Siemens SINUMERIK 840Di sl Programming Manual page 365

Corner behavior, selectable transitions G41, G42, G450 DISC=...
DISC distorts the transition circle, thus creating sharp contour corners.
The values have the following meanings:
DISC=0 transition circle
DISC=100 intersection of the equidistant paths (theoretical value)
DISC is programmed in steps of 1.
When DISC values greater than 0 are specified, intermediate circles are shown with a
magnified height – the result is transition ellipses or parabolas or hyperbolas.
An upper limit can be defined in machine data – generally DISC=50.
Fundamentals
Programming Manual, 11/2006, 6FC5398-1BP10-2BA0
8.10 Compensation at the outside corners (G450, G451)
Tool offsets
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