Siemens SINUMERIK 802D sl Programming And Operating Manual page 80

Manual machining
5.4 Manual machining using cycles (functions)
Parameter
Linear infeed/
Degressive infeed
Number of thread starts
Softkey
This softkey is used to select remachining or thread recutting (thread repair).
Thread cutting
The machining sequence is as follows:
1. Starting from the current axis position, the start position for the thread (d1/z0) is
2. This is followed by infeed by the first depth of cut.
3. The controller then waits for the next zero mark from the spindle encoder in order to start
4. Once the end position for the thread has been reached in both axes, the tool is withdrawn
5. The start position for the thread is then approached in the longitudinal and transverse
6. Infeed to the next depth of cut.
7. Wait for the next marker pulse from the spindle encoder to start the axes...
8. There is now a choice of 2 options:
See also
Principle operating sequence (Page 54)
General parameters (Page 58)
80
Description
This function key is used to switch between "linear infeed" and "degressive infeed". "Linear
infeed" means that roughing always takes place at a constant depth of cut, and the internal
infeed calculation is designed so that the value for the "max. infeed depth" (m1) is not
exceeded during the entire thread cutting operation. "Degressive infeed" on the other hand
means that the volume of cut is kept constant throughout the entire thread cutting operation.
In this case too, the value for "max. infeed depth" (m1) is observed throughout the entire
operation.
The number of thread starts is defined here.
approached in rapid traverse.
the axis movements (longitudinal axis and/or transverse axis) (depending on the thread
geometry).
from the workpiece in rapid traverse.
axis in rapid traverse, observing a clearance distance.
This process continues until all cuts have been completed. An additional finishing cut to
smooth the thread is then performed and the start position for the thread is approached in
the longitudinal and transverse axes.
– Machining is now complete and the "Execute" screen can be closed with the "Abort"
softkey.
– If you wish to continue machining the thread, e.g. if thread finishing is required, press
NC Start again.
Programming and Operating Manual, 06/2009, 6FC5398-6CP10-1BA0
Manual Machine Plus Turning