What do pipeline specifications 304/304L and 316/316L mean?
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I’ve come across some tables specifying the models and types of pipes. For example: 1. PIPE SCH 10S SMLS 304/304L SS A312; 2. PIPE SCH 40S SMLS 316/316L SS A312. I can understand all the other specifications, but I’m not sure what the notation 304/304L means – is it referring to 304 or 304L?
This post was last edited by Dipel NDIV on 2017-1-12 at 15:03: PIPE: Pipe; SCH: Wall thickness; EFW: Electrofusion welding; Stainless steel of 304 or 304L grade
304/304L are two grades of stainless steel; the mechanical properties are required to meet those of 304, while the chemical composition must meet that of 304L. It simultaneously meets high corrosion resistance and high allowable stress. It is equivalent to integrating the advantages of two materials. The same applies to 316/316L.
Two grades. . . Both chemistry and mechanics satisfy these 2 conditions. . .
Are the mechanical properties of 304 and 316 the same?
The tensile strength and yield strength are more or less the same, but the allowable stress varies at different temperatures
I couldn’t find the standard for mechanical properties. There are tubing pipes in the warehouse; the material is specified as 316, but the test report indicates 304, so I don’t dare to use them under pressure.
Mechanical properties include many attributes, such as yield strength, tensile strength, bending resistance, and impact toughness. The yield strength, tensile strength, allowable stress, etc. that I’m referring to are specified in GB 50316, ASME B31.3, and GB 20801. Tubing is generally used in instruments, right? We deal with pipes, so we don’t use it very often
The mechanical properties are required to meet those of 304, and the chemical composition is required to meet that of 304L
The mechanical properties are roughly the same: 304 has a tensile strength of 75 and a yield strength of 30, while 316 also has a tensile strength of 75 and a yield strength of 30. .