Ultimatley, I would like to calculated torsion forces viewed by the mandrel on a down coiler. My boss is convinced that material properties effect the forces seen at the madrel. More robust material equates to more torque.
The grades envolved are everything from plain carbon steels, Mn steels, HSLA's, Boron treated, medium carbon, and high carbon. I'm putting together a capabilities chart for our entire product range. But mechanical properties for these steels at the coiling temperature is most relevant since we coil at the coiling temperature and not at room temperature.
I'm starting to think the torque at the mandrel has nothing to do with the material properties at all. It is a statics problem with the torque resulting from the tension in the material placed there by the different rotational speeds from F7 and the coiler mandrel.