How many Charpy V specimens? 5

[m3brunof]

I searched the forums but could not find an answer.
I'm qualifying a WPS with GMAW and FCAW on 1-1/2" P1 gr2 plate. GMAW root and FCAW filler and cover passes. Charpy testing will be at -50 F.
This will be done per B31.3.
From what I've read, it looks like I will need 3 specimens per set of impact tests. So how many total charpy tests do I need?
Is it 3 for HAZ, 3 for weld metal, 3 for base plate?
This will be my first charpy V procedure.
Any help or comments are always appreciated

 

[metengr]

Yes, for CVN testing you have to either average a test of 3 specimens or if you cannot obtain enough CVN specimens, you can go with one. However, you have only one attempt to meet the minimum value for a single specimen.

Regarding locations, see B31.3, Table 323.2.2, and corresponding text below

(c) A listed material may be used at a temperature
lower than the minimum shown in Table A-1 or
Fig. 323.2.2A (including Notes), unless prohibited in
Table 323.2.2, Table A-1, or elsewhere in the Code, and
provided that the base metal, weld deposits, and HAZ
are qualified as required by the applicable entry in
Column B of Table 323.2.2.

 

[vesselfab]

yes, 3 tests.

what kind of wire are you using?

 

[m3brunof]

I'm using ER80S-D2 and E81T1-Ni1.
So do I need 3 total tests, or 3 tests for HAZ, 3 for weld metal, 3 for base plate?

 

[metengr]

You need 3 specimens for each location - weld metal, HAZ and BM (so 9 total) for an average value. If you do not have enough material for averaging, you can rely on one CVN test for each location.

 

[Guest102023]

The responses given so far are correct, but using two processes does complicate matters. Each process needs to be tested, preferably in isolation, but when there is a minimal amount of GTAW (as in qualification on pipe coupons), you can only capture a mixture of two processes at the root.

 

[m3brunof]

If I qualify two processes together on plate, GMAW for root and FCAW for filler, will two test plates be enough for Tensile Test, Bend Test and Toughness Test?

Thanks for any help

 

[weldtek]

m3,
Contact your lab, give them the thickness of the test plate and tell them your intentions. They'll be able to provide some guidance on test plate length required to yield all of the specimens.

 

[Duwe6]

If you do side bends -- 3/8" and up -- a 12" plate will provide all the necessary specimines. If doing Root & Face bends, add 6-inches.