[MW:21669] Notch Toughness Properties of WPQR.

Dear Experts,

Greetings of the day.

I came to an issue in WPQR of P No. 1 Group 2 Base metal in CVN Impact testing of weld and haz. Design Code is ASME Sec. VIII Div. 1 Ed. 2013 & ASME Sec. IX Ed. 2013.

Base Metal Thk. 25 mm. SA 516 Gr. 70

PWHT: Normalizing at 920+/-10º C.

Holding Period 65 Minutes.

Welding Process SMAW (Manual)

Electrode Used: 3.15 & 4.0 mm. E7018-1 (Impact tested in as welded condition).

Position: 3 G Uphill (Stringer/ Weave Bead)

CVN Impact test results of HAZ: 

Test Temp. -57º C (Temp. reduction applicable)

Specimen size: 10 x 5 x 55 mm.

Values in Joules HAZ Top Side- 5, 19.5, 4 (Average 9.50)

Values in Joules HAZ Bottom Side- 4.5, 4, 17.5 (Average 8.67)

Values reqd. for sub size specimen: Individual min. 8 J & Min. Average 10 J.

CVN Impact test results of Weld:

Test Temp. -46º C (Temp. reduction applicable)

Specimen size: 10 x 10 x 55 mm.

Values in Joules - 9, 14.5, 8.5 (Average 10.67)

Values reqd. for Std. size specimen: Individual min. 16 J & Min. Average 20 J.

What shall be the reason of failure? Is electrode selection OK?

Awaiting for your prompt favorable response at the earliest.

Thanks & regards,

C. R. GANDHI