Approach And Retraction With Extended Retraction Strategies (G460, G461, G462) - Siemens SINUMERIK 840D sl Programming Manual

Fundamentals
2.10 Tool radius compensation
Reading positions
Points P
● $P_APR: reading P
●
3
● $P_AEP: reading P
●
4
● $P_APDV: read whether $P_APR and $P_AEP contain valid data
2.10.4.2

Approach and retraction with extended retraction strategies (G460, G461, G462)

In certain special geometrical situations, special extended approach and retraction strategies,
compared with the previous implementation with activated collision detection for the approach
and retraction block, are required in order to activate or deactivate tool radius compensation.
A collision detection can result, for example, in a section of the contour not being completely
machined, see following figure:
Figure 2-17
Syntax
G460
G461
G462
Meaning
G460:
G461:
G462:
282
and P can be read in the WCS as a system variable during approach.
3 4
(initial point)
(contour starting point)
Retraction behavior with G460
As previously (activation of the collision detection for the approach and retraction block).
Insertion of a circle in the TRC block, if it is not possible to have an intersection whose center
point is in the end point of the uncorrected block, and whose radius is the same as the tool
radius.
Up to the intersection, machining is performed with an auxiliary circle around the contour end
point (i.e. up to the end of the contour).
Insertion of a circle in the TRC block, if it is not possible to have an intersection; the block is
extended by its end tangent (default setting).
Machining is performed up to the extension of the last contour element (i.e. until shortly
before the end of the contour).
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
NC programming