One of the new features in SOLIDWORKS Plastics 2016 is the Runner Domain for Plastics Professional and Plastics Premium. If you’re not familiar with domains in the SOLIDWORKS Plastics product, a domain is how Plastics recognizes different volumes in the CAD file. The domains in SOLIDWORKS Plastics 2016 are cavity, runner, insert, cooling channel, and mold. Depending upon the complexity of the analysis you are solving, you may have all five domains present in a single analysis.
In the following example, I am using three domains: cavity, insert, and runner. The cavity is, of course, the eventual finished part we will utilize in our design. The insert is a component that is inserted into the injection mold tool prior to molding the cavity. This is commonly done for threaded applications where repeated use of the fastener is expected that would otherwise preamturely wear any threads machined into the plastic as a secondary operation. Finally, the runner domain is the portion of the injected plastics that routes the molten plastic from the injection mold machine nozzle to a location on the cavity that will eventually become the finished part.
Let’s start by looking at the process to set up this problem In SOLIDWORKS Plastics 2015. The multibody part has the three components necessary for my analysis. In the initial solid mesh dialogs, you see I only have the options for cavity and insert that pertain to my current analysis. The body that represents the runner is initially included in the cavity domain.
If the intent of our analysis is only for Fill and Pack, or up to the point where the part is to be ejected from the tooling, then leaving the runner body as part of the cavity domain is acceptable. If, however, we also want to analyze how the part will warp after ejection, there are a few other things that must be considered. If the sprue and runner is not detached from the part upon ejection and cools with the part, we don’t have to do anything with the analysis. If the sprue and runner are removed from the part at ejection and prior to final cooling outside of the injection mold tool, we must take the additional step in SOLIDWORKS Plastics to specify the volume representing the runner as ‘runner element’.
This additional step insures that the Warp results are correctly calculated. While specifying the Runner Elements by box selecting in the graphics window is not difficult, it can be time consuming. I have also found that my selection technique tend to “grab” more of the model and mesh than what I need to, which forces me to have to both select and eventually deselect portions of the model related to the runner. That’s just a waste of time!
In SOLIDWORKS Plastics 2016, the process of specifying the runner is greatly simplified. During the initial setup of the domains, we only need to select the volume representing the runner and assign it to the appropriate domain. This alleviates the need to perform the secondary setup specifying the mesh regions that are runner elements. Using the new Runner Domain feature in Plastics 2016 automatically selects all of the elements from the new domain and pre-assigns them as runner elements. One step in my analysis pre-processing has been eliminated!
The new Runner Domain feature is definitely going to save setup time in many of the Plastics analyses that I perform. Faster setup time means I can spend more time working on other activities, design, and analysis work. Be sure to take a look at what is new for the upcoming version of SOLIDWORKS products. Now go make your products better with SOLIDWORKS Simulation!