HEIDENHAIN iTNC 530 (340 49x-02) - Manual (Page 271)

HEIDENHAIN iTNC 530 271
7.
4 Miscellaneous F
unctions f
o
r Cont
our
ing Beha
vior
Feed rate in millimeters per spindle revolution:
M136
Standard behavior
The TNC moves the tool at the programmed feed rate F in mm/min.
Behavior with M136
With M136, the TNC does not move the tool in mm/min, but rather at
the programmed feed rate F in millimeters per spindle revolution. If
you change the spindle speed by using the spindle override, the TNC
changes the feed rate accordingly.
Effect
M136 becomes effective at the start of block.
You can cancel M136 by programming M137.
Feed rate for circular arcs: M109/M110/M111
Standard behavior
The TNC applies the programmed feed rate to the path of the tool
center.
Behavior at circular arcs with M109
The TNC adjusts the feed rate for circular arcs at inside and outside
contours so that the feed rate at the tool cutting edge remains
constant.
Behavior at circular arcs with M110
The TNC keeps the feed rate constant for circular arcs at inside
contours only. At outside contours, the feed rate is not adjusted.
Effect
M109 and M110 become effective at the start of block.
To cancel M109 and M110, enter M111.
In inch-programs, M136 is not permitted in combination
with the new alternate feed rate FU.
M110 is also effective for the inside machining of circular
arcs using contour cycles. If you define M109 or M110
before calling a machining cycle, the adjusted feed rate is
also effective for circular arcs within machining cycles. The
initial state is restored after finishing or aborting a
machining cycle.