In the infeed process, the profile grooves
of the rolls have the pitch of the thread to
be produced. The rolls, driven at the same
speed, move in the same direction. During
rolling, the workpiece moves due to
friction with no axial shifting. As the
thread produced by this means is an exact
copy of the rolling dies, threads of this
kind have a very high pitch accuracy. The
maximum length of the thread is limited
by the width of the rollers (30-200 mm).