An Enhanced Approach to Scientific Injection Molding

Scientific Injection Molding is a powerful, data-driven approach for optimizing the production of plastic injection molded parts. But it can only be truly effective when it is backed by robust processes and strategies for analyzing and using data collected during the molding process.

In this article, we’ll take a closer look at how New Berlin Plastics uses Scientific Injection Molding in unique ways to drive decisions during part design, tool design, and material selection to consistently produce high-quality parts.

What is Scientific Injection Molding?

Scientific Injection Molding (SIM) uses best practices and data to drive part design optimization, tool design, and the development of a manufacturing process to produce a part. The goal of SIM is to move injection molding away from being an art founded in “tribal knowledge” to a data-driven, scientifically rigorous procedure. SIM focuses on polymer behavior rather than machine behavior with the goal of creating a robust, repeatable process that reduces set-up times, scrap, and improves part quality and consistency.

Consider the analogy of cooking a steak: A typical recipe instructs the cook to set the oven to 350° and cook the steak for 20 minutes. But the quality of the finished meat may vary widely, depending upon the age and condition of the oven, elevation and atmospheric pressure and other factors.

A more precise and consistent way to cook the steak would be to use a sensor to measure its internal temperature. If the recipe instructed you to cook the steak to an internal temperature of 165° F, you would get a much more consistent result, regardless of the oven used and other variables.

Scientific injection molding offers a number of key benefits:

• It enables the molder to make data-driven recommendations that help the customer optimize their part design during the design for manufacturing (DFM) process.
• It enables the molder to create an optimized tool design based on mold flow analysis and best practices.
• It helps the molder and customer to select the right material that meets their manufacturing requirements and will perform well in the field.
• It enables the molder to formulate an optimized, repeatable, robust manufacturing process that drives as much variability as possible out of part quality.
• It enables the molder to perform in-process monitoring to reduce quality errors. The injection molding machine can be programmed to know when variability has entered the manufacturing process and it can automatically reject suspect parts.

Taking SIM to the Next Level

Like any tool, scientific injection molding is only as good as the processes and thinking that surrounds it. At New Berlin Plastics, it’s part of a larger approach that’s focused on continuous improvement, robust launch and production processes and intelligent analysis of data to quickly troubleshoot and solve production problems.

Here’s how all of the pieces fit together:

• Material selection: A material should be selected based on the living conditions that part will experience. We then make recommendations to optimize the part design based on the characteristics and capabilities of that material.
• Tool design and optimization: The tool is then designed based on both that optimized part design and the characteristics of the material. Both factors will guide the selection of the material used to build the tool (aluminum, P20 Steel, H13 Steel, etc.). Various tool design considerations will then be evaluated based on the resin selected, such as gate location, runner system, and cooling configuration. Tool design is done on-site, ensuring that the finished product is tightly focused on the project requirements.
• Developing the manufacturing process: SIM applies to the above steps, but data collection and analysis are then used to develop a robust, repeatable manufacturing process.
• Universal Process Sheet: Once the tool, material, and production process have been optimized, we create a Universal Process Sheet, an internal “recipe” that documents all of the data points regarding various attributes within the manufacturing process, such as injection pressure, end of cavity pressure and actual temperatures based on what’s going on within the mold rather than machine temperature settings.

This enables us to rapidly and reliably put that tool into production for future orders. There’s no need to tweak machine settings until it is producing high-quality parts. This recipe, along with other quality assurance processes we’ve implemented, ensures that there is a very low risk we will ever ship unacceptable parts to a customer.

How Does New Berlin Plastics Use Data Differently?

By itself, data has limited value. But when it’s used to generate key insights to improve a customer’s tooling, part quality, and total cost of ownership, that’s where the magic is. Here’s how New Berlin Plastics uses data intelligently to make a difference for our customers:

• We clearly define process windows to ensure we are not running on the ragged edge of what produces an acceptable part. This allows us to absorb as much natural variation in the process as possible without it resulting in poor-quality parts.
• We use data to efficiently identify the true root cause of any problems, so we can quickly implement changes to the correct variable. This significantly reduces trial and error.
• It enables us to correlate data to a condition to predict, prevent and contain variables that could lead to part quality problems.
• It enables us to create data-driven standards that lead to consistency between team members, projects, equipment, molds, and other elements of our process.
• It provides us with historical data, which is stored in our ERP system, to help guide future projects. This enables us to discern patterns and make informed decisions about which attributes led to the best outcomes and which practices we should avoid.
• It reveals opportunities for efficiency improvements, which helps us keep our production costs low. Our SIM practices allow us to maintain a very low level of scrap, which means there is very little unnecessary cost being passed along to our customers.

Combining data with highly optimized processes enables us to make informed decisions that expedite various aspects of launch, such as determining the final tool design, sampling to develop a process, completing a successful PPAP, and going into production.

Reach Out to New Berlin Plastics Today

New Berlin Plastics’ inspired approach to Scientific Injection Molding helps our customers to mitigate risk and reduce unnecessary costs. Contact us today to discuss your next project.