Bolt marking 2

[metalonis]

I have some SA-193 B7 bolts, some are marked B7 and some are marked J B7. Is there some significance to the "J" marking?

 

[wes616]

J most likely means it is a rolled thread, vs. a cut thread.

Wes C.

 

[ajack1]

Isn't the J a rounded end to the thread?

 

[diamondjim]

ajack is right, it means the
thread a full radius, and needs the
mating part to be slightly truncated
as to not interfere with the radius.

 

[diamondjim]

http://www.uscti.com/TapsFinal2.pdf

url for information on UNJ threads.

 

[wes616]

thanks for setting me straight guys.

Wes C.