Simulating A Machining Operation; Overview - Siemens sinumerik 840D sl Operating Manual

Simulating a machining operation

5.1

Overview

During simulation, the current program is calculated in its entirety and the result displayed in
graphic form. The result of programming is verified without traversing the machine axes.
Incorrectly programmed machining steps are detected at an early stage and incorrect
machining on the workpiece prevented.
Graphic display
The simulation uses the correct proportions of the workpiece, tools, chuck, counterspindle
and tailstock for the screen display.
For the counter-spindle chuck and the tailstock, dimensions are used that are entered into
the "Spindle chuck data" window.
For non-cylindrical unmachined parts, the chuck closes up to the contour of the cube or
polygon.
Definition of blank
The blank dimensions that are entered in the program editor are used for the workpiece.
The blank is clamped with reference to the coordinate system, which is valid at the time that
the blank was defined. This means that before defining the blank in G code programs, the
required output conditions must be established, e.g. by selecting a suitable work offset.
Programming a blank (example)
G54 G17 G90
WORKPIECE(,,,"Cylinder",112,0,-50,-80,00,155,100)
T="NC-ANBOHRER_D16
Machine references
The simulation is implemented as workpiece simulation. This means that it is not assumed
that the work offset has already been precisely scratched or is known. In spite of this,
unavoidable Machine references are in the programming, such as for example, the tool
change point in the Machine, the park position for the counterspindle in the Machine or the
position of the counterspindle slide. Depending on the actual work offset - in the worst case -
these Machine references can mean that collisions are shown in the simulation that would
not occur for a realistic work offset - or vice versa, collisions are not shown, which could
occur for a realistic work offset. This is the reason that in ShopTurn programs, in the case of
a simulation, the program header calculates an appropriate work offset for the main spindle -
or where relevant for the counterspindle - from the specified chuck dimensions.
Display of the traversing paths
Turning
Operating Manual, 07/2010, 6FC5398-8CP40-0BA0
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