Healthcare professionals ranging from primary care physicians to highly-trained surgeons rely on their medical knowledge to deliver exceptional care to patients around the world, with the help of expertly manufactured medical devices. As the average age of the population and life expectancies increase, manufacturers are challenged to keep pace with the rising demand for improvements to the quality of care and quality of life.
These new medical devices must be highly reliable, but they are often small and complex, making them a challenge to fabricate. Precision machining is one method manufacturers can use to consistently deliver high-quality parts. Precision machining has provided an array of benefits to numerous industries, from aerospace and automotive to the medical industry. This article will review precision machining is, and discuss its importance in medical device manufacturing.
What is precision machining?
Precision machining is just what it sounds like: a manufacturing process for removing unwanted material to create a complex final shape - but it is done at a level of accuracy that takes regular machining to a whole other level. The process is crucial not just in making production parts to exceptionally tight tolerances, but in creating machine tools and equipment that can deliver these tight tolerances.
Precision machining is the same as traditional machining, except for the tight dimensional tolerances that are required. With the right equipment, parts can be machined to tolerances as small as +0.0001”. While precision machining uses the traditional CAD (computer-aided design) and CAM (computer-aided manufacturing) software employed in normal machining processes, what makes precision machining possible is the tools and machinery used. Manufacturers should ensure that tools and machines can obtain the tolerances assigned to a part. With the right equipment, a well-developed CNC program, and a skilled operator, manufacturers can create precise parts that can be reproduced with ease and consistency - with little to no scrap. When it comes to medical device manufacturing, precision machining is used to ensure that small parts fit together precisely and function as intended.
Three ways precision machining benefits medical device manufacturing
From being able to machine a variety of materials to developing custom devices for a perfect fit, here are some of the ways that precision machining benefits medical devices:
- Produce precise devices
The use of 5-axis milling machines and electrical discharge machining (EDM) are two items that make precise machining of medical devices possible. Using 5-axis milling machines allows manufacturers to use shorter cutting tools , which enables them to use higher cutting speeds and generate less tool chatter - leading to shorter cycle times and more precisely cut parts. These machines also require less fixture preparation and allow tools to cut intricate shapes with ease, accuracy, and precision.
EDM is typically reserved for parts and materials that are difficult or impossible to machine with conventional tools (e.g., titanium) . The theory and technology behind EDM are beyond the scope of this article, but in short, EDM works by using an electrically charged wire or electrode to remove material from a workpiece. EDM, like 5-axis machining, can create complex shapes and reach depths that can seem impossible when using a traditional cutting tool - all while also leaving a highly precise surface finish that is ideal for medical devices. Since EDM is a non-contact process, it applies no force to the workpiece during processing. This allows thin walls and sharp internal radii to be manufactured with ease. The added flexibility in wall thickness and geometry gives designers more freedom to create parts optimized for the function they are to perform, rather than settling for sub-optimal functionality due to manufacturing process constraints.
With precision machining, precise, personalized prosthetic limbs, or complex parts and tools for robot-assisted surgery, can be created with ease - when just a few years ago, this would have been impossible.
- Manufacture devices from a variety of materials
In the United States, the materials used in medical settings must adhere to strict standards set forth by the Food and Drug Administration (FDA) to ensure their compatibility with the human body, ability to be sterilized, and durability. Medical products made from these medical-grade materials are evaluated for the potential risk they pose to patients. Whether these parts, like a hip joint, are implanted permanently into a patient’s body or implanted temporarily through a needle, they must adhere to the applicable FDA standards to ensure patient safety.
Commonly used biocompatible materials include medical (surgical) grade stainless steel and titanium, as well as plastics like polypropylene and polyethylene. These materials are often used alone or in combination to make a range of devices from joint implants and surgical tools to hospital beds and wheelchairs.
With precision machining, stainless steel and titanium - two materials that are difficult to machine - can be used to create parts with intricate and detailed shapes and sizes for any medical application. In fact, it is the advancements in precision machining that have made the use of biocompatible metals for implants possible in the first place. Precision machining is the go-to solution for manufacturing critical medical parts, due to the precise and smooth surfaces it can provide on biocompatible materials in extremely challenging applications.
- Create devices with a smaller footprint
Another way that precision machining supports medical device manufacturing is its ability to create miniature devices built to tight tolerances. As a result of advancements in precision machining, devices such as insulin pumps and pacemakers can now be made with a smaller footprint while retaining full functionality.
Precision machining has made the use of robotics and lasers commonplace in surgery. The manufacture of the small components that go into these devices has revolutionized healthcare and will only continue to allow the creation of more innovative products for patient care.
Previously, such devices as implantable defibrillators were too large and inconvenient to be practical. With the miniaturization made possible by precision machining, external devices like insulin pumps, and internal devices like pacemakers, are now more comfortable, and present little impediment to the wearer’s mobility - they can live normal lives.
Final thoughts
Precision machining has revolutionized manufacturing in recent years, especially within the medical industry. It has provided designers the ability to create more precise and personalized devices that have dramatically improved patient care. It has allowed devices to become much smaller. This, in turn, makes implanted devices more comfortable for patients and makes robotic surgical procedures safe and more effective. Advancements in precision machining have catalyzed innovation and growth in the medical industry and will continue to do so in the future to improve the quality of life. Contact an ACHB representative today to discuss your medical device manufacturing needs.
