High-performance grinding solutions for medical technology

Innovative grinding solutions are an important component in the manufacture of medical technology. In order to achieve the required surface quality, a specialist offers individual high-performance grinding solutions tailored to the respective process.

From pacemakers and implants to artificial knee or hip joints - medicine is developing at a particularly rapid pace thanks to ever new diagnostic and treatment procedures. Modern medical technology is an important component of this. With its Norton brand, Saint-Gobain Abrasives is the technology leader for innovative grinding solutions and is a long-standing and recognized partner of medical technology manufacturers. The specialist offers individual grinding solutions tailored to the respective process, which are not only crucial for the required surface quality and accuracy of the products produced, but also meet the high expectations in terms of repeat accuracy and service life.

The range serves a wide variety of applications and starts with - seemingly - simple products such as hypodermic needles. Drawing blood is part of everyday life in every doctor's surgery and each of us has had to be "pricked" at some point. How unpleasant this "prick" through the skin is for the patient depends crucially on the quality of the injection needle. This is why particularly high quality standards apply to medical devices and therefore also to their manufacture.

"Hypodermic needles are a good example of how important precision is in the manufacture of medical technology products," says Rocco Santoro, Area Manager and Application Engineer at Saint-Gobain Abrasives. "Because if the needle tip is not absolutely burr-free, the puncture can be very painful. In collaboration with medical technicians, we have developed grinding solutions that guarantee the requirements for smooth, homogeneous surfaces and all shape tolerances and that are tailored precisely and individually to the needs of our customers. At the same time, our solutions help to increase the productivity of the entire manufacturing process. We also offer suitable grinding solutions for machining other medical technology products, such as orthopaedic knee and hip implants, where maximum precision is also essential. Ultimately, perfectly manufactured medical products ensure better therapies and applications for patients, thereby contributing to health promotion and better recovery."

In order to optimally machine medical technology products and achieve the required quality, various process steps and different grinding tools are required during these steps. "When designing the specification of our grinding tools, the material and the dimensions of the workpiece to be machined are the first things to consider," explains Rocco Santoro. "Our customers also benefit from our many years of expertise in order to obtain an optimum grinding solution adapted to their process." An important step, especially in the production of hypodermic needles, is the cutting of the cannulas. These are brought to the required diameter and material thickness in several steps by rolling, welding and drawing and then cut to the required length using a cutting wheel. To achieve optimum results in this process, Norton provides its customers with the high-performance, non-reinforced NrCo cut-off wheels. These are designed for use on stationary machines and can be used in dry or wet conditions, depending on the type of bond. They are characterized by a burn-free and particularly fast, precise cut as well as a long service life with high cutting performance.

In the grinding process for injection needles, but also for blood lancets or infusion sets, the cutting edges (inside) and edges (outside) of the needles are machined. The choice of grinding tool is crucial for the quality of the surface finish. The cutting edges and edges must be absolutely burr-free after processing, as otherwise increased pressure pain can occur when the needle is used and the wound edges of the puncture site can "fray", which in turn can unnecessarily prolong wound healing (of the puncture site). To achieve this desired quality, Norton recommends resin-bonded silicon carbide grinding wheels with a grain size of 400 - 600, which, in addition to cool grinding, also offer excellent self-sharpening. Norton also offers non-abrasive polishing belts for the final polishing of the cannula surface. The belts are easy to handle and clean, particularly robust and resistant. They do not rust or oxidize and can be used wet or dry. The polishing belts ensure the perfect surface shine and, like the aforementioned tools, are precisely matched to the processing of hypodermic needles.

Precision and quality are also crucial in the manufacture of orthopaedic knee and hip implants. Norton Winter offers Vitron7, a high-performance ceramic cBN high-performance solution of the latest generation, for optimum surface grinding and the desired profiling. The discs are manufactured to order and are characterized by a particularly even distribution and load of the individual cBN abrasive grains in the abrasive coating.

Norton NORaX, a high-performance and durable abrasive belt with a unique microstructure, is available to give the implants the final polish. The fine 3D structure of the flexible abrasive belts enables the release of new, sharp abrasive grains thanks to even wear, resulting in a service life that is up to five times longer than that of traditional belts.

Norton offers a wide range of individual grinding solutions for machining medical products that are precisely tailored to the respective process and customer requirements. In order to achieve maximum efficiency and the desired workpiece quality with the respective tool in the production process, the setting on the machine and the optimization of the process is accompanied by the experienced application engineers and defined together with the customer on site. Rocco Santoro: "As a system provider, we develop and offer our customers in the medical technology sector a complete portfolio for the grinding machining of their products. Our strong team from research and development, product management and application technology is in close contact with our customers so that they can always offer the right grinding solution in the future. Our customers and contacts in medical technology know and appreciate this." (OM-11/23)