HEIDENHAIN TNC 426 B

191HEIDENHAIN TNC 426 B, TNC 430
8.5 SL Cycles
SL cycles allow the contour-oriented machining of complex
contours and achieve a particularly high degree of surface finish.
Characteristics of the contour
■
A contour can be composed of several overlapping subcontours
(up to 12 subcontours are possible). Islands and pockets can form
a subcontour.
■
The subcontour list (subprogram numbers) is entered in Cycle 14
CONTOUR GEOMETRY. The TNC calculates the contour from the
subcontours.
■
The individual subcontours are defined in subprograms.
■
The memory capacity for programming an SL cycle is limited. All
subprograms together can contain, for example, up to 128
straight-line blocks.
Characteristics of the subprograms
■
Coordinate transformations are allowed.
■
The TNC ignores feed rates F and miscellaneous functions M.
■ 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 tool axis coordinates.
■
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
■
The TNC automatically positions the tool to set-up clearance
before a cycle.
■
Each level of infeed depth is milled without interruptions since
the cutter traverses around islands instead of over them.
■ The radius of ”inside corners” can be programmed — the tool
keeps moving to prevent surface blemishes at inside corners
(this applies for the outermost pass in the Rough-out and Side-
Finishing cycles).
■
The contour is approached in a tangential arc for side finishing.
■
For floor finishing, the tool again approaches the workpiece in a
tangential arc (for tool axis Z, for example, the arc may be in the Z/
X plane).
■
The contour is machined throughout in either climb or up-cut
milling.
With MP7420 you can determine where the tool is
positioned at the end of Cycles 21 to 24.
8.5 SL Cycles
kkap8.pm6 30.06.2006, 07:03191
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