Permissible Imperfections in Flange Facing Finish for Raised Face and Large Male and Female Flanges
Permissible Imperfections in Flange Facing Finish for Raised Face and Large Male and Female Flanges
(OP)
B16.5 - 2003 Table 3 Permissible Imperfections in Flange Facing Finish for Raised Face and Large Male and Female Flanges
Greetings!
I would like to ask on how to evaluate the flange face imperfection referring to B16.5 - 2003 Table 3 p.61
Please see the attached document and please let me know if the flange is still accepted or not.
The material is 1/2 Inch, PN10 RF Type A182 F316L
Thank you very much.
Kind Regards,
AweldI
Greetings!
I would like to ask on how to evaluate the flange face imperfection referring to B16.5 - 2003 Table 3 p.61
Please see the attached document and please let me know if the flange is still accepted or not.
The material is 1/2 Inch, PN10 RF Type A182 F316L
Thank you very much.
Kind Regards,
AweldI





RE: Permissible Imperfections in Flange Facing Finish for Raised Face and Large Male and Female Flanges
Second, keep in mind B16.5 acceptance criteria are for new flanges.
I suggest to get a copy of PVP2013-97813. The current acceptance criteria in B16.5 for flange imperfections are, at some parts, unrealistic.
The paper by W. Brown elaborates on how to overcome this problem. He also gives recommendations of what is considered a better acceptance criteria.
Here's what he has to say on this table;
That being said, applying PCC-1 2013 to find out how radial is to be interpreted, I think your 1st measurement is incorrect, the 2nd is correct (that one is actually the radial distance).
For radial imperfections, you have to measure along the path from center to the raised face end, radially.
That what u did in picture 2. In picture 1, you measured some sort of width in stead of depth.
Think of a leakage path, and the potential a flaw has for leakage to be initiated.
The deeper (hence less chance the gasket filler may fill the flaw) and longer (i.e. more radial) the path, the greater the potential for leakage.
RE: Permissible Imperfections in Flange Facing Finish for Raised Face and Large Male and Female Flanges
With regards to ASME B16.5, the imperfection shown in the picture would actually fall on the radial projection (3mm) only and not on the redial projection and depth category (1.5mm), is that correct?