HEIDENHAIN iTNC 530 (340 420) ISO programming - Manual (Page 300)

300 8 Programming: Cycles
8.6 SL Cy
cles Gr
oup I
8.6 SL Cycles Group I
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
G37
CONTOUR GEOMETRY.
Characteristics of the subprograms
n 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.
n The TNC ignores feed rates F and miscellaneous functions M.
n
The TNC recognizes a pocket if the tool path lies inside the contour,
for example if you machine the contour clockwise with radius
compensation G42.
n
The TNC recognizes an island if the tool path lies outside the
contour, for example if you machine the contour clockwise with
radius compensation G41.
n The subprograms must not contain tool axis coordinates.
n The working plane is defined in the first coordinate block of the
subprogram. The secondary axes U,V,W are permitted.
Characteristics of the fixed cycles
n
The TNC automatically positions the tool to the starting position in
the machining plane before a cycle. In the spindle axis the tool must
be pre-positioned to set-up clearance.
n
Each level of infeed depth is roughed-out axis-parallel or at a preset
angle (angle defined in Cycle G57). In the standard setting, islands
are traversed at safety clearance. In MP7420.1 you can also define
that the TNC should rough-out individual pockets separately,
plunging only once for each pocket.
n
The TNC takes the entered finishing allowance (Cycle G57) into
consideration.
Example: Program structure: Machining with SL
Cycles
%SL G71 *
...
N12 G37 P01 ...
...
N16 G56 P01 ...
N17 G79 *
...
N18 G57 P01 ...
N19 G79 *
...
N26 G59 P01 ...
N27 G79 *
...
N50 G00 G40 G90 Z+250 M2 *
N51 G98 L1 *
...
N60 G98 L0 *
N61 G98 L2 *
...
N62 G98 L0 *
...
N999999 %SL G71 *
The memory capacity for programming an SL cycle (all
contour subprograms) is limited to 48 kilobytes. The
number of possible contour elements depends on the
type of contour (inside or outside contour) and the number
of subcontours. For example, you can program up to
approx. 256 line blocks.
With MP7420 you can determine where the tool is
positioned at the end of Cycles 21 to 24.