For its new plant in Macedonia, Marquardt wanted a genuinely 4.0, low-energy injection moulding shop. Targets achieved with the aid of Piovan and its Winfactory 4.0 system integrated with the company’s ERP
When building a new plant from scratch, implementing the latest production technology and achieving complete Industry 4.0 interconnection may sound like child’s play. And that may be the case, if all the equipment, from storage tanks to the end-of-line packaging machine, is designed to integrate and communicate transversely within the plant and with the centralised system, to manage processes from orders to quality control.
Complete production traceability, to deliver quality control and production efficiency, as well as energy efficiency – this was the objective of the Marquardt group, a major German automotive electronics supplier, when it designed its new injection moulding shop located at Veles, in Macedonia. Here, its subsidiary Schaltsysteme SCS manufactures control panels for air-conditioning systems, light switches and suspension control units for top-of-the-range Volkswagen, Daimler, Opel, Jaguar, Land Rover, Takata, TRW, Witte and BMW models. After moulding, the individual components are assembled on 25 assembly lines and then shipped to customers, following the just-in-time model.
Everything from one supplier
Marquardt’s other requirement when awarding the contract for the new raw material management system was that all equipment had to be produced, installed and maintained by a single supplier. As well as commissioning of the injection moulding machines – initially 20 and up to eighty, with different tonnage, at full capacity – the order also included component assembly with pipe lines and support constructions as well as implementation of a software for process monitoring and control of granule drying, feeding and conveying.
The need to find a single supplier also able to provide a 4.0 solution, integrated and integrable with the company’s ERP, limited the field to just a few firms internationally, with the contract finally awarded to Italian corporation Piovan, thanks also to its impressive back catalogue of high-automation projects.
The Piovan solution
The system offered starts from raw material storage in twenty-five 300-litre aluminium day tanks with electric locking and colour-coded light system for an immediate view of process status. Traceability and supervision start here, with scanning of the bar-codes of the bags of plastic loaded into the tank; to avoid manual errors, the charging hatch is not opened unless the bag’s contents code is of the correct type. From then on, all material processing and delivery to the injection moulding machine that will transform it into a finished component is controlled and managed in an automatic, documentable way.
Drying with redundancy
Granule conveying automation is entrusted to the Piovan Easylink system, which sends the material to the set of three Modula GMP50 auto-adaptive driers, initially serving 32 hoppers with capacities ranging from 100 to 400 litres, with subsequent expansion possible to respond to the moulding shop’s future needs. Within this configuration, one of the three dry-air generators operates as a redundancy dryer, which only automatically takes over if one of the processor dryers is down for reasons of malfunction or maintenance, to ensure continuous operation. The Modula units’ adaptive configuration keeps energy consumption down to a minimum, without the need for interference by the machine operator, guaranteeing impressive energy savings, one of the customer’s priority objectives.
Low energy use: here’s now
The parameters necessary for optimal plant operation are automatically acquired from the materials database: processing air capacity, drying temperature and residence time are stored with Marquardt’s proprietorial material numbering system and it takes just a few clicks to assign them to the relevant drying tank, which maintains them constant throughout the processing cycle. To ensure that only the dry air required by the process is generated, without waste, all dryer hoppers communicate with the central generators in real time to ensure that they work within an optimal range for energy saving. This is the key to the Piovan solution’s high energy efficiency.
High efficiency vacuum conveying system
On completion of this phase, the granule is transferred to the injection moulding machines by a vacuum conveying system with a circuit independent from the one which supplies the dryers, with a pump serving the two circuits in alternation (a second pump is ready to take over in the event of a main pump malfunction). Before reaching the transformation machine, the material first passes through the Easylink coupling station and then to the Pureflo receivers, also installed upstream of the drying hoppers. Piovan Pureflo receivers are filterless, which on the one hand means no filters to be cleaned – often complex operation due to the filters’ remote position – and on the other further reduces energy use, because less effort is required from the vacuum conveying system, which is not forced to operate with obstructed filters.
With its 60 inlets and the same number of outlets, the Easylink coupling station distributes the material automatically and safely to the various injection moulding machines operating in the shop. This phase is also included in the “Full Traceability Concept”, which allows real-time tracing or subsequent documentation, for quality control purposes, of the path of every granule, from tank to injection moulding machine, and then of the moulded component from ejection from the mould to shipment to the customer. The logical connection between the Marquardt ERP system and Winfactory 4.0 is based on a unique code, generated by the order management system and transformed into a barcode. Once read by the scanner integrated in the operator station, this code is entered in the Piovan supervision platform. At this point the two systems are aligned and nothing can escape their control.
Everything under control
The same Full Traceability Concept is also applied to the processes: all Piovan equipment is connected by a bus system to the Winfactory 4.0 supervision software, interfaced in its turn with the plant’s centralised production control system. Every alarm, plant stoppage or malfunction is displayed to the operator and, when possible, resolved also through remote assistance, delivering a high degree of automation, which in some cases even achieves the “Lights Out Manufacturing” level, where human intervention is reduced to an absolute minimum and machines operate non-stop, 24 hours a day.
What’s more, the Piovan system is also modular and expandable, allowing subsequent enlargements of the production shops without having to reconfigure the feeding and dosing system.