Fast Retraction During Thread Cutting (Lfon, Lfof, Dilf, Alf, Lftxt, Lfwp, Lfpos, Polf, Polfmask, Polfmlin) - Siemens Sinumerik 840D sl Programming Manual

Motion commands
10.10 Thread cutting
K... :
F...:
Example
Program code
N1608 M3 S10
N1609 G0 G64 Z40 X216
N1610 G33 Z0 K100 SF=R14
N1611 G35 Z-200 K100 F17.045455
N1612 G33 Z-240 K50
N1613 G0 X218
N1614 G0 Z40
N1615 M17
References
Function Manual, Basic Functions; Feedrates (V1), Section "Linear increasing/decreasing
thread lead change with G34 and G35"
10.10.4 Fast retraction during thread cutting (LFON, LFOF, DILF, ALF, LFTXT, LFWP,
LFPOS, POLF, POLFMASK, POLFMLIN)
The "Rapid retraction during thread cutting (G33)" function can be used to interrupt thread
cutting without causing irreparable damage in the following circumstances:
● NC stop via NC/PLC interface signal: DB21, ... DBX7.3 (NC stop)
● Alarms that implicitly trigger NC stop
● Switching of a rapid input
References
Programming Manual, Job Planning; Section "Rapid retraction from the contour"
224
Thread lead in Z direction
Thread lead change
If you already know the starting and final lead of a thread, you can calculate
the thread lead change to be programmed according to the following equa‐
tion:
The meanings are as follows:
k : Thread lead (thread lead of axis target point coordinate) [mm/rev]
e
k : Starting thread lead (programmed under I, J, or K) [mm/rev]
a
I : Thread length [mm]
G
Comment
; Spindle on.
; Approach starting point.
; Thread cutting with constant lead
(100 mm/rev).
; Lead decrease: 17.0454 mm/rev2
Lead at end of block: 50 mm/rev.
; Traverse thread block without jerk.
Programming Manual, 01/2015, 6FC5398-1BP40-5BA2
Fundamentals