HEIDENHAIN SW 54843x-02 DIN Programming - Manual (Page 73)

HEIDENHAIN MANUALplus 620, CNC PILOT 640 73
2.3 Units—Recessing
"Parting" unit
The unit parts the workpiece. If programmed, a chamfer or rounding
arc is machined on the outside diameter. At the end of cycle, the tool
returns to the starting point. You can define a feed rate reduction,
which becomes effective as soon as the position I is reached.
Unit name: G859_CUT_OFF / Cycle: G859 (see page 303)
Access to the technology database:
 Machining operation: Contour recessing
 Affected parameters: F, S, E
Cycle form
X1, Z1
Starting point of contour in X, Z (X: diameter value)
B Chamfer/rounding
 B>0: Radius of rounding
 B<0: Section length of chamfer
XE Inside diameter (pipe)
I Diameter for feed-rate reduction. Limit diameter over
which traverse is at reduced feed rate.
E Reduced feed rate
D Maximum speed
K Retraction distance after parting: Lift off the tool laterally
from the workpiece surface before retraction
SD Speed limitation from diameter I up
U Starting with this diameter the part catcher is activated
(machine-dependent function)
Further forms: see page 56
The limit to the maximum speed "D" is only effective in the
cycle. After the cycle ends, the speed limit before the
cycle becomes effective.