Siemens SINUMERIK 840D sl Function Manual page 54

W1: Tool offset
2.5 2D tool radius compensation
Axes
The continuity condition is observed in all three axes. It is thus possible to program a
simultaneous path component perpendicular to the compensation plane for approach/
retraction.
Only linear blocks are permitted for the original approach and retraction blocks with KONTT/
KONTC. These programmed linear blocks are replaced in the control by the corresponding
polynomial curves.
Exception
KONTT and KONTC are not available in 3D variants of tool radius compensation (CUT3DC,
CUT3DCC, CUT3DF).
If they are programmed, the control switches internally to NORM without an error message.
Example of KONTC
The two figures below show a typical application for approach and retraction with constant
curvature:
The full circle is approached beginning at the circle center point. The direction and curvature
radius of the approach circle at the block end point are identical to the values of the next circle.
Infeed takes place in the Z direction in both approach/retraction blocks simultaneously.
The associated NC program segment is as follows:
$TC_DP1[1,1]=121
$TC_DP6[1,1]=10
N10 G1 X0 Y0 Z60 G64 T1 D1 F10000
N20 G41 KONTC X70 Y0 Z0
N30 G2 I-70
N40 G40 G1 X0 Y0 Z60
N50 M30
Explanation:
In this example, a full circle with a radius of 70 mm is machined in the X/Y plane. Since the tool
has a radius of 10 mm, the resulting tool center point path describes a circle with a radius of 60
mm. The start/end points are at X0 Y0 Z60, with the result that a movement takes place in the
Z direction at the same time as the approach/retraction movement in the compensation plane.
54
Milling tool
Radius 10 mm
Full circle
Function Manual, 06/2019, A5E47435126B AA
Tools