In line with a capacity expansion, the fettling shop of the MMG Marsberger Metallguss Gebr. Cordt oHG was completely revamped to meet requirements for more capacity as well as improved quality and better ergonomics. For this purpose the company invested in a new wire mesh belt blast machine, the modernization of the existing shot blast equipment, two new dust collectors and a blast cabinet, all supplied by Rösler.
Since the Marsberger Metallgießerei Erger was taken over by the brothers Olaf und Oliver Cordt in 1996, the facility has undergone significant expansion. Today the equipment and services of this company include several lines for sand casting of different aluminum alloys, gravity die-casting and machining of these components on ultra modern machining centers and lathes.
A complete package for the blast cleaning operation
In 2018, in order to upgrade the blast cleaning operation to meet today’s requirements, the company decided to purchase a new shot blast machine, as well as modernize their existing shot blasting system. In addition, two new dust collectors and a manual blast cabinet were purchased. Thanks to the modern design, high quality equipment, comprehensive after sales service and the possibility to source everything from one single source, the customer decided to do this challenging project with Rösler. Another reason to go with the supplier from Untermerzbach was a referral from another foundry that had an excellent experience with similar Rösler equipment.
Wire mesh belt blast machine meets all demands for quality, performance and ergonomics
The new de-molding blast system had not only to fulfill the challenging customer demands for blast cleaning quality, throughput and uptime, but it also had to be easy to handle by the operating staff. In line with these requirements Rösler developed a foundry version of the wire mesh belt blast machine RDGE 1250-4-F with a split elevator to fit the machine into a building with a ceiling height of 5 m. Special attention was paid to optimized wear protection. For example, the blast chamber is completely made from manganese steel and lined with easy to exchange cast wear plates from highly wear resistant material. The wire mesh belt, also made from wear resistant material, is designed for loads of 250 kg per running meter.
Four Gamma 400 G turbines, optimally placed around the blast chamber and with a drive power of 15 kW each, ensure that even extremely complex castings are perfectly blast cleaned. Compared to conventional blast wheels these high performance Rösler blast turbines, equipped with curved throwing blades in Y-design, generate an up to 20% higher blast performance while also maintaining a lower energy consumption. Their unique design allows for the full use of both sides of the throwing blades. And due to the clever quick-change system a blade change can be performed very quickly without having to disassemble the turbine. This practically doubles the service life of the throwing blades. The wear resistant and energy saving Gamma 400 G turbines were also used for the modernization of the existing shot blast system.
The new blast machine is equipped with a work piece recognition system making sure that the blast turbines are only throwing media, when work pieces are passing through the machine. With no work pieces present the machine automatically goes into stand-by mode. This also contributes to reduced wear and lower energy consumption.
The blast media volume of maximum 200 kg/min per turbine along with the belt speed is adjustable. The operator can automatically adapt these two parameters to the work pieces by simply selecting one of the blast programs stored in the system PLC. A work piece height sensor allows the optimum adjustment of the blow-off station installed at the machine exit. This allows the removal of residual blast media carried out with the work pieces. The blast media recycling system is equipped with a high performance magnet separator.
Because the castings are made from aluminum, the dust collectors for cleaning the exhaust air from the shot blast machines are in explosion-protected design. To save valuable manufacturing space, they are placed outside of the building.