Heinrich Georg Maschinenfabrik recently commissioned a hybrid cut-to-length line with trimming shear for aluminum, stainless steel and steel sheets at the Alfun “Metal Service Center” in Bruntál, Czech Republic. With a high degree of automation and a multitude of design details, the plants achieve high productivity.
Alfun Metal Service Center, established in 1999, supplies a wide range of flat and long products made of aluminum, stainless steel, steel and copper. One focus is on sheet metal for the automotive industry, which meets the highest surface quality requirements. The company also produces stainless steel sheets for “white goods”, for example laundry drums, where precision-cut edges and exact adherence to the squareness of the individual sheets are essential.
Since 2015, Alfun has been operating a cut-to-length line from Georg for strips with a thickness between 0.3 and 3.0 mm and a width of up to 2,000 mm. It cuts sheets with a length of up to 6,000 mm.
Due to the steady increase in incoming orders, the production volume had to be increased. To achieve maximum flexibility in productivity, a new hybrid line was to both trim and cut-to-length strips of steel and aluminum.
An important criterion in the decision for a new system was the quality of the cut edges, because many of the finished sheets are welded with lasers at Alfun’s customers.
High degree of automation ensures quality and productivity
Due to the good experience with the first plant and its longevity, Alfun’s management has also decided to use Georg for the second plant. It is designed for maximum performance: The highly automated line trims and slits aluminum strip with a width of up to 2,300 mm and stainless steel strip with a width of 2,050 mm at a speed of up to 60m/min.
In contrast to the first system supplied by Georg, the new one has a turnstile for coils with four positions. It increases the flexibility of production, because rings do not have to be processed exactly in the order in which they are delivered.
Threading up to the straightener is automatic; it relieves the operators and saves time. The barcodes attached to the delivered coils are scanned and merged with the order data, whereupon the process control system automatically sets the parameters for the downstream system components up to the stacker. An example is the knife gap, the width of which depends on the material strength, thickness and width of the strip.
Since the plant processes aluminum as well as steel and stainless steel, Georg supplied three straightening cassettes for the high-performance straightening machine, which are adapted to the material values and surface properties of the respective material. The cassettes are changed fully automatically at the touch of a button within a few minutes.
The hem scrap cutter is equipped with “Georg Shimless Tooling” technology. It eliminates the need to insert shims when reassembling ground-off blades and significantly reduces downtime when changing blades.
In order to achieve the highest cutting quality during cross-cutting, Georg has supplied a continuous cutting eccentric shear. Its blade has an adapted contour that ensures high precision especially when cutting highly sensitive stainless steel.
At the outlet of the line, sheets up to 6,000 mm long can be stacked on one stacking station or sheets up to 3,000 mm long can be stacked on two pallets. The changeover can be carried out on the fly at full line speed without interruption and without new adjustment. This not only reduces unproductive downtime: In addition, there are no marks or run-off marks on the strip in the straightening machine that could cause a stoppage … an important aspect especially for stainless steel with a high-gloss surface.
The balance after one and a half years
After extensive training of the employees at the Georg Akademie in Kreuztal, the new plant went into operation in summer 2019. Since the intuitive operator guidance of the new plant is very similar to that of the existing one, the operators were quickly familiar with the operation.
Since commissioning, the plant has been operating permanently in two shifts, with the exception of the Christmas vacations. So far, there have been no production stoppages caused by the plant.
All project goals have been achieved: the new plant operates precisely and achieves the targeted high productivity, which is reflected, among other things, in low operating costs. With the combination of “excellent straightening” and “very good cutting”, Alfun supplies sheets that fully meet customer expectations in terms of dimensional accuracy, quality of cut edges and surfaces.
Extensive automation has significantly increased productivity compared to the other equipment present in the plant. Based on the order data, the process control automatically adjusts the parameters of the entire plant to the requirements of the respective material. This also helps to ensure that the quality of the delivered sheets is reproducibly high day in, day out – regardless of the particular shift.
The automatic knife clamping of the eccentric shear has also proven its worth: At the push of a button, the knife bar assumes a change position. The knife is changed in a few simple steps without having to loosen tension or pressure screws or disassemble other components. After less than ten minutes, the plant resumes production. In the past, this process had caused a shutdown of half a shift at comparable plants.
The integration of the vacuum stacker into the process control system contributes significantly to the low energy requirements of the plant: Based on the thickness, width and length of the sheets as well as the material properties, the process control system calculates which vacuum is required for the pickup. This ensures that each sheet is only lifted with the vacuum required for safe lifting and is transported extremely gently, but that too much energy is not expended due to excessive suction forces. Since the hydraulic unit does not always operate at full power and is also enclosed, noise emissions are low.
The high productivity of the plant can be concretely quantified, among other things, with the personnel deployment: Compared to the first system supplied by Georg, the new Georg system can do without about 20 percent of the operator capacity.
With the new plant, Alfun is also well positioned for the future to meet the increasing demands of its customers and to develop further market segments. For example, the space for a surface inspection system, electrostatic oiling machine and other foiling stations is already provided.
About Heinrich Georg Maschinenfabrik
Georg is a specialist for sophisticated and economical solutions in coil processing and machine tool manufacturing that combine classic mechanical engineering with process optimization and service solutions. The advanced strip processing lines, the world-leading production lines for the transformer industry, and the modern machine tools for roll and turbine machining are in use in renowned companies worldwide. They make an important contribution to process optimization and thus to the economic success of customers. The highly automated product range is complemented by a range of consulting, planning and services, and is used for sophisticated and standardized applications. The third-generation family-owned company with over 500 employees and worldwide sales and service offices serves the energy, mobility and industrial markets in particular. Georg stands for responsible action and focuses on resource conservation and energy efficiency.