PrintThe following presentation by Craig Tappe from Accumold’s sales engineering team focuses on medical micro molded cannulas, specifically thin-wall cannula molding. Accumold specializes in micro molding, which involves producing very small parts with micro-sized features, tolerances, or overall footprints. The company wrote the book on thin-wall molding, overmolding, and two-shot molding.
An in-house case study demonstrated capability in thin-wall molding, successfully molding a high aspect ratio part with a 0.004” wall thickness in various resins, challenging industry norms about material limits.
Overcoming the challenges of medical cannula design
A significant portion of the presentation focused on the thin-wall drug delivery cannula molding process. This innovation addresses the need to enhance and reduce the manufacturing costs of cannulas used in diabetes wearable devices. Traditional methods, such as extrusion, chamfer grinding, flaring, and gluing, are costly and problematic. Accumold’s solution involves developing a single-piece molded cannula that improves patient safety and reduces manufacturing expenses.
Accumold’s entry into cannula development started with an eye surgery cannula, featuring a quarter-inch length and a 0.004” wall thickness with a sharp chamfer for low insertion force. Building on this foundation, they developed a cannula for cancer treatment drug delivery with similar dimensions but a 0.006” wall thickness, molded in polypropylene. Currently, their focus is on creating an even smaller aspect ratio cannula, aiming to reduce the wall thickness below 0.004”, suitable for high-volume production in the drug delivery market.
Micro Molding
The company’s approach involves testing various materials, designs, and aspect ratios to optimize cannulas for different applications. Accumold utilizes both standard and micro molding platforms, with the latter specifically designed for micro-sized features and thin walls, effectively addressing the limitations of standard platforms.
Accumold’s capabilities include prototyping and high-volume production of thin-wall cannulas, with tooling options for up to 16 cavities, enabling production volumes of up to 40 million units per year from a single tool. Their process supports a wide variety of materials, from softer materials for patient comfort to more rigid biocompatible materials, allowing for customizable designs that can be integrated into new or existing medical devices.
Micro Molded Medical Cannula
For over five years, medical partners and engineers have sought a micro-molded medical cannula. The reasons are clear: current market options are medically problematic and expensive to produce.
While some engineering challenges cannot be solved with precision plastic molding, advancements in material science and engineering technology are continually reducing this list. We are proud to now include the medical micro-molded cannula among our micro-mold successes.
Why use a micro molded cannula?
From a patient-care perspective, physicians recognize that some cannulas can be rigid and cause irritation as the body tries to expel the foreign object. Additionally, traditional medical cannulas are expensive to produce. Two-piece glued cannulas can fail when the cannula detaches inside the patient. The extrusion, tip grinding, and gluing of thin tubing onto a separate hub also present challenges. A micro-molded cannula addresses these issues.
For medical technology engineers, this innovation enables component consolidation through an intuitive interface. Molded cannulas eliminate the need for complex, low-yield processes like tipping, flaring, and gluing.
We work with you to optimize key characteristics such as flexibility, rigidity, and size, ensuring the best comfort and performance for patients. Accumold’s all-plastic micro-molded cannula simplifies the manufacturing process compared to conventional extruded cannulas.
Medical cannula micro mold materials and resins
The single-piece micro-molded cannula features a thin wall and can be molded from various materials, including polypropylene, PEBAX, and Teflon, ensuring thinness and flexibility.
Partnering with Accumold for your cannula development will significantly reduce costs and enable scalable manufacturing for applications in drug delivery, diabetes management, insulin delivery, continuous glucose monitoring (CGM), eye surgeries, and the pump market.