Q: What is the Chinese grade equivalent to the ASTM A213 T22 alloy steel pipe?
A: The equivalent Chinese grade is 12Cr2MoG per GB5310-6.
Q: What are the key characteristics and applications of 12Cr2MoG (T22) pipe?
A: It is a 2.25Cr-1Mo chromium-molybdenum ferritic steel with good high-temperature strength, oxidation resistance, and weldability. It's used for superheater and reheater tubes and steam pipes with wall temperatures ≤580°C in power plants-6.
Q: How does 12Cr1MoVG steel perform compared to 12Cr2MoG (T22)?
A: 12Cr1MoVG generally has slightly higher strength but slightly lower oxidation resistance than 12Cr2MoG-6.
Q: What is T24 steel, and how does it differ from T22?
A: T24 (7CrMoVTiB10-10) is an enhanced grade derived from T22. With additions of vanadium, titanium, nitrogen, and boron, it offers higher creep strength at around 550°C and, notably, can be welded without preheat or post-weld heat treatment for thin-walled sections, making it attractive for boiler water wall panels-6.
Q: Which alloy steel grades are commonly used in petrochemical cracking units per GB 9948?
A: Grades include 12CrMo, 15CrMo, 1Cr2Mo, and 1Cr5Mo-1.
