Weld metal tickness range qualified for ASME IX procedures 2

[engr2GW]

Hi,
I have two WPS,

1. First one qualified with 2" 0.218 coupon, from QW451.1 for weld metal thickness and base metal thickness, this coupon falls into the base metal range of 1/16" to 2T (0.436"), and the weld metal max. is 2t, does that mean that the range for the weld metal is 1/16" to 2t also? in other words, what's the minimum for the weld metal range and is 2t=2T?

2. and the other with an 8" 0.500" coupon, from QW451.1 for weld metal thickness and base metal thickness, this coupon falls into the base metal range of 3/16" to 2T (1.000"), and the weld metal max. is 2t, does that mean that the range for the weld metal is 3/16" to 2t also? in other words, what's the minimum for the weld metal range and is 2t=2T?

Thanks a lot.

 

[metengr]

1. First one qualified with 2" 0.218 coupon, from QW451.1 for weld metal thickness and base metal thickness, this coupon falls into the base metal range of 1/16" to 2T (0.436"), and the weld metal max. is 2t, does that mean that the range for the weld metal is 1/16" to 2t also? in other words, what's the minimum for the weld metal range and is 2t=2T?

Assuming for a single welding process, the qualified weld metal deposited thickness range is 1/16" up to 2t.

2. and the other with an 8" 0.500" coupon, from QW451.1 for weld metal thickness and base metal thickness, this coupon falls into the base metal range of 3/16" to 2T (1.000"), and the weld metal max. is 2t, does that mean that the range for the weld metal is 3/16" to 2t also? in other words, what's the minimum for the weld metal range and is 2t=2T?

Assuming for a single welding process, the qualified weld metal deposited thickness range is 3/16" up to 2t.

 

[engr2GW]

Thanks metengr:
1. so the "t" is the same as "T" of base metal range right? in other words, 2t = 2T right?
2. while that makes perfect sense for 1 process, I do recall that a one of the 2" is TIG and SMAW and one of the 8" as GMAW and SMAW, so will the range below be correct
a. 2"
i. TIG root: 0.062" - 0.125" (t to 2t right?)
ii. SMAW fill-cap: 0.156" - 0.311" ( not sure the min is right..)

b. 8"
i. MIG root: 0.062" - 0.068 (t to 1.1t right?)
ii. SMAW fill-cap: 0.1875" - 0.874 (with the 1.1t limitation, the max addition becomes 0.942" instead of 1" right? I doubt my understanding for now, help me out please.
Thanks

 

[Guest102023]

Good answers, metengr, but this kind of number-crunching is an example of why it is usually better to qualify with single process per PQR, and sometimes better with plate rather than pipe. Especially when supplemental testing is required. Unless perhaps if small-diameter pipe is all you will ever weld.

 

[Kiwi2671]

metengr,
With all due respect there is no minimum limitation on "t" - deposited weld metal, only maximum.

Example 1:
Interpretation: IX-83-64
Subject: Section IX, QW-451
Date Issued: May 9, 1983
File: BC83-222
Question (1 ): A 1 ‘/z in. thick double V-groove joint test coupon was welded using SMAW for 3/4 in. and GTAW for 3/4 in. What is the range of base metal qualified?
Reply (1 ): Per QW-451, the range of base metal qualified is 3/16 in. to 8 in.
Question (2): What is the range of deposited weld metal qualified for each process?
Reply (2): Per QW-451, the maximum range of deposited weld metal qualified is 8 in. with no minimum limitation.

Example 2:
Interpretation: IX-83-81
Subject: Section IX, QW-45 1.1
f*-.
Date Issued: September 19, 1983
File: BC83-395
IX-83-81
Question (1 ): In the Winter 1982 Addenda to Section IX, the minimum values for “Thickness t of Deposited Weld Metal Qualified” in QW-451.1 were deleted. Does this mean there are no minimum thickness qualifications for deposited weld metal?
Reply (1 1: When determining the minimum thickness qualifications per QW-451.1, Notes (1) and(2) must also be considered. In those cases where the further limitation of these Notes does not apply, there is no limit on the minimum thickness qualification.

Notes 1 & 2 of QW451.1 must be taken into account but I can see no reference to clauses noted in the OPs original posting,
Regards,
Kiwi

 

[metengr]

Correct. I was thinking of base material thickness because this sets the minimum for weld deposit thickness.

 

[Kiwi2671]

metengr,
Now you have got me confused.
If there is no minimum for deposited weld thickness how can minimum base metal thickness have anything to do with it.
Hypothetically I weld a 1/2" (12.7 mm) plate.
That qualifies me for 3/16" (4.8 mm) minimum for base metal.
Deposited weld metal qualified is 2 x "T" maximum (with no minimum).
What is to stop me welding 1/16" thick only deposited weld metal or 1/8" thick.
I realise it would give you an incompletely filled groove if it was single process and a CJP but would it not be applicable to a PJP ?
Regards,
Kiwi

 

[metengr]

Sorry, I did not make myself clear. Normally, the minimum weld deposit thickness would correspond to the thickness of the thinner of two materials being joined to ensure a full penetration butt weld. The reason the minimum weld deposited thickness was removed as a code change was to encompass tack welds with a WPS, and to address partial penetration groove welds, since Section IX is a service code book.

 

[engr2GW]

Thanks everyone for all the post,

now that it's fairly clear that there's not requirement for minimum thickness of weld metal qualified, here's a scenario:

I welded a 2" sch. 80 (0.218 wall) pipe with TIG root and stick fill-cap. base metal range is 1/16 to 2T. weld metal max is 2T = 0.436", but since this is two processes, how do I distribute the max for the TIG and root, do I just say max for TIG is 0.436" and max for stick is also 0.436? or.....??

Thanks a million.

 

[engr2GW]

Or I'm requiered to determine the thickness of each in the joint design as "t" and use 2t for the max for each

 

[weldtek]

The approximate thickness of each process should be documented on the supporting PQR. Use that to determine the applicable range for each process.

 

[Bocephus50]

Was the Mig above "short circuiting" process? Short circuiting is 1.1T for max range. But, for spray arc, globular, pulsing methods the max T is still 2T.

You do not count "reinforcement of welds" just base metal thickness. Acceptable weld reinforcement sizes come from the Code of construction.

 

[Kiwi2671]

mysarah,
Follow weldteks advice.
When you perform the procedure qualification test measure the amount of GTAW you have put in. - Record it.
Subtract the GTAW from the base metal thickness and that will give you the SMAW thickness - Record it.
Qualified base metal will be 1/16" to 2 x "T" max
Deposited weld metal will be
GTAW = 2 x "t" max
SMAW = 2 x "t" max
If your 2 x "t" + 2 x "t" = 2 x "T" then you are all good.
Hope that helps,
Regards,
Kiwi