UNISIG ’ s Approach to Automating Surgical Instrument Manufacturing
MACHINING & MACHINERY
THE UNE6-2I
UNISIG
UNISIG ’ s Approach to Automating Surgical Instrument Manufacturing
As surgical instrument manufacturers pursue greater throughput while facing increased labor costs , automating the medical instrument manufacturing process has become a necessity . However , integrating automation into the gundrilling process for drilling deep holes in extremely precise surgical instruments in lights-out operation is a major engineering challenge requiring more than simply pairing a robot with a deep-hole drilling machine .
The right machine , tools and process must all come together to create small holes with extreme precision in difficultto-machine materials such as titanium and surgical stainless steel . More importantly , the entire system must flow from a unified concept where the whole is greater than the sum of its parts .
To meet these challenges , UNISIG developed its UNE6-2i-750-CR dual independent spindle gundrilling machine . The UNE6-2i is capable of gundrilling hole diameters ranging from 0.8 – 6 mm in part lengths measuring up to 30 inches with depth-to-diameter ratios from 20:1 to more than 100:1 . The machine has a maximum combined drilling speed of 28,000 rpm and a 3,000 psi ( 207 ) bar programmable flow-based coolant system with dedicated pumps for each spindle to ensure precise coolant pressure control .
Automating hundreds of cycles of precision manufacturing , however , is not possible unless the overall operation is considered from the outset . Surgical instrument manufacturing is a sequential process : parts must be loaded into the machine in a particular way for specific operations that happen in a specific order .
Workpiece length , shape and configuration determine where it is gripped by the robot when loaded into a machine , moved from spindle to spindle for drilling , residual cutting fluid removed , and returned to the pallet . Where a part is gripped impacts where it is clamped for drilling to ensure accuracy . Every variable along the process chain must be considered and accounted for , and the calculus is detailed and complicated .
Then there are unique customer needs and requirements . The equipment and process must accommodate a variety of part families and hundreds of parts to increase runtime and efficiency . Operators must be able to change over part types and programming without calling in an automation specialist , and the entire process must be controlled from a central interface . Add to the mix that everything must be packaged in as small a footprint as possible , and the scope of the engineering challenge comes into focus .
UNISIG ’ s approach to solving these problems , however , results in targeted automation that enhances the existing benefits of gundrilling , ensuring a solid foundation for reliable process-wide automation .
At its core , the automated UNE6-2i is a purpose-built machine with automation embedded in its design , not added as an afterthought . Flexibility and adaptability are maximized by a harmonious , interdependent mechanical , software and operational planning scheme .
To meet size constraints , a 6-axis robot was embedded in the machine with a pallet system on the backside of the machine , allowing easy operator access from the front to setup the machine without compromising ergonomics . The configuration enables quick setup changes between prototype and proving operations and full production runs .
The robot automatically repositions the workpiece from the front of the first spindle into the rear of the second spindle without operator input . The process of drilling a part from both ends in a single-piece flow is unique to UNISIG . Workpieces with enlarged features on one side are loaded from the rear of the collet , solving a common problem in gundrilling medical surgical instruments with full automation .
Control of the UNE6-2i and a computer are consolidated into the Human Machine Interface ( HMI ), a menu-driven touch screen system for easy , intuitive operation . Training and operator engagement with the system is significantly reduced due to user-friendly UNISIG controller menus and prompts .
UNISIG ’ s comprehensive and integrated approach to automating medical part manufacturing is a vison that sets it apart in the industry . It ’ s more than drilling the impossible hole . It ’ s a commitment to understanding and to the research that drives continuous improvement and innovation for automated part production at its full potential .
Further information on all machines and the complete UNISIG machine program is available at : www . unisig . com or follow the company on LinkedIn and Twitter (@ UNISIG ).
You will also meet us at the EMO 2023 show in Hannover , Germany , from 18 – 23 September .
For further information , please visit www . unisig . com
92 PECM Issue 62