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welder test on C/S for S/S use, using C/S wire to ASME 2

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jasoncc

Materials
Jan 20, 2005
3
If a welder can test using C/S material (P1), and a carbon (F6/A1) filler wire, this qualifies the welder as per ASME IX to weld P8 S/S material using F6 S/S filler wire.

I feel this is not good practice as the welder has not shown ability to clean wire/test piece, maintain temperature, purge test piece, or the skill to manipulate S/S wire.

If this is regarded as bad practice/workmanship, or an unsuitable test for use on corrosion resistant S/S pipework, can the third party refuse to accept this method of testing as being siutable, with technical backup showing why the test is inadequate, because ASME is only a guideline for good prractice?

Or do the certifying authority have to accept and endorse something which may be of questionable technical and practical practice, because the specification says that it is ok?
 
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First off, the ASME B&PV code welder performance qualification method is technically acceptable and has been proven over the years. Your stated concerns have more to deal with the welder either not following a properly qualified WPS, or not following specific instructions that should be in the procedure or work instructions with regards to handling bare wire, cleanliness and over-all weld quality. The welder qualification test is to demonstrate that a welder can deposit sound welds of acceptable quality. This has to be witnessed by someone other than the welder to assure instructions have been followed.

Don't blame the method. If you have concerns over a welder making questionable production welds, you have the right to have the welder re-test.
 
The question is not as specific as it sounds, i know it is allowed to specification, the welder is using an approved WPS/PQR.

The question is ultimately, if the certifying authority deem that the test is not suitable, if the specification allows it, can they refuse to witness/stamp certificates, because they do not consider it good practice. (the arguments on why go on forever)

Does ASME allow the certifying party to basically rule this an un-satisfactory way of testing, because it does say to take into account the effect of mechanical properties/weldability/compatability, and design requirements.

This is for future qualifications, third party have advised that the test would be acceptable to them on C/S pipe if a S/S wire was utilised.

Simply: can the certifying authority not accept this when it is in the specification, or does ASME allow them to reject it if they can show proof of their concerns.

Thanks.
 
After reading your follow-up post, I am confused. Can you provide some specific information as to who you are defining as the certifying authority (is this the Jurisdiction or the Authorized Inspector) and to what specification?

In most boiler and pressure vessel contracts, weld procedures and welder qualifications are provided for review and approval by the owner and Inspector. Welders are qualified for the appropriate weld filler metal and base metal combinations to be used in production. If welder performance qualifications are conducted on carbon steel coupons with stainless filler this is acceptable. If a contractor is simply using carbon steel coupons and using F-6 A-No1 to qualify for all other F- No 6 A –No XX filler metals, this is not correct. If you read QW 404.15 it mentions a change in F No OR a change to any other filler metal. Carbon steel filler is not the same as stainless steel filler metal. Thus, a separate welder performance qualification must be performed for stainless filler metal.
 
My opinion is that ASME gives us the minimum requirements, however, as metengr states, this method of welder qualification has been proven over many years. ASME is not going to 'allow' one to reject this method, or they'd have already changed the practice. That said, there may be contractual provisions for testing welder's or production welds beyond those methods and criteria stipulated by ASME.
For a third party to insist on testing outside of that provided for in the contract, or by any applicable code, is putting him on thin ice.
 
I am working for a test laborotory, we test welders/procedures & supply third party certifying authority (Lloyds / DNV / BV, etc) for testing. Our client is testing welders on C/S pipe using a C/S filler wire to cover for all A1/F6 consumables for the appropriate P number range.

The problem is that the specific thiird party inspector does not think that a C/S butt with C/S filler is an adequate test for welding 316 pipe. (I understand why, his reasoning is justifiable)

**(If a contractor is simply using carbon steel coupons and using F-6 A-No1 to qualify for all other F- No 6 A –No XX filler metals, this is not correct.) Why? (I agree)

In order to settle the argument between our client and the certifying authority i need a better reason than good workmanship, does ASME say anything about this other than QW 431 - general info for F-numbers.

Thanks for the help so far.
 
It is fully legal by code and practical to use carbon steel for stainless for performance qualification. If an organization has a reason to exceed the code, that is fine provided all parties are aware.

QW 431 plainly states the reason for F Number grouping.
"This grouping is made to reduce the number of welding procedure and performance qualifications, where this can logically be done."

I have to keep a seperate certifiaction up for the boilermakers because and I think it is because everone thinks more is better. If a cutomer wants something above the code and it has been agreed upon, fine. If an inspector wants to exceed the code. Not fine. Someone has to pay for it whether it be the end user or the contractor. Exceeding the code because you feel it necessary is wrong.

The purpose of the qualification is to establish that an individual has the ability to show a basic set of skills. NO welder performance test can prepare you for what you run into in the field.

The statement above
"If a contractor is simply using carbon steel coupons and using F-6 A-No1 to qualify for all other F- No 6 A –No XX filler metals, this is not correct. If you read QW 404.15 it mentions a change in F No OR a change to any other filler metal."

indicates that the perception is that QW404.15 would require requalification if the filler metal is changed in any respect even if the fnumber remains the same. QW 433 is the section which permits the use of F6 for all other f6 qualifications.

Even the nickel alloys are grouped together which have extremely different characteristics while welding. 70/30 Coppernickel runs VERY different than F45 yet ASME has deemed it OK to use onefor all the others.

The key to having welders that can handle the task has nothing to do with meeting or exceeding the code. Supervise the testing with someone knowledgable, and supervise the work whileits being performed.


Industry spends quite a bit of money on code committee meetings every year. If all that is required is code compliance, then comply. Industry also pays people to write project specifications and purchase orders. If the requirement is not in the project requirements alot of people have thought it wasn't needed.




Gerald Austin
Iuka, Mississippi
 
Do I understand this situation correctly?

A welder qualifies to a WPS using a Code-acceptable optional electrode. No Code problem at this point.

The Jurisdiction required Code compliance. The welder has met the Code requirements at this point. Still no problem yet.

The Client's third party Inspector's opinion is that the Code is wrong in allowing the welder to qualify using the optional electrodes.

Sounds like a personal problem to me. The Inspector needs to get over it, have the contract changed to his liking or ask for the Code committee to make a change in the Code requirements.

Steve Braune
Tank Industry Consultants
 
You are dead on Steve, as it sounds very much like a client's inspector with a personal problem. But we all know client's inspectors never have god complexes and bad attitudes...

Brian

Opinions expressed are my own and are not those of the company.
 
I had a few situations on the subject,
The Code allows the carbon steel performance test and use the welder on ss of similar as F6 xxxx
It can be an Eng problem when most of your work is on SS, the AI can invoke the subject test and require a ss test,
Do not foget tat if it is an Eng practice, the AI is allowed to enforce it (if is for a reason), It has happened to me many times.
Read the preamble of the Code, te AI is the boss (if and for a reason)
Here is the deal, if the vessel is already welded, you can actually redo the performance on ss and get away with it.,
since your welder is already "legal" per Code I se no problem to do the test after.
GB
 
WPS Qualification: I weld plate 1 1/4 for cs. wps

Question #1:
QW 403.6 states the minimum base metal thickess qualified is the thickness of the test plate or 5/8 whichever is less. QW 451.1 table states: min. 3/16
So what is the min. thickness qualified on my 1 1/4" plate 5/8 or 3/16?

Question#2:
What is the minimum thickness for welder qual. on this plate? Or as per QW 452.1(b) there is no minimum.

Question#3
QW211: Qualification on plates also qualifies for pipe welding and vise versa. So my 1 1/4 weld wualifes for pipe welding? what diameters? all diameters?
Thank you.
Bogdan Grabov
 
1 ) 5/8 " is for impact tested applications only. If you qualify the PQR with impact tests the impact qualified WPS is limited to 5/8" minimum. However, you have the option of supporting a non impact qualified WPS with the same PQR which is good down to 3/16".

2 ) Min thickness for welder qualification for this WPS is 1/2", provided your welder completes the joint with a minimum of 3 layers.

3) I'll have to verify tomorrow but I'm thinking that plate is good for any diameter, however your welder qualifications are limited. I'll get you the pertinent paragraphs tomorrow.

 
We have to accept the requirements / qualifications as per Code. In case of any dobut, Inspector may ask for additional / re qualifications of welder
 
bit confusing but I am reading your follow up, it is not acceptable to use c/s pipe with ss wire unless is part of your pQR and WPS, if you have a procedure for that combination,
you are allowed I see no conflict here.
It is not a ussual combination but... it is not my call.
there are welds c/s to ss using ss wire but I have never seen all c/s material welded with ss wire; I do not see the purpose.
ER
 

Pl refer QW 416,Welding variables-- welder perfomance.
When there is a change in Pno & Fno, requalification is required
 
QW-423.1 allows base metal that is different from the WPS to be substituted for the welder qualification test.
 
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