Flat die method (Figure 6.1)

Figure 6.1: Layout for flat-die thread rolling 1 fixed die, 2 moving die, 3 conductor bar, 4 pusher

The thread is produced by two flat dies which have the profile of the thread to be produced. The profile grooves are inclined by the pitch angle of the thread to be produced. One flat die is fixed and the other is moved backwards and forwards by a crank mechanism. The blank to be rolled is carried along by friction.

Segment (planetary type) method (Figure 6.2)

Figure 6.2: Layout for thread rolling with segments. 1 conductor bar, 2 segment, 3 rotating roll, 4 locking slide, 5 pusher

Here, instead of a straight rolling die, curved segments are used; their length is the circumference of the blank to be rolled. The counterpart to the segments (there may be several in a row around it) is a rotating rotary die. On one revolution of this die, the number of segments arranged around it equals the number of workpieces rolled.

Infeed process (Figure 6.3)

Figure 6.3: Arrangement of the workpiece and the tools during infeed process,a) workpiece, b) dies, b ₁ fixed, b ₂ adjustable die, c) work rest

In...