QW452.1 Cover THICKNESS OF WELD METAL QUALIFIED.
But I understand only maximum.
My question is: What is minimum Thickness Qualified?,
for example 1 in. is usually in test with groove, en WPQ only point 2 in as maximum and the minimum thinkness.


Thank you for you aswer

Hi Dayanara,

there is no limitation for the minimum qualified thickness of the deposited weld metal, neither for WPQ (see table QW-452.1(b) nor for PQR (see table QW-451.1).
Unfortunately you are not right with your example. Please have a look at the table QW-452.1(b). For a test coupon with a thickness of the deposited weld metal of 1 inch the maximum qualified thickness is all to be welded.

Please note that the base metal thickness is not an essential variable for a WPQ (except for OFW).

_________________
Kind regards,
Juergen Fleischfresser

Hi Juergen
Thank for you aswer.
But I have no understand.
Please help me.
In table 451.1 is only for Welding Procedure.
For example:
1.- I qualified with thickness 20 mm. cupon test, I qualified for weld 5 mm. minimum up to 2T (40mm) and maximum weld metal is 2T. my interpret is conformance .
2.- For welder,in table 452.1(b).
I qualified with 20 mm. thickness, the welder qualified for weld 40 mm. maximum for table thickness weld metal in the cupon is: all = 2T.
Thank you.

Dayanara

Hi DAYANARA,

the thickness model acc. to ASME IX consist of two thicknesses (one of the main differences to the European welding standards):
1.) Thickness of the base metal (capital letter T)
2.) Thickness of the deposited weld metal (lower case letter t)

a) WPQ (table QW-452.1(b))
For a WPO the deposited weld metal thickness only is an essential welding variable (except for OFW)
The qualified weld metal thickness is a function of the actual deposited weld metal thickness t (per each process) only and not a function of the base metal thickness T of the test coupon.
Please have a look at the table QW-452.1(b). You find in the head line of this table and in Note 1) and 2) the lower case letter t only.

Your example test coupon with 20 mm deposited weld metal (regardless to the thickness of the base metal):
1.) Deposited weld metal consist of max. two layers and qualifies therefore for a weld metal thickness of max. 40 mm without limitation for min. (regardless to the thickness of the base metal)
2.) Deposited weld metal consist of min. three layers and qualifies therefore for a weld metal thickness of max. all to be welded without limitation for min. (regardless to the thickness of the base metal)


b) PQR (table QW-451.1)
For a PQR are the deposited weld metal thickness t (per each process) and the base metal thickness T essential welding variables.
The qualified weld metal thickness is a function of the actual deposited weld metal thickness and of the actual base metal thickness (for T min. 19 mm) of the test coupon.
The qualified base metal thickness is a function of the actual base metal thickness of the test coupon only.

For clarification I have changed your example as follows:
Test coupon with 10 mm GTAW and 20 mm SMAW deposited weld metal and 30 mm base metal thickness:
(1) Deposited weld metal thickness 10 mm qualifies for max. 20 mm without limitation for min. (t qualified = 2 x t if t welded <19 mm)
(2) Deposited weld metal thickness 20 mm qualifies for max. 60 mm without limitation for min. (t qualified = 2 x T if t welded min 19 mm)
(3) Base metal thickness 30 mm qualifies for 5 through 60 mm

Please note if toughness test are a design code requirement all supplementary essentials are applicable. This means the qualified base metal thicknesses of the examples above have to change in 16 mm through 60 mm (for min. qualified T see QW-403.6).

I hope that helps to clarify what the thickness model of ASME IX means.

_________________
Kind regards,
Juergen Fleischfresser