As a result of increasing quality requirements, edge rounding, descaling and deburring are becoming increasingly important in sheet metal processing. In light of this, one supplier in the sheet metal processing sector invested in new system technology.
With around 330 employees working in 3 shifts, KUIPERS technologies GmbH in Meppen produces parts and components for, among other things, the regenerative energies sector, trailers, general mechanical engineering or shop fitting. In four generations, the company has developed from a workshop to a high-tech company in the sheet metal processing sector.
The company relies on high quality standards. So the machine fleet is always geared toward the markets’ requirements. Now, KUIPERS technologies has invested in an SBM-XS 300 from LISSMAC, a system for two-sided deburring and even edge rounding of punched and laser-cut workpieces in a single process.
The coating adhesion and the resulting corrosion protection are important quality criteria for customers and surface finishers. That is why the investment in custom-fit system technology was inevitable. Managing Director, Michael Kuipers has been with the company for 15 years. He describes the decision-making process: “Originally, we thought a universal machine and the wet-grinding process were the right solution for any and every part. We had been using a system like that for several years, but the work results were not ideal. So, we started looking for a system that met our requirements.” There were corrosion problems, especially with respect to steel grinding. There were fluid residues on the parts. And the maintenance expenses for wet-grinders were significantly higher, according to KUIPERS. In addition, the new deburring machine was to ensure the processed items ran through the system faster, so customer deadlines could be met on short notice. While the previous system is now used to process aluminium and stainless steel, with the new LISSMAC system, KUIPERS is able to deburr or round both sides of a component parallel to production. As a result of the new investment, the processes have now been improved and supplemented, while keeping the various materials to be processed in mind. In addition, this allows for improved process control with respect to logistics.
Work parallel to production due to automation
The LISSMAC SBM-XS 300 is very compact machine that can work on both sides. When processing small parts, it ensures fast throughput and a high level of flexibility when processing. The standard design is a stand-alone system. Since the parts are to be processed parallel to production at KUIPERS, the system was automated. “Processing parts parallel to production doesn’t work in systems with very short throughput times. There’s also the fact that a highly qualified specialist shouldn’t just put parts on a conveyor every 10 seconds. So the system had to be automated, which everyone understood and in a way that the sequence fits into the processes,” explains Michael Kuipers.
Two employees from the robot team, which KUIPERS founded about three years ago and which works in cooperation with the University of Osnabrück, worked on this project for about 2 years. The result: The robot autonomously recognises the components to be processed, takes them from the pallet and places them on the inlet conveyor belt. After they are processed by the LISSMAC SBM-XS 300, it takes the processed components from the outlet conveyor belt and palletises them on another pallet. At the same time, the robot loads new components onto the supply conveyor belt. When there are no further components to process, the robot switches to clearing mode and palletises the remaining, already processed components. Looking back, Kuipers says: “The development and implementation of the automation was one of the major challenges because the cycle time changes two to three times during the process.”
Due to the automation, the machine can now work continuously in three-shift mode. If needed, it can still operate as a stand-alone.
The process is also very simply set up for the system operator because it is relieved as a result of many otherwise necessary settings being automated. The work order can therefore be completed quickly and so it is reliable for the process.
Requirement for good coating surface adhesion
A technical problem that had to be solved with the new LISSMAC system is the coating adhesion on components that would later be coated. The edge alignment results in the workpieces not being adequately coated in the area of the cutting edge. This can prevent the intended protection particularly when applying corrosion protecting coatings. Another requirement that is becoming increasingly important to coaters is an oxide and burr-free cutting edge. However, when using oxygen lasers, the cutting gas creates an oxide layer on the cutting edge. Because of the pretreatment, the coaters cannot ensure that this oxide layer will be completely removed. To avoid this problem, sheet metal cutters work with nitrogen as a process gas. This results in the development of (micro) burrs on the workpieces. How big this burr is ultimately depends on the material thickness. What is clear, however, is that the edges from a laser cut are very sharp. To achieve better coatability or coating adhesion, KUIPERS is therefore betting on rounding.
Wilhelm Kuipers stepped into his father’s metal construction company 40 years ago, founded the sheet metal processing workshop 30 years ago and was the managing shareholder for 27 years until he passed the company on to his son and the 4th generation, Michael Kuipers, 3 years ago. Today, he advises the company and underscores the significance of the topic: “We have to meet the increased requirements with respect to the surface of the parts with our processes. These are corrosion protection, injury prevention and the appearance in general.”
Ensuring efficiency and quality for the customers
Karsten Hanenkamp has been with the company for 10 years. As the operations manager, he is responsible for all production departments and knows the requirements for new system technology. “We have to ensure efficient and process-reliable production procedures and ultimately work efficiently,” he said.
Wilhelm Kuipers underscores that: “Of course the topic of cost efficiency is the focus. Automation, however, results in the development of new business segments and ensures production in Germany. With the new SBM-XS 300 from LISSMAC appears to have succeeded. In Michael Kuiper’s opinion, the technology has proven itself with respect to all components that fit in the machine. In addition, after being processed with the LISSMAC system, any surface coating, for instance, a KTL coating, wet varnish, a powder coating or galvanisation can be applied, with varying thicknesses. “By rounding the edges, we largely solved the coating adhesion problem. By rounding the cutting edges, the coating adheres to the components better. In addition, our customers value the durability of the components,” says Michael Kuipers.
This much is certain: Rounding is an additional work process and a conscious investment in defined quality. The feel of rounded parts is significantly better as thus, so is the quality of the parts. Accordingly, KUIPER’s customers increasingly order rounded parts for specific applications.
A reliable partner and stable values
LISSMAC and KUIPERS have cooperated substantively for many years. For instance, there was an lively exchange at the VdLB (Verband deutscher Laseranwender-Blechbearbeitung e.V. (Association of German Laser Users in Sheet Metal Processing)) regarding a variety of sheet metal-related matters. Since the LISSMAC system was operated manually in the beginning, they mutually came to the idea of automating. That was then implemented within a year. “It went hand-in-hand. While LISSMAC provided the interfaces, the automation was completely developed by KUIPERS technologies,” says Dirk Schürstedt, Head of Regional Metal Processing Sales at LISSMAC Maschinenbau GmbH, looking back.
So, as the machine manufacturer, LISSMAC, relies on stable values, the component manufacturer, KUIPERS technologies, does too. “The process chain always starts with a good consultation. We flank every one of our orders with a good consultation. We intend to continue doing that in the future,” says Wilhelm Kuipers. Michael Kuipers defines the future objectives: “In the future, the focus will be on the assemblies and our own product. Of course the topic of digitalisation and networking the systems at KUIPERS is already being discussed in the background.”
Text author: Annedore
Bose-Munde, specialised journalist for technology and economics
Images: KUIPERS technology