Medical device designs continue to evolve, and more new molded products and components are entering the market than ever before. Some examples include laser-based surgical tools, micro-implants, and bioabsorbable technologies. Creating smaller and more complex medical devices necessitates more experience and precision from molders. Molders must also have comprehensive knowledge of materials behavior, particularly for advanced materials. Because of these requirements, medical device makers frequently want to work with molders who are dedicated to manufacturing medical products or else have a large portion of their business dedicated to medical manufacturing.
What’s more, instead of focusing on one or two aspects of the molding process, a significant number of medical molders work in partnership with their medical device customers. They may provide all manner of needed services: design, prototype development, guidance on design for manufacturing (DFM), material selection, and full production. Further, it has become practice for molders to have the ability to successfully manage all elements involved in the molding process from design to regulatory support. This can be difficult for medical device OEMs to accomplish cost-effectively, especially when working with multiple sources. Parts are also becoming so small that in some cases a full production run can be held in one hand. Many small parts require a molder that is strong in 2-shot, multi-component, or electronically integrated parts. Medical device manufacturers are constantly designing more products that need processes like overmolding or insert molding to combine materials—for example, plastic, metal, rubber, or thin, flexible surface electrodes—to make unique physical properties or specific surfaces or textures.
To gain more insight on molding for medical manufacturing, MPO spoke with the following molders serving the medical device industry:
Donna Bibber, VP of business development at Isometric Micro Molding, a New Richmond, Wis.-based micromolding company that provides medical and drug delivery OEMs with micromolded and automated assemblies.
Frank Dilly, managing director at SIMTEC Silicone Parts, a Miramar, Fla.-based manufacturer of custom, high-quality liquid silicone rubber (LSR) and LSR 2-shot (LSR/thermoplastics) parts.
Michael Eck, mold engineering manager at The Weiss-Aug Group, an East Hanover, N.J.-based firm that provides precision metal stamping, complex insert molding, custom assembly, progressive die tooling, and precision medium gauge complex stampings and assemblies.
Clay Hommel, an engineer at Injectech LLC, a Fort Collins, Colo.-based supplier of fluid-control components to medical device OEMs, biomedical/pharmaceutical manufacturers, veterinary suppliers, and industrial businesses.
Larry Knipple, VP of research and development at Injectech LLC.
Dan Lindsay, business development manager at The Weiss-Aug Group.
Jeff Lucash, VP of sales at Baraboo, Wis.-based Flambeau Inc. Flambeau and its divisions, in conjunction with other members of the Nordic Group of Companies, form a total resource network providing customer assistance in design and specifications of injection and blow molded thermoplastic components and products, building of tools and fixtures, and contract manufacturing of complete assemblies.
Shane Piers, director of engineering at Medbio LLC, a Grand Rapids, Mich.-based contract manufacturer specializing in cleanroom injection molding of plastic components for the medical and biotechnology industries.
Steve Raiken, president of RenyMed, a Baldwin Park, Calif.-based full-service injection molder serving the medical device industry.
Rob Schwenker, VP of sales, specialty molding at Spectrum Plastics Group, an Alpharetta, Ga.-based medical plastics manufacturer of extruded, injection-molded, machine-finished, and sub-assembly solutions.
Dave Splett, VP of business development at Injectech LLC.
Nick Turner, director of quality and technology at GS Plastic Optics, a Rochester, N.Y.-based manufacturer of custom designed injection molded polymer optics.
Sam Brusco: What are the latest advances in molding technologies, and what features are they making possible in medical manufacturing?
Donna Bibber: We are micromolders and the advances are pushing to smaller and smaller parts (1,000 parts/plastic pellet, 0.00004 grams) with extremely tight tolerances (single microns) and small features on larger microfluidic components (3 micron width/depth).
Frank Dilly: 2-shot molding of liquid silicone rubber (LSR). (SIMTEC was one of the first and a leader in true, 2-shot LSR molding.) 2-shot molding allows miniaturization of medical devices and perfectly placed seals.
Michael Eck: Innovation in molding technologies is an ongoing process, often tied to innovation in other procedures such as 3D printing, or advances in areas such as materials. Rapid prototyping using 3D printing has advanced, allowing printed parts to simulate molding. 3D components are now being used as organ implants. The new hair-thin plastics open future perspectives in the innovation of polymer-based therapeutics. At the design stage, rapid prototyping allows molders to create physical prototypes to verify form, fit, and function before finalizing the mold design. Advancements in moldflow simulation software has given mold designers and molders a precise prediction of processing requirements and improving the part design.
Jeff Lucash: Plastics is advancing medical manufacturing by replacing glass and metal applications with lower-cost plastics applications. Features of advancing molding technologies include rapid prototyping and micromolding, along with improved processes and advancements in controls and precision.
Shane Piers: Materials are advancing faster than how one injects melted polymers into a piece of steel.
Steve Raiken: Automation technology is advancing and moving to lower volume molding. Technologies such as in-line vision inspection have become affordable and more reliable. The molding process is more of an inter-communicating work cell with other automation in lower volume production.
Rob Schwenker: With surgeries becoming less invasive and a growing market in precision surgeries like distal extremities, part sizes are getting smaller. While not totally new, advancements and better understanding of what micromolding can achieve in part features is moving this segment beyond part size alone. This trend is also increasing the overall level of precision in molded components and allowing medical device makers to achieve better quality.
Brusco: What material advances are impacting molding process capabilities, and how are they making an impact?
Bibber: Material suppliers are opening their eyes to micromolding in recent years as a lower volume but high-value business segment. Melt flow rates of 15 g/10min or higher are generally required with much tighter ranges in melt flow rate due to the much tighter processing windows micromolders experience.
Dilly: New grades of LSRs—self-adhesive grades with good adhesion to PC (polycarbonate) and new grades with improved processing properties are coming to the market offering wider use of 2-shot technology.
Eck: Polymer physical material properties are being formulated to unique functional features, such as antimicrobial materials that inhibit bacterial growth on the molded part.
Lucash: Molding process capabilities have been impacted by advances in optical material clarity and engineered resins, resulting in increased material strength, higher impact properties, and longer part life expectancy.
Piers: We continue to monitor the capabilities of 3D/additive printing. While we don’t believe 3D printing will replace high- volume molding production anytime soon, we can see the technology developing to a point where lower volume production runs of 5,000 pieces will be plausible. This could be especially true for components made out of PEEK, which tend to have complex geometries that are challenging to mold.
We believe additive printing will have larger impact in the mold tooling arena. We have already had 3D printed cavities products for us and 3D printed slides.
Additive printing gives mold makers much more freedom in how they might design a tool. The constraints of how one might machine this needed detail or feature are greatly reduced with additive printing.
Raiken: None, really. Medical molding has limited ability to use plastic additives due to regulatory concerns.
Schwenker: Continuing advances are being made in biomaterials—both resorbable and non-resorbable polymers—to improve implant performance and reduce inflammation and other minor patient discomforts. These material improvements often require even more unique material handling and tighter, more exact molding process controls. Outside of the biomaterial/implantable marketplace, the new material advances have allowed for plastic components to be considered for more demanding applications as more polymers can stand up to autoclaving sterilization or provide more functionality.
Dave Splett: Material manufacturers are being pushed to create materials that meet all necessary standards for medical OEMs. We’ve experienced customers moving away from polycarbonate, for example, because it is not BPA-free.
Brusco: What do OEMs look for when choosing a medical molder?
Bibber: Experience in material, size, type of market segment, and quality systems and facilities that also reflect their market needs. For example, drug delivery and fluid path components and assemblies require much stricter bioburden and particulate specifications than those of medical disposable devices. A new level of cleanliness, process mapping, and a solid risk mitigation strategy are required as early as the quoting stage to mitigate scaling risks from prototype to pilot to production.
Dilly: First and foremost, OEMs are looking for quality, hygiene, and process stability, and our highly-automated, clean facility and skilled technicians deliver and align perfectly.
Larry Knipple: When OEMs choose a medical molder, they are looking for trust and flexibility. They need one who is as concerned with standards, testing, and validation as they are. They aim for a molder that understands their needs and requirements. They also look for molders that can go beyond the manufacturing step and assist further with assemblies.
Dan Lindsay: It is a well-noted fact the medical market can be a regulatory dilemma. Changing regulations and legislation make for an oddly dynamic and yet rigid landscape. The minimum requirement to work as a medical contract manufacturer is ISO 13485 certification as well as FDA registration for device assembly, packaging, and sterilizing. The ability to comply with OEM-specific regulations and process controls are an obvious requirement as well. OEMs are looking for experienced partners in scientific molding and practicing IQ, OQ, PQ validations and RJG processing support, with proven experience in innovative solutions. Medical contract molders must offer highly integrated manufacturing capabilities, supplying insert molding, micromolding, metal stampings, prototyping with rapid 3D printing, laser cutting, laser etching, laser welding, and device assemblies. In-house tool building, engineering, and development capabilities are also considered as important. The core manufacturing expertise shall include medical grade thermoplastics and compounds that help create safe and effective medical and drug delivery devices. Additional added value is location, proximity to OEMs’ Innovation Centers, as well as local and international manufacturing centers.
Lucash: OEMs want a medical plastics molder with a good reputation in the marketplace; clean room molding and assembly; and a global manufacturing footprint. Flambeau has each of these characteristics, as well as medical packaging, product design, and both blow molding and injection molding.
Piers: OEMs look for experience in molding components that they are looking to source. This experience is usually demonstrated in a competitive price. ISO (and for some customers, FDA) accreditation is expected. Medbio has a history of being a technically oriented partner that can bring customers’ ideas and products into production as fast as they can approve our processes.
Raiken: OEMs want to know we are running an ISO 13485 compliant quality system and that products are produced within ISO 13485 requirements. We are 100 percent medical molding, so we don’t have products or processes in our facility that don’t meet the required medical device standards for production. Some companies seek out RenyMed specifically for our tooling capabilities. We can, in most cases, help customers with prototype builds for device testing through to validated production. Parts are becoming more complex and tolerances are tighter, which requires better tooling and disciplined processing. We use state-of-the-art methods for mold design. Our DOE for process development has been identified by one large OEM as “best practice.”
Schwenker: Reliability is probably the most important requirement. This goes far beyond part quality, which is a basic expectation at this point. Reliability means that a supplier can align their system with customer needs and develop risk mitigation strategies together. This could be in supply chain functions, business continuity planning, or long-term capacity investments. More OEMs large and small are understanding the importance of being a “True Partner” with their supplier, and these are the companies we want to be involved with.
Nick Turner: ISO certification and/or robust quality systems capable of collecting/reporting inspection data and traceability information. They also seek companies who have an IQ/OQ/PQ process to drive verification and validation activities, which establishes a baseline to add any specific OEM customer requests. If a molder has no idea what IQ/OQ/PQ is, they have to figure out the basics while also answering the customer’s specific requirements.
Brusco: How do you ensure that molding remains competitive with other manufacturing technologies? (CNC hybrid machining, additive manufacturing, etc.)
Bibber: This is always a balancing act for high-volume disposables, regardless of whether it includes micro or macro molded parts. Material waste in hot to cold or full hot runners need to be tested at the prototype stage for micromolded components because of the residence time issues associated with the size of the tiny components and the material degradation possibilities. Micromolders are in tune with matching the residence time of the screw, barrel, and plunger and have to consider the heat profile through hot runners as well. Hot runner manufacturers are now paying attention to micromolding and designing new and much smaller hot runner channels to prevent black specks and degradation.
Dilly: We are in a different space—these other technologies offer speed-to-market. However, they do not deliver the same output in terms of consistent quality and high-volume production.
Eck: New polymers continue to develop to improve medical applications such as handheld medical devices and implants. They can replace metals to reduce costs and decrease the part weight.
There are several molded grade resins on the market today that are suitable replacements for metal, ceramic, glass, or plastic machined components and guarantee better surface finish.
For tiny medical devices, micromolding can now offer a range of cost-effective alternatives for components that are miniature, complex, and require high–precision tolerances. The two big reasons to convert to micromolding are the cost savings and time savings (shorter than machining a component). Moreover, micromolding eliminates particle contamination and the potential failure mode of having particulates left after machining.
Today, the plastic manufacturing sector is experiencing a rapidly expanding automation trend, which has not only mitigated the costs associated with human error but also improved a range of other factors, such as part quality, consistency, and demand for low-cost parts. By automating the quality check process, we can ensure every part is dimensionally accurate and meets all standards.
Knipple: We see molding as being set apart from other manufacturing technologies like CNC hybrid machining and additive manufacturing, and not in competition with it. With molding, there is the capability for multiple solutions, prototyping, and assembly.
Lucash: Flambeau ensures competitive molding services by knowing current medical marketplace conditions and utilizing the latest advancements in process technologies to the advantage of its customers. We continuously implement lean manufacturing practices and work diligently to manage our material and operational costs in this very competitive and complex industry.
Piers: Medbio is focused on manufacturing and customer service excellence. How can we produce more with the same amount of inputs? How do we provide our customers with on-time deliveries, zero defects, and a cost competitive price? This translates into too many different initiatives that ultimately help us to either reduce our costs or keep them at the same level year to year. The real challenge is that the regulatory environment continues to be more burdensome and encompassing. The addition of risk assessment to the ISO 13485 standard along with the well-publicized crackdowns by the FDA on some of the larger OEMs has the entire industry on edge. As a result, every OEM is requesting more validations, re-validations, and validations with more information than ever before. These all take time and thus cost.
Medbio is focused on implementing new technologies (IoT 4.0, additive printing, integrated machine-equipment controls) and on employee training. People run the equipment, trim the parts, and make quality decisions every day. The workforce skills must constantly be updated to use the new technology we are bringing into the company safely and effectively.
Raiken: Additive manufacturing has its place, but not for production molding. We evaluated hybrid CNC machining for making molds, but the laser light form has significant limitations. The material is improving and there are some capabilities such as conformal cooling that will help build a better mold. Nothing is coming close to a production process in additive manufacturing for plastic manufacturing.
Schwenker: The goal is ultimately to provide an effective solution to improve patient care, and while we believe the improved precision and focus on quality will continue to make molding relevant, we also recognize there is a need to combine molding with other capabilities. At Spectrum Plastics Group, we often combine our extrusion expertise with our molding knowledge. We are also always looking to expand our capability portfolio to help the customers meet their complete requirements.
Splett: Other manufacturing technologies, from our experience, are more of a first step or entry level into creating components and when quantities grow, they move towards higher capacity molding to meet their needs. Our company offers smaller minimum requirements when moving from the prototype to production phase, which is unique in comparison to other molding companies.
Brusco: What aspects do medical customers often overlook or forget when specifying molded parts?
Bibber: With the parts getting smaller and smaller, the tolerances are as well—it’s just the nature of the stack-up tolerances for the overall assembly. When parts require single- or double-digit micron tolerances, medical customers tend to go to their existing suppliers and hope for the best. Breaking down the process to single or sub-micron tolerances requires a new level of precision and measurement capability. For example, tooling must be built to 20 percent of tolerance to use the remaining 80 percent in the remainder of the process, such as gage R&R (<20 percent), micromolding process (<20 percent), material lot to lot variation (<10 percent), and material drying process (<10 percent). A histogram of these variables still requires a Cpk of 1.33 or better and must be considered to be statistically valid and fully risk mitigated.
Knipple: Medical customers often overlook manufacturers’ responsibility as a component supplier to keep customers up to date with standards and product changes. Product change notifications, notice of any issues if they arise, machine updates, or material information are all important to medical customers. We strive to keep open lines of communication with our customers at all times.
Lucash: Medical customers at times overlook the expertise and design time required for this specialized market, as well as the long sales cycle due to qualification of equipment and validation of final product. It is important to remember that, though a part can be designed on a computer, it may not be easily manufactured. Some flexibility is often required when finalizing the design. An experienced mold maker with injection and blow molding knowledge and capability can assist in optimizing the design for the most cost efficient tooling and part design. A quality staff with knowledge in injection and blow molding can also assist in creating a smooth process validation experience for the customer that results in a quality part-producing process.
Piers: The true cost of what their requirements are. The difference between calling out 0.002” flash and 0.005” or 0.010” flash can be 2x in cost. We try and understand what drives the design and ask questions to ascertain what is and is not really critical for the production to function. In an attempt to make design decisions and the costs they drive, transparent Medbio has added an increased amount of detail to our quotes. Some customers, upon seeing the cost to have 90 critical dimensions with Cpks of 2.0, have come back to us and reduced the amount of critical requirements.
Raiken: What would help us most is if the design engineers had more knowledge about the limitations of plastic, both in materials and process. For example: a part with fine detail might be specified with a high-temperature plastic not being aware the steel will fatigue with the high process temperature. Other designers will assume mold splits and will design in draft, thinking they are helping the mold designer when they should consult with the mold designer on splits and drafts.
Schwenker: Many times, it is not what they overlook but what they over-specify. By discussing validation requirements up front, both customers and suppliers can understand what critical elements are needed to bring a new product to market. As a part of that, we do a lot of Design for Manufacturing to support those organizations without the internal technical staff, or even for companies that have the expertise, but may be using resources elsewhere. Wall thickness interactions, cosmetic considerations, and joining techniques to mating parts be it snap fits, sonic welding, or solvent bonding are all important elements to define during the development process.
Turner: Inspection data, lot traceability, packaging, and labeling requirements.
Brusco: Where is molding for medical manufacturing headed? What’s coming in the next few years?
Bibber: Micro medical manufacturing is heading even smaller, with combined geometry using micro automation. It’s become increasingly important to micromold and automate right at the micromolding machine. Less datum errors and less particulate are added to parts with the least amount of part handling as possible. The value to the customer to assemble in the mold or right at the mold simplifies the assembly and creates the highest level of precision in that assembly.
Clay Hommel: The industry is requiring more rigorous testing and traceability that molders must comply with. The industry will continue to move forward into strengthening requirements and responsibilities of molders.
Knipple: We see molding for medical manufacturing being outsourced more from OEMs to molding shops. In the next few years we will see the progression of the ISO 80369 standards and their dimensional and functional changes to components. The ISO 80369 standards that have been published so far are Enteral Feeding, Blood Pressure, Neuraxial, and Intravascular.
Lucash: The medical manufacturing industry is very strong and growing, with new players entering the market every year, as well as through mergers and acquisitions. Molding precision and processes will continue to advance with the discovery of new materials and additives which will contribute to competitiveness in the market.
Piers: We see medical molding and manufacturing continuing to grow at a pace of 5-10 percent. Innovation in the space never seems to stop. While we service many of the large, well-known OEMs we receive plenty of inquiries from the doctor or clinician who has the next industry-changing idea. It’s a good place to be.
Raiken: A lot of consolidation in the medical device industry; bigger companies are eating up the smaller ones. As larger OEMs buy up smaller medical manufacturers, they will consolidate suppliers as well, which will have a negative effect on the health of the industry. We will see less development of technology and less training and development of people. I think the big OEMs should help nurture smaller companies because historically entrepreneurs are much more likely to look for new technologies to make better products. The larger injection molders are less willing to take on projects where there might be unknowns.
Schwenker: We expect the medical industry and its supply base to continue to grow, but we do see continued consolidation and stratification in the value chain. Those companies that can incorporate data analysis and more automation will have an advantage in quality and precision. That being said, a “molding only” solution may not be what a “True Partner” OEM requires from us and the combination of new capabilities will be important.