1 sl cycles, Fundamentals, 1 sl cy cles 7.1 sl cycles – HEIDENHAIN TNC 320 (340 55x-05) Cycle programming User Manual
Page 170

170
Fixed Cycles: Contour Pocket
7.
1 SL Cy
cles
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.
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.
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
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.
