qualified base metal thickness

[moe27]

FCAW P1 material to P1.
I will be welding a 3/8" thick lift lug (CJP) onto the side of a 2" plate (TEE JOINT).
We have a WPS qualified in a range of 1/4" to 1/2" base metal, can I use this procedure on this joint and if so where in the code may I find this answer?
Which thickness takes precedence over the other?

Thank you,

 

[weldtek]

moe27,
You say a tee joint. Are you making a fillet weld only or, does it call for a groove weld with a fillet on top?
Assuming your previously qualified WPS is for groove welds and all other essential variables are adhered to and, if you're making just fillet welds, you may use your existing WPS to support this work. I'm basing my response on QW 202.2(c)

 

[weldtek]

moe27,
I said, 'you may use your existing WPS to support this work' but I should have said you can use your existing PQR to support this work. Depending on how it is written, you may need to revise your existing WPS, or create a new one.

 

[moe27]

My WPS supports CJP and 1/4" to 1/2" material thickness and I am beveling lug for a CJP weld.
Is my concern with the 3/8" material thickness or the 2" thick material that the lug attaches to??

Thanks

 

[metengr]

The lug is full penetration (groove and small fillet) welded to the 2" shell thickness. You need a WPS that supports 2" thick base material thickness.

 

[moe27]

Thank you Metengr for your response.

Where may I find the supporting text in ASME sec IX Code?

Thank you

 

[metengr]

QW-202.2 (a). I did think about the approach of considering this a fillet weld from both sides of the lug to achieve a full penetration weld. However, this would be a stretch. If you considered a partial penetration weld from both sides of the lug, this would fall under QW-202.2 (b). However, this would require qualification on base material 1.5" thick - see below

(b) Qualification for Partial Penetration Groove Welds.
Partial penetration groove welds shall be qualified in accordance
with the requirements of QW-451 for both base
metal and deposited weld metal thickness,except there
need be no upper limit on the base metal thickness provided
qualification was made on base metal having a thickness
of 1-1/2 in. (38 mm) or more.

 

[DekDee]

moe27,

QW-202.4 Dissimilar Base Metal Thicknesses.
WPS
qualified on groove welds shall be applicable for production
welds between dissimilar base metal thicknesses provided:
(a) the thickness of the thinner member shall be within
the range permitted by QW-451

(b) the thickness of the thicker member shall be as
follows:
(1) For P-No. 8, P-No. 41, P-No. 42, P-No. 43, PNo.
44, P-No. 45, P-No. 46, P-No. 49, P-No. 51, P-No.
52, P-No. 53, P-No. 61, and P-No. 62 metal, there shall
be no limitation on the maximum thickness of the thicker
production member in joints of similar P-Number materials
provided qualification was made on base metal having a
thickness of 1⁄4 in. (6 mm) or greater.
(2) For all other metal, the thickness of the thicker
member shall be within the range permitted by QW-451,
except there need be no limitation on the maximum thickness
of the thicker production member provided qualification
was made on base metal having a thickness of 11⁄2 in.
(38 mm) or more.
More than one procedure qualification may be required
to qualify for some dissimilar thickness combinations.

Hope that helps,
Cheers,
DD

 

[david339933]

Section IX does not address your question. You are welding the through thickness of the lifting lug (3/8")...so as far as Sec IX is concerned the WPS you described is sufficient (Assuming this is the only variable in question). You need to investigate the Code of construction for any restrictions. Much like Sec VIII has requirements for corner joints.

Why not weld a 3/8" reinforcing pad to the 2" plate and then weld the lug to it....everybody wins.

 

[DekDee]

david,
I respectfully disagree.
Here are a couple of interpretations

Interpretation: IX-86-89
Subject: Section IX, QW-202.4
Date Issued: June 2, 1988
File: BC88-O89
Question: When employing a groove-weld WPS to join flat plates of dissimilar thickness in a
corner joint, is it a requirement of QW-202.4 that both the thicker and thinner members must be
qualified within the range permitted by QW-451 unless the alternative provided in QW-202.4 is used?
Reply: Yes.

Interpretation: IX-95-12
Subject: Section IX, QW-202.4, Dissimilar Base Metal Thicknesses
Date Issued: March 17, 1995
File: IX-95-12, IX-95-13, IX-95-14
Question: Does QW-202.4 include butt joints and corner joints when joining dissimilar base metal
thicknesses when prepared with a groove?
Reply: Yes.

Interpretation: 1X-98-20
Subject: QW-202.4(b), Dissimilar Base Metal Thickness
Date Issued: June 8, 2000
File: BC99-539
Question: When welding a corner joint with dissimilar base metal thickness, the thickness of both
members must be within the qualified thickness range of the WPS(s) being used. How is the thickness
for the thicker member defined in sketches (a), (b), and (c) below?

I was unable to post the diagrams but the intent of the code is quite clear - both members of a corner joint must be within the required thicknesses,
Regards,
DD

 

[david339933]

All very good interpretations, however they refer to corner joints and butt joints. This situation is neither. I merely referred to corner joints as an example of construction codes imposing more restrictions on joint geometries. IMO This is a tee joint. The sketches to which you refer also do not represent this joint configuration.

 

[DekDee]

C'mon David,
If I weld a 1" (25 mm) plate at right angles on the end of a 4"(100 mm) plate with a single bevel or double bevel it is classed as a corner joint.
If I move the 1" member away from the end of the 4" member it then becomes a Tee joint.
What is the difference between the two when it comes to the relationship between the thinner member and the thicker member ? - nothing !

The clause I noted above ( QW 202.4) states groove welds - a groove weld can be a corner joint or Tee joint.

The OP requires a groove weld (whether it is a corner or tee joint) between 3/8" and 2" material and therefore must comply with the requirements of QW 202.4
Regards,
DD

 

[Mechanimal]

I agree with David.

I think a closer interpretation would be here (IX-80-67)

Link

The governing thickness would be the 3/8", "set-on" the shell.

 

[DekDee]

mechanimal,
The interpretation you have posted clearly states both base metal thicknesses must be qualified.

ATTENTION

The foregoing Interpretation has been further considered, and the following corrected Interpretation sent to the inquirer.

Correction Issued: March 12, 1981

Question: When nozzle or branch connections are attached to the wall or head of a pressure vessel, what are the basic criteria establishing procedure and performance qualification?

Reply: For groove weld procedure qualification, the base metal thickness range for all base metals being joined in addition to the deposited weld metal thickness range for each process used must be qualified in accordance with QW-451 (see QW-202.4). Also, see exemptions in QW-202 for fillet weld procedure qualifications.

Regards,
DD

 

[weldstan]

Because it's a groove weld your PQR must be qualified with at least one member being 1" thick.