Siemens SINUMERIK 840D sl Operating Manual page 431

Approach/retraction when milling external threads
1. Positioning on retraction plane with rapid traverse.
2. Approach of starting point of the approach circle in the current plane with rapid traverse.
3. Infeed to a starting point in the tool axis calculated internally in the controller with rapid
4. Approach motion to thread core diameter on an approach circle calculated internally in
5. Cut thread along a spiral path in clockwise or counter-clockwise direction (depending on
6. Exit motion along a circular path in opposite rotational direction at programmed feedrate.
7. With a programmed number of threads per cutting edge NT > 2, the tool is fed in (offset)
8. If the plane infeed is less than the thread depth, points 3 to 7 are repeated until the thread
9. Retraction on the retraction plane in the tool axis with rapid traverse.
Procedure
Turning
Operating Manual, 02/2012, 6FC5398-8CP40-3BA0
traverse.
the controller with the programmed feedrate, taking into account the finishing allowance
and maximum plane infeed.
whether it is left-hand/right-hand thread, with NT ≥ 2 only one rotation, offset in Z
direction).
To reach the programmed thread length, traversing is beyond the Z1 value for different
distances depending on the thread parameters.
by the amount NT-1 in the Z direction. Points 4 to 7 are repeated until the programmed
thread depth is reached.
depth + programmed allowance is reached.
1. The part program or ShopTurn program to be processed has been
created and you are in the editor.
2. Press the "Milling" softkey.
3. Press the "Thread milling" softkey.
The "Thread Milling" input window opens.
Programming technology functions (cycles)
8.4 Milling
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