Siemens SINUMERIK 840D sl Function Manual page 88

W1: Tool offset
2.5 2D tool radius compensation
End point in front of contour
If the end point is located in front of the contour, the retraction behavior is the same as
for NORM. This feature does not change, even if the last contour block with G451 is extended
with a straight line or a circle. Additional circumnavigation strategies to avoid a contour violation
in the vicinity of the contour end point are therefore not required.
End point behind contour
If the end point is behind the contour, a circle or straight line is always inserted depending
on G450/G451. In this case, G460-G462 has no effect.
If, in this situation, the last traversing block has no intersection with a preceding block, an
intersection with the inserted contour element or with the linear section from the end point of the
circumnavigation circle to the programmed end point can result.
If the inserted contour element is a circle (G450), and it intersects with the preceding block, this
is the same as the intersection, which would be produced with NORM and G461. In general,
however, a remaining section of the circle still has to be traversed. An intersection calculation
is no longer required for the linear section of the retraction block.
In the second case (if no intersection is found between the inserted contour element and the
preceding blocks), the intersection between the retraction straight line and a preceding block is
approached.
Therefore, when G461 or G462 is active, behavior deviating from G460 can only arise if NORM
is active or if behavior with KONT is identical to NORM due to the geometrical conditions.
Note
The approach behavior is symmetrical to the retraction behavior.
The approach/retraction behavior is determined by the state of the G command in the approach/
retraction block. The approach behavior can therefore be set independently of the retraction
behavior.
Example:
Program for using G461 during approach:
N10 $TC_DP1[1,1]=120
N20 $TC_DP6[1,1]=10
N30 X0 Y0 F10000 T1 D1
N40 Y20
N50 G42 X50 Y5 G461
N60 Y0 F600
N70 X30
N80 X20 Y-5
N90 X0 Y0 G40
N100 M30
88
; Milling tool type
; Radius
Function Manual, 06/2019, A5E47435126B AA
Tools