Siemens SINUMERIK 808D Programming And Operating Manual page 61

Pockets in case of a stock removal cycle (Type II):
Here, the profile of the Z axis must rise or fall uniformly. For example, the following profile cannot be machined:
Differentiation between Type I and Type II
Type I: Only an axis is specified in the first block in the contour description.
Type II: Two axes are specified in the first block of the contour description.
If the first block does not contain any movement in the Z axis and actually Type II should have been used, then W0 must be
specified.
Example
Type I
G71 U10.0 R4.0 ;
G71 P50 Q100 .... ;
N50 X(U)... ;
::
::
N100.............. ;
Stock removal cycle, transverse axis (G72)
With the command G72 a stock removal cycle can be programmed with finishing allowances on the face. As compared to
the cycle called with G71, in which the machining is done through a movement parallel to the Z axis, in case of cycle G72
the machining is executed through movements parallel to the X axis. The cycle called with G72 thus executes the same
machining as the one called with G71, but only in the other direction.
Programming and Operating Manual (ISO Turning/Milling)
01/2017
Type II
G71 U10.0 R4.0 ;
G71 P50 Q100 ........ ;
N50 X(U)... Z(W)... ;
::
::
N100........... ;
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