On 20/04/2016 11:01, News wrote:
In message , GB
writes
On 19/04/2016 10:12, Syd Rumpo wrote:

https://www.youtube.com/watch?v=3kxcw08p_oY

Doesn't show the hex head, but it'll just be a different set of dies.

Cheers. I enjoyed that video. Those automatic machines are impressive.

Extremely. Not knowing anything about these processes, I wonder why the
bolts are cold forged, but the nuts require heat.

I would guess that the bolts are cold forged because there are several
stages and it would be difficult to clamp them firmly enough while hot
and keep them hot through the stages.

The nuts are made in a single motion with no need to hold them other
than with the hex forming die. The threads are cut cold. Also, the nuts
don't have to be as strong.

Pure speculation.

Cheers
--
Syd