Siemens SINUMERIK 840D sl Operating Manual page 439

Approach/retraction during helical machining
In helical machining, the material is removed down to pocket depth in a helical movement.
1. The tool approaches the center point of the pocket at rapid traverse at the height of the
retraction plane and adjusts to the safety distance.
2. Infeed to the first machining diameter.
3. The circular pocket is machined to pocket depth using the selected machining method.
4. The tool moves back to the safety distance at rapid traverse.
Machining type: Plane by plane
When milling circular pockets, you can select these methods for the following machining types:
● Roughing
Roughing involves machining the individual planes of the circular pocket one after the other
from the center out, until depth Z1 or X1 is reached.
● Finishing
During finishing, the edge is always machined first. The pocket edge is approached on the
quadrant that joins the pocket radius. During the last infeed, the base is finished from the
center out.
● Edge finishing
Edge finishing is performed in the same way as finishing, except that the last infeed (finish
base) is omitted.
Machining type: Helical
When milling circular pockets, you can select these methods for the following machining types:
● Roughing
During roughing, the circular pocket is machined downward with helical movements.
A full circle is made at pocket depth to remove the residual material.
The tool is removed from the edge and base in the quadrant and retracted with rapid
traverse to the safety distance.
This process is repeated layer by layer, from inside out, until the circular pocket has been
completely machined.
● Finishing
In finishing mode, the edge is machined first with a helical movement down to the bottom.
A full circle is made at pocket depth to remove the residual material.
The base is milled from outside in, using a spiral movement.
The tool is retracted with rapid traverse from the center of the pocket to a safety distance.
● Edge finishing
In edge finishing, the edge is machined first with a helical movement down to the bottom.
A full circle is made at pocket depth to remove the residual material.
The tool is removed from the edge and base in the quadrant and retracted with rapid
traverse to the safety distance.
Turning
Operating Manual, 05/2017, A5E40868721
Programming technology functions (cycles)
10.4 Milling
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