Pressure Vessel with W stamped on Nameplate

[IrwinL]

Hello,

I ran into a pressure vessel that was designed / fabricated to Section VIII, Div. 1 and registered with local jurisdiction authority. In addition to normal markings (e.g. RT-1), the nameplate has a "W" marked. What does the "W" mean? I tried checking section viii the marking section (and Google..) but can't seem to find anything on this. Also the nameplate doesn't have a "U" marking.

Thanks in advance.
Irwin

 

[david339933]

W is welded construction. It has been removed from the Code. It should have a U under the ASME Stamp though.

 

[IrwinL]

Thanks for the info David. Just checked the version of the code at the time and it specifies the W marking meaning.