As a professional engineer, Darryl Rozelle from Chaska, Minnesota, solves complex problems. With over 30 years of experience, Darryl Rozelle specializes in manufacturing process development. Medical molding is one of the most important aspects of this field.
What Is Medical Molding?
Medical molding is part of the manufacturing industry. By producing medical parts from plastic, this tool can create FDA-approved devices. Engineers like Darryl Rozelle help produce safe medical components to be used by both patients and doctors.
Molding with additional plastics is also used in a variety of other industries. This is common because of its ability to create cost-efficient and safe products. Since plastic is used for cooking, pet toys, and plenty of other reasons, this process is used in plants and factories worldwide. Even plastic pens have mold components used by specific manufacturing processes.
The typical material used for medical molding includes a variety of plastic forms. Thermoplastics, a common type of plastic found in medical molding, are polymer resins. This creates a soft material when heated. Because thermoplastics do not undergo chemical property fluctuations, they can be heated and cooled multiple times depending on the texture desired.
Different Types of Medical Molding
Darryl Rozelle has seen multiple forms of the molding in the manufacturing business. The most common forms of medical molding allow materials to be recycled and depend on the proper temperature use.
Gas-Assisted Injection Molding
Using gas for medical molding can help improve the overall appearance of a medical device. This minimizes the risk of unwanted marks. The mold cools at an uneven temperature by injecting resin without the proper pressure. The thicker areas of mold tend to cool at a slower rate than the thinner spots. The molding has dips and valleys that look out of place when this occurs.
Through channels already built into the wall, nitrogen gas is injected into the medical mold to smooth the uneven sides. This is accomplished when a path is created through the thicker sections causing pressure to manipulate the resin. Complex medical devices seen on the outside of the body are usually manufactured with a gas-assisted injection.
Metal Injection Molding
Plastic is not always better for every medical device. Devices that are smaller in size or need flexible components often do better with metal. Metal injection molding is made from several different metals and requires atomization technology.
The powder is made up of both metals and a plastic binding agent. This is used to make the manufacturing process easier. The binding agent is removed after injection by using thermal furnaces and solvent. Examples of medical products created with metal injection molding include surgical scissors, a jaw for surgical sealer, and knee brace components.
Liquid Silicone Injection Molding
For medical parts that require the highest level of hygiene, liquid silicone injection molding is the top pick. Examples of medical parts that use liquid silicone include respiratory masks and general tubing.
In addition to cleanliness, this is often a safer option because it does not react with biological tissue. This means the device can be implanted into the body. The manufacturing process uses a clean liquid in tandem with liquid polymer.
Thin Wall Molding
Thin wall molding is an effective way to improve patient comfort. Using this molding process, a medical device can function inside the body. The walls of the medical device are much thinner than most devices and are usually under 1mm.
The base material for the walls is made with a slightly different plastic. Plastics are usually LCP, polypropylene, and nylon. These are used to help structure the walls so they will not collapse. Depending on the device itself, the material may change. This is due to slight changes in pressure and temperature. Examples of medical devices with thin wall molding include catheter ablation tools, endoscopes, and microsurgical tools.
Unique Materials
The unique material formulation can advance other molding techniques such as thin wall molding or liquid silicone injection molding. Depending on a manufacturing company, a unique material formulation may include mineral or carbon filler with a lubricity additive and a blowing agent.
Depending on the combination used, this can alter the electrical conductivity in the existing material. Different temperatures can reformulate a plastic stud or sensor to provide an even better medical device. This type of technology perfects the manufacturing process for an effective and safe device.
3D PRINTING
3D printing technology uses prototyping for an injection molded device or part. This is part of the manufacturing process of medical parts but is used slightly differently. Creating a printed prototype can make potential improvements before the actual medical device is created.
3D printing can also print injection molds using either metal or plastic. The future of 3D printing will likely increase how molding can be utilized. Printing with narrow part tolerances is likely to improve over time.
Conclusion
Manufacturing technology is advancing on all fronts. Not only can it provide the ability to combine multiple processes of the molding, but it can fine-tune medical devices. Medical molding advances shape how we live by taking a process that works and making it better.
