K 2010- Injection Molding New All-Electrics & Hybrids Balance Performance & Economy
The world’s largest plastics show, coming up next month in Dusseldorf, Germany, provides ample evidence of the growing sway of electric drive technology in injection molding.
The world’s largest plastics show, coming up next month in Dusseldorf, Germany, provides ample evidence of the growing sway of electric drive technology in injection molding. However, advance word of new machines to be exhibited there also clearly indicates that hydraulic technology will be with us for quite some time. Not only are new hybrid machines at least as numerous as all-electrics, but machine builders continue to re-invigorate hydraulic machine design. In a growing number of cases, this is through use of electric servo pumps to provide hydraulic power with much greater energy efficiency (though some vendors categorize such systems as hybrids). The clear message is that electric and hydraulic technologies will be applied where each is most cost-effective—or else according to customers’ taste.
MACHINES FOR SPECIAL PROCESSES
Both Engel and KraussMaffei are showing systems for exotic multi-material molding and “organic hybrid” composites. At K 2004 and K 2007, KM (kraussmaffei.com) showed its SkinForm process for overmolding a rigid thermoplastic substrate with two-component thermoset polyurethane (PUR) in the same mold. This year, KM ups the ante with a three-component (3C) demonstration, using an MX large two-platen hydraulic machine to mold the substrate and overmold part of it with TPE. Another portion of the substrate will be overmolded with PUR by a KM RimStar Nano metering unit integrated with the injection machine.
Engel (engelglobal.com/na) will take a different approach to PUR overmolding—using a very thin, clear coating of PUR, not for soft-touch haptics, but to protect a decorative film back-molded with the rigid substrate in the first of two machine cycles. As reported in July (see Learn More box), Engel is working with Hennecke (hennecke.com) for the PUR metering hardware.
Engel is also proposing to use this combination technology to robotically dispense PUR foam-in-place seals and gaskets on freshly molded parts. That concept will also be highlighted at K by PlasmaTreat (plasmatreat.de) and CeraCon (ceracon.com). In adjointing booths, they will demonstrate two-shot molding of a PUR seal on a thermoplastic part. The process injects Ceracon’s one-component S-FIT PUR system, which is physically foamed with compressed air and has a heat-activated catalyst to cure in the mold. PlasmaTreat’s contribution is use of its atmospheric plasma technology to selectively treat the mold surface between cycles with an anti-stick coating to counteract the PUR’s adhesiveness.
Other unusual multi-component molding exhibits include Kortec’s debut of its coinjected multilayer color gradation technology (MCGT) for adding special aesthetics to PET bottles. Kortec (kortec.com) supplies complete preform coinjection systems with Husky machines.
In addition, Arburg (arburg.com) will demonstrate novel overmolding technology from German moldmaker Zahoransky Formenbau GmbH (zahoransky-group.com). As we reported last October (see Learn More), Zahoransky’s Servo Cavity Positioning System (SCPS) indexes sets of cores and parts upward through a mold by means a of a servo-driven spindle without having to open the mold between cycles. The cores and parts eventually pass through the top of the mold for external demolding without any effect on cycle time. SCPS will be demonstrated with a 12-cavity toothbrush mold running in Arburg’s all-electric Allrounder 720A with 320-m.t. clamp and twin injectors.
Arburg and others will also highlight micromolding capabilities. Arburg will show a new retrofittable, two-stage micro-injection unit (2.3 cc capacity) for its electric Allrounder A machines (reported in June, see Learn More). Engel will bring its new electric, single-stage micro-injector, reported in July (see Learn More). Wittmann Battenfeld will exhibit its completely redesigned all-electric Microsystem micromolder, now available in 5- and 15-m.t. models (reported in June, see Learn More). And Boy Machines (boymachines.com) will show off its new XS Series of machines, introduced at NPE 2009, for molding small and micro parts with shot sizes of 0.1 to 8 cc. At K, Boy will show how the XS machines allow auxiliaries for drying, coloring, and conveying to be installed within the machine’s envelope to save floor space. A new control device allows removal and placement of parts.
Engel and KraussMaffei will highlight a different sort of overmolding approach for so-called “hybrid” composites. In the past, these have involved selective “outsert” overmolding of preformed sheet-metal pieces. In the interest of weight savings, the R&D focus is shifting to long-fiber plastic reinforced sheet as the substrate. Both Engel and KM have approaches to forming preheated sheet in the mold and then overmolding ribs, attachment points, etc., possibly with the addition of foaming or gas assist (see June article in Learn More). KM will use its CX Series 300-m.t. injection molding compounder to chop and blend continuous glass fibers with nylon for the overmolding compound.
Other specialities on display at the show:
- Engel’s new approach to machine-integrated mold cooling using in-mold temperature sensors.
- Wittmann Battenfeld’s water-assist Projectile Injection Technology (Aquamold PIT) and new Ball-Filled Mold (BFM) for faster heat/cool molding (see June article in Learn More).
- Adding a new layer of complexity to in-mold labeling (IML), Ferromatik Milacron Europe (ferromatik.com) will demonstrate a high-speed 300-m.t. Vitesse hybrid machine molding rectangular lids in a 4+4 stack mold with PP film labels in one parting line and paper labels in the other, on 5-sec cycles.
- Not to be outdone, Sumitomo Demag (sumitomo-shi-demag.eu) will combine two-shot molding with in-mold decoration (IMD) using two different films on one part. This IDM-Multi-K process will be demonstrated on a hydraulic Systec multi 210 press producing an auto interior part under Class 10,000 cleanroom conditions. It will use clear and colored resins and both translucent and “piano black” IMD films for a day/night viewable panel.
NEW ELECTRICS & HYBRIDS
Machine builders are launching new series and upgrading or adding new sizes to existing lines. Engel, for example, has added a smaller model (100 m.t.) to its e-motion T all-electric tiebar presses and also is rolling out the e-cap system, an all-electric line dedicated to caps and closures and designed to compete with hydraulic accumulator machines (reported in July, see Learn More).
Haitian of China (called Absolute Haitian in the U.S.) has added to the Zhafir Venus Series of all-electrics introduced at NPE 2009 a new VE/p (packaging) version with increased injection speed and response time of 25 millisec, as well as a special high-performance screw. The VE/p is said to cost 30% to 40% less than most premium all-electric machines from Europe or Japan.
Another premiere from Haitian is the Zhafir Mercury Series of all-electric tieberless machines with two-stage injection for high-end molding jobs. Production will begin in 2011 of models from 30 to 500 m.t.
Negri Bossi is introducing a completely new all-electric design, the FE Series of 120 to 400 m.t. It has an improved belt drive, energy-recovery system, max. injection speed of 230 mm/sec, and new CANbus touchscreen control.
As reported in June, Wittmann Battenfeld has four additional models in its new EcoPower all-electric series, extending the range from 55 to 300 m.t.
Sumitomo Demag has four new models up to 450 m.t. in its IntElect Smart all-electric line. The IntElect Smart series (50 to 450 m.t.) is based on Japanese SE electric drive technology and is the company’s all-electric version with the highest speed and precision. The IntElect Performance version is based on Demag technology and has water-cooled electric drives (vs. air-cooled on the Smart series), which makes it optimal for some cleanroom uses.
The news from Ferromatik Milacron at the show will be the coming launch (in 2011) of the F-Series, which will gradually replace the existing Ferromatik Milacron lines, including the Elektra all-electrics, Vitesse hybrids, and K-Tec hydraulics. The complete F-Series will span 10 models from 50 to 650 m.t. aimed at packaging, consumer goods, and medical parts. This single machine series will be highly modular to allow a choice of emphasis on performance, energy consumption, dynamics, or precision. Molders can mix and match electric or hydraulic drives for each machine axis, providing customized all-electric, hybrid, and hydraulic options.
KraussMaffei will show the new Ultra injection unit for thin-wall molding on its all-electric EX Series (first introduced at last fall’s Fakuma show; see Learn More.)
In hybrids, Arburg is expanding the Hidrive line introduced at Fakuma with a bigger model—500 m.t.—which has a hydraulic accumulator for high-speed injection.
Haitian is bringing out a lower-cost version of its Mars series “hybrids,” which are hydraulic toggle machines powered by a servo pump. The new Mars Eco series from 60 to 1000 m.t. is aimed at “simple standard parts,” the company says. It has a “streamlined” option package and prices around half those of European standard presses.
This past April, Haitian introduced the higher end Pallas line, which is based on the Mars platform but with increased speed and precision. Models from 60 to 450 m.t. have a revised toggle system; those from 530 to 1000 m.t. are a new two-platen design.
Negri Bossi’s Vector Series of hybrid toggles with electric screw drive has been redesigned. Ranging from 800 to 1500 m.t., the line has a new gearbox that’s quieter and more efficient, increased stroke on the clamp and ejector, easier access to the mold area, quick-change injection unit, variable-volume pumps, and touchscreen controls.
As we reported last month, Negri Bossi’s Janus modular hybrid toggle line (introduced at NPE 2009) has been expanded with the new Smart Energy system (Janus SE), which combines energy efficiency approaching that of an all-electric with performance above that of electric machines. From 160 to 900 m.t., Janus SE combines a variable-speed electric pump motor and a hydraulic accumulator.
Negri Bossi is also introducing the VS-E Series of modular hydraulic toggles with a servo pump drive, said to cut energy consumption by 45% vs. standard hydraulics. This is one variant of the brand-new modular VS Series of 110 to 430 m.t. hydraulic presses. They have quick-change injection units, larger mold capacity, variable-volume pumps, and new Columbia controller with 15-in. TFT screen.
Netstal is introducing two new hybrid models; they carry the Elion brand that has designated its all-electric range, though the new machines incorporate the hybrid injection unit of Netstal’s Evos line. The new Elion 2200 (220 m.t.) and 2800 (280 m.t.) have electric clamp and screw drive but hydraulic injection. They are also the first machines to show off the new, freely programmable aXos sequence control. Current Netstal machines have a fixed sequence that can be influenced by over 15,000 parameters. With aXos, customers are free to program any sequence their process requires. Inconsistencies will be highlighted automatically before activation. The system includes an auxiliary control definition page, and freqently used auxiliary controls, like a core puller, will be built into the system. Molders can use the pre-configured auxiliary controls or build their own with a few clicks. Besides the main screen, there is an icon-based upper screen and folding membrane keyboard for manual operation.
Coming from Sumitomo Demag is a new generation of its El-Exis hybrid dedicated to high-speed packaging operations. The El-Exis SP ranges from 150 to 750 m.t. and has a hybrid clamp, direct-drive servo screw rotation, accumulator-assisted injection, and NC5 control with touchscreen and keypanel (an enhancement of the NC4 predecessor).
HYDRAULIC PRESSES, ROBOTS, TOOLING
Sumitomo Demag is also expanding its hydraulic Systec line with larger models of up to 1000 m.t.; sizes up to 2000 m.t. are in the pipeline. The company has added variable-speed pump drive, called Active Drive, to its hydraulic presses, reportedly cutting energy consumption by as much as 45%, depending on the cycle.
As reported in June (see Learn More), Wittmann Battenfeld has come out with a brand-new MacroPower two-platen hydraulic line from 800 to 1600 m.t. The company recommends an optional servo pump on these presses to save energy (up to 25% or more).
As for other K show introductions:
- Arburg will bring out its Selogica Assistant, said to be a uniquely simple, menu-guided procedure for supervised setup, with “teaching” functions for the entire mold sequence. Operators are led through five logical steps to create an entire cycle sequence.
- KraussMaffei is offering a new Energy Analysis Tool for monitoring power consumption of KM machines in real time. Specific energy demand for various machine functions—mold opening and closing, plasticating, injection, holding, and barrel heating—is displayed on the operator panel.
- Husky Injection Molding Systems (husky.ca) will highlight its new Encore program of “structured upgrade solutions” to help customers maximize the useful life of machines less than 20 years old. The program can take two directions: One is to maintain performance of a machine when it becomes prone to deterioration. The other is to improve existing system performance to better than its original condition.
- In robots, look for the debut of Primus side-entry robots from Wittmann Battenfeld and viper servo robots from Engel (see Learn More). Also new will be the S5-25 servo robot from Sepro (seproamerica.com) for machines of 120 to 450 tons. It’s the second model in the new S5 line reported last month (see Learn More). Also, Ferromatic Milacron will exhibit its new FMR 8-5 Advanced robot built by Wemo of Sweden. Sumitomo Demag will bring a new SDR 33 robot jointly developed with Sepro. And Negri Bossi will operate new Flash robots.
- In tooling, DME (dme.net) will display its new hydraulic locking cylinder for actuating core pulls and slides. It uses proximity switches to sense when the cylinders are fully extended or retracted. Incoe (incoe.com) has a new, retrofittable SoftGate speed control for hot-runner valve pins. Controlled opening of the valve gate is said to improve surface quality in large, cosmetic parts. Incoe also improved its Direct-Flo Gold hot runners with longer heating elements, reducing the area needed to accommodate wires on the outside of the heater and along the nozzle.
- German automation supplier Waldorf Technik (waldorf-technik.de) will have a work cell at Netstal’s booth demolding medical parts from 96 cavities with individual control of all 96 grippers. The parts from groups of six cavities will be deposited in 16 containers to allow the customer to identify and segregate batches if defects are detected later. Cavity separation will also be shown at Sumitomo Demag’s booth, where Waldorf Technik will demold 32 pipette tips with camera-based 100% QC.
Ultimate Control for the Toughest Molding Jobs
Every molding machine has to shut down periodically for a mold set-up.
Demands to create smaller, lighter parts have made thin-wall molding one of the most sought after capabilities for an injection molder.