ASME Standard for Full threaded stud bolt used with Flange Joints

[svi]

The thread292-404005 says that depending on whether some free threads are to be left, either of B18.2.1 or B18.31.2 may be used.

The listed standards in ASME B31.3 and B16.5 for stud bolts and nuts are B18.2.1 and B18.2.2.

The descriptions of the B18.2.1 is,
Square, Hex, Heavy Hex, and Askew Head Bolts and Hex, Heavy Hex, Hex Flange, Lobed Head, and Lag Screws (Inch Series)
Appears that it covers only machine bolts.

and for B18.31.2,
Continuous Thread Stud, Double-End Stud, and Flange Bolting Stud (Stud Bolt) (Inch Series)
What is this standard and has not seen referenced where it should have been.

Cannot see the logic of what it says in the above thread.

 

[svi]

The understanding per B31.3 2016 is that the threads for the full depth of the nuts are to engage. This is a change from the earlier revision of the code. This would mean that at least 1 pitch extension should be included in the stud length.

 

[BJI]

Not sure exactly what your question is but ASME B16.5 nominates the stud length for standard pipe flanges. Considering the required take-up during assembly you will end up with more than one thread pitch extending out the ends of the nuts. B18.31.2 is in the list of references in B18.2.1.

 

[svi]

An informal reply was received from B31 committee admin that the B18.31.2 will be referenced in the next updates.