Siemens SINUMERIK 840D sl Programming Manual page 274

Fundamentals
2.10 Tool radius compensation
● Current tool radius=10, and so the effective compensation radius for TRC=15, the radius of
the SAR contour =25, with the result that the radius of the tool center path is equal to
DISR=10
● The end point of the circle is obtained from N30, since only the Z position is programmed in
N20
● Infeed movement
– From Z20 to Z7 (DISCL=AC(7)) with rapid traverse.
– Then to Z0 with FAD=200.
– Approach circle in X-Y-plane and following blocks with F1500 (for this velocity to take
● Smooth retraction (block N60 activated)
● Retraction with quadrant (G248) and helix (G340)
● FAD not programmed, since irrelevant for G340
● Z=2 in the starting point; Z=8 in the end point, since DISCL=6
● When DISR=5, the radius of the SAR contour=20, the radius of the tool center point path=5
Retraction movements from Z8 to Z20 and the movement parallel to the X-Y plane to X70 Y0.
Program code
$TC_DP1[1,1]=120
$TC_DP6[1,1]=10
N10 G0 X0 Y0 Z20 G64 D1 T1 OFFN=5
N20 G41 G247 G341 Z0 DISCL=AC(7) DISR=10 F1500 FAD=200
N30 G1 X30 Y-10
N40 X40 Z2
N50 X50
N60 G248 G340 X70 Y0 Z20 DISCL=6 DISR=5 G40 F10000
N70 X80 Y0
N80 M30
Further information
Selecting the approach and retraction contour
The approach and retraction contour are selected with the appropriate G command from the
2nd G group:
G147:
G247:
G347:
G148:
G248:
G348:
274
effect in the following blocks, the active G0 in N30 must be overwritten with G1, otherwise
the contour would be machined further with G0).
Approach with a straight line
Approach with a quadrant
Approach with a semicircle
Retraction with a straight line
Retraction with a quadrant
Retraction with a semicircle
Comment
;Tool definition T1/D1
; Radius
; (P0 app)
; Approach (P3 app)
; (P4 app)
; (P4 ret)
; Retraction (P3 ret)
; (P0 ret)
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
NC programming