The Impact of Precision Machining on the Future of Medical Device Manufacturing
Unlike conventional manufacturing, precision machining produces parts with submicron precision. For medical applications, this brings the crucial benefits of miniaturization, custom fit and high performance. Ralph Zoontjens, product designer specializing in 3D printing, shares his perspective on the impact of precision machining on medical device manufacturing.
Industry 4.0 in full swing and more and more companies are taking the step towards digital manufacturing. CNC machines cut materials at blazing speeds with enhanced artificial intelligence and precision, ensuring the product meets the design engineer’s intent.
With precision machining, the struggle over geometric sizing and tolerances is over, since parts will be consistent with the 3D model down to the micron.
This is a considerable achievement, as deviations are often visible on different parts of the same batch, leading to high scrap rates and failure to meet performance requirements.
Computer Numerical Control (CNC) does not retain heat-affected areas or other mechanical defects from 3D printing, which is best suited for prototypes and preoperative planning models. By milling the material as is, it retains its consistent mechanical properties to meet higher quality standards.
Precision technology isn’t just an incremental improvement. It has a radical impact on medical applications.
It is able to make durable parts that can be carried on or inside the body for a good part of life. Previously impossible solutions can now enable new forms of microsurgery, such as on embryonic infants, blood vessels or the brain.
A collection of devices relies on precision machining:
Heart monitor implants
Drug delivery systems
Kidney dialysis machines
With precision technology, product housing, internal architecture, electronic integration and wiring solutions for your biometric tracker or digital x-ray are optimized. For wearable devices like heart monitor implants or pacemakers, their minimally invasive form factor with ultra-thin wall molded micro housing is a game changer in both comfort and aesthetic sensibility.
The instruments it manufactures also enable robot-assisted surgery such as heart valve surgeries. And we’re seeing strong growth for tiny parts like septa, sensors, microelectronics, microneedles, stents, and micromachined screws. Needless to say, this requires a great deal of specialization on the part of the provider.
Precision machining creates a perfect fit for critical applications such as prosthetics and orthotics. Thanks to these technologies, people do not just feel supported, but more capable.
The following replacements are typically machined using titanium or cobalt-chrome multi-axis CNC machines with polyethylene, acrylic, polyethylene terephthalate, or polyether ether ketone plastic components:
Major joint implants for the shoulder, hip or knee
Implants for the hand, ankle or elbow
Cerebrospinal fluid diversion systems
Implantable catheter ports
Based on body scans, these complex solutions can be machined to fit the patient’s biomechanics perfectly. This is in stark contrast to traditionally handcrafted components. With a precision machined product, there is no more human error, no more patient dissatisfaction, no more second operations.
Professionals like surgeons and dentists benefit from access to precision manufacturing. Depending on their preference, they can now develop custom tools such as cutters, biopsy needles, implant holders, forceps, nebulizers and blade handles, or equip the robotic assistant with custom grippers.
In the future, healthcare professionals will use digital personalization apps to create custom components to specification, locally and on demand.
Along with functional benefits, there are also social acceptability factors – bringing hearing aids, canes and crutches, thin-walled machined biometric rings and other wearable medical devices to the fashion-savvy.
Going from traditional to precision manufacturing is like turning a wheelbarrow into a race car. Electric drive, oil-free equipment prevents contaminants as well as particle-free, fastener-free assembly with laser welding and overmolding.
Digital control and AI-enhanced software provides optimum dimensional accuracy to enable complex design features.
An advantage over other processes is the myriad of biocompatible materials it allows. Due to the high spindle speeds, this requires very specific control parameters for each material. For example, polypropylene, polyethylene, and polyoxymethylene are best for thin-walled sections.
Nylon can also be used but has a small processing window, while polycarbonate and PET require delicate temperature control. For high strength applications, consider glass fiber filled ABS.
Medical-grade metal components such as guidewires, screws, implants, and brackets are made of titanium, stainless steel, aluminum, copper, as well as Kovar, Invar, and Inconel alloys. Nitinol, a smart shape-memory material, is an upcoming option for its resistance to bending and fatigue.
For reasons of efficiency or complex geometries, a hybrid approach is sometimes deployed. Metal 3D printing can be used to develop organic internal lattice structures for lightweight components to be post-finished within tolerances using CNC.
Devices like the Apple Watch owe their supreme finish to combining aluminum extrusion with precision milling and laser equipment in a process that leaves no edge and surface burrs, even inside the watch. ‘device.
For silicone parts such as membranes, valves and gaskets, micro-molding allows parts to be made down to a few millimeters while retaining all the detail required for specific structural areas. And with optical liquid silicone rubber (LSR), glass-like transparency can be achieved.
A clear choice
Medical devices must meet stringent durability, safety, biocompatibility and sterilization standards, as well as key mechanical requirements for flexibility, lubrication, buckling resistance and torque transfer.
State-of-the-art precision machining is the way to go in almost every case, allowing full control and a huge range of materials, with the added benefit of enabling ultra-customized products.