Backing Flanges

[pdiculous963]

Does anyone know of a reference material regarding design of backing flanges? I have been unable to find guidance on the subject. I know ASME Appendix 2 allows the use of multiple split backing flanges, but could not find anything on solid backing flanges.

The situation I am in is that I have a flange calculation that shows a required thickness of 2.93" for a non-standard LJ flange. The flange the vendor planned to use is 2". Would a 1" thick backing ring of equivalent material effectively reduce the stress to an allowable level?

 

[SnTMan]

pdiculous963, see Appendix 2, Fig. 2-4 (1) for dimensions, etc associated with loose flanges. Design of the same is straightforward. You might check your vendor's work.

If I understand your proposed construction, two rings stacked, this is not specifically addressed by Appendix 2. Therefore this design is covered by U-2(g), so either you get your vendor to comply with Appendix 2, or you prove your design.

Regards,

Mike