Can PG-29 dished heads be used in B31.1 Power Piping?

Dear All,

Problem is that I am designing & stress analyzing a 3000 mm dia pipe with 20 mm thick for a steam header as per B31.1 and would also like to model in caesar II.

For end caps / closures I cannot use a flat unstayed plate because thickness in excess of 120 mm comes in calculation. Can I use PG-29 dished heads as per ASME BOILER Sec I code? Are they prohibited or not ? if they are not prohibited how can I model in caesar.

Prompt replies will highly be appreciated.

Regards,
Salz

Caesar uses beam elements so cannot deal with a cap directly. An end cap would need a separate calc to an appropriate code. ASME VIII div 2 would probably be ok, or whatever code your vessels are designed to. Just model it in Caesar as a weight.

Salz,

Please be careful, you have a D/t=150.

Best regards,

Thanks MoverZ, you are right as I can only model the end caps/dished heads as a weight on end nodes. As per B31.1 - 104.1.1 the closures can either be designed as per Standards listed in 126.1 table OR as per ASME Sec I-PG-31 (unstayed flat head and cover).

My main problem is to design them as per Asme Sec I, PG-29 (Dished Heads) because that I can. ASME B 31.1 doesn't restrict use of PG-29 but also doesn't permit it.

[I know this is not a CODE discussion forum but if anybody have any idea or have worked on similar situation...than I'll be glad to hear an opinion]

@Dan. Yes I need to be careful but do I have a dished head option or not is the main thing!. Thanks for your input anyway.

Regards,
Salz