Injection moulding machines in operation 24 hours a day, seven days a week, remote control of all processes, minimal human intervention and no overnight supervision. Operating on this principle, the automated medical component factory launched three years ago in Colorado by Nordson Medical is a genuine example of Industry 4.0 and Lights Out Manufacturing, made possible by the conveying, feeding and drying system supplied by Piovan.
No-one turns on the light as night falls, because the lights are always off, in line with the “Lights Out Manufacturing” highly automated production philosophy, where human intervention is minimised and the machines operate non-stop, 24 hours a day, tended by robots and controlled by sophisticated management software.
This industrial model, adopting all the tenets of Industry 4.0, is successfully applied at the Nordson Medical plant in Loveland, Colorado, launched in 2015 with the idea of automating production to the highest possible degree. Inside a huge Class 100.000 cleanroom 3,500 square metres in area – virtually the whole injection moulding department – fifty-six injection moulding machines operate without a break, day and night, seven days a week. With clamping force from 15 to 200 tons, they are able to turn out 1.2 million pieces a day, medical devices manufactured in controlled conditions and traced in every phase to guarantee the highest quality and safety standards.
Amongst its Japanese and German electric injection moulding machines, robots and automatic packaging systems, the factory also contains an Italian contribution. The complex conveying, feeding, drying and moulding unit dosing system was designed and built by Piovan, in partnership with Una-Dyn, the US company belonging to the group of the same name. The Italian company won the contract for its ability to effectively implement the intensive automation philosophy which characterizes the plant, with the aid of tried and tested solutions.
To keep the moulding machines running without any breaks except for scheduled maintenance or incidental stoppages, granule treatment and handling are managed and regulated by the Winfactory 4.0 software, a real central control system which enables the operator to access the process parameters at any moment from remote, and check that the equipment is functioning correctly without having to actually enter the department. Lights Out Manufacturing….precisely!
The plant’s equipment comprises the very best from the Piovan product portfolio: dehumidifying system consisting of four Modula units giving a total of 25 stations; five Easylink coupling stations, Quantum series batch blenders and Pureflo filterless receivers, configured for medical application and incorporating the Ryng device. Each device has its own control unit, capable of dialoguing with Winfactory 4.0, which is interfaced in turn with the factory control system.
Everything runs like clockwork, with minimal human intervention. Until two years ago, a worker was present overnight to step in when the alarms went off. Nowadays, when dusk draws in and the cold winter winds blow from the Rocky Mountains, the department foremen leave the plant and go home to their families. They know that in an emergency the control system will alert them by means of their pager – still popular in the United States – or messages on their tablet or smartphone. And before going to the factory, they will be able to check out the problem and, in some cases, resolve it remotely.
How does it work in practice?
When the plastic granules arrive at Nordson Medical, the worker passes the scanner over the barcode and then loads them into one of the four 5,000 kg silos installed outside the plant. Depending on production planning, the Piovan Winfactory 4.0-MED system (version optimised for use in medical applications) automatically feeds the material to the machines with the aid of five Easylink automatic coupling systems, a vacuum unit (Varyo) to reduce stresses on the material, and eight kilometres of steel pipes, which run through the entire plant like a network of arteries; when necessary, granules are dried by four Modula units, managing 25 hoppers.
One special feature of the drying system must be underlined, because it is unique: if demand from the injection moulding machines falls, the dryers are automatically deactivated to conserve energy. On the other hand, if an alarm is triggered during the night and a dryer shuts down, the others are able to keep all 25 stations in operation, without slowing down or stopping production. Each moulding machine is fitted with a Pureflo filterless receiver, connected to a Quantum gravimetric batch blender, which adds pigment and additives and then precisely, constantly regulates the quantity of granules for processing. Nordson Medical also decided to install an automatic processing waste recycling system. Here again, Piovan made a major contribution: the Easylink coupling system not only conveys virgin granules to the individual moulding machine but is also able to direct regrind material from the moulding unit to the specific recycling station, which is different for each material processed. Automatic management of this phase made it possible to dispense with the presence of a human operator, opening the way to round-the-clock lights out manufacturing.
As well as being controlled by Winfactory 4.0, the entire process is also traced and recorded, to allow the causes of any defects or nonconformities to be identified and remedies taken. Once it has passed quality control, every production batch is automatically packed inside the cleanroom, prior to shipment to the end customer.