Dished Only Head covered by code?

Does ASME Sec. VIII Div. 1 discuss dished only heads? I.E. torispherical head with no inner crown radius equal.

 

[SnTMan]

wlong, I don't know of anything other than UG-35.1 and Appendix 1-6

Regards,

Mike

 

[Duwe6]

No. Your sharp-edged disk would have to calculate like a square corner. Thickness would be HUGE.

 

Ok thanks. I had reviewed UG-35.1 and Appendix 1-6 but in my case, I do not have a bolted flange. The dished only head is simply welded to the shell of the vessel (I'm doing rerate calcs on a 1963 vessel).

 

[Duwe6]

Try Finite Element Analysis, assuming A283 Gr. C material.

 

[SnTMan]

Poor detail, but I guess you're stuck with it

If you are re-rating, you will need to do more than assume a material, you'll need to confirm it.

Regards,

Mike

 

I probably should clarify my statement about rerating. I'm not actually rerating (rerate as in puting a new rating on the vessel nameplate). I've been tasked with calculating MAWP for some of our older vessels with missing information (vessels that we have no U1, data package, calculations, etc.) for internal records.

SnTMan, I actually have orginal dimensional drawings of the vessel that specify material. So, in my case, confirming material is not necessary. However, I do agree with you that I would normally have to confirm the material.

Duwe6, I believe I'm going to give FEA a try.

Thanks for the input all of you.

 

[SnTMan]

wlong, well, yeah I would call original drawings confirmation

Good luck.