Complicated Swing Hatch (Flat Head) Design - ASME VIII, Div 1, Custom Flange

[Doodler3D]

ASME Stalwarts,

I'm working on a pressure vessel with a hatch that also functions as an unstayed flat top head. Based on my reading here, I get a hint that one has to work with the mandatory appendix - 2 and treat this as a loose ring flange. However, there is metal to metal contact with a central plate sandwiched between the flat head and the flange, which possibly leads to Appendix Y. Any advise on this one? Should I treat the flat head and central plate support as one?

Thank you.

SS304L Construction, 100 psi design pressure.

 

[SnTMan]

DoodlerDaru, ignoring the "central plate" (what's that for?) I'd say Apx Y, Class 3, Cat 3 applies.

Swing bolts? See Apx 2, definition of "A". Don't know if Apx Y has provisions for this or not.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[Doodler3D]

Thanks Mike, the central plate (same ID/OD as the flat head) supports swappable guide vanes for a paddle mixer. I have to throw the kitchen sink at this one since the original design/calculations followed BS 13445-3 (lost/missing) and now needs ASME VIII calcs. Looks like ASME VIII, App. Y seems to be correct, as you suggested.

 

[XL83NL]

You probably meant (BS) EN 13445-3, correct?

Huub
- You never get what you expect, you only get what you inspect.

 

[u236]

Hi, you can use the Appendix Y to verify the flange in Gasket seating condition, but the flange should be verified in Appendix 2 for the operating condition

 

[Doodler3D]

@XL83NL yes, BS EN* 13445

@u236 If Appendix Y assumes metal to metal contact, the gasket would not generate any moments. I'm a bit confuseD when you say ' Appendix 2 for operating conditions'.

 

[SnTMan]

u236, I think you are mistaken. Appendix Y anticipates negligible gasket seating loads, therefore the design necessarily considers operating conditions. See Y-1(b). See Y-1(c) for why Appendix 2 is not suitable for this type of flange.

The problem with sloppy work is that the supply FAR EXCEEDS the demand