Saving time and healing bones
hg medical | Contract Manufacturing | Medical engineers take things very seriously
To ensure the timely delivery and top quality of orthopaedic implants, hg medical relies on nearly two dozen HERMLE 5-axis machining centres. The contract manufacturer recently ventured into the world of robot automation for the first time and stands to gain from numerous benefits..
Florian Lukats can tell when it is winter just by looking at the order books. He manages the milling shop at hg medical in Raisting, a municipality at the southern end of Ammersee lake in Germany. The contract manufacturer specialises in meeting the unique needs of its customers in the medical sector. Demand increases during the winter for the products manufactured in three-shift operation: Orthopaedic implants for osteosynthesis. The small plates – usually made of titanium, sometimes stainless steel – help stabilise bone fractures and allow the bone to grow together naturally in a shorter space of time.
The company was launched in 2007 with two milling machines, two lathes and two employees. Today, roughly 190 people are employed in Raisting alone. The second plant in the USA, founded in 2015, currently employs around 40 workers. The machinery and equipment have also continued to grow: “We have 19 HERMLE machining centres installed in Germany and four in the USA, with a further five planned for the plant in Raisting. Moreover, we are currently constructing another plant in the USA, which will be identical to this one in terms of capacity,” explains Lukats. hg medical’s strong ties to the United States can be traced back to its origins as the European distribution centre for a leading US supplier of orthopaedic aids and shoes. “Even today, around 90 per cent of our customers are based in the USA,” adds Lukats.
The only problem with growing so successfully is that you soon run out of space. This is also visible at the company’s Upper Bavarian German site. At first, the turning shop, the milling shop and the analysis team were all located in one building, where the entire second process also took place: From surface treatment to quality control and packaging. When things became too cramped, the company built a new facility adjacent to the existing one and relocated the milling shop. Further growth necessitated the construction of a third building. "As such, the location has a bit of a rambling plan,” explains Lukats and continues: “And we are nowhere near the end of our expansion road map. It is just that we have run out of capacity here in Raisting. And that is why the focus is now on the USA.”
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From left: Stefan Bux from HPV HERMLE Vertriebs GmbH and Florian Lukats from hg medical GmbH -
A building full of HERMLE: hg medical places its trust in the precision and swift service commitments offered by the Gosheim-based machine manufacturer. -
Orthopaedic implants fixate bone fragments and allow the fracture to heal faster. -
Thanks to robots, hg medical can mill implants in just one pass. -
Head of department Florian Lukats (right) with CNC machine operator Max Schade. -
The robot gripper is crafted entirely from stainless steel, as the use of aluminium would contaminate the medical implants
To ensure no harm is done
The location of the customer is irrelevant when considering the stringent requirements placed on the contract manufacturer’s products, as regulatory authorities such as the FDA (Food and Drug Administration) maintain strict standards universally. Tolerances, surface quality and overall quality must always meet the highest standards. “This starts with visual quality, extends to dimensional accuracy and ends with the documentation,” explains Lukats. It is also important that the coolant is suitable and that the lubrication greases, oils and lubricants are approved by pharmaceutical authorities. After the entire machining process, there must be no residues remaining on the implant that could harm the human body. “When it comes to machining tolerances, we work within a range of a few hundredths of a millimetre," says Lukats, highlighting a requirement that ultimately led hg medical to HERMLE.
“HERMLE delivers the quality, precision and accuracy that we need. Especially for the 5-axis simultaneous machining of free-form implants,” notes Lukats, when explaining the crucial role that HERMLE machines play at the headquarters. They occupy an entire building and are each allocated a unique number for clear identification; organised but not sorted. This has to do with the documentation obligation and organic growth: Each 5-axis machining centre is certified, which is why hg medical is unable to change the internal machine designations. And they cannot be moved either due to the limited amount of space available.
First robot in operation
Four additional HERMLE C 12 U RS 05 machining centres have been installed in the milling shop since the beginning of 2023. hg medical previously automated all of its machines with the IH handling system. The four new systems are the first to be equipped with robots. They insert blanks into the chuck, clamp the semi-finished part and remove the finished milled implant. At the other systems, a workpiece changer supplies the milling centres with pre-loaded material, thus enabling unmanned automatic operation. “We have lots of small-scale series. The investment plan for the RS 05 systems was finalised following an order from a customer for significantly larger quantities of their products. We wanted to be faster and to reduce labour costs,” reports Lukats. How? By introducing robot-assisted milling centres to handle a work step that was up to now only possible manually.
“We previously milled the implants in one clamping setup. This left us with two support rods that had to be removed and their remnants ground down manually,” explains Lukats. To enable the C 12 U to mill away the small protrusion, a second clamping device and a gripper are required to move the component. The special feature: To work extremely precisely, the image is the negative of the bone plate. “After the initial milling process, the gripper takes hold of the semi-finished implant and places it within the negative die. Positional holes ensure precise placement, allowing the machine to process the surface with the same precision as in the initial clamping.” The plate is ready for surface treatment and quality inspection after 19 to 25 minutes.
Three times the benefit
“We have high expectations when it comes to robot automation: It should save time and effort while maintaining or even improving overall quality. And HERMLE achieved these goals,” explains Lukats. hg medical has eliminated the need for manual grinding, which always posed a risk of errors. Further, the company has also optimised the preparatory phase. Instead of pre-stamping the blanks and clamping them in vices, as required by other automation systems, the operator simply pushes a die with the titanium or stainless-steel plates into the robot cell.
When concluding, Lukats additionally highlights another distinct advantage of HERMLE robots: “Modern high-tech machines inspire people. The new technology is a motivational boost for our employees and helps fuel our growth.”
