Head Attached to Shell

[htman]

Am I required to follow the rules of UW-13.1 if I am welding a hemispherical head directly to an Appendix 2 weld neck flange? (my nominal head thk is less than my flange hub thk)

Thanks

 

[gr2vessels]

The tappered transition is mandatory, not only because of the code rulling, but because of proper engineering principles;- abrupt changes in cross section are high stess concentrators, so use design solutions which allows for smooth transition, the easiest being the tappered transition.
Cheers,
gr2vessels