 (*****) Date 06-16-2015 03:10
It is easy to confuse the WPS, PQR, and WPQ requirements.

If ASME is the governing standard, the essential variables listed for the welding process in Article II must be addressed and recorded on the PQR.  The WPS must address all the essential and nonessential variables listed in Article II. If notch toughness is invoked by the applicable construction code, the supplementary variables must be addressed and recorded (as essential variables) on both the PQR and WPS.

The essential variables for welder performance testing are addressed in ASME Section IX, Article III. The essential variables are not the same as those listed in Article II.

The welder can be qualified in accordance with a WPS that isn't necessarily the same as that used in production welds as long as the ranges qualified (performance qualification) are adequate to cover the needs of production.

Example: The welder can be qualified using a WPS written specifically for performance testing. The WPS can be very specific with regards to the filler metal classification and diameter, permitted current range, and just one groove detail. The groove detail could be 3/8 inch thick plate meeting SA36 requirements with a backing, 45 degree groove angle, no root face, etc. that specific WPS could be supported by the same PQR that supports the WPS used for production.

The WPS used for production could be qualified for base metal thicknesses greater than 3/8 inch, it could be for all P1 base metals, and the production WPS could include single grooves with backing or without backing, it could include double groove welds that includes a back gouge operation, it could include fillet welds, and it could be used to weld structural shapes as well as piping.

The welder that passed the performance test described would not necessarily be qualified to weld everything the production WPS covers.

Fun stuff, but one must be well versed with the ins and outs of ASME codes.

Best regards - Al
Parent - - By PFI (**) Date 06-16-2015 14:55 Edited 06-16-2015 15:58
Exactally!  The actual process being used by the qualified welders was WITHOUT backer bar, the WPS and PQR were both performed WITH backer, the process being performed was not allowed.  The welder's WPQ was without merit, he could not be qualified to a the WPS (and supported PQR) because both of those were qualified WITH backer bar.

IF they qualified the PQR and WPS WITHOUT backer then they could qualify welders WITHOUT backer and they would have qualification to process the joint with and without backer.

Thank you very much for your input Al :grin:
Parent - - By js55 (*****) Date 06-16-2015 20:21
PFI,
If I understand correctly what you are saying you are incorrect.
keep in mind you do not qualify 'TO' a WPS, you qualify 'using' a WPS.
Parent - - By jon20013 (*****) Date 06-16-2015 21:49 Edited 06-18-2015 08:22
Backing is not an essential variable for the WPS, but it is for the welder; so welders qualified without backing can weld with backing but not vice versa.  Per ASME IX if a WPS was qualified in the flat position (example only) WITH backing it is qualified in ALL POSITIONS, WITH OR WITHOUT BACKING (unless impacts are required and then position would apply).... so as mentioned by others it can be confusing at times.
Parent - By PFI (**) Date 06-17-2015 15:43
Jon,

I must be confusing everyone, I'm not asking about an essential variable on the WPS or PQR, both the PQR and WPS were both preformed using backing.  what your saying supports my original thoughts, the welder performing the joint without a backing is NOT following the WPS.

:lol:
Parent - - By 803056 (*****) Date 06-17-2015 03:06
Fred, I think you are misconstruing what I was attempting to say.

The WPS can be qualified with or without backing. That is the test assembly welded and recorded on the PQR can be welded in any position, with or without backing, for thicknesses in excess of the welder qualification, and it would still be a valid WPS. The reason is that the qualification of a WPS is "governed" by Article II.

Welders are qualified in accordance with Section IX, Article III. The essential variables for welder performance qualification are "very" different from the essential variables that apply to WPS qualification.

Best regards - Al
Parent - - By PFI (**) Date 06-17-2015 15:36
maybe I can make this simple, I have a PQR and WPS both performed using a backer plate, (Both clearly state "with backer only" under the qualification range) the process is being performed without a backer, It seems very simple to me that the welder is not welding within the qualifications.  Keep in mind, the welders qualification record for this process was revised and the "with backer only" was crossed out and "without backer" was penciled in.
Parent - - By js55 (*****) Date 06-17-2015 16:15
Fred,
I think the problem is terminological.
You don't weld within qualifications. You weld using a WPS. In ASME it doesn't matter if the PQR is qualified with or without.
However, it production is does matter what the WPS says.
If the welder is welding without backing and the WPS says with backing simply write a nonconformance and revise the procedure to allow welding without backing.
Parent - - By PFI (**) Date 06-17-2015 18:01
Ok, that makes sense!  The PQR can say either "with backer" or without "backer" it matters not as it's NOT an essential variable in the PQR, just change the WPS to "with backer".  The welder would need to qualify to the new WPS.

Please forgive me, I have been in ASME 9 very little over the past years, almost always in AWS.
Parent - - By js55 (*****) Date 06-17-2015 20:07
The welder doesn't need to qualify to the new procedure. The welder only needs to qualify to a change in performance essential variables.
Parent - - By PFI (**) Date 06-18-2015 02:20
QW-351 General
A welder shall be requalified whenever a change is
made in one or more of the essential variables listed for
each welding process.

Per Qw-355 Backing is listed as an Essential variable and it refers to QW-402 ...

QW-402.2 The addition or deletion of a backing

Given the above information, the welder would need to be requalified, am I missing something?
Parent - - By ctacker (****) Date 06-18-2015 04:11
It does not matter if the procedure had backing or not, the deletion of backing is a nonessential variable and changes may be made to the nonessential variables to suit production requirements without re-qualification, see QW-200.1(c). (all I have to work with is 2007 edition)
If your welder qualified without backing using a WPS that shows backing, all you need to do is revise your WPS to show "no backing". If your welder qualified using backing, and production is not using backing, he would need to qualify without backing, UNLESS production joints are welded from both sides.

My edition of IX shows QW-355 to be GMAW & FCAW, and only shows QW-402.4,  the deletion of (-) backing as an essential variable for welder qualifications.

Seems this is getting more complicated than it should be.

Carl
Parent - - By PFI (**) Date 06-18-2015 10:22
Carl,

I'm sorry if my questioning seems to be hitting on a nerve with you, I'm not some kid out of school, I have been in the industry of welding for over 30 years and weld inspection for the last 10, I'm simply questioning what does not make sense. I understand that the backing bar for the PQR and WPS is a non essential variable.  I'm talking about the welder qualification, as a welder I know it's much easier to qualify WITH a backer then WITHOUT, thus it makes sense that if you qualify without a backing bar your qualification would state "qualified with or without backing bar" BUT if you qualify WITH a backing bar it make sense that your qualification would state "qualified with backing bar only" because if you can arbitrarily change your qualification from one to the other on a whim then backing bar would not be stated at all in the code as it would not matter.

PLEASE understand that the welder qualified "WITH" backing.
Parent - - By Lawrence (*****) Date 06-18-2015 11:20 Edited 06-18-2015 18:42
I "think" what Carl tried to communicate is that performance qualification is required (because of essential variable change) if the CJP weld is made from one side.

If the weld is made from both sides it is of course less difficult and a non-essential variable as explained.

I skimmed the entire thread and did not see you make this part clear.

Is your CJP  production work welded from one side or from both sides ?
Parent - - By ctacker (****) Date 06-18-2015 18:14
Thanks Lawrence, you are correct, I don't believe it was ever mentioned until now if the welder qualified with backing or not. If backing was NOT used during performance qualification, the welder is qualified with or without backing,and a revision to the WPS is all that would be needed.
Parent - - By PFI (**) Date 06-18-2015 18:37
Carl,

It was actually in my opening post "I was reviewing a WQTR and noticed it was rev'ed to rev 4.  The rev. was to remove the backer from the vee beveled groove test" 

So essentially, that welder is fine and only the WPS needs to be revised to remove the backing bar, the other 7 welders that have welder qualifications that say "with backer only" and are welding on the project would need to be re-qualified.
Parent - By ctacker (****) Date 06-18-2015 19:38
Fred,
The opening post simply said the the WQTR was revised to show no backing, it did not specifically say the welder qualified with backing (could have been a mistake that was corrected). As js55 stated, terminology is important. Like Lawrence, I am not trying to be condescending (as my wife says, reading and writing gets taken in a different context than a live conversation), just trying to help out.

It sounds like you have a PQR/WPS that was qualified with backing, and ( now its clear) a welder qualified with backing, and production welding on one side without backing.
If that is the case, per ASME IX, you just need to revise your WPS to state no backing, and your welder would need to qualify without backing.

Carl
Parent - - By PFI (**) Date 06-18-2015 18:39
Lawrence,

one side only, semiautomatic GMAW spray process in the 1G position

Thanks for all your help !!
Parent - - By Lawrence (*****) Date 06-18-2015 18:59
Ok... Much is now clear.  (Assuming D1.1)

PQR required

Welder performance qualification testing for open root from one side required.

Let me say this as a sidebar:    You sound like a very knowledgeable guy and I don't want to come off as pushy or condescending, but feel it is important to note the following:

While it is possible to make GMAW Spray Transfer open root welds from one side this is not easy.   A PQR can prove the process is possible.  Welder Performance Qualification in addition to regular D1.1 groove testing can be accomplished with training and the right fixturing etc.

Making ongoing production CJP welds with GMAW spray transfer from one side will require some pretty special process controls.   There are some special Tools to make this type of work easier  like Miller RMD and Lincoln STT technologies, but you have not mentioned these and they are not considered "spray transfer"... 

Anyhow....  If you have not done so...  Please consider how things will go *after* the procedures are qualified and the welders are tested...   Think about trials on production work with day in and day out fitup and beveling in mind...     A machined test piece is nothing like a flame cut or ground bevel on a production piece.    

Just some thoughts about sustaining your production quality in a way that reflects the practices you proved your procedures under.    Probably you have already done this and I'm preaching to the choir.
Parent - - By PFI (**) Date 06-18-2015 19:31
Lawrence,

Let me first say I have learned alot about posting and being clear and detailed in my description, I'm sorry this topic has carried on so long.

Few things about your reply ...

1. This is concerning ASME section 9 not AWS D1.1 ( I wish it was because I'm much much more in that code)

2. This is not my PQR, WPS, WQR, I'm reviewing this system.

3. This process has be in place for some 20 years, this is a GMAW process using a fixture and miller rotatory machine, the weld melt through bead is just about perfect on the inside, they have perfected this process to 1/10 volt changes.

4. I'm not concerned with the process, i'm just trying to get the paperwork in order.

You as well sound like a very knowledgable person and I value your input, I'm not in ASME as much as i'm in the AWS codes and it would seem like i need to forget all AWS code while working with ASME!

I hope this helps
Parent - By Lawrence (*****) Date 06-18-2015 19:55
Sounds like you have your ducks and process under control !
Up Topic Welding Industry / ASME Codes / Backer, no Backer, essential variable?

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