Qualification between different codes

Date 02-14-2011 03:24

eeeeehhhhhhh

How can you fabricate according to code if you cant remember, which code you are working to?
How about PED?

3.2

By Boon

Date 02-14-2011 07:06

Sorry, just that I didn't have the drawing with me when posting.
The welding quality is EN25817-C.
No PED requirement.

By G.S.Crisi (****)

Date 02-14-2011 18:24

I've always said that qualifying codes and standards should be taken with good sense (horse sense, I've seen it written often). I'll give an example.
Back in my days of erector enginner, I was in charge of the erection of a crude and vacuum oil refining plant. The last circumferential welds of the crude tower and the vacuum tower, as well as a lot of welds on partially prefabricated piping were to be done at the job site. Therefore, the welders were qualified per ASME IX.
But a lot of platforms, stairs and walkways welds were also to be done at site. In this case, as they are structural steel, AWS D.1 should have been the qualifying standard. However, at a meeting with the client, I argued that welders who are capable of welding crude and vacuum towers and high pressure and high temperature piping (a much more stringent service than just a stair) are of course capable of making a not very complicated structural steel welding. Therefore, the welders needed not to be qualified under AWS D.1
The client accepted my reasons and the refinery has been just taken out of operation for technical obsolescence, after 40 years of service.
Giovanni S. Crisi
Sao Paulo - Brazil

By Joey

Date 02-21-2011 07:21

Considered lucky…if the steel structures collapsed because of poor weld quality, do you think your reason will be acceptable to the Judge?

By G.S.Crisi (****)

Date 02-21-2011 19:48

Joey,
A welder who's capable of welding a vacuum tower and high pressure hydrocarbons piping in oil refineries is of course capable of making good quality welds in stairs and walkways.
As fat as the man climbing the stair might be, the weld is subjected to a much more soft service than a fully radiographed vacuum tower or high pressure and temperature hydrocarbons.
Giovanni S. Crisi

By Joey

Date 02-22-2011 02:15

Prof not to be sarcastic…may I ask you, do you think you are smarter than a fifth grader?

Will you feel happy when your Dean transferred you to the elementary school to teach? I think your morale will be affected as well as your performance.

Are you aware that there are so called Class A welders who failed a simple fillet weld test.

The welders you recommended for welding of handrail, platform, ladder have no valid performance certificates meant for the job. I will not do the same approach if I’m working for contractor. It will be good to have a proper documentation to avoid non conformances during auditing.

By Shane Feder (****)

Date 02-22-2011 03:25

Hi Giovanni,
There is an excellent post from Al (803056) regarding welders who are qualified to weld groove welds not being able to pass a simple fillet break test.

http://www.aws.org/cgi-bin/mwf/topic_show.pl?pid=163617;hl=Fillet%20Break%20Test

This is an excerpt from that post.
I just finished testing welders (15 welders total) for two different companies using the T-fillet break test on 1/2 inch plate. The test requires a single pass fillet with a 5/16 inch leg and a stop and start half way along the joint. Eleven of the welders had passed the grooved butt joint previously. Not one of the eleven welders (with certs for groove welds) passed on their first attempt, not their second, a few passed on their third attempt. Granted, I'm not easy on the boys, once they fail the initial test they have to pass two consecutive practice break tests before I will administer a second test. The second test consists of two more test plates, both of which have to pass the break test. None of the 15 welders passed the fillet test without some hands-on show and tell. I should have asked for the scrap left over after the testing as payment. I would have been able to take an extra week of vacation!

I have said this for years and I will continue saying, "There is a disconnect between ASME, AWS, and other welding standards when it comes to fillet welds." The ability to pass a grooved butt joint test has little bearing on the welder's ability to pass a "simple" fillet break test. While most codes and standards permit the welder that has passed the grooved butt joint to weld fillets without additional testing, the plain truth is, few of them will pass the fillet break test.

Regards,
Shane

By js55

Date 02-22-2011 14:03

Shane,
There will always be disconnects between governing bodies of differing industries. There is a disconnect between ASME Section I and ASME Section VIII as pertains to many things. PWHT(for example I have have always thought the PWHT requirements for Section I oddly lenient as compared to B31.1 until I learned more about the reasoning behind the requirements), impact testing, etc. The people that sit on these committees will evaluate requirements based upon the application of their industry sector. Sometimes they get it right, sometimes they don't. Far more often they err on the side of caution. sometimes extreeme caution, until more evidence permits greater leniency.
If one were to try and impose upon ASME an AWS type fillet testing regime bring evidence of real application problems, not testing deficiencies, and expect an onslought of questions and real world challenges to your proposed change.
I have seen evidence myself of committees responding very quickly to consistent failure data.
And of course, the argument can be reversed. I have always thought that the positionality requirements for procedure quals in D1.1 ridiculously stringent. There is little emerical evidence I can think of to support the idea of positional variance in weldments properties (beyond scatter band data) when utilizing a minimum requirment tensile/bend test regime, once you remove issues of welder ability. And should welder ability be a determinative for procedure qual?

By Shane Feder (****)

Date 02-22-2011 23:55

Jeff,
My apologies for the confusion.
That whole post is a copy and paste of Al's earlier posting, not my opinion.
I just posted it because Al noted (and I have seen numerous examples) of welders that can pass a groove weld test but not pass a fillet weld test.
Regards,
Shane

By js55

Date 02-23-2011 13:31

Shane, no problem. I thought I remembered the thread. Al is correct. I also believe that a groove weld ability is not necessarily a demonstration of fillet ability. However, I am not sure of the practical significance of it.
There are other instances of economies that do not exactly coincide.
My point would be that if one was to expect ASME to homogenize with AWS over the issue then there would need to be some consistent service failure phenomena to get them to change from something that has ostensibly worked for a long time.
It would be an interesting debate if someone were to bring the issue to Section IX.
Any volunteers? :)
I volunteer Al.

By G.S.Crisi (****)

Date 02-22-2011 18:15

Pressure vessels have nozzles. Nozzles have reinforcing plates around them. Renforcing plates are welded to the vessel wall on their outer (peripheral) side by means of fillet welds.
I would like someone to answer the following question: does this means that the welder who welds the reinforcing plates must be qualified by AWS instead of ASME ? After all, he's doing a fillet weld .............
Giovanni S. Crisi

By Superflux (****)

Date 02-22-2011 22:34

ASME IX, 2007 QW 303.1 page 53 ..."welders ....who pass the the required tests for grove welds in the test position ... shall be qualified for the positions of groove welds and fillet welds shown in table QW 461.9"

By Shane Feder (****)

Date 02-23-2011 00:09 Edited 02-23-2011 00:15

Guys,
The issue is the anomoly in the codes - whether it is AWS or ASME that Al raised and Giovannis post brought to light again.
It is the Code Committees (AWS / ASME) understanding that a fillet weld is easier than a groove weld - qualify on groove and you are automatically qualified on fillets.
How then is it that numerous welders who can pass the groove weld fail the fillet break test and / or macro ?
If I remember correctly wasn't the Alexander.L.Kielland Oil Rig disaster in the North Sea caused by a 6 mm fillet weld (non - load bearing) ?
Quick check on Google
http://en.wikipedia.org/wiki/Alexander_L._Kielland_(platform)

Regards,
Shane

By js55

Date 02-23-2011 13:34

Shane,
Therein lies the problem with the argument. In order for there to be a code change you cannot just rely on a failure you have to connect the perceived testing deficiency to the failure, otherwise you are not addressing the cause. You are assuming a cause and addressing a theory.

By 99205

Date 02-27-2011 08:22 Edited 02-27-2011 08:30

"The investigative report concluded that the rig collapsed owing to a fatigue crack in one of its six bracings (bracing D-6), which connected the collapsed D-leg to the rest of the rig.[2] This was traced to a small 6mm fillet weld which joined a non-load-bearing flange plate to this D-6 bracing. This flange plate held a sonar device used during drilling operations. The poor profile of the fillet weld contributed to a reduction in its fatigue strength. Further, the investigation found considerable amounts of lamellar tearing in the flange plate and cold cracks in the butt weld. Cold cracks in the welds, increased stress concentrations due to the weakened flange plate, the poor weld profile, and cyclical stresses (which would be common in the North Sea), seemed to collectively play a role in the rig's collapse."

Over 100 people died on that rig because of crappy welds. I tell every new welder I come across to, "lay that bead like your life depends on it".

By dbigkahunna (****)

Date 02-23-2011 00:13

Sorry there scooter, but if you qualify ASME Section IX with a 6G grove weld with pipe, you are qualified to make filet welds. By Section IX if you test and qualify with pipe in that position you can make any weld in any position limited by the essential variables.
I work a lot with API 650 and it allows welders to be qualified AWS D1.1 for structure and attachment welds. But these welders are not allowed to weld on the tank itself. The tank welders can weld the plate as well as the attachment welds. A lot of the prefrabricated work sent from the erector's shop are welded by D1.1 welders. But all the field welders are qualified ASME Section IX.

By G.S.Crisi (****)

Date 02-23-2011 00:40 Edited 02-23-2011 17:46

Hooray!
Then, according to what Superflux and dbigk say, the client and me were not that wrong when we allowed welders qualified by ASME IX to weld platforms, walkways and ladders !
Gentlemen, I'm talking of platforms, walkways and ladders in an oil refinery, that must whistand the weight of a couple of guys, as fat as they might be; I'm not talking of the Sears tower in Chicago nor the 600 meters tall hotel in Dubai .........
Giovanni S. Crisi

By Joey

Date 02-23-2011 03:16

Prof, it is definitely not wrong when code or project specification allows it. But you are the one who said that AWS D.1 is the qualifying standard. So I reiterate that the welders you recommended for welding of handrail, platform, ladder have no valid performance certificates meant for the job, as required.

You’re proud to state here that you did not follow the project requirement because you have not used welders qualified in accordance with D1.1 (sorry D.1). Perhaps at that time, you are thinking that welders qualified to ASME IX are superior than those welders qualified in D1.1. (I guess, sorry)

By Superflux (****)

Date 02-23-2011 05:42

G.S.,
"a couple of guys, as fat as they might be; " Hmmm. Might want to take careful consideration in your calculations. A couple of 100 kilo plus maintenance employees with tools might come to some serious loading issues. Don't forget the side load on the hand railing too while they are hiding from supervision and talking Sports statistics!

By Joey

Date 02-23-2011 03:09

Thank you scooter for reminding.

You should have said that in API 650, it states “Welding procedures for ladder and platform assemblies, handrails, stairways, and other miscellaneous assemblies, but not their attachments to the tank, shall comply with either AWS D1.1, AWS D1.6, or Section IX of the ASME Code, including the use of standard WPS”.

The welders and welding operators who weld pressure parts and join nonpressure parts, such as all permanent and temporary clips and lugs, to pressure parts shall be qualified in accordance with Section IX of the ASME Code.

So what is surprising when it is written in the code??? There is no argument, right?

Tell me scooter, if you have this option. Which code you will use to qualify your welders for welding of ladder and platform assemblies, handrails, stairways, and other miscellaneous assemblies? D1.1 or ASME IX?...which one has stringent acceptance criteria and longer test plate coupon? Teach me please :)

By dbigkahunna (****)

Date 02-23-2011 12:14

What is the definition of stringent acceptance criteria?
Does a welder who passes a 3 plate test have more stringent acceptance criteria than one that qualifies in 6 G with 8 inch SCH 80?
Does the welder who passes using 6 G R 2 inch SCH 80 have a more stringent acceptance criteria than the welder doing the 3 plate test?
And the acceptance of D1.1 in 650 work has applied only in the recent editions of the standard.
The option only comes on structure welds and not any weld attached to the shell.
A welder qualified to D1.1 can weld on the stairway tread, handrails, and other parts, but cannot make a weld to the shell itself.
A welder qualified to Section IX can weld on the stairway tread, handrails and other parts AND can attach these members to the shell.
A fabricator could have the bulk of its shop welders qualified to D1 with a few qualified to Section IX as the bulk of the welds sent out are structure. All the field welders are qualified to Section IX as the majority of the welds will be attached to the shell.

By G.S.Crisi (****)

Date 02-23-2011 18:41

Gentlemen,
In Brazil we say: "You are making a tempest in a glass of water".

Suppose a structural steel fabrication shop specialized in platforms, handrails and stairs for industrial plants (I've known more than one back in my days of project engineer). It's more than obvious that its welders must be qualified by AWS D1.1.
Suppose a platework fabrication shop specialized in pressure vessels (I've known more than one back in my days of project engineer). It's more than obvious that its welders must be qualified by ASME IX. Now, pressure vessels are usually delivered to the job site with all their gussets attached to it. For those who don't know, gussets are small plates welded to a rectangular plate, which is in turn welded to the vessel wall. Platforms, ladders and walkways are attached to the gussets, frequently by bolting.
Gussets are welded to the rectangular plates by means of fillet welds. The rectangular plates are welded to the vessel wall by means of fillet welds. So, welders qualified by ASME IX should be able to make a decent fillet weld. If they don't, put them to practice making only fillet welds during a week, until they learn.

What I tried to say (English being not my mother language, possibly with no success) was not that ASME IX is superior to AWS D1.1, nor viceversa; neither was it that AWS D1.1 could be replaced by ASME IX. What I tried to say is that before starting the erection of a crude and vacuum oil refinery, where some of the 100% radiographed circumferential welds on both towers were to be done at site; and so were plenty of piping welds carrying hot and highly pressurized hydrocarbons (danger of fire or explosion if a weld leaked), me and the client sat at the same table, and after a short discussion agreed that the few structural welds that were to be done at site (all of them belonging to platforms, walkays and stairs) could be done by the ASME IX approved welders; with no need to requalify them under AWS D1.1. The refinery has been taken out of operation for technical obsolescence after 40 years of good services.

Joey, I'm not proud of having infringed any standard. What I tryed to do, apparently with no success, was to share my personal experience with the other people of this Forum.
Giovanni S. Crisi

By Joey

Date 02-24-2011 09:57

You have the habit of blaming your mother language whenever you have been ticked off. But indeed you can write a good english phrase :) and know to use the hip-hop-hurray. You make me confuse Prof. Crisi

No way that I have exaggerated the thread . The reason I asked “do you think your reason will be acceptable to the Judge” is because when accident happened, your lawyer will surely get all the supporting documents to prove that you have complied with the code / specification requirements. Are you not happy that I have reminded you in this forum?

Well, let see how purely you are..…..do you still remember in the past thread that you have told me to put my hand on the bible and swear during inspection work – That was extremely ridiculous Professor, worse than exaggeration!!!

By qcrobert (***)

Date 03-01-2011 19:48

If welding to a specific code, the PE (Engineer of Record) will note that on the drawings.

I have seen piping drawings that dictate that welding shall be done to ASME Sec IX and that the structural (stairs, handrails, platforms, etc) shall be done to AWS D1.1.

However you may get a written varience from only the Engineer of Record to allow your ASME Sec IX qualified welders to perform welding on such structural parts with this written varience.

Have done so many times,
QCRobert