Right Allowable Table for Flange Leakage 1

[johanybr]

Hi guys
I need a guide respect choose the right properties to input for a Flange Leakage analysis using ASME SEC VIII program included in Caesar II (Piping Stress analysis). My doubt is because I have a Flange A182, F11, CL2, and according to database of the same program for ambient temperature the allowable stress is 20.000 PSI, this correspond to values given on table 1A of ASME SEC II, Part D. However, for this material of flange, in table A-1 of ASME B31.3 and in table 2A of ASME SEC II, part D the allowable for ambient T. is 23.300 PSI, Which value is right?, 20 Ksi or 23.3 Ksi ?.

Thanks in advance

 

[TGS4]

Exactly what calculation is being performed and how is the allowable stress used in these calculations?

 

[johanybr]

Flange Leakage calculation for flanges on a pipe. This question no depend on diameter neither operational conditions (Temperature or pressure), is about materials and right guideline to follow.

 

[TGS4]

johanybr - humour me. EXACTLY what calculation is being performed? Meaning, please present the formula to me. Pretend for a moment that I know absolutely nothing about this flange leakage calculation of which you write. Present the equation(s) and explain it to me.

(Note that there are a whole set of different types of so-called flange leakage calculations. I am familiar with pretty much all of them. I need to know which one you are using so that I can provide assistance to you on your specific equation.)

 

[johanybr]

Oh Thanks dear TGS4
I'm dealing with a Welding Neck Flange, 12”, Thickness of pipe and flange of Sch 120 (25,4 mm), of material A182 F11 CL2 , T(Design)= 305ºC, Pdes= 117 Bar, Axial force= 19.652 N and Bending Moment of 29.234 N.m. The gasket are Metal groove with Outer diameter = 375 mm and Inner diameter = 315mm, thk= 5mm, and M=2 and y= 172 bar according with vendor.
Thanks in advance

 

[TGS4]

Ok. And which "flange leakage" calculation are you using?

 

[XL83NL]

This worries me