Using Autodesk Moldflow for Engineering Decisions

by Jeff Higgins 5 September 2017

Is anyone else shocked to learn that Autodesk’s Moldflow products have the ability to guide its users to make decisions? Probably not! It always seems like Moldflow analysts find a reason not to do this. While Autodesk Moldflow is well respected, and known as the world’s leading simulation for Injection Molding, look at how Moldflow has grown up over the last 5-10 years. And even more importantly, how Moldflow has grown beyond the world of analysis, and into the world of detailed decision making. Let’s get started with a couple simple examples:

Making Material Decisions:

Autodesk Moldflow has been designed to provide design and analysis level information, all based on the same core technology. So, it’s really not a surprise to hear that both Autodesk Moldflow Insight an Autodesk Moldflow Adviser has the same core technologies, and even very similar outputs. What isn’t really a shock is hearing that not everyone uses, or even knows, about some of our design and engineering level analyses. The Autodesk Moldflow Molding Window Analysis is one of the most underutilized capabilities in Moldflow. And this functionality is available in both Moldflow Adviser and Moldflow Insight.

Imagine for a moment, there are 3 materials all possibly to be used to manufacture some product. How do you choose, maybe even if those materials all exist in the same family of polymer? They should all function the same, right? Maybe we just pick this cheapest one? Or the one that we use the most of?

One of the things learned about any material, is that not all materials are created equal. While many materials have similar properties, sometimes the way they achieve those properties are wildly different. This does not mean that any one material is better than another, often times they have been created for specific applications and use cases. But when working through a new design, having the information to see: energy usage, processing window, part quality, and even cycle time can make the difference good and better. It’s even possible to find a material that may be the 2% more expensive, but save me 10% in cycle time. Using an upfront analysis like the Molding Window means the implication of materials can be seen so that materials, and even alternatives, can be selected while still often in the design phase for the component.

Making Process Decisions:

Autodesk Moldflow Insight has been the leading simulation software for plastic injection molding, for as long as I can remember. Injection molding is an extremely difficult process to replicate on a day-to-day basis, and even more so when discussing what it will take to accurately simulate this process. For anyone that has spent any time in this market, the conversation of material variability, process repeatability, and “mold safe” dimensions are all common. What this means though, is that these variations are not only common, but accessed. So, how then, is a simulation software supposed to accurately replicate reality, when reality is inconsistent? The answer is quite simple: test the variability of the mold!

Using the Design of Experiments built into Autodesk Moldflow Insight, as the mold design get more and more complete, more of these types of variability tests can be done to find the impact of variation (or reality). Something as simple as cutting a mold “steel safe” can mean a drastic change to the melt front during injection. In one particular application, a weld line movement was so extreme that it was the difference between a good part, and scrap:

What made this even more challenging, the variation needed to maintain the quality criteria for this part could not even be achieved within mold tolerances. Finding this before mold construction means building a told that can produce a quality part, or having to spend months and money modifying a this mold to make the part “better”.

Using Design of Experiments isn’t just about finding problems, it’s also about understanding your process. Since weather can change, molds and materials change, and even our injection molding machines can have some inconsistencies, at times, knowing which of these are influential to a part can be critical to understanding the quality of any part.

If we understand that melt temperature is critical to maintain our part shape, then alerts and limits can be setup on injection molding machines to respect these limits, parts can be modified to be less sensitive to change, or even help to set realistic manufacturing expectations.

For the first time, answers can be found by showing variability, and illustrated live and in real-time for anyone to see. Dynamically show the impact on the part, and the results of change.



Making Geometry Decisions:

While this is something typically saved for designers and Moldflow Adviser level conversations, some incredible capabilities have been added to Moldflow Insight to make the understanding of part design even more vivid.

I know that Moldflow Adviser has always been the simulation tool thought to be the most “upfront” and “designer driven” analysis package. That has become even more clear recently, with many companies starting to implement Moldflow Adviser with CAD Designers. Not just for its ease of use, but its dynamic help and adviser capabilities.

 

These functionalities of Moldflow Adviser have given to the ability to understand how designs influence manufacturability, how designers can influence designs early, and how to understand what changes are appropriate to resolve a manufacturing problem.

Beyond this point, Moldflow Insight is also added new CAD modification capabilities, and now coupled with an automatic mesher, completely automating the process of design modification for simulation. While not full CAD functionality, it allows for basic CAD manipulations and modifications.

So, with a practical application, we can take a feature of any part, and show how the modification of the feature can influence manufacturing, part quality, and process capability:

This means understanding designs, optimizing and changing within the scope of a design, and explaining clearly what changes and variations mean to production.

Making Engineering Decisions:

Autodesk Moldflow has for too long been known as a simulation product for a single moment in time. It’s been common to apply one set of processing conditions, to a nominally designed part, with ideal material information. While this provides Moldflow users with superb information, the power for the future of Moldflow is to make engineering decisions. Autodesk supporting the “Power of Many” means that we can simulate multiple iterations automatically, utilizing Autodesk Cloud Computing, HPC (High Powered Computer-Centers), and even mass computing. Take advantage of the power at our finger tips, and use the power of engineering simulations, the power of many like DOE and Optimization, and using clear visual imagery to display what this all means, to all the parties involved. This will change the way simulation can impact the plastics industry. Revolutionize more than the way simulations are done, revolutionize how we communicate about our process and industry.