For long-neck butt-weld flanges with a pressure of 1.6 MPa, DN=500 is selected; it was found that when M20 nuts are used, they touch the edge of the flange
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For a long-neck butt-weld flange with a pressure of 1.6 MPa, DN=500 is selected; it was found that when using M20 nuts, these nuts touch the edge of the flange. Should I switch to a type A socket weld flange instead?
Which standard flange is being used? Check the standards; if the bolt is matched to the flange, this problem will not occur.
Such problems have indeed occurred; in those cases, drilling was done up to the shoulder of the fitting, but there was no interference with the flange neck. If you have any issues, you can contact QQ2461870026
Yes, it’s because the flange wasn’t processed accurately; the eye moved inward
It shouldn’t be; according to the standards, they shouldn’t touch each other when manufactured.
That can’t be right; according to HG/T20592-2009, the bolt hole diameter of DN500 at 1.6 Mpa is 33 mm, and that’s considered acceptable, so a M20 bolt should be even more suitable.
JB/T4703: After checking, the center value is 600, the thickness of the larger end of the neck is 22, and the maximum diagonal dimension of the M20 nut is around 35 mm. 600 – 35 = 565, which is greater than 500 + 22 + 22 = 544. There’s definitely enough margin.
The current standard is NB/T47023-2012
Is it okay if the outer edge of the flange is 2.5 mm smaller?