Does the total height of the RJ flanges in HG20592 include the raised face?
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For other flange thickness values C specified in HG20592, for RJ sealing surfaces, the height of the raised rim is not included; for other sealing surfaces, it is included. However, the schematic diagram of the total flange height H seems to indicate that the height of the raised rim is included. In contrast, for HG20615, the flange thickness C clearly does not include the height of the raised rim at all. So, the question is: for RJ flanges defined in HG20592, does the total flange height H include the height of the raised rim?
I’ve consulted others; the RJ sealing surface H should not include any bosses
In the HG standard, the RJ sealing surface bosses in both series are not included in the flange thickness. It seems that the regulations vary regarding whether the protrusions of the other sealing surfaces are included in the flange thickness in these two series; I see it stated this way in 3.2.5. In the ASME flange standards, neither raised face nor grooved face is included ； In EN, it seems that they’re all included in the legend; this isn’t used very often, so I’m not sure. It is recommended to first determine which series of standards to adopt, and then refer to the corresponding legends and tables.
Regardless of the standard, the thickness of the flange does not include the height of the protrusion. Our standards are rather chaotic; strictly speaking, the height of the protrusion is not taken into account； According to the principles of strength calculation, the strength of a flange is related to the thickness of the flange ring; it has nothing to do with the protrusion ；