As is common with automotive and aerospace industry OEMs, medical OEMs want their suppliers to produce more than just pieces or parts. In addi- tion to supplying a medical device or instrument, today’s medical shops are being asked to produce the complete assemblies or kits associated with those instruments or devices. Along with those assemblies and kits are any required sterilized containers or packaging. What this means for medical shops is
that they must process a wider range of part materials that extends well beyond just metals. Te real challenge is to do so cost effectively for materials such as foam, fiberglass, plastic and rubber. So, those medical shops that have histori- cally used only conventional metalcut- ting machines are now incorporating abrasive waterjet cutting. And as a re- sult, the technology is quickly becoming much more commonplace and readily accepted within the medical industry. Abrasive waterjet machines give
medical shops much needed versatility in terms of both part processing and materials. As opposed to adding special machines for each material, shops can quickly and cost-effectively process practically any material used in medical kits and packaging with one abrasive waterjet machine. Abrasive waterjet machines are
also able to produce high volumes of near-net-shape components. Abrasive waterjet machines, especially those with large table sizes, allow medical shops to rough cut hundreds of near- net-shaped parts from multiple sheets of material in one machine setup. But most importantly, they do this faster
and more cost-effectively than conven- tional machining methods. When medical parts are processed
in this fashion, less material is wasted and part cycle times are significantly shortened. Large amounts of expensive materials such as titanium are no longer turned into chips as part of conventional machining processes. Te minimal amount of scrap from abrasive waterjet cutting is in the form of solid “drops” that is a much more valuable form of scrap than chips.
When medical parts are processed in this fashion, less material is wasted and part cycle times are shortened.
When abrasive waterjets are incor-
porated into the medical manufacturing process to produce near-net-shaped parts, conventional machining centers are typically only used for finishing, thus shortening the overall machining time. Tis results in less wear and tear on those machines due to aggressive rough-cutting operations. Cutting tool costs are also reduced as fewer tools are used, and those that are used last longer. Additionally, conventional machine tool capacity is freed up for other work. Te increased accuracies and en-
hanced piercing capabilities of abrasive waterjet machines further contribute to their increased use within the medical sector. Today’s machines can hold toler- ances to around 0.001" (0.003 mm) and generate practically taper-free cuts. Tey can efficiently pierce composites, lami- nates and other such materials without damaging material surfaces or integrity.
Julie Kaiser
Regional Manager OMAX Corp. Kent, WA
Abrasive waterjet machines currently
available also provide several advanced ac- cessories and functions that are especially appealing to medical shops. Some of these accessories include taper compensating heads for the straightest cuts possible and systems that automatically adjust nozzle heights to compensate for changes in part material thicknesses or irregular surfaces. Abrasive waterjet machine functions
that prove valuable to medical shops include nesting soſtware and stack-height calculators, both of which help increase machine output. Nesting soſtware allows shops to cut the most parts as possible out of every sheet of material. Te cal- culators indicate the maximum number of sheets that can be stacked and cut simultaneously without compromising individual part accuracy. Another relatively new abrasive water-
jet technology of interest in medical shops is six-axis 3D part cutting on machines equipped with rotary axis units. Many industry experts believe that this capability will drive abrasive waterjet cutting further into the medical machining sector. While most medical shops use
abrasive waterjet to manufacture instru- ments/devices and their components, there are a few innovative shops using the technology to process medical im- plants. For these shops, abrasive waterjet machines cut implantable parts—espe- cially very thin ones—without warping them or affecting their surfaces or base materials during the process. As medical shops are forced to pro-
cess more parts and work with a wider variety of materials, the potential for abrasive waterjet cutting in medical ap- plications will continue to grow.