Siemens SINUMERIK 840D Programming Manual page 298

4
Turning Cycles
4.5 Stock removal cycle – CYCLE95
DT and DAM (dwell time and path length)
With these two parameters you can program an
interruption in the individual roughing cuts after a
defined path for the purposes of chip breaking.
These parameters only apply to roughing. In
parameter DAM you define the maximum path after
which chip breaking is to be performed. In DT you
can also program a dwell time to be included at each
of the interruption points. If no path has been
specified for cut interruption (DAM = 0), then
uninterrupted roughing cuts without dwell times are
generated.
_VRT (lift)
With SW 4.4. and higher, the amount by which the
tool is lifted off the contour in both axes during
roughing operations can be programmed in
parameter _VRT.
If _VRT=0 (parameter not programmed), liftoff is 1mm.
The retraction distance is always measured in inches or
metric depending on the programmed system, i.e.
_VRT=1 for inch àprogramming produces a tool retract
of 1 inch.
Further notes
Contour definition
The contour is programmed in a subroutine whose
name is defined as a parameter.
The contour subroutine must contain at least three
blocks with movements in both axes of the machining
plane.
The machining plane (G17, G18, G19) is set in the main
program before the cycle is called or applied according
to the basic setting of this G group on the machine. It
cannot be altered in the contour subroutine.
If the contour subroutine is shorter, alarms 10933 "The
contour subroutine contains too few contour blocks"
and 61606 "Error in preprocessing contour"
and the cycle is aborted.
4-298
Interrupted paraxial cut
X
G4 G4
SINUMERIK 840D/840Di/810D Programming Guide Cycles (PGZ) – 11.02 Edition
4
03.96
09.01
DAM
G1
Infeed
movement
G4 G4
Z
© Siemens AG, 2002. All rights reserved