Fundamental Geometrical Principles; Definition Of Workpiece Positions - Siemens SINUMERIK 840Di sl Programming Manual

Fundamental Geometrical Principles

1.1 Description of workpiece points
Turning:
DIN 66217 stipulates that machine tools must use right-handed, rectangular (Cartesian)
coordinate systems.
The workpiece zero (W) is the origin of the workpiece coordinate system. Sometimes it is
advisable or even necessary to work with negative positional data. Positions to the left of the
origin are prefixed by a negative sign (–).
1.1.2

Definition of workpiece positions

To specify a position, imagine that a ruler is placed along the coordinate axes. You can now
describe every point in the coordinate system by specifying the direction (X, Y and Z) and
three numerical values. The workpiece zero always has the coordinates X0, Y0, and Z0.
The infeed depth must also be described in milling operations.
One plane is sufficient to describe the contour on a lathe.
Workpiece positions in the working area
For the sake of simplicity, we will only use one plane of the coordinate system in this
example, i.e., the X/Y plane. Points P1 to P4 then have the following coordinates:
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Programming Manual, 11/2006, 6FC5398-1BP10-2BA0
Fundamentals