SA213T11 is a Seamless ferritic low alloy steel boiler tube used in super heater elements, and heat exchangers (P Number 4 ). This 1 Cr-0.5 Mo alloy is suitable for use in pressure-bearing plants at temperatures up to 538°C.
Grade 310S is a low carbon version of grade 310. Grade 310 is a medium carbon austenitic stainless steel, for high-temperature applications such as furnace parts and heat treatment equipment (P Number 8)
AWS 5.9 ER 309/309LMo, Alloy ER 309LMo is used for the welding of dissimilar materials between stainless and low alloy steels, as well as for overlay cladding. This alloy is well suited for austenitic-ferritic joints with a maximum application temperature of 300°C.
Looking to your application involving a design temperature of 450 °C, I would advise you should use ENiCrFe-2 ( AWS A5.11 SMAW Filler) / (AWS A5.14 ERNiCr-3 – Nickel Alloy 82 ), GTAW/GMAW filler with 100% Argon gas as shielding and backing for pipe welding, it can be used from cryogenic temperature to 815 °C.
Alternatively, you can also use ERNirMo-3 (Alloy 625) AWS A5.11. it can also be used up to 982° C. As per the Filler metal consumable product data online sheet.
The benefit of using nickel alloy base consumable, it has a thermal expansion coefficient intermediate between that of austenitic stainless steels and low-alloy steels, thus, nickel-chromium–iron Alloys 82, 182, 132, 52, and 152 have been used for dissimilar metal weld joints to minimize the residual stress and strain in the weld joints.
Particularly in your application, you are dealing with the joining of Tube material, so, distortion can be foreseen as an issue if not taken care of.
Secondly, for SA 213 Grade T11, (1 Cr-0.5Mo alloy), you may need preheat-post heat according to your code of construction/section thickness requirement.
As per ASME VII Div.1 250 ° F / 121 ° C) OR as per ASME B31.3 (250 ° F / 120 ° C), Approximately.
While, PWHT as per ASME VII Div.1 (1100 – 1200 ° F / 593 – 650 ° C) OR As per ASME B31.3 (1200-1300 ° F / 650° C – 705 ° C)
Here, Your application involves also the use of Stainless Steel, Generally, the PWHT range falls within the range of Sensitization Temperature range (500 – 850 ° C) But for the material you have chosen SS 310S, Fortunately, this PWHT temperature is not a matter of worry because this 25% chromium and 20% nickel alloy is designed to provide high resistance to oxidation and corrosion.
The fact is that Grade 310S is a lower carbon version, than 310 , less prone to embrittlement and sensitization in service.
This is my opinion only. By the way, the welding procedure qualification tests are highly recommended.
You are also advised to refer to the latest applicable code of construction and standards for clarity of the Preheat-PWHT range.
I Hope, this advice might be useful to you.
References:-
https://www.sciencedirect.com/topics/materials-science/nickel-alloys
https://nickelinstitute.org/about-nickel/nickel-alloys/
We hope this information is useful to you!
Welding Consultant,
Weld Met Advisory Services
