AWS Code D1.2 1990 PQR

By SteveB Date 11-20-2001 13:03

I am presently working on a job in accordance with the 1990 edition of the D1.2 aluminum welding code, and their is a differance in opinions on the plate thickness qaulified range in table 5.4. We had previously qualified a welding procedure for a full penetration weld on a 1/2" plate. Using the same variables we then welded a 1/2" depth of penetration partial penetration weld in a 3/4" coupon. And in accordance with 5.17.3.3 we performed the three macroetch tests. My question is What is the minimum thickness qualified? Is it the plate thickness qualified or is it unlimited? It is my opinion that the minimum thickness qaulified is the plate thickness used in the test and the maximum is unlimited. The opinion of the welding engineer is that both are unlimited. Any opinions on this matter would be of interest to me Thank you Steve in cincinnati.

By DGXL

Date 11-21-2001 03:37

Dear SiC,
I respectfully disagree with your Engineer on this one.

1. For the 1/2"T CJP groove weld previously qualified:
minimum plate T qualified = 1/4" (1/2 of T) [Table 5.3]
maximum plate T qualified = 1" (2 x T) [Table 5.3]

2. For the 3/4"T PJP groove weld qualified:
minimum plate T qualifed = Unlimited [Table 5.4]
maximum plate T qualified = Unlimited [Table 5.4]

My question to your Engineer is as follows: "Will you be able to weld a piece of material with a T of 0.062" using the same WPS welding parameters you used to qualify the 1/2" or 3/4" plates?"
Please read the WPS limitation of variables which denote:
arc voltage/amperage tolerance = plus/minus 15%
arc travel speed tolerance = plus/minus 25%
(5.2.4 and 5.16 in it's entirety)

Please note also when they prepared the specimens for the mechanical testing of the PJP groove weld, the material in excess of the required weld size (E) was removed (5.9.1.4).

Let me know how you do on this one.

By SteveB Date 11-21-2001 14:01

Well it appears as if you agree with the welding engineer also. The minimum thickness that I am refering to is in the partial penetration weld your item #2 agrees with him and that is that the minimum and maximum thicknesses for a partial penetration weld are unlimited. If one looks at table 5.4 in the extreme right hand side of the table it states.
"Plate thickness Qualified" In the area normally reserved for the min, and then there is a comma followed by "Max" and below the line it states unlimited. My interpretation was that the minimum thickness qualified would be the thickness of the actual test and that the maximum thickness is unlimited. Thank you for your response Steve