Questions about the material grade table?
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In the material grade standards, there are two different ways of describing valves: 1, 2, Question A. Are both of these representations acceptable? When is the first method suitable, and when should the second one be used? For Question B, valve 1 generally corresponds to the flange standard SH3406, while valve 2 corresponds to the flange standard HG20592B. My question is that the end configuration of a valve only indicates the pressure rating and whether it has an RF surface; it does not indicate the flange standard that can be used with it. Can valve 1 (which follows API standards) be paired with HG20592B or 20592A as well?
This post was last edited by ice2008 on 2024-7-16 at 10:35. Question B: Once the pressure rating PN or class of a valve is determined, does that mean the flange type is also determined? Do valves with PN rating use flanges with PN rating, and do valves with class rating use flanges with class rating? The difference between 20592 A and B is the size of the pipe fittings; the flange surfaces are the same, and both belong to the PN series.
A: The first type is US-standard material, and the second type is Chinese-standard material. B: Different flange standards depend on the outer diameter series of the pipeline; for outer diameter class Ⅰb, SH standard flanges are used, for class Ⅰa, HG standard Type A flanges are used, and for Class II outer diameters, HG standard Type B flanges are used.