I am working on a piping project and I need to find a table showing dimensions ,class and rating for flanges SA-105& SA-105N. In which code & section I can find these informations?
If you are looking for the difference between SA-105N and SA-105 when talking about the "N" that can be found in ASME Section II Part A.
The ratings for the flanges can be found in ASME B16.5. Be sure that you reference the appropriate year of B16.5 as there have been some subtle changes recently.