Ring Joint Flanges for 38 inch and larger size as per ASME B16.47 Series A

[Shahpar]

Refer to ASME B16.47 Table 29 note (b): Ring-Joint gaskets are not contemplated for NPS 38 and larger flanges. However, Ring Joint flange dimensions fare available in table-35C for NPS 48. My question is that how Ring-Joint Gasket for NPS 42 are designed. Do we need to refer ASME SEC VIII D1 appendix 2 for 42 inch size while all dimensions other than gasket grooves are available in mentioned table.
Also, is this considered special design flange or ASME B16.47 Series A rated flange if ring joint gaskets are contemplated by flange manufacturer. I want expert opinion in this issue. I will appreciate if some references or case study will be shared in reply to this thread.

Thanks in advance.

 

[GD2]

That's the direction I would go in absence of any dimensions not found in a standard (example ASME B16.47) acceptable to the construction Code - qualify by Sec VIII Div1 Appendix 2.