Cam Systems - Siemens SINUMERIK 828D Manual

General information on workpiece production
2.2

CAM systems

Within the context of the process chain, it is the CAM system that is responsible for the key task
of generating the NC programs. The quality of this data plays a decisive role in determining the
results of workpiece production.
This section outlines the procedure for generating the NC programs. Given the diverse range of
systems available on the market, only a brief summary can be provided.
Tool definition
Procedure when working with a CAM system:
CAD data
Fetch CAD data into the CAM system. When reading the data in, a check should be
performed to ensure that the surface geometries are free from defects, i.e. that there are no
steps or jumps. Flaws in the data such as these will manifest themselves on the surface of
the finished workpiece.
Clamping situation
Define the clamping situation and the geometry that can be freely machined in a clamping
device. Define geometries such as a zero.
Specify tools
Define the necessary tools on the basis of the machining task at hand and enter the technol-
ogy data. As a general rule, CAM systems are able to read the data in from tool databases.
Amongst other things, the tools determine which subsequent machining strategies can be
used, e.g. whether plunge cutting is possible with the tool.
Specify machining strategies
Define the machining process for the various workpiece geometries using the appropriate
strategies. First of all, roughing strategies are applied, e.g. roughing in the Z plane or equidis-
tant from the surface geometry. CAM systems offer various options from 2 1/2-axis to 5-axis
machining.
The tool paths can be generated automatically or defined manually; these include, for exam-
ple, approach and retract strategies or special milling strategies such as trochoidal milling.
The machining strategies are gradually introduced in stages as part of this procedure and are
supported by automatic residual material detection, for example.
© Siemens AG All rights reserved SINUMERIK, Manual, Mold-Making with 3- to 5-Axis Simultaneous Milling
Plane roughing strategy
2.2
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