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Up Topic Welding Industry / ASME Codes / Material listed on WPS different from PQR
- - By Sarfraz Date 08-01-2015 10:24
Previously the selected material for tanks construction was SA-516 Gr. 70 but to unavailability of selected material in the market, a comparison was made b/w chemical composition and mechanical properties of easily available material i.e. S355J2 and selected for construction instead of SA-516 Gr. 70. Now the question is that we have PQR for SA-516 Gr. 70 and the referenced WPS is listed with new material i.e. S355J2. can we use use these WPS and PQR?
Parent - By CWI555 (*****) Date 08-01-2015 14:11
P355GH  would be the equivalent according to my research.  S355J2 is structural and definitely has a different chemical (in particular min max Mn) and mechanical properties  (in particular % elongation).

The answer would be no it cannot be substituted without qualification which I doubt it would achieve.
- - By 803056 (*****) Date 08-01-2015 14:35
Since the question is posted under the heading of ASME, I suppose I could take a leap of faith and assume this is in regards to an ASME construction code. That would be an idiot's mistake. So, I'm going to ask the obvious question that any newbie should know enough to include in a post of this sort:
1) what construction code is invoked?
2) what is being built and what is the application?
3) what requirements, in addition to those invoked by the construction code, are invoked by local authorities?
4) is notch toughness requirements applicable?

I'm sure there are other questions that can be asked, such as, is the contractor going to use the same welding process that is listed by the WPS, is the same electrode going to be used, is the WPS qualified for the positions and thickness required for production/construction? But, those questions will come to light after we've wasted time and energy making assumption that will prove to be incorrect.

With a few answers to the basic question provided by the person that posted the question, we might begin to provide an intelligent response.

I wonder if I can find Paul Harvey on the radio, "And now, the rest of the story."

Best regards - Al
Parent - - By CWI555 (*****) Date 08-01-2015 17:46 Edited 08-01-2015 17:50
It's tank construction, that was in the OP. The insertion of a structural steel for a pressure steel is a problem by itself.
I highly doubt it has anything to do with ASME code based on introduction of Euro standards, and invocation of tank criteria.
Edit: That's the holiday Inn express answer.
Parent - - By 803056 (*****) Date 08-01-2015 23:02
There you go, making assumptions again.

Al:cry:
Parent - By CWI555 (*****) Date 08-02-2015 02:11
Assumptions based on available information  (which wasn't much). They want something more solid, they need to provide relevant information. One thing for certain, P and S materials don't match up in Euro standards. 516 grade 70 isn't hard to find either. I will be surprised if it were not meant for the outer shell of a double wall tank either, I.E. outer 516 inner 9% nickel A553.

They get what they pay for if they run off with an Internet answer with no research.

My take on it for what it's worth.
Parent - - By Sarfraz Date 08-02-2015 06:35
Dear AI,

Thanks for your time. following are the answers to your questions.

1-Construction Code API-650
2-Storage Tank for Diesel Oil
3-There are no strict requirement by local authorities
4-notch toughness is not requirement

I know that i am asking questions under ASME codes is just because of material i.e. SA-516 that was previously selected for construction and WPS and PQR are being prepared following the ASME section IX.

The PQR is qualified for SA-516 Gr. 70 but this material has not been listed on relevant WPS and contractor is going to use the these WPS and PQR for construction. Do we need to qualify a new PQR for S355J2 material.

Thanks
Parent - - By 803056 (*****) Date 08-02-2015 11:36 Edited 08-02-2015 12:25
It would appear that API 650 permits the use of materials that meet any national standard. However since the WPS must be qualified in accordance with ASME Section IX and since the material proposed is not listed by ASME Section IX, the WPS would have to be qualified for the materials used for construction.

If the owner and their engineering staff approves the materials proposed by the contractor, there may be a "work-around", but local jurisdiction would have to allow such action.

API 650 allows the use of materials that meet ISO 630, including 355, but that doesn't mean one can simply say "this material is the same as ASTM XYZ" without considering the chemistry, method of manufacture (cast, wrought, hot or cold roll, etc.), state of heat treatment (as rolled, normalized, Q&T, etc.), and mechanical properties.

The requirements for requalification of the WPS using the materials proposed for construction is not that difficult to meet. A little inconvenient perhaps, but it is part of meeting the contract.

I believe CWI555 and I are singing from the same page with this one.

Al
Parent - By CWI555 (*****) Date 08-02-2015 16:57
Agreed.
Parent - - By Sarfraz Date 08-04-2015 13:31
The following statements are given in API-650.

Material specifications listed in Section 4 of this standard (API-650) but not included in Table QW-422 of Section IX of the ASME Code shall be considered as P1 material with group numbers assigned as follows according to  the minimum tensile strength specified:

a)  less than 485 MPa (70 ksi)-Group 1;
b) equal to or greater than 485 MPa (70 ksi) but less than 550 MPa (80 ksi)-Group 2;
c)  equal to or greater than 550 MPa (80 ksi)-Group 3

According to above statements, our material i.e. S355J2 which has 470 MPa SMTS is P1 Group 1 material whereas API-516 Gr. 70 is group 2 material as per ASME Sec IX QW-422. therefore we need qualify a new PQR. Am i right?
Parent - By CWI555 (*****) Date 08-04-2015 16:07
You stated SA 516 in your OP, not API 516. I assume that's a typo? As for a new PQR, don't see any way around it.
Parent - By Don56 (**) Date 08-10-2015 20:04
In Section IX group numbers only come into play if impact testing is required.  If impacts are not required you only have to match P numbers.
Up Topic Welding Industry / ASME Codes / Material listed on WPS different from PQR

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