The temperature-pressure ratings of the flanges and valves in the CLASS series are the same. Why are PN’s different?
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The temperature-pressure ratings of the flanges and valves in the CLASS series are the same. Why is the PN different? At the same temperature, the pressure value of the valve is lower than that of the flange.
When looking up the pressure corresponding to a temperature-pressure rating, it is necessary to determine the temperature, pressure, and material first, and then consult the relevant standards to find the appropriate pressure. I’m not sure what the standards are for the flanges and valves under the PN you’re checking
Where did you find that \"PN valves have lower pressure than flanges\"?
Comparison of materials under GB/T 12224-2015, HG/T20592, HG/20615, and GB/T9124
Teacher, were you able to find out the reason for the low temperature and pressure values of the PN valve later on?
I checked for 20# steel, PN16, at 50°C, under HG standard IC4 material group; the maximum allowable operating pressure is 14.4 bar； In GB12224, 20# steel belongs to group 2E0; according to table 2-53A, the maximum working pressure is 1.56 Mpa. The two standard methods of material grouping differ, and the problem might lie here.
The temperature and pressure values for the materials in group 2E0 should be referred to in GB/T 9124.1-2019 (see Note 1 in Table 1B on page 34 of GB12224-2015)