HEIDENHAIN TNC 320 User Manual page 170

7.1 SL Cycles
Fundamentals
SL cycles enable you to form complex contours by combining up to 12
subcontours (pockets or islands). You define the individual
subcontours in subprograms. The TNC calculates the total contour
from the subcontours (subprogram numbers) that you enter in Cycle
14 CONTOUR GEOMETRY.
The memory capacity for programming the cycle is limited.
You can program up to 16384 contour elements in one
cycle.
SL cycles conduct comprehensive and complex internal
calculations as well as the resulting machining operations.
For safety reasons, always run a graphical program test
before machining! This is a simple way of finding out
whether the TNC-calculated program will provide the
desired results.
Characteristics of the subprograms
Coordinate transformations are allowed. If they are programmed
within the subcontour they are also effective in the following
subprograms, but they need not be reset after the cycle call.
The TNC recognizes a pocket if the tool path lies inside the contour,
for example if you machine the contour clockwise with radius
compensation RR.
The TNC recognizes an island if the tool path lies outside the
contour, for example if you machine the contour clockwise with
radius compensation RL.
The subprograms must not contain spindle axis coordinates.
Always program both axes in the first block of the subprogram
If you use Q parameters, then only perform the calculations and
assignments within the affected contour subprograms.
170
Example: Program structure: Machining with SL
cycles
0 BEGIN PGM SL2 MM
...
12 CYCL DEF 14 CONTOUR GEOMETRY ...
13 CYCL DEF 20 CONTOUR DATA ...
...
16 CYCL DEF 21 PILOT DRILLING ...
17 CYCL CALL
...
18 CYCL DEF 22 ROUGH OUT ...
19 CYCL CALL
...
22 CYCLE DEF 23 FLOOR FINISHING ...
23 CYCL CALL
...
26 CYCL DEF 24 SIDE FINISHING ...
27 CYCL CALL
...
50 L Z+250 R0 FMAX M2
51 LBL 1
...
55 LBL 0
56 LBL 2
...
60 LBL 0
...
99 END PGM SL2 MM
Fixed Cycles: Contour Pocket