Naming of metal materials
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During a recent technical exchange, I have a question regarding valve materials and would like to ask the experts for their advice. For example, with material 316, what does the number here mean and what does it represent? Are there any relevant specifications or instructions?
This post was last edited by c3h5e8n1 on 2020-12-21 at 14:53. Sorry, I don’t have it available at the moment. Since this post of yours is so quiet, I’ll probably explain it to you, though not in full. Among the common metal materials used for valves, the valve body is usually carbon steel: CS, WCB ； Stainless steel: 304, 316, 316L. Both CS and WCB are carbon steels, and there is not much difference between them. However, it is important to use low-temperature carbon steel in low-temperature environments. As for stainless steels, 304, 316, and 316L have progressively better corrosion resistance, among other properties. Stainless steels also exhibit good resistance to low temperatures, so temperature is generally not a concern. But it should be noted that stainless steels cannot resist corrosion caused by Cl- ions. I’ve also heard that there are urea-grade 316 grades with even greater corrosion resistance, designed for use in urea-based media. Additionally, when selecting a material, considerations such as wear resistance and cavitation resistance must also be taken into account; coatings or other solutions can be applied if necessary. As mentioned above, I am not very familiar with the selection of valve materials; please forgive my ignorance.
To truly understand the relationship between specific material grades and their compositions, etc., one must refer to the relevant material standards.
316 is the material code according to American standards; by referring to the relevant specifications, one can find out the exact contents of various components
316 is a material, a type of stainless steel
It’s just a grade code; the table on the 3rd floor is the correct one……
In other words, the numbers here don’t have any specific meaning, nor do they represent any particular attribute
Refer to GB/T12224-2015 General Requirements for Steel Valves; the material requirements for pressure-bearing components are provided after page P27. Generally, for the valve body, one looks at the casting, and so on.