The packing of aluminium extrusions has always been one of the particularly labour-intensive operations in extrusion plants. At the extrusion plant of Gerhardi Alutech in Lüdenscheid H+H Herrmann + Hieber created an semi-automatic packing station in which manually activity has been reduced to loading on the sections.
The rationalisation of packing means that the workers are relieved of as many auxiliary activities as possible. That is achieved by largely automating all the transport and by designing the packing stations ergonomically.
- Transport mechanisation. The material transport tasks consist on the one hand of bringing in the goods to be packed and the packing materials, and on the other hand carrying away the packed sections and the empty racks. In these contexts solution approaches depend on the organisation and layout of the plant, and must therefore be planned individually (crane transport, roller tracks).
- Design of the packing stations. The design should make full use of every possible ergonomic option. Suitable work aids (lifting tables for the correct working height, dispensers for packing materials. etc.) boost the workers’ individual packing performance and at the same time make his work physically easier.
Moreover, for semi-automatic packing the rack buffers are replaced by an automatic section destacker and section supply belts. An example of that arrangement is the extension work carried out at the extrusion plant of Gerhardi Alutech in Lüdenscheid. There, when the new extrusion line had been built the production of both lines was brought together at a central semi-automatic packing station. In this case two packing positions are served by a shared destacker.
The destacking machine, arranged in front of the packing stations, can deal with racks of different widths in any sequence. Furthermore, when both packing stations are being served at the same time, it has to deposit the layers – depending on the packing position envisaged – onto two separate transport belts. During destacking the grippers take hold of the intermediate layers (spacers), lift up the layers and transport them to a transverse conveyor that moves them to the packing station.
The handling and positioning of the spacer layers is in this case also fully automated. The spacers are positioned on a separate transport belt under the transverse conveyor, which moves them clear of the area of the destacker. In a separate, special device the spacers are collected and returned to the stacking machine by a transport system of their own.