Never before has there been a greater need for a responsive, flexible and efficient medical manufacturing sector. And as many companies across the globe reconsider, and perhaps also re-configure their machining capacities, the demand increases for machines with more flexibility.
Starrag’s Bumotec multi-axis machining centres enjoy a renowned status in the efficient one-hit manufacture of even the most complex medical components and the Bumotec s191 and s181 models in particular are capable of single set-up drilling and tapping, turning and milling.
While engineers at the University of Sheffield Advanced Manufacturing Research Centre (AMRC) have actively demonstrated the micro-machining capabilities of their s191, ‘to show our partners and wider industry what is achievable when working to an accuracy of 0.001mm on workpieces as small as 1.5mm,’ Bumotec machines have an established track record in medical machining by producing components such as surgical hooks on the s181. This machine produces a finished component from 25mm titanium bar in under 14 minutes compared with 20 minutes for single-station machining.
In another example, a Bumotec s191H is machining surgical cutting tips including titanium types in a single set-up and to very high accuracies. The precision-engineered tips – the critical ‘working end’ of power tools that use ultrasonic vibration to cut the bone and with no risk of damage to soft tissues – feature ‘teeth’ with helical tips that must be machined to within 10 microns.
A host of other medical components are also being successfully machined on Bumotec machines, including titanium hip joints – turning and milling the cone to two and four microns, respectively, in the same set-up compared to the previous process of using separate machines – and producing stainless steel hip stem rasps from bar.
Starrag UK’s latest Bumotec multi-axis machining centre, the 191neo is also making its mark, as demonstrated by Galway-based precision engineering specialist Dawnlough Ltd. It is using the machine to create a more stable and efficient process for robotic surgical application parts.
The company is an effective one-stop manufacturing service to a myriad of medical device and aerospace companies through Ireland and further afield.
Dawnlough saw the machine producing lumbar interbody fusion cages for spinal fixation, from a 40mm diameter polyether ether ketone (PEEK) bar, utilising up to 15 tools in a single set-up, including finishing the component. The ability of the nine-axis Bumotec 191neo to manufacture complex parts in a single set-up was why the company became the first in Ireland to install the machine, as Managing Director Brian McKeon, explains: “Compared to our existing 5-axis machining route on particular processes such as components for robotic surgical applications, we recognised how the Bumotec’s multi-axis, high-accuracy capabilities would enable us to create a more stable and more efficient process.“
The Bumotec 191neo can accommodate bars of 42mm, 50mm and 65mm, and has 50m/min traverse rates for its X, Y and Z-axes travels of 410mm, 200mm and 400mm. In addition to milling and turning routines, the 191neo can also be used for grinding, polishing, skiving, gear hobbing and diamond cutting with no set-up or fixture changes.
Available in four options – P model with vice, PRM with multi-purpose pick-up vice, R with back-working spindle and RP version with combined vice and back-working spindle – the 191neo is effectively available in 12 versions.
The machine is extremely stable during production and with a 90-position tool magazine that operates in parallel with integrated tool breakage probing, plus a pallet system and, being configured for a robotic, modular or custom-made automated cell, users have access to 24/7 production regimes. Other options include temperature-controlled, high-pressure chip conveyor and bar loading.
