Thread Pitch Standards

[gfthelen]

Hi,
It has been a long time since I have been to Eng-Tips, hope you can help.
Is there ANY Standard, ASME, ASTM, SAE etc. that recommends the type of thread to use for certain fastening situations?

When to use coarse thread vs. When to use Fine Threads?

Other than 'Rule of Thumb" is what I am looking for

Thanks for your help.
Greg

 

[csk62]

Regarding UNC vs UNF, see link below. In my work experience 99.5% of the time, coarse threads are used.

https://itafasteners.com/a-handy-guide-to-types-of-fastener-threads.php

 

[MGZmechanical]

For flanges bolts over 1" it's recommended to be 8 tpi. In metric bolts for flanges over M36 fine pitch it's recommended.


For hydraulic cylinder stems also fine pitch it's used (at least in metric).


Regards,