Siemens SINUMERIK 840D sl Operating Manual page 388

Programming technology functions (cycles)
10.3 Contour turning
● Straight diagonal line
● Circle/arc
For each contour element, you must parameterize a separate parameter screen. Parameter
entry is supported by various help screens that explain these parameters.
If you leave certain fields blank, the cycle assumes that the values are unknown and attempts
to calculate them from other parameters.
Conflicts may result if you enter more parameters than are absolutely necessary for a contour.
In such a case, try entering less parameters and allowing the cycle to calculate as many
parameters as possible.
Contour transition elements
As transition element between two contour elements, you can select a radius or a chamfer or,
in the case of linear contour elements, an undercut. The transition element is always attached
at the end of a contour element. The contour transition element is selected in the parameter
screen of the respective contour element.
You can use a contour transition element whenever there is an intersection between two
successive elements which can be calculated from the input values. Otherwise you must use
the straight/circle contour elements.
Additional commands
You can enter additional commands in the form of G code for each contour element. You can
enter the additional commands (max. 40 characters) in the extended parameter screens ("All
parameters" softkey).
You can program feedrates and M commands, for example, using additional G-code
commands. However, make sure that the additional commands do not collide with the
generated G code of the contour. Therefore, do not use any G-code commands of group 1
(G0, G1, G2, G3), no coordinates in the plane and no G-code commands that have to be
programmed in a separate block.
Additional functions
The following additional functions are available for programming a contour:
● Tangent to preceding element
You can program the transition to the preceding element as tangent.
● Dialog box selection
If two different possible contours result from the parameters entered thus far, one of the
options must be selected.
● Close contour
From the current position, you can close the contour with a straight line to the starting point.
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Operating Manual, 05/2017, A5E40868721
Turning