As injection molding continues to evolve, there are plastic injection trends that emerge to help improve the process – allowing the industry to remain at the forefront of manufacturing. Here are three trends (specifically in plastic parts and materials) that will play a major role in ensuring the injection molding industry remains competitive:
Injection-molded products produced in the United States (U.S.) are becoming more economically attractive than products produced overseas, due in part to increasing labor costs in foreign countries and inflexible procurement schedules for overseas procurement. These growing issues can affect adjusting inventory, making it more difficult and expensive for any type of movement. In a study conducted by IndustryWeek, 70% of manufacturers cited better access to skilled talent as a reason for moving their operations to the U.S. – more than four times as many as those who cited access to talent as a reason for relocating production outside the U.S.
Choosing to manufacture within the U.S. can improve the quality and consistency of inputs and reduce the Total Cost of Ownership (TCO). Re-shoring to the U.S. can also protect and grow market share, help develop quality products and build a solid business reputation. Publicizing these initiatives can attract more business, too – just be sure to deliver and maintain the trust and confidence of previously established relationships.
2. Process Validation
Process validation will be a major factor in producing high-quality products. A validated process is considered successful when it’s stable, dimensionally centered, and has few or no adjustments from run to run. Effective processes should include the following:
Installation Qualification (IQ)
Setting specific installation and process conditions succeeds the value of life for injection-molded products. It is during this stage that the equipment and facilities used to manufacture the end product are maintained and calibrated as required. Related to plastic injection molding this would include preventative maintenance on molding machines, ensuring you have the proper size machine (shot size and tonnage), and ensuring all equipment used to inspect and accept the final product is calibrated and documented. It’s important to document initial installation settings to minimize any over-head regarding rejects.
Operation Qualification (OQ)
Determined by experimentation, this phase will allow you to gain a complete understanding of the process and demonstrate it will produce acceptable product throughout a range of parameters. Through the use of analytical processes, as well as statistical and dimensional studies, the goal is to understand and establish parameters, the variations affecting the process and to continuously investigate the process deviations, which is essential to the manufacturing process. The process will not be considered validated if it has negatively impacted the finished product in any way.
Process Qualification (PQ)
The final phase of validation will demonstrate the process is stable and capable of producing parts that meet the customers expectations. It’s vital to test products manufactured from the same production equipment and the processes that will be used for routine production to ensure consistency and accuracy. Typically, this consists of multiple manufacturing runs at your nominal process which is used to simulate different production runs.
When executed properly, IQ OQ PQ can save a considerable amount of time, money, and resources by reducing production costs related to non-conforming product being produced. Additionally, a validated and qualified process ensures lot-to-lot consistency, ultimately reducing the risk of long term failures due to an inconsistent manufacturing process.
3. Chemical Resistance
Medical, food processing and chemical processing industries are all in increasingly high demand for chemically inert materials. Many commonly used materials, especially plastics, are not made to hold up well in extreme environments. Exposure to harsh chemicals and the regulations imposed on hospitals and medical offices to frequently disinfect medical equipment can and will deteriorate untreated plastic – increasing the risk of after-market defects, liability and cost. In response, OEM’s are turning to semi-crystalline based materials to achieve the level of chemical resistance required. Though these materials can help to achieve a higher level of chemical resistance, semi-crystalline based materials have a much higher shrink differential than typical amorphous resins, so understanding chemical compounds and designing products in accordance with proper injection molding guidelines will be crucial.
According to Medical Device and Diagnostic Industry (MDDI), “Deciding which polyurethane formulation to use for a medical application is a multifaceted challenge and requires consideration of many factors. Details such as the desired mechanical properties of the end polymer to the chemicals that the device will encounter should be taken into account to ensure the product will perform its intended function over its entire lifespan.” These will all be important considerations, which tie into the manufacturing of a variety of plastic compounds, and can also impact the validation phase.
High purity, flame retardant, resistance to acids/solvents and radiation/corrosion resistance, are just a few of the highlighted aspects that remain popular within medical and injection molding manufacturing. The environmental stress that leads to cracking in medical devices can be related to many factors, including polymer morphology, chemical concentration and residual stress in molded components, MDDI reports. Studies have been conducted regarding the difference between wiping a sample with disinfectant fifteen times over a period of three days, as opposed to saturating the sample, which was useful in predicting long-term chemical resistance. These types of studies help to develop requirements that allow for the creation of chemically inert materials.
As long as the U.S. continues to intricately validate processes and remain active in product requirement decisions, the injection molding industry will remain competitive, successful and at the forefront of the manufacturing industry.