Technological innovation in the moulding sector, just like in nature, does not leap forward in bounds. It is, instead, a gradual evolutionary path that can branch and move in different directions, but in the medium-long term it makes a sort of natural selection that rewards the most efficient, effective and least costly technology. Except, unlike in nature, it sometimes does not deviate from the main path. In recent years, significant strides forward have been made in regard to energy consumption, precision and cycle repeatability, without forgetting reliability and machine safety, while the fourth industrial revolution is beginning to loom on the horizon, driven by distributed production and intelligent manufacturing.
Innovations in the spotlight
Fakuma takes place in October in Friedrichshafen, in the south of Germany. It is held two out of three years alternating with K in Düsseldorf and offers an opportunity to examine the state of the art for injection moulding technology. Launched as a regional event for the Bavarian, Swiss and Austrian markets, over time it has grown in importance on the European fair scene. A high level of specialisation, with a strong inclination for injection moulding, is one aspect behind its success. Many sector companies welcome the fair as an opportunity to showcase their latest developments. It is no coincidence that Euromap has chosen this venue to launch the new energy label which, like the label for coolers or conditioners, will help moulders to evaluate and compare the energy efficiency of injection and blow moulding machines, and other processing technology in the future also.
The same goes for injection machinery manufacturers.
Wittmann Battenfeld, for example, chose Friedrichshafen to launch its new SmartPower family of small tonnage machinees, which will be available from next year in the 25 to 120 tons clamping force range. In construction terms, the entire range is equipped with servo drives, combining the benefits of hydraulic clamping with the precision, repeatability, clean operation and low energy consumption of electric machines. At Fakuma were introduced two models with clamping force of 60 and 120 tons respectively. The first manufactured a polyamide connecting rod for a commachineor, using an 8-cavity mould supplied by Greiner Assistec, Austria. A WS80 servo sprue picker from Wittmann, also a novelty, removed the sprue. The second machine, a SmartPower 120/350, produced a penholder from liquid silicon (LSR) in a 4-cavity mould supplied by Elasmo Systems, Austria, without waste and fully automatically.
KraussMaffei, on the other hand, decided to expand in the higher end of the range with its electrical machines in the AX series, introducing two models with clamping force of 450 and 550 tons respectively. A decision motivated by the growing demand for increasingly powerful electric machines. For this series, the German manufacturer announced an energy efficiency index of 9+ according to the new Euromap class 60.1, i.e. it reduced energy consumption by virtually 50% compared to similar hydraulic injection moulding machines. At the fair the smallest manufacturing cell, an AX 50-180, showed the production of a polypropylene container. A larger machine, the AX 130-750 with integrated MuCell system, demonstrated the moulding of foaming components with high-gloss surfaces.
25 years of tiebarless technology
Engel was celebrating twenty-five years since the launch of its tiebarless technology machine, unveiled at the K 1989 plastics trade show. To mark the occasion, it displayed the new 50 TL version with 50 t clamping force of the tiebarless e-motion range introduced last year by the Austrian manufacturer, initially in a 30 t version. As with the smaller variant, the new 50 TL features a one-piece machine frame that makes the injection moulding machine lighter and more compact than comparable all-electric machines of other types. The design also guarantees very high platen parallelism and even distribution of clamping force. The clamping unit fits a three-point, sealed, maintenance-free toggle lever type, with optimized servoelectric drive technology for rapid moulding.
Updated by aesthetic restyling, the duo range is ergonomic and functional: the new version is lower, it now has a more accessible moulding and nozzle area, and a roller guidance system has been added for the mobile platen, reducing energy consumption and keeping the moulding area clean.
One component is not enough
Multiple component moulding capacity is proving, along with energy efficiency, to be one of the great technological drivers of injection moulding. The production of finished or semi-finished pieces reduces production times and costs, and eliminates assembly stages. The trend appears to be moving towards combining different types of materials with different consistency, rigid or soft, moulded and finished in increasingly complex and automated cells.
Negri Bossi, for example, showed how to manufacture snorkeling goggles in three-component material using the eCANBIO evolution 210 LSR machine, fitted with the new Smart Flex clamping system: PBT (frame), LSR70 (lenses) and LSR30 (elastic band and seal) with the aid of nitrogen for cellular foam. Liquid silicone and nitrogen are mixed during the feed stage through two lines: the first works on the two components individually, the second during the silicone component mixing stage. The machine has a traditional configuration, with the main injector introducing the thermoplastic material into the mould which forms the glasses frame; the other three lines, fitted with cold channels supplied by Guzzini, are connected directly to the mould to produce the seal (LSR30), the elastic band (LSR30) and the lens (LSR70). The part is finished when it exits the machine, thanks to the moulding process featuring internal welding developed by the Milan-based (Italy) company.
Ferromatik Milacron, Kortec and Mold Masters, all part of the Milacron group, have worked together to assemble a thin-wall bi-component packaging moulding unit consisting of an F 220 hybrid machine with clamping force of 220 tons, with Kortec Coinjection Moulding technology and Mold Masters injection unit. Using a 4-cavity mould, at the fair the unit made multiple wall, two-component cups to be filled with fruit compote. This structure consists of two polypropylene layers and a wafer-thin EVOH layer in its core to serve as a barrier. The cups were injected at a cycle time of about 7 seconds.
Wittmann Battenfeld brought a multiple component large tonnage machine, the MacroPower 450/5100H/2250Y featuring two-component sandwich technology. The machine demonstrated the manufacture of polypropylene flower pots with an attractive surface, compact shell and a foamed core for low part weight.
In this segment, KraussMaffei displayed three lines – CX, GX and MX – with clamping forces ranging from 35 to 5,500 tons. At Fakuma, it announced expansion of the GX two-platen machine range with hydraulic drive for positioning injection units: in addition to the GXW version with SpinForm technology unveiled at the last K, the configurations GXH (two or more horizontal and parallel injection units), and GXV (second unit tilted downwards and overlapping the first) will also be available in the future. The machines can fit a new, faster, more precise electric rotating platen moving independently from the other axes.
Engel produced three-component medical parts with insert using a tiebarless e-victory 160 combi injection moulding machine with integrated easix TX-90 robot and mould supplied by Hack Formenbau. In one mould cycle taking just 12 seconds, it produced drip chambers with integrated filter for blood transfusions: each piece consisted of one ABS and one PP component, injection moulded in a single work step and joined by overmoulding with additional polypropylene.
Out of the ordinary
There was no shortage of avant-garde technology, such as 3D printing, various processes being combined within the moulding cycle, or further advances in integrating upstream and downstream steps by injection moulding machinery, trends driven by the need to boost industrialisation to meet the demands of automotive, packaging, medical, and other sectors.
Arburg reproposed its 3D printing production solution, the 3D Freeformer, which attracted numerous visitors to its booth at the previous exhibition, curious about its layout which is so different from traditional injection moulding machines, moulding one-off parts or small-volume series directly from CAD data, without requiring a mould and using standard granules.
The German manufacturer brought two exhibits to Friedrichshafen, both having a three-axis support for the two nozzles. These produced plastic parts by overlaying two different materials.
Wittmann Battenfeld combined CellMould (foaming), BFMould (variothermal mould temperature control) and HiP (High Precision Opening) technology on an EcoPower 240/1330 machine, in order to produce automotive parts of lightweight structured foam with a high quality surface, two features that are hard to achieve together.
Remaining on the topic of light weight, Arburg demonstrated the PCIM process (Particle-foam Composite Injection Moulding), overlaying thermoplastics on a foam part, forming a permanent bond by selective melting of the insert.
Engel is also focusing on its manufacturing cells which combine two technologies to create parts with characteristics pushing the limitations of possible technology. At Fakuma it showed the production of centre console parts in PC and ABS on a duo 2550/550 injection moulding machine using foammelt processes (the MuCell foam injection moulding process) and Variomelt (a variothermal injection moulding process): the result was a thin-walled, lightweight part with no post-cooling sink marks and quality high quality finish straight from the mould.
Towards smart manufacturing
Another topic destined over the next few years to become key in plastic processing is the smart factory or, as the Germans call it, “Industry 4.0”. This is a concept of advanced, integrated automation which, according to the experts, will revolutionise manufacturing over the next ten or twenty years. All operations at the factories of the future – from order to production management, through to process data analysis – will be interconnected via a smart network, featuring a high degree of autonomy. This will require the introduction of methods, standards, platforms and technology infrastructure that interconnect, share data and make decisions.
At Fakuma, Arburg provided a taste of what the future will bring with its manufacturing cell for plastic scissors. An Allrounder 370 E electric made the two parts, handle and blade, then an individual QR code was applied by laser, making it possible to retrieve the main process parameters online. Moreover, the scissors can be customised to individual requirements using the 3D Freeformer. The process is controlled and monitored by a centralised IT system (ALS), which analyses and saves process data and transmits it to a web server to be shared online.