nominal bolt diameter in flange leakage/stress module

hello,
I need some explanations about value to be used in the "bolting information"->"bolt diameter" of the flange/leakage/stress calculation module of CaesarII.

It is clear from the help on line of the software that the nominal diameter of the bolts shall be used.
Reading into ASME VIII div1 app2, the "Ab" is "the cross-sectional area of the bolts using the root diameter of the thread or least diameter of unthreaded position, if less"
The root diameter, I think, is the core stressed diameter of the bolt (the minimum diameter in a bolt)

BUT ... WHY CAESARII ASK FOR THE NOMINAL AND NOT THE CORE OF THE THREAD?
How can the software evaluate the core from the nominal?

Please note that I have used "succesfully" the CaesarII ASME VIII module in the past years, each time with the nominal imperial diameter of the bolts converted in mm because I work to SI units files (for example 1" --> 25.4mm). I check that the CTRL-F routine automatically does the same.
Now i have to check an ASME B16.5 flange with metric bolts and I want to follow the same method (for a metric M24 bolt can I input 24mm in the "bolt diameter").

The bolt area is a lookup (table) based on nominal diameter.

Is it possible to share this table?

If the user inserts a no standard value respect to the table (for example 24mm instead of 25.4mm/1") , which is the behaviour?
(perhaps the software chooses the nearest rounding down, in this example 7/8"?)

Please file an SR on Smart Support for this.

thank you Richard.

SR sent with some simple improvement suggestions.

pointed out that, despite my insertion on SR smart support (no reply by nobody), the calculation remains not correct also in CII 2019 SP1.
for example, if you insert 19.5, 20mm in the bolt diameter, the value used by the software is always 19.05mm corrensponding to 3/4" bolt... (the result remains not changed)

I presume that the software does not use the inserted value, but a table of standard diameters of bolts in US dimentions...

Lido,

I show your Service request filed originally in February was attached to a Development item with your request. Were you never informed by the analyst that this is what happened? I have your email address in our system. I will reach out to you so, you may respond directly to me.

for all collegues involved in ASME VIII div.1 app.2 flange verifications with CaesarII tool, I see that no solution has been applied in last revision 2019 of the software... therefore I can no stop to kindly ask Intergraph to put a patch on this simple but important BUG of the software.

collegues, please uphold my little request!