Intersection Procedure For Polynomials; G461/G462 Approach/Retract Strategy Expansion - Siemens SINUMERIK 828D Function Manual

18.5.12

Intersection procedure for polynomials

Function
If two curves with active tool radius compensation form an outside corner, depending on the G code of the 18th
group (corner behavior with tool compensation; G450 / G451) and regardless of the type of curves involved
(straight lines, circles, polynomials):
• Either a conic is inserted to bypass the corner
Or
• The curves involved are extrapolated to form an intersection.
If no intersection is found with G451 activated, or if the angle formed by the two curves is too steep, switchover to
insert mode is automatic.
The intersection procedure for polynomials is released with the machine data:
MD20256 $MC_CUTCOM_INTERS_POLY_ENABLE (Intersection process possible for polynomials)
Note
If this machine data is set to inactive, a block (can be very short) is always inserted (even if
transitions are almost tangential). These short blocks always produce unwanted drops in
speed during G64 operation.
18.5.13

G461/G462 Approach/retract strategy expansion

Function
In certain special geometrical situations, extended approach and retraction strategies, compared with the
previous implementation, are required in order to activate or deactivate tool radius compensation (see figure
below).
Note
The following example describes only the situation for deactivation of tool radius
compensation. The response for approach is virtually identical.
Example
G42 D1 T1
...
G1 X110 Y0
N10 X0
N20 Y10
N30 G40 X50 Y50
Basic Functions
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
; Tool radius 20 mm
18.5 Tool radius compensation 2D (TRC)
W1: Tool offset
1493