In cold forming what are 6 or 8 different ways to make a bolt on a Bolt maker?

Standard operations for making standard bolts:

(3 DIE BOLTMAKER)
a. Single extrusion method
A – Single extrusion wire diameter
1 – thread to head bolts
a) Extrude pitch diameter and cone
b) Upset head
c) Trim
B – Body size wire diameter
1 – thread to head bolts
a) Extrude pitch diameter and cone
b) Upset head
c) Trim
2 – long bolts
a) Cone
b) Extrude pitch diameter and upset head
c) Trim
b. Double extrusion method
A – Double extrusion wire diameter
1 – long bolts
a) Extrude body diameter and cone
b) Extrude pitch diameter and upset head
c) Trim

(4 DIE BOLTMAKER)
c. Single extrusion method
A – Single extrusion wire diameter
1 – thread to head bolts
a) Extrude pitch diameter
b) Cone
c) Upset head
d) Trim
B – Body size wire diameter
1 – Thread to head bolts
a) Extrude pitch diameter
b) Cone
c) Upset head
d) Trim
2 – Long bolts
a) Cone
b) Upset head
c) Extrude pitch diameter
d) Trim

d. Double extrusion method
A – Double extrusion wire diameter
1 – Thread to head bolts
a) Extrude body diameter
b) Extrude pitch diameter and cone
c) Upset head
d) Trim
2 – long bolts
a) Extrude body diameter and cone
b) Upset head
c) Extrude pitch diameter
d) Trim

At what point do you change from an open type forward extrusion to the forced extrusion method?

Approx. 30% to 35% reduction-in-area

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