Robots in action can be found everywhere. Robot Manufacturers give examples of robot applications in different industries.
KUKA Roboter, Germany - IFR Partner
Utmost precision for plastic components
It's all about plastics processing at Borscheid+Wenig GmbH, whether it's foamed material or plastic - or a combination of the two. The Bavarian-based high-tech company offers a comprehensive range of products that few others can match: from the manufacture of individual components to complete assemblies, this globally operating industrial firm is committed to the highest quality standards. The use of KUKA robots has enabled the 300-strong company, which is based in Diedorf near Augsburg, to boost productivity.
Borscheid+Wenig GmbH has had rubber processing in its production line ever since it was founded in 1961. Since 1985, the Diedorf-based company has also been active in the injection molding of plastic parts for large-scale industry, starting with components for refrigerators and washing machines for the domestic appliance and electrical goods industry, and later as an automotive supplier. Today, Borscheid+Wenig GmbH operates a total of 40 Sumitomo DEMAG injection molding machines. "Up to 2009, we used only linear robots in our production processes. With growing order volumes, greater component diversity and higher process complexity, it was the right time to convert some of our systems to industrial robots," explains Carlo Wenig, Chief Technical Officer at Borscheid+Wenig GmbH. Today, nine systems are equipped with jointed-arm robots from KUKA. "In KUKA system partner SAR Elektronic GmbH from Gunzenhausen we have a reliable partner who has guided and supported us through the project phases," Carlo Wenig continues.
The new plastic components for Porsche and Volkswagen off-road vehicles were even more demanding to manufacture, being strongly three-dimensional and having a much larger number of variants than the predecessor models. These challenges were the deciding factor for the company management to give the go-ahead for the first jointed-arm robots for injection molding machines in 2009. "A manual solution would no longer have been feasible," explains Johannes Spatz, Operations Engineer at Borscheid+Wenig. The process in the first system begins with two bushings being loaded into the injection mold and the rapid removal of the product directly by the ejectors. The KUKA shelf-mounted robot of type KR 60 L30-4 KS Speed then moves with pin-point accuracy with the component in its removal gripper to the stationary periphery devices and adds up to eight pins to the product. During the next step, a sheet-metal snap nut is inserted - provided that the component passes a 100% quality check. Finally, the component is set down on a conveyor system, and the process starts again.
The increased product quantities were also no longer manageable using a linear robot. "Without automation, we would have been able to produce considerably fewer components last year," Johannes Spatz clarifies. KUKA robots are in operation in the two-component process in particular. "Significantly reduced mold open times, extremely high positioning accuracy and stiffness during transfer from cavity 1 to cavity 2, and a powerful and flowing demolding motion inside the injection mold," lists Carlo Wenig as reasons for the conversion. "Compared with the existing linear systems, there are much fewer system faults, the set-up times can be minimized, no maintenance intervals need to be observed, and there is less wear on the mold. Furthermore, the reject rate has gone down dramatically," Carlo Wenig continues. In addition to the shelf-mounted robots with their optimized weight, reach and speed, Borscheid+Wenig utilizes standardized KUKA options such as the fluids/energy unit. This is mounted on axis 3 and is responsible for the electrical and pneumatic signal exchange on the gripper. Compared to a linear robot, the shelf-mounted robots from KUKA have a much smaller footprint and can be installed in shops with very low ceilings.
Due to the wide range of components being manufactured, it is necessary to change regularly between different grippers. "It is extremely difficult to meet these requirements with the limited Cartesian motion of a linear robot," explains Christian Müller, Head of Injection Molding Technology at Borscheid+Wenig GmbH. "The set-up costs would be enormous - the operator would have to change the gripper manually on the linear robot."
KUKA system partner SAR supplements the jointed-arm robots with the complete peripheral system and the grippers, which are deposited in a gripper changing station when not in use. Here, the six-axis robot sets down the gripper that is no longer needed and uses the coding to select the required gripper from up to six different grippers. "Our workers showed great initiative with the new machines right from the start, and have already acquired the relevant know-how for gripper maintenance and construction," Johannes Spatz says with pride.
Following the first positive experiences with the automation of the 650 t injection molding machine with medium clamping force, Borscheid+Wenig GmbH decided to automate a small machine with a two-component process (soft and hard) with a clamping force of only 150 t using a six-axis robot. A small shelf-mounted robot of type KR 6 KS was implemented in a new system. The process involves the insertion of two metal rings, which need to be positioned and transferred freely in space at an angle and with pin-point accuracy.
Injection molding plants today face tough global competition. Borscheid+Wenig GmbH will continue to rely on KUKA robots: a new project is already at the planning stage. Three more shelf-mounted robots have been ordered from system partner SAR GmbH, with start-up planned before the end of the first half of 2011. "A complex plastic component is to be produced in large quantities and in a range of variants. Once again, we have opted for KUKA robots. Without the flexibility of the KUKA robot, the realization of the project would not be viable - either economically or in terms of quality," asserts Christian Müller.
By the end of 2011, nearly all the skilled workers at Borscheid+Wenig will have received training for the systems. Carlo Wenig is convinced: "It is our goal to employ only the best workers. The same goes for our robots. At KUKA Roboter we have colleagues who contribute to value creation - the facts and figures speak volumes."