In the course of a production expansion at Linhardt Metallwarenfabrik GmbH & Co. KG in Hambrucken Koch-Technik company renovated the complete plastic granulate supply line. The new central conveyor unit links external and internal silos with dosing and mixing systems on extrusion machines visualizing the process by using the patented Navigator material management system
Reliable clean material navigation
Handling plastic granulates is extremely significant in the extrusion business. At first, the material must always be added in the right proportions and at second a tear in the material can result in a very long restart time and thus cause high costs. The material for the new conveyor unit in Linhardt flows currently from three external silos via conveyor
lines to Koch's automatic material feeding system, Navigator. Navigator controls 20 material handling lines at once, reconciles the necessary material with the amount requested by the machine, conveys it and cleans the junction completely and automatically. This ensures that during the next handling no incorrect material or dust can reach the machine. Also for small amounts up to 5 additional materials can be fed from containers and if Linhardt needs additional materials or machines in the future, then Navigator can easily manage to control maximum of 24 material handling lines.
|Each year 330 employees of Linhardt Metallwarenfabrik produce millions of high-quality tubes and the same number of diverse closures for the cosmetics and pharmaceutical industries. Well-known medium-size companies and major international groups are supplied by these products. Linhardt Company, which has been trading since 1947, pursues the policy of satisfying its customers with goods and services of the highest quality. Recently having faced the growing demand from the cosmetics industry, the existing conveyor unit was expanded from the existing 5 extrusion lines by further 5 main extruders and co-extruders. Tubes are produced from a number of various basic components, which undergo a number of production processes with the final actual extrusion process. At the end of this production process, the finished and printed tubes can be sealed, fitted with a closure and packaged.
How does the Navigator system work? The material is sent directly from the material containers or external silos to Navigator via conveyor lines. On one side of Navigator there are transport lines to the extruders and on the other side the machine-assigned conveyor lines - one line for each demanded component. Both lines then meet in the centre and are checked once more before the conveying process can begin. After the conveying process, the loading junction is cleaned before the next loading can take place. This ensures first that each machine can have access to each material and at second that no residues from the previous material are contained in the machine conveyor line. This is a particularly important aspect in the cosmetics and pharmaceutical industries.
Mixing and dosing directly in one machine
As a rule, extruders process two principal and up to two secondary components, which are dosed and mixed in charging mixers using Koch dosing units. In Linhardt case mixing takes place directly at the input area for the extrusion lines. One of 5 extrusion lines consists of two main extruders and two co-extruders for secondary components and is used for multi-layer tubes manufacturing. The setting and management of the recipes and all important process parameters for the dosing and mixing system are undertaken by MCM control unit elaborated by Koch. This easily operated control unit has a memory for 100 recipes and a calibration mode, which calculates dosing time automatically after weighing. The user simply has to enter the percentages and then the control unit automatically calculates the dosing time.
Transparent manufacturing process
The consequences of quality shortcomings today embody high cost risks in every branch of industry. Accordingly, the subject of product quality and traceability of this process is in the focus for manufacturing companies. In order to guarantee faultless monitoring of the production process for Linhardt, process visualization was incorporated into the central supply system. This Koch visualization system allows for the complete material supply system to be monitored via PC. The existing equipment components are fully integrated in the new system. The visualization system gives users access to all informational sources.
Graphic representation of real time processes on a master control station means that the entire production cycle from external silo to a mixer can be tracked and recorded as well. All the relevant parameters, such as handling time or material allocation at Navigator station or mixer dosage recipes can be set, checked and controlled by this control station. Linhardt manufacturing extension caused that the material loads released by quality assurance should be reconciled with the conveyor system. In this process, the visualization system from Koch communicates with the existing PPS plant system and guarantees that only tested and approved material is fed for processing.
Carefully considered expansion program
Production at Linhardt has been assured by the existing fully automatic Koch conveyor system for a number of years already. When building the second conveyor system, the newly delivered Navigator was installed on a platform above the existing one for space reasons. To ensure trouble-free production during the expansion phase, Koch specialists successively integrated individual components one after the other. "We could hardly plan any shutdowns during the reconstruction and we managed to avoid it", Jorg Sprenger is pleased to say of the successful installation. "Since commissioning, the Koch system has operated without any problems".
Cleanness is the quality production guarantee
At the Linhardt factory the vacuum required to convey granulate is provided by two central rotary vane vacuum pumps, each providing 7.5 kW. They allow handling up to 350 kg of material per hour over a distance of up to 100 m. Vacuum pumps, with appropriate line cross-sections and bends; provide careful conveying of the material, thereby avoiding any build-up. The central conveyor system operates with an alternative reserve pump, which is also connected to the existing system. The reserve pump can therefore supply both systems with a vacuum.
There is a central safety filter, which cleans fully automatically, upstream of the vacuum pump. It removes contaminations that are larger than 2 microns from the conveyor air before it is vented into the atmosphere. The system thus complies with the highest requirements for compressed air purity and meets the clean room conditions without any additional measures. This is a particularly important aspect as regards the sensitive manufacturing process in the cosmetics industry.
For more than 30 years, the name of Koch-Technik has been synonymous with innovation, precision, modular flexibility and cost-effectiveness in the mixing, dosing, conveying and drying of plastic granulates and plastic powders. The use of its equipment and systems in more than 4000 plastic processing companies around the world reflects the acceptance and high efficiency of these systems in everyday production.