Siemens SINUMERIK 840Di sl - Page 369

Tool offsets
8.11 Smooth approach and retraction
Fundamentals
Programming Manual, 11/2006, 6FC5398-1BP10-2BA0
369
Example
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• Smooth approach (block N20 activated)
• Approach motion with quadrant (G247)
• Approach direction not programmed, G140 is operative, i.e., TRC is active (G41)
• Contour offset OFFN=5 (N10)
• Current tool radius=10; thus the effective offset radius for TRC=15, the radius of the SAR
contour=25, so that the radius of the tool center point path is then 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 on to Z0 with FAD=200
– Approach circle in X-Y plane and following blocks with F1500 (in order for this speed
to become active in the following blocks, the G0 active in N30 must be overwritten by
G1, otherwise the contour would continue to be machined with G0)
• Smooth retraction (block N60 active)
• Retraction motion with quadrant (G248) and helix (G340)
• FAD not programmed, since irrelevant for G340
• Z=2 in the start point; Z=8 in the end point, since DISCL=6
• When DISR=5, the radius of SAR contour=20; that of the tool center point path=5
Retraction motions from Z8 to Z20 and the motion parallel to X-Y plane to X70 Y0
$TC_DP1[1.1]= 120
;Tool definition T1/D1
$TC_DP6[1.1]=10
;Radius