Siemens SINUMERIK 840D sl Programming Manual page 300

Tool radius compensation
10.4 Smooth approach and retraction
Example
• Smooth approach (block N20 activated)
• Approach with quadrant (G247)
• Approach direction not programmed, G140 applies, i.e. TRC is active (G41)
• Contour offset OFFN=5 (N10)
• 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
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• 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.
300
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
effect in the following blocks, the active G0 in N30 must be overwritten with G1,
otherwise the contour would be machined further with G0).
Programming Manual, 09/2011, 6FC5398-1BP40-2BA0
Fundamentals