Siemens SINUMERIK 840D sl Programming Manual page 268

Motion commands
9.14 Fast retraction for thread cutting (LFON, LFOF, DILF, ALF, LFTXT, LFWP, LFPOS, POLF, POLFMASK,
LFTXT
LFWP:
ALF= :
LFPOS:
POLFMASK:
POLFMLIN:
POLF[]:
268
The retraction direction is controlled in conjunction with ALF with G
functions LFTXT and LFWP.
The plane in which the retraction movement is executed is
LFTXT:
calculated from the path tangent and the tool direction (default
setting).
The plane in which the retraction movement is executed is the
LFWP:
active working plane.
The direction is programmed in discrete degree increments with ALF in the
plane of the retraction movement.
With LFTXT, retraction in the tool direction is defined for ALF=1.
With LFWP, the direction in the working/machining plane has the following
assignment:
• G17 (X/Y plane)
ALF=1 ; Retraction in the X direction
ALF=3 ; Retraction in the Y direction
• G18 (Z/X plane)
ALF=1 ; Retraction in the Z direction
ALF=3 ; Retraction in the X direction
• G19 (Y/Z plane)
ALF=1 ; Retraction in the Y direction
ALF=3 ; Retraction in the Z direction
References:
Programming options with ALF are also described in "Traverse direction for
fast retraction from the contour" in the Programming Manual, Job Planning.
Retraction of the axis declared using POLFMASK or POLFMLIN to the
absolute axis position programmed with POLF.
Release of axes (<axis 1 name>,<axis 1 name>, etc.) for
independent retraction to absolute position
Release of axes for retraction to absolute position in linear relation
Note:
Depending on the dynamic response of all the axes involved, the linear
relation cannot always be established before the lift position is reached.
Define absolute retraction position for the geometry axis or machine axis in
the index
Effective: modal
In the case of geometry axes, the assigned value is
=<value>:
interpreted as a position in the workpiece coordinate
system. In the case of machine axes, it is interpreted as a
position in the machine coordinate system.
The values assigned can also be programmed as
incremental dimensions:
=IC<value>
Programming Manual, 09/2011, 6FC5398-1BP40-2BA0
Fundamentals