The UR robots handle highly sensitive glass tubes in a precise pick-and-place application. Their use stabilizes the production processes, improves the quality of the glass components and simplifies the work processes of the employees. Hofmann was able to increase its efficiency and production capacity in the application area by 50 percent. "The constant shortage of skilled workers has given us quite a hard time in recent years and has made us realize how important it is to fully utilize the potential of our existing employees. This gave us the idea of automating repetitive tasks such as machine loading. With the robots from Universal Robots, we have found an ideal solution for this," explains Robert Hofmann, Managing Director of Hofmann Glastechnik.

Unlike conventional industrial robots, the collaborative UR robots can work directly next to humans with no or minimal protective housing once a risk assessment has been successfully completed. This creates new opportunities for the automation of a wide range of processes, especially for small and medium-sized companies like Hofmann. Two UR robots are now in use here in the fully automated series production of glass cuvettes. The UR5 and UR10 robot arms, which are named after their payloads in kilograms, independently load the machines. In a precise pick-and-place process, the robot picks up highly sensitive glass tubes, feeds them to a PLC-controlled glass lathe, removes them from the lathe after processing and sets them down again.

Glass as a material brings with it very special requirements in the forming process. Robert Hofmann knows the challenges: "The glass is extremely sensitive. Even the smallest temperature changes on the tools have an effect on the forming result." The production process must therefore be precise and stable for each part in order to achieve consistent quality of the glass components. To achieve this, the temperature on the machines must be as constant as possible. In the past, employees loaded the glass lathes manually. Even short interruptions in the work process caused the machines to cool down again and again. However, the first time the UR robots were used for this task, the results were excellent. "The quality of our glass components has improved enormously thanks to Universal Robots," confirms Robert Hofmann.

The UR robots perform tasks that require maximum precision with consistent accuracy. At Hofmann, they load the machines for up to eleven hours a day. Cycle times are adhered to and downtimes are reduced. Depending on the application, the UR robots at Hofmann now produce between 200 and 400 glass cuvettes a day. If required, the company can use the collaborating colleagues flexibly on different glass lathes. "It is very easy to 'redock' the robots. We have developed a device that allows us to easily move the UR robots between the different machines," explains Björn Uthe, Head of Machinery at Hofmann. Once such a changeover has taken place, the robot is immediately ready for operation.

Handling the UR devices is intuitive. The required movement sequences can be defined using touchscreen tablets. In "free-running mode", the user can simply grab the robot's arm and teach it new tasks by physically guiding it from waypoint to waypoint.

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