Civil Engineering Reference
In-Depth Information
New design of the upper die of the preforming operation and the resulting flow in the piping zone
during the finishing operation.
FIGURE 5.6
Optimized forging sequence: preliminary
upsetting operation, marks drawn on the initial work-
piece.
FIGURE 5.7
at the end of the process
(
Fig. 5.9
)
. It shows that the material is not homogeneously deformed in the
previously folded zone, and that further optimizations could be carried out.
So, the numerical simulation provides a powerful tool both to test a forging design and to get a better
understanding of the material deformation in order to possibly improve it. Although it does not provide
any designing strategy, this tool makes up the basis for the optimal design techniques.
Design Techniques Based on Artificial Intelligence
In a first time, it seems natural to use the Expert Systems technique to solve the present design problem.
One the one hand, it can provide a fast initial analysis of the problem, and suggest a first design [Len94].
On the other hand, it makes it possible to keep the expertise of experienced people, which is stored both
in the data base of the system and in the set of rules. Finally, as the other optimization techniques
described in the following, it helps in defining standard design rules and so provides a consistent
methodology throughout a company. Thus expert systems have been developed for forging problems
[4, 38]. However, it seems that this approach faces some basic difficulties. First, the human expertise is
difficult to gather, because it is difficult to clearly describe a thought process, and because the vocabulary
used is not always well defined. The same phenomena can be described with different words, in different
companies and even sometimes inside the same company. Some persons may also consider a certain
