Why are the specifications for the butt-weld flange with neck DN50 smaller than those for DN40?
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This post was last edited by YeTangZhangShang on 2019-4-4 at 09:33. In HG/T20592, pages 42–43, for PN10 and PN16, the values of flange neck R and flange height H are given. The values for DN50 are smaller than those for DN40. Is this a printing error? PS: The issue on floor 8 has been resolved.
It’s not mentioned in the corrigendum. . . Please help find out if there are printing errors in HG20592-2009. Haichuan Chemicals Forum – https://bbs.hcbbs.com/thread-830843-1-1.html
Flange height changed from 28 to 32, R5 changed to R6
A corrigendum has been issued for this standard, and those who purchased it through official channels have it.
This post was last edited by Baoji ChaoSheng Titanium Industry on 2019-4-3 at 17:52. This is not a printing error. The European standard system in the first half of HG/T20592 is based on the British standard EN1092-1-2002. In EN1092-1-2002, DN40 and DN50 are the dividing points. For nominal pressures ranging from PN10 to PN40, and nominal diameters up to DN40 (including DN40), the flange size of PN40 is used. DN50 PN10 and 16 have the same size. DN50 PN25 and PN40 have the same dimensions.
I don’t know if the original poster will understand with my explanation.
I also looked at that corrigendum. It’s not at all like that. If you insist that there is a problem with this flange size, then you have to overturn EN1092, the standard from which this flange derives. Since this standard has existed for decades without any corrections being made to this obvious error, there must be some rationality in its design; therefore, following this standard is certainly correct.
Understanding it from the dividing point is still speaking of the past.