CVN test at Weld Metal with ER70S-6

[Karik87]

Hi experts,
Could you please share your experience regarding CVN impact testing for ER70S-6 filler metal?
I’m currently qualifying a PQR for A333 Gr.6 to API 5L Gr.X65 using ER70S-6 (GTAW + SMAW).
When conducting the weld metal impact test (full-size specimens) at -46 C degree, I obtained very inconsistent results: 11 J, 120 J, and 80 J.
I repeated the test on another set of CVN specimens, but the same pattern appeared — two high values and one significantly low value.
All three specimens were taken from the same area of the weld on a test coupon (pipe 6" OD, 11 mm thickness).

I’m trying to understand the cause of this variation.
Has anyone encountered this issue before? Any insights or suggestions would be greatly appreciated.

Thanks in advance!

 

[r6155]

There are many errors during specimen extraction, machining, and testing.
Did you witness all the steps?.

 

[EdStainless]

Were the notches ground or broached?
I loathe broached notches.

 

[Karik87]

Were the notches ground or broached?
I loathe broached notches.

@EdStainless All notches were broached and checked the diameter.

 

[Karik87]

There are many errors during specimen extraction, machining, and testing.
Did you witness all the steps?.

No sir, we just witness the testing only.

 

[r6155]

And the impact test at the HAZ?

Was another test performed?

 

[EdStainless]

So you also looked at the face of the notch to assure that there was no tearing or chatter?

 

[Karik87]

So you also looked at the face of the notch to assure that there was no tearing or chatter?

I am sure that no tearing or chatter at the notch.
Yesterday, I changed the CVN test to another test lab.
At the first set, results of absorbed energy are 12J, 43J, 85J.
The second set, results are 53J, 33J, 28J.
The CVN results of ER70S-6 in certficate are 151J, 153J, 147J in 1G position.
It is very difficult for me to explain the test results to Client.

 

[Karik87]

And the impact test at the HAZ?

Was another test performed?

No sir. It is tested at weld metal.
Another test performed at other test lab. Please see my response above.

 

[SJones]

The consumable batch certificate is 3.1 or 2.2 ?

 

[r6155]

@Karik87
You said: "It is very difficult for me to explain the test results to Client."

Well, you need to read more and take a welding and NDT training course
.Impact tes requires a step-by-step inspection by qualified personnel.