Seeking help: What is the difference between valve materials Q345D and Q235B?
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Seeking help: What is the difference between valve materials Q345D and Q235B?
The valve body of a valve must not be made of sheet metal; it can only be made from forged or cast materials. Your question itself is incorrect – some smelting plants use valve bodies made of sheet metal, as do those factories that cut corners in production
I’m not referring to the valves, but rather the material of the expansion joints. Sorry
The chemical composition is different, the mechanical properties are different, the minimum operating temperature is different, and the minimum impact temperature is different.
The former low-alloy steel has a yield strength of ≥345 MPa, while the latter ordinary steel has a yield strength of ≥235 MPa; their impact energy is also different.
This answer is very professional; these days, Q345B is rarely used for expansion joints – Q235B is used in its place