Appendix 2 Flange Tolerance

[lcmechengr]

I am havinig to recommision an old exchanger, part of which I am analyzing the flanges per ASME Section VIII Div 1 Appendix 2. It appears that the body flanges have been fabricated from a slip-on flange which has had the inner portion of the flange thickness stepped done to accept the tube sheet. When this area was was machined the recessed area ended up being very close to the inner edge of the bolt cirle (approximately 1/32 metal between bolt hole and turned down area). Is there anywhere in the code that mentions minimum metal thickness at the edge of a bolt hole? Thanks for any advice.

 

[SnTMan]

lcmechengr, I am not aware of any such requirement. This is more a matter of practice. I would not design such a narrow margin, but there is no harm in it. I am assuming this face is opposite where the nut seats.

Regards,

Mike