In medical injection molding, common defects like short shots, burn marks, warping, and structural weaknesses are often caused by poor design – and even a small design flaw can lead to weeks of delays that cost tens of thousands of dollars.
The good news is that these deficiencies are largely avoidable if you take proactive steps early in the design phase. Here are five smart ways to prevent design deficiencies in medical injection molding.
1. Follow PIA Guidelines
Start by ensuring your design adheres to Plastics Industry Association (PIA) guidelines. These often-overlooked standards help uncover design issues early, when they’re relatively quick, easy, and inexpensive to fix.
Following PIA guidelines also helps you design for manufacturing (DFM), which can vastly increase efficiency while cutting costs and accelerating time to market.
2. Conduct a DFM Review
A design for manufacturing review ensures your components are optimized not just for functionality, but also for cost-effective, scalable production. Without it, OEMs can spend significant time and money only to “design in” problems that don’t surface until it’s time to scale – resulting in redesigns or quality issues that inflate costs and delay market launch.
It’s not enough to prove your device can be built. You also need to prove it can be built repeatedly and profitably at scale. A thorough DFM review offers an end-to-end perspective of your medical device’s production, increasing the likelihood of market success.
3. Mold Flow Analysis
A mold flow analysis simulates how molten plastic will fill the mold cavity, allowing you to identify air traps, weld lines, hot spots, stress concentrations, and unfilled voids that can compromise component integrity or functionality.
Running a mold flow analysis before design freeze offers the opportunity to make adjustments – such as gate locations or wall thicknesses – to improve quality well before going to production.
4. Functional and Strength Testing
Functional and strength testing validates that your molded components will perform reliably under real-world conditions. These tests help uncover hidden design weaknesses that might not be visible during visual inspection.
Tensile, fatigue, burst/pressure, and other tests can catch critical issues before they become expensive or even potentially dangerous problems that could trigger safety recalls.
5. Scientific Injection Molding
Scientific Injection Molding (SIM) represents a series of tests that establish the process window the mold and press can achieve. It includes a rheology study, cavity balancing, and cooling.
By establishing this process window, SIM validates that your components can be molded reliably and repeatably, which is critical in medical manufacturing where consistency and quality must be maintained at scale.
Next Steps
In medical injection molding, design deficiencies can cause weeks of costly delays, lead to safety recalls, and doom devices to fail before they ever reach the market. However, OEMs can prevent these issues with an intelligent design strategy that follows PIA guidelines, incorporates a DFM review, and includes mold flow analysis, functional and strength testing, and scientific injection molding. The result? Lower costs, faster time to market, and increased chance of market success.
Looking for medical device design insights that improve manufacturability, scalability, and profitability? Contact us to see how Intricon can help ensure your next medical device launch goes smoothly, from initial concept to market release.