Ball valve body joints

[Wintechcad]

Hi,

I am new to this forum - not so new to engineering though.

Are UNF threads acceptable for bolted body joints on ball valves per ASME B16.34? I note that some other standards state that coarse threads be used, but sometimes when running calculations per para 6.4.2 (a), just going to fine threads can prevent having to go to the next bolt size.

Thanks in advance

 

[gerhardl]

A rose is a rose is a rose!..

What does the standard and attachments actually say?

I suspect that if the one is especially mentioned in the standard and the other not, the latter is an exception and as such a deviation that could raise questions about validity, and you would probably not want that!

The only ones properly able to answer your question are the issuers of the standard.

 

[bcd]

As your citing the specific paragraph in B16.34, you know it only require that bolting comply with B1.1 or B1.13. It does not specifically mention thread series, so you are free to use anything listed in the B1.1 or B1.13 and still claim conformance to B16.34. However, good Engineering practice should be used.