If there is one methodology in any science that is universal, it is the concept of testing and controlling variables to create repeatable results. For generations, the scientific method has proved to be a reliable model of building upon knowledge and understanding the effect of change. With regard to injection molding, the scientific molding process seeks to do just that. Rather than using trial-and-error engineering, the scientific molding process seeks to break down a mythos of tribal knowledge and build upon a foundation of experiments grounded in formulaic data to standardize quality, increase repeatability, reduce scrap, and robustify production of injected molded parts.
The scientific molding process is based on one expanded mindset: Precisely control changes in the process and measure the results, then compare the results to the desired state. By monitoring exactly what’s changing, by exactly how much, and observing and recording the impact of the changes, scientific molders strive to truly engineer a process that generates products that are consistent, high quality, and to specification.
From the start of the process, scientific molders take great care to ensure that environmental factors in the material are tracked and controlled. Humidity levels in the material dryers are recorded and managed to ensure that material with consistent moisture levels are introduced to the machines each time. From the point the material enters the injection mold machine, factors such as temperature and pressure are studied to ensure that the material reaches its melting point at the same time and under the same conditions, each time.
Scientific molders study the viscosity of the material in the injection process to ensure that each shot of material is consistent in order to reduce variation, and make adjustments to ensure that viscosity remains consistent throughout production. They also measure the amount of plastic that enters each cavity- and when- to ensure balance between cavities in multi-cavity molds. Imbalance is undesirable, and results are measured and monitored, and adjustments are made in order to achieve a balanced fill process.
Another way scientific molders are able to use the method to increase consistency and reduce scrap is to study the drop in pressure at several different points inside the molding process once plastic has filled the cavities of the mold. By mapping the drop-off in pressure, scientific molders can target ideal results and replicate those conditions for consistent, defect-free products.
There is a wide toolbox of studies, those mentioned above and more, that assist in measuring and taking control of the molding process within the scientific molding philosophy. The scientific molding process presents a guide for identifying variables that can change, identifying what those changes signify, and giving molders the ability to purposefully alter their process to ensure repeatability, quality, and optimize output. By understanding the science behind the process, we can continue to innovate and push the limits of what’s possible while maintaining the highest level of confidence in our products.
Working with a company that utilizes scientific molding provides many benefits to you as the customer: balance, intentionality, precision, and most importantly, consistent, high-quality parts.