CAM utilizes computers in the control and operations of the manufacturing process.
There are two main applications for Computer-Aided Manufacturing:
Where the computer directly controls a manufacturing operation.
Where the computer is used to support the manufacturing process, for example inventory Control and CNC part programming.
The application most commonly associated with CAM is CNC part programming. Generally, the application involves either defining the part geometry or retrieving it from an existing file and then describing the tool path including the feed rate , coolant, and work holding. Next, the program is run through a process called post-processing in which a CNC file is generated.
A direct link between product design and manufacturing can be
established using CAD/CAM software. Product engineers use a CAD system
to establish the part geometry, dimensions, and tolerances. This design data can be transferred to the CAM system where the part programmers develop the CNC program to machine the part.
A CAD/CAM system can consist of separate or integrated CAD and CAM
software. For a system using separate CAD and CAM packages, transfer of
drawing geometry using either direct or indirect translation is
required. In this case, part geometry is first created on the CAD system
and then transferred to the corresponding CAM system. After the
geometry has been recreated in the CAM system, the programmer specifies
the tools that will be used. Detail information for each tool, such as
material, diameter, number of flutes, and length, will be specified (top of page). Next the order of the machining process will be established (above). And finally a tool path with proper feed rate information is provided (below) .
Most CAM systems provide interactive graphic animations as above to verify the NC part program
.An integrated CAD/CAM system is a dedicated system that will allow the
user to create product geometry and generate CNC programs all in one
package. Data transfer from CAD to CAM is not required, and there is no data compatibility problem. This feature is important since it ensures the accuracy and reliability of the data.
CAD/CAM is an acronym for Computer Aided Design / Computer Aided Manufacturing. In essence CAD is simply a drafting board in a computer
and facilitates engineering and design with a monitor and a keyboard
instead of a paper and pencil. The drawing is saved in an electronic data file for editing.
CAM
is what can be done with the electronic data to help manufacture the
engineered part represented in the electronic file. Although there can
be hundreds of different manufacturing processes (stamping, forging,molding,
etc) “CAM” when teamed with “CAD” as in “CAD/CAM” has come to refer
almost exclusively as the process of machining the CAD geometry on CNC
machinery. Of course the computer file alone cannot machine a part nor
can the computer. But with a CAD/CAM system the electronic CAD file can
be used to create another file of tool paths that can be fed into the
controls of the CNC machinery.
In the 60's and 70's CAD/CAM systems were comprised of expensive mainframe computers and minicomputers. Because of rapid advancements in computer technology, the personal computer (PC) is now being used for most systems.
CAD/CAM systems are responsible for significant acceleration in the industrial automation processes.
A typical PC-based CAD/CAM system begins with a personal computer (PC). This computer should have enough power and memory and must be properly configured to effectively run the software .An input device or two will also be required. Normally this would consist of a mouse and a keyboard. Output devices are also needed such as a printer or plotter to generate blueprints, CNC programs, and tool sheets or other necessary paperwork. The system would also include CAD/CAM software. Selecting the correct software to meet the requirements of manufacturing application is perhaps the most important aspect of your system.
CAD, at its most basic, is a geometric modeling system used to produce two dimensional or three dimensional
engineering drawings in a computer. CAD is the use of a computer to aid
in the total design process. The design process involves identifying a
need, generating possible solutions to meet that need, evaluating each
solution to determine its merit, and developing a detail model so it can
be built.
The computer can aid in most steps in this design process.
Currently, the primary use of CAD is in the three-dimensional
models from which engineering drawings and CNC part programs are
produced almost automatically. A drawing is developed in the computer
aided design process, without the need to fabricate a prototype, so all the testing and analysis can be performed and a part program can be generated.
The major goals of CAD for manufacturing are to increase productivity and create a database for manufacturing
CAD helps the designer or drafts person to visualize a design on
the computer screen. The designer can make changes and get immediate
feedback on the results. Current CAD software also allows for analysis
and testing of components before manufacturing the actual part.
Comment:
This is a very important part of modern manufacturing expertise. The
increased use of CAD- based engineering analysis tools such as "finite
element analysis" has increased the quality of product world wide. The
automobile industry can make cars that last longer, run cooler, and
provide more power/economy due - in great part - to the ability of the
design engineer to test models in a computer before making the first
part. Aerospace, construction, medical, and all of the other design
manufacturers have benefited as well. R.S.
