Welded Nozzles to Flat Heads

[John21423]

Hi All,

I have a cylindrical shell vessels that is capped by two welded on flat plates. I want to connect a small nozzle (NPS 2) to the center of the flat plate.
Following ASME Sec VIII Div 1, would I be allowed to use UW-16 for this connection, or would I have to use UW-13?

UW-13 is for pressure parts attached to flat plates to form a corner joint, which seems like it would apply, but the rules seem more geared towards how flat plates are attached to main shells, rather than nozzles attached to flat plates.

UW-16 is for nozzles connected to shells, heads, etc., but doesn't specifically state flat heads. UW-16 also states the connection should be a category D weld, which is defined in UW-3(d) as joints connecting nozzles to shells, heads, or flat sided vessels (again, not stating flat heads), while category C is for flat heads to main shell, nozzles, etc. (again, seeming more like flat head to nozzle, rather than nozzle to flat head. not sure if there is a difference).

Thanks in advance

 

[SnTMan]

John21423, a flat head is a head. Nozzle to head seam is Cat D, weld detail is per UW-16.

Reinforcement (if needed) is per UG-36, UG-37, UG-39, etc.

Regards,

Mike

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

 

[John21423]

Thanks Mike, That's what I was leaning towards.

So UG-13 is more for flat heads welded main shells that form a corner joint close to the edge of the flat plate?

Regards,
John

 

[SnTMan]

Well, UW-13 rules are a little more broad than that, but yes they are intended for main vessel components rather than openings in the same.

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