Siemens SINUMERIK 840D sl Turning Operating Manual page 435

Interruption of thread cutting
You have the option to interrupt thread cutting (for example if the cutting tool is broken).
1. Press the <CYCLE STOP> key.
The tool is retracted from the thread and the spindle is stopped.
2. Replace the tool and press the <CYCLE START> key.
The aborted thread cutting is started again with the interrupted cut at the same depth.
Input simple
For simple machining operations, you have the option to reduce the wide variety of parameters
to the most important parameters using the "Input" selection field. In this "Input simple" mode,
the hidden parameters are allocated a fixed value that cannot be adjusted.
If the workpiece programming requires it, you can display and change all of the parameters
using "Input complete".
Approach/retraction
1. Approach of the starting point determined in the cycle at the beginning of the run-in path for
the first thread with G0
2. Infeed for roughing according to the defined infeed type.
3. Thread cutting is repeated according to the programmed number of roughing cuts.
4. The finishing allowance is removed in the following step with G33.
5. This cut is repeated according to the number of noncuts.
6. The whole sequence of motions is repeated for each further thread.
Start and end of thread
At the start of the thread, a distinction is made between thread lead (parameter LW) and thread
run-in (parameter LW2).
If you program a thread lead, the programmed starting point is moved forward by this amount.
You use the thread lead if the thread starts outside the material, for example, on the shoulder
of a turned part.
If you program a thread run-in, an additional thread block is generated internally in the cycle.
The thread block is inserted in front of the actual thread on which the tool is inserted. You
require thread run-in if you want to cut a thread on the middle of a shaft.
Turning
Operating Manual, 06/2019, A5E44903486B AB
Machine manufacturer
Various defined values can be pre-assigned using setting data.
Please refer to the machine manufacturer's specifications.
Programming technology functions (cycles)
10.2 Rotate
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