CNC Machining Applications in Medical & Healthcare Industry

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CNC Machining Applications in Medical & Healthcare Industry

The medical and healthcare industry requires medical devices and parts to have high precision. The medical equipment, instruments, and implants have to be flawless as it involves human life, and any error can result in severe health complications or even death. This makes it necessary for the machining of medical devices and implants to be highly tolerant, precise, repeatable, and consistent.

The advent of 5-axis CNC machining has opened doors to easily manufacture medical parts and implants similar to human parts with high precision. These machines utilize various configurations to design intricate medical parts at speeds never before imagined while also greatly reducing any chance of error.

Features of 5-Axis CNC Machining

More Degrees of Freedom (DoF)

5-Axis machining consists of X, Y, and Z moving axes and A, B, C rotating Axes. This provides the machining with up to 8 degrees of freedom, and hence, the processing of more complex geometrical parts is possible and done with more precision.

Tool Guidance

In 5-Axis CNC machining, the five axes guide the milling tool on the component’s surface. Since the working angle can be adjusted at every point, an optimal angle relating to cutting speed can be ensured.

Shorter Cutting Tool

5-Axis CNC machines use shorter cutting tools, and smaller loads are fed into the machine. This helps dampen the vibration that would otherwise result in defects such as cavities and cores. Thus, the chances of breakage are prevented, and the machine’s lifespan is prolonged. This also improves the quality of finishing the parts and implants.

History of 5-Axis CNC Machining

An in-depth history of 5-Axis CNC Machining can be found in Golden E. Herrin’s work in 1995, which explains the first 5-Axis CNC Machining was invented in 1958, way before numerical control prevailed. The United States Air Force contracted Cincinnati Milacron Inc. to manufacture and test a 5-axis vertical mill for analyzing any potential feasibility. But the machine was not considered very practical then.

Later on, when Numerically Controlled machines were developed, they extended to be developed into CNC machining. Multiple programming languages were formed, and CNC started gaining quick popularity. The next evolutionary step was the development of Post-processing systems. Computer-Aided Design (CAD) programs were used to help create, modify, analyze, and improve designs. Computer-Aided Manufacturing programs were used to control machine tools in manufacturing.

Post-processors translate CAM data into a programming language known as G-code that CNC machines can read and operate accordingly. This advancement made the functioning of 5-Axis CNC machining easier, more efficient, and popular. This development was limited to the aerospace industry regarding multi-axis machines due to various complexities and their affordability to manufacturers in other industries. The high cost of computers and 5-Axis CNC machining hindered manufacturers from opting for the machine.

Subsequently, when the price of computers fell with increased demand during the 1960s, 5-Axis CNC machining started becoming affordable to all levels of manufacturers. CNC machining was listed as a controlled commodity by the US Department of Defense, citing its importance to national security. Only in 2009 was it allowed to be exported to precision machinery, subject to the condition that distributors and producers created features prohibiting machine tampering.

This, coupled with many other developments in post-processing systems, CAD, and CAM programs, improved automation, and production of high-quality projects, thus making 5-Axis CNC machining the most opted one. Eventually, the benefit of fast production, along with precision, repetition, and zero error, that the 5-Axis CNC machining could provide to the medical field was identified.

Since 5-Axis, CNC machining has been widely used in micromachining cardiovascular, orthopedic and other devices, implants, and machining surgical instrumentation. The quality and availability of equipment used in surgery and parts implanted in patients are key to the wellness and lives of patients and the reputation of doctors and medical institutions.

The 5-Axis Machining Process

The process of the 5-axis machining is what has made it extremely important, reliable, precise, and flawless, given that around 60% of CNC shop products require five-sided machining. As the name goes, the machine can move in “five” directions, unlike traditional tools that can only move along the X and Y axes. 5-Axis CNC machining has X, Y, Z, and A, B, C Axes.

                                                                             A 5-Axis CNC moves along its different axes in the following manner:

 

Axis

X-Axis
Y-Axis
Z-Axis
A-Axis
B-Axis
C-Axis

Movement

Left to Right
Front to Back
Up and Down
180° rotation around the X-axis
180° rotation around the Y-axis
180° rotation around the Z-axis

A 5-Axis machining has two main configurations:

Swivel-Rotate:

In this configuration, the head and spindle move around the table, which is horizontal, making it best for heavy parts and devices. Rotary Axes are used by rotating the spindle. B-Axis and C-Axis rotate around Y-Axis and Z-Axis, respectively, in this configuration.

Trunnion

These machines have moving tables and no spindle, making it beneficial for large volume machining. The rotation is more than 90° and is better for undercut capabilities. Here the A-Axis moves around the X-Axis, and the C-Axis rotates around the Z-Axis. Since there is no risk of collision, the spindle heads can be placed closer to the workpiece, unlike other multi-axis tools. This usage of a shorter cutting tool delivers impeccably finished projects at a faster rate.

Applications for 5-Axis CNC Machining in the Medical and Healthcare Industry

For manufacturing complex 3D-shaped devices and parts, 5-axis CNC machining is the best tool to opt for. The process meets the rigorous healthcare standards, which can be assured by the precision, repeatability, rate of production, and flawlessness of 5-axis CNC machining.

5-Axis CNC Machining is commonly used in manufacturing the following medical devices and parts:

Machined Surgical Instruments

High-grade surgical instruments that require faultless to ensure perfection and success in medical procedures can be manufactured using 5-axis CNC machining. These instruments are subject to safety requirements. A few such surgical instruments are:

  • Surgical scissors.
  • Blade handles.
  • Biopsy tubes. Cutters.
  • Saws.
  • Implant holders.
  • Forceps.
  • Plate benders.
  • Holders.
  • Clamps.
  • Spacers.

Micromachining

It manufactures extremely small and sophisticated medical parts used in drug-delivering technologies, implantable devices, exploratory surgical tools, etc. Manufacturing these requires a high level of expertise, because of which 5-axis CNC machining is the most suitable tool. The feature size of components goes up to 50 microns.

The following devices can be produced using micromachining:

  • Catheters.
  • Pacemaker components.
  • Stents.
  • Miniature screws for devices, implants.
  • Drug delivery systems.
  • Tubes.
  • Ophthalmic devices.

Electronic Medical Equipment

Unlike surgical instruments, which only have one or two metal components, certain complex equipment comprises or is even made out of several individual parts. Such complex equipment must be extremely precise to function without failure and can only be manufactured by 5-axis CNC machining. Some individually machined equipment parts include buttons, switches, levers, or bigger parts like monitor housings.

Electronic Medical Equipment that comprises thousands of smaller parts includes:

  • Heart Rate monitors.
  • X-Ray machine.
  • Ultrasound equipment.
  • MRI scanners.
  • CT scanners.
  • Diagnostic equipment.
  • Monitors.
  • Lighting.

Medical Implants

With 5-Axis CNC Machining, bodily implants can be manufactured that accurately imitate the structure and functioning of body parts and organs. Injection molding would be comparatively uneconomical to manufacturers due to the low and specific demand for implants. Hence, 5-Axis CNC machining ensures the implants’ personalization, durability, and performance.

The following is a list of common 5-axis CNC machined implants:

  • Knee implants.
  • Hip replacements.
  • Dental implants.
  • Spine implants.

Benefits of Utilizing 5-Axis CNC Machining in the Medical and Healthcare Industry

5-Axis CNC machining is one of the most advanced and sophisticated machining tools to manufacture medical devices and implants. The following are some important features of using 5-Axis CNC machining in the medical and healthcare industry:

1.Time and Cost Efficiency

5-Axis CNC machining has a higher speed of cutting less manual repositioning. Hence, reduces the time taken to finish projects. That means higher output in lesser time! This is advantageous to manufacturers to finish prototypes at reduced time and, more importantly, costs. This results in high-quality products reaching consumers at a faster pace than before and also lower prices.

2.Easy Set-up

A 5-Axis CNC machine uses a single set-up. This enables the machine to reduce time spent drilling holes, enhance efficiency, and reduce production time, costs, and errors.

3. Machining of Complex and Intricate Medical Parts

A more conventional method of producing complex and intricate parts is casting, which takes months to complete projects. With 5-Axis CNC machining, complex parts can be produced faster with greater precision.

Conclusion

Manufacturing medical devices and parts require high precision to comply with requisite standards. Coupled with the requirement of meeting cost and time efficiencies, there is no doubt that other machining processes do not stand a chance in delivering the same. To sum up, 5-Axis CNC Machining is the most effective and compatible tool when the machines’ time, expenses, precision of production, and longevity are considered.