Siemens Sinumerik 840D Operating Turning page 138

Section 5
Notes
B510
B510
Offset of the coordinate system
If, for example, the chips are to be broken or the tools are to be relieved, a
dwell period can be inserted between the blocks.
Dwell in seconds
Dwell in revolutions
To demonstrate the programming of dwells the already familiar program
"WASHER2.MPF" has been extended.
The switch from block N250 to block N270 takes place only after a waiting
period of 0,5 sec; the chip breaks.
N210 G00 X200 Z300
N220 T3
N230 G96 S140 F0.1 M4 D2
N240 G00 X40 Z-4
N250 G01 X30
N260 G04 F0.5
N270 G01 X22
N280 G04 S5
N250 G01 X14
N260 G00 X40
In case of relatively small diameters this time is sufficient for chip breaking.
This becomes evident if the high number of revolutions is compared to the
time of dwell.
In the case of large diameters a time-independent switching of blocks may
be more advantageous.
If the tool remains stationary at the destination point for a certain number
of revolutions the tool relief can be ascertained.
Hint:
The previously programmed values of the addresses "F" for feed and "S"
for speed or constant cutting speed remain activated in all cases.
The complete program is shown in the summary.
Page 8
Code G4 F...
(F is the dwell conjunction with G4)
Code G4 S...
(S is the number of revs. in conjunction
with G4 )
; Parting tool 3.1 wide
; Right hand cutting edge activated
; Dwell 0,5 sec
; Dwell 5 revs
840D/828D SINUMERIK Operate