By Sean Fenske, Editor-in-Chief

Grinding is a fabrication technology that has experienced ongoing development for decades. While it was originally more of a manual process, advanced machines that incorporate multiple capabilities help achieve a finished result more efficiently and in less time. Companies supporting this function offer an array of services that support grinding and provide value-added offerings for a superior finished outcome.

However, unlike more familiar processes to engineers, like molding or machining, grinding is not as well understood. As such, it’s important for companies to partner with organizations that are experts in the application as well as the equipment used. When pairing with such a firm, the medical device company can realize unexpected benefits and gain critical insights into its capabilities.

To help illuminate those potentially in need of the benefits grinding provides, two representatives from Medical Manufacturing Technologies (MMT) responded to a series of questions about it in the following Q&A. Mark Bannayan, Vice President of Sales (Grinding Technology), and Tom Travia, Director of Technical Sales, Electrochemical Grinding, explain the role grinding plays in medical device manufacturing.

Sean Fenske: Can you first explain what grinding is? What is the technology used for? Is this a form of machining?

Mark Bannayan: Grinding in the medical device industry is a vital process that involves the precise removal of material from components. This is achieved using specialized grinding machines equipped with abrasive wheels or belts that rotate at high speeds.

Typically, grinding is performed with hard materials, such as stone, ceramic, or diamond wheels, which effectively eliminate unwanted material from the manufactured part. Grinding machines are programmed to follow precise instructions to achieve accurate dimensions, tolerances, and surface finishes on the component.

Precision grinding is essential in the manufacturing of medical devices, as it ensures parts meet stringent quality standards and perform optimally in medical applications. This process is applied to various components, including needles, syringes, guidewires, catheters, bone screws, and orthopedic implants. It is critical for producing parts with exact dimensions and straightness, both of which are vital for safety and effectiveness in medical procedures.

Tom Travia: Electrochemical grinding (ECG) is a combination of electrochemical (anodic) dissolution of material with abrasive action. The metal is decomposed to some degree by the direct current flow between the conductive grinding wheel (cathode) and the workpiece (anode), and includes the presence of an electrolyte solution. This process provides burr-free and low-force grinding, leaving no recast or heat-affected zones. ECG is a faster alternative to conventional abrasive grinding and tube cutoff without the need for secondary deburring. It provides solutions for applications involving many materials and industries such as medical device, aerospace, and automotive.

Fenske: When it comes to medical devices, where is grinding most often used? What types of products require grinding for their fabrication?

Bannayan: In the 1960s, several medical device companies approached Glebar, an MMT company, to help address the challenges associated with the manual grinding process for guidewires. At that time, manufacturers relied on chemical etching, a method that was not only time-consuming and unreliable but also involved highly toxic chemicals.

In 1964, Glebar introduced the first grinding machine to tackle these challenges directly. Over the years, Glebar has developed patented automated systems to tackle the increasing complexities and stringent precision requirements in the guidewire industry. This innovation has since become the industry standard for automated grinding. MMT’s suite of grinding equipment plays a crucial role in facilitating seamless guidewire manufacturing and shaping the diameters of catheters.

Travia: Additionally, MMT’s technology utilizes electrochemical processes (Tridex Technology) to enable the cutting of burr-free tubing, as well as grinding needles to achieve a specific tip geometry.

Tridex machines are used extensively in the production of needles and blades from tube, wire, and stamped materials. The main advantage is the efficiency of the process and the burr-free results, which are critical requirements for medical devices. Needle points such as lancet, franseen, chiba, menghini, trocars, and other complex designs can be easily produced on the Tridex machines at high volume, burr-free.

Fenske: What should developers keep in mind when requiring grinding for their product? What considerations are most important?

Travia: It is important for developers to consider ease-of-use, repeatability, and quality when evaluating grinding equipment or processes. Utilizing the right machine or approach can remove unpredictable variables previously associated with grinding operations.

For example, the labor force has dramatically shifted in the last 20 years, where machinists and toolmakers were employed to achieve grinding objectives previously. These processes, on average, took more than ten minutes per component to measure, whereas new processes remove bottlenecks with automated measurement for grinding, such as those offered through MMT’s Glebar and Tridex Technologies.

Bannayan: Recently, MMT unveiled its Glebar P5K Gauging System, offering the industry’s fastest and most precise scanning and profiling capabilities, combined with ergonomic flexibility for operators. With the ability to scan and profile components up to 78 inches (2 meters) in length and 0.25 inches (6.35 mm) in diameter, the P5K measures at speed of 16,000 diameter readings per second. It delivers 12 times the measurement of any currently available gauging system on the market and provides the first sit, stand, or sit/stand option, prioritizing operator comfort, flexibility, and productivity.

The P5K boosts throughput, provides invaluable predictive quality insights, and significantly minimizes scrap, while offering:

• User-friendly, intuitive software—developed with the operator in mind—ensuring traceability with fully automated measurement to guarantee objectivity and reliable results with each scan.
• Improved interface, allowing inspectors to quickly scan multiple parts with a click of the mouse to assess product quality on the manufacturing floor.
• Advanced air bearings, enhancing the longevity of the scanning head and eliminating mechanical interference, a common issue in faster scans.
• Extensive data analysis features, with optional SQL packages, complying with the strictest requirements and delivering flawless data centralization across multiple facilities.
• Increased speed, permitting operators to significantly improve in-process quality control with efficient returns to the grinder and boosting overall productivity.
• Reduced time required to establish new product recipes, accelerating deployment and minimizing training required for staff.
• More immediate insights into size compensation, providing feedback to Glebar Grinding Systems: CAM.2, GT-9AC, and GT-610 CNC.

Fenske: Are there situations when grinding can’t or shouldn’t be used? Are there material limitations?

Travia: Grinding typically has no material limitations. However, when a manufacturer has a part profile that includes multiple materials, traditional machining may be a more suitable approach in such cases.

Fenske: How is the grinding process measured, verified, and/or tested to ensure the right finish is achieved?

Bannayan: Using the P5K as an example, the machine quickly detects and measures (even minute defects) and delivers results as a clear “go” or “no go.” Parts are pulled through an optical micrometer, and measurement is automatic—free of any operator influence—providing a diameter and length reading every 30 millionths of an inch.

This machine delivers reporting, lot control, and data aggregation for SPC analysis standards and supports any combination of English and metric units (i.e., inch, cm, mm). With point-to-point dimensioning, achieved by clicking on part features and unlimited zoom capabilities, this helps ensure the right finish is achieved. In the same vein, warning tolerances can be set to alert the operator before a part goes out of tolerance, and all data, templates, results, and raw scan information are stored for product traceability.

Fenske: What services complement grinding for medical devices? Is there specific preparation that needs to be done or post-grinding processes? Does MMT provide these?

Travia: There are a variety of other services that complement grinding for medical devices, including balloon forming, hole punching, coiling, and catheter tipping, among others. Depending on the finished device, these services are complementary to one another.

Balloon forming is typically utilized for balloon catheters. This process involves shaping and stretching thermoplastic material into a balloon-like structure through the application of heat and pressure. It is essential for producing medical devices that require balloon technology for functions such as dilation, stent deployment, or drug delivery within the body. Balloon forming ensures precision, efficiency, and cost-effectiveness in medical device production, making it a vital step in creating devices used in various medical procedures, including angioplasty and stenting.

Hole punching in medical devices is a manufacturing process that creates holes or perforations in medical-grade plastic sheets or films. This technique produces components used in various medical devices and equipment. Specialized equipment is employed to punch or cut the plastic sheets or films into precise shapes and sizes. The resulting components can include filters, membranes, gaskets, seals, and other functional parts utilized in medical applications such as drug delivery systems, diagnostic devices, and surgical instruments.

Coil winding involves creating precise wire coils used in advanced medical equipment. These coils are essential for powering and connecting components in tight and delicate spaces, such as implants, catheters, and sensors. The process requires ultra-precision techniques along with micro coils and materials tailored to meet the specific needs of devices like catheters, implants, and neurostimulation tools. The miniaturization of medical devices is a significant trend in healthcare, and it is enabled by coil winding. This allows for the creation of smaller, more portable tools that can be used in complex surgeries or implantations. Coil winding is essential for the miniaturization of medical devices, ensuring they perform well, are safe, and have a long lifespan.

Catheter tipping is comprised of shaping the distal or proximal end of the catheter to meet specific requirements, such as minimizing vascular damage and enhancing patient comfort. This process can be carried out using various methods, including heat tipping and RF tipping, each offering different levels of precision, material compatibility, and production speed.

Through MMT’s comprehensive suite of brands, these critical processes can be completed with one partner.

Fenske: Do you have any additional comments you’d like to share based on any of the topics we discussed or something you’d like to tell medical device manufacturers?

Bannayan: MMT is dedicated to serving as the industry’s trusted partner for medical device manufacturing operations. Our comprehensive approach streamlines processes from product development to final production, ensuring consistency at every stage—all with customer success at the forefront.

Integrating MMT solutions can simplify the complexities of coordinating multiple vendors, resulting in faster turnaround times and uninterrupted operations. By fostering strong collaborative relationships with every customer, we respond quickly to changes in project scope or design requirements, leading to a quicker time-to-market.

A consolidated supply chain and fewer handoffs significantly enhance the delivery of crucial medical device products to the patients who need them most, all while maintaining high product quality.

Travia: Additionally, MMT’s aftermarket support, provided through our TotalCare Service, ensures excellence in manufacturing operations globally. This service combines application expertise and technical solutions with extensive support to deliver reliable and dynamic solutions that optimize manufacturing processes and drive success.

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