Whether the injection moulding simulations software (not only Moldflow) are 90% or 95% or 99% accurate or not: we should remember that these tools (or many of these tools) have more than 20 years of development and during this time they became better end better. From the other side, as the older of us may-be remember, these tools born to contribute to develop and to realize new plastic parts and products in “concurrent” way, that is to take in account from the beginning (concept phase) the possible issues coming from the tooling phase and from the production.
Today, after many years, are we sure that, even if these tools are much better, they are used in the best way? I can not give a general answer: I can only share with you my personal experience. Twenty years ago I introduced the sistematic use of the CAE tools (not only process simulation) in a Tier 1 Supplier for car market. From more than 10 years I’m the director of a company who makes support and calculations for customers in the different market fields, in many different countries. What we have seen and we see is:
– From decades, the marketing strategy of the Software Houses that sell these tools are saying that it is enough to buy these “magic” tools to fix the problems of the plastic parts. Maybe some of you remember or used some tools having a sort of traffic light: with the green light, the part is OK; with the red light the part is not so good. And also today, the situation seems not so changed: from their perspective, each designer, in combination with his CAD system, should run injection mould simulations (from the other side, in many cases we were called to fix issues in parts already “checked” in this way);
– The use of these tools should start from the beginning (concept phase) in order to address the correct development of the parts/products, also to call around the table the different competencies. In my experience I have a lot of examples of great success of this approach who lead to thickness reductions, highly cosmetic parts with the different materials and without paint, introduction of new technologies, but also some complete change of the starting (styling) concepts (also this is a success because a lot of money and time were not wasted, but other concepts were successfully developed and putted in production);
– The good sistematic use of these tools requires not only “quite special skills” from the peoples who make the analyses but also competence and a sort of organisation model able to use in the best way the information achieved from the analyses. At the base, there is the trust not only on the tool, but on the people who makes the analyses and gives the interpretations of the results (of course the analyze and the related interpretation of the results should be honest and good in order to achieve the trust from the colleagues and/or from the customers). This organization can be quite different if the plastic injection mould simulations are performed in house or by a consultancy firm, but, in general, it requires, to be very effective, a quite large degree of freedom of the tech departments in order they can quickly activate suppliers (mould makers, consultants, ..), a good program management to take in account also the time for the analyses in the time plan, but having the possibility to recover this time with the “parallelization” of the different tasks (concurrent engineering) and in the same time to increase the robustness of the program. Unfortunately, in the latest years I have seen that the organisation models and the related procedures of the companies (specially big and quite big) seem not match this perspective and also when my company was and is involved to check style concepts, in reality, these are not concepts but already virtual plastic parts ready to tool (and in many cases, all the job done was wasted because the style concepts was not so robust).