Using Moldflow & DFM to Optimize Diagnostic Product Design


The client: A diagnostics client came to Natech needing multiple components for a blood diagnostics device.

The product: The parts go inside a testing system that tests for dozens of diseases in 20 minutes with just 5 drops of blood. Results gets delivered to their phone in minutes. The device allows patients to quickly receive a diagnosis and begin receiving treatment faster.​


The client came to us with an original design that was molded by a rapid proto-mold shop. The part was molded in a soft material (polypropylene) and had unique features. There were deep inner features that had to be cored out from the bottom. To achieve this design, the parts of the tool that form them had to be very tall. However, areas that are too tall in the mold are weak, which introduced risk of breakage.​


Part Design Redesign and Optimization

Designs don’t always go straight to the press. In order to prepare them for injection molding, we have to make design changes in order to prevent part defects, unexpected costs, and longer lead times. After examining the client’s designs, our engineers performed a preventative process to see if the design was ready for injection molding.

We performed Moldflow Analysis, which allowed us to review the part design and identify potential risks in the components. Moldflow simulates the flow of plastic into a mold, which means our engineers can see how the final product would look before manufacturing. This process predicts fill patterns, identifies the best gate location, and determines where defects might appear after molding. If these issues weren’t addressed before molding, the product would have costly flaws.

After Moldflow Analysis helped us identify potential corrections, we decided to use DFIM to improve the product and mold design. We optimized the plastic part design using DFIM (Design for Injection Molding), which creates part designs around the injection molding process.

By creating a network of interconnectivity, we increased the strength of the inner features. We also reduced the length of the unsupported metal by adding a ribbed section in the part. Since it’s lower than the surface, we reduced the risk of fatigue or breakage of the mold, which prevented the client from possibly paying for new repairs and throwing their timeline off-schedule.​


By using Moldflow Analysis, we took a proactive stance to drive decisions that best serve the application ahead of time. These processes helped our clients avoid post-production part defects, corrective costs, and timeline delays. It’s essential to understand that part designs must consider how it will be injection molded to ensure overall quality of the output and increase efficiency during production.

Natech adds value by marrying your science with our technology. Going a one-stop molding shop may produce parts. However, you increase your risk of receiving low-quality parts and redesigning your product all over again. It’s important to collaborate with expert injection molders and contract manufacturers during the design phase, so you can achieve quality molded parts for your complex designs.