Flange Design per ASME BPV VIII Div 2 Part 5

[kuanon]

When I design flange and bolts with ASME BPV VIII-2 Part 5 rules, what stress table should be used for bolt material? Use Section II Part D Table 3 or 4?

For design pressure, Part5 paragraph 5.7.1 requires that flange should be designed per 4.16. Per 4.16, stress table 3 should be used. But for servce stress, Part 5 paragraph 5.7.2 uses Table 4 stresses.
It is pretty confusing, could anybody please give me a help on this?

Thanks

 

[TGS4]

It depends. Are you using the allowable stress basis for design or for checking actual operating conditions? You do understand that in ASME flange design, the design allowable stresses for bolts have absolutely no correlation to the actual in-service operating stresses, right?

 

[kuanon]

Hi TGS4, Thanks a lot for your reply. What confusing me is the allowable stress for design, not for service. In VIII-2 , part5, 5.7.1, flange and bolt should be evaluated per 4.16. Do I only use 4.16 formulas and use Tabel 4 allowable stressees or need to use Table 3 stresses?

Thanks
Kuan

 

[TGS4]

Follow the rules, as written, in 4.16.

 

[kuanon]

4.16 uses Table3. But a note in Table4 title indicates that Table4 can be used for part 5 5.7.1 and 5.72. That is why I am confused.

Another question. 4.16 is Appendix2 flanges. Do you know where Appendix Y flanges is covered in VIII-2?

Thanks