A-333 Gr.7 pipe / A-420 WPL3 Welding

[er_scec]

Hi everyone, is it posible or recomendable to weld A-333 Gr.7 pipe with fittings A-420 WPL3/A-350 LF3, the intention is to use A-333 Gr7 instead of A-333 Gr.3 (only pipe). As in the project there are way more pipe than fittings and for the operating temperature A-333 Gr.7 is enough, but the problem is that there are no equivalent fittings for A-333-Gr.7, so I want to use A-333- Gr3 compatible fittings with A-333.Gr7 pipe.
One material es P-number 9A and the other is 9B, it might be some problems to weld these materials?, or preparing a good WPS will be enough?

Thanks for you suggestions

[pg1916]

Hello,

The welding issue is between P9A(2.5% Ni steel) to P9B(3.5% Ni steel). . These steels are perfectly welddable to each other,using the consumable of 3.5% Ni steel, SMAW -E-8016/8018-C2 and GTAW-ER-80S-Ni3.

What's the design temperature? Minus -75deg C or minus(-) 101 deg C??

If you could send me the details concerning this in my personal email, I would be able to guide you towards the solution.

Thanks.

Pradip Goswami,P.Eng.IWE
Welding & Metallurgical Specialist & Consultant
Ontario,Canada.
Email-pgoswami@sympatico.ca,
pgoswami@quickclic.net