Injection Molding: The future is Here
By Mark Stephen, managing editor
Ask most plastics professionals and they'll tell you that in the processing world, injection molding commands a lot of attention. If it were a country, it would be America. If it were a crime fighter, it would be Superman.
Ask most plastics professionals and they’ll tell you that in the processing world, injection molding commands a lot of attention. If it were a country, it would be America. If it were a crime fighter, it would be Superman.
If you wanted to actually see the Man of Steel, you’d probably have to settle for going to the video store. For the latest in injection molding technology, the best place to be was in Chicago, at NPE2009 in June.
Whether you did or didn’t attend the show, here’s some of what was new in hydraulic, all-electric, and hybrid technology.
Battenfeld‘s new TM Xpress is designed for high speed, thin-wall packaging applications such as in-mold labelling (IML), with standard high performance features that provide precision, accuracy, and repeatability for the most demanding short cycle applications, the company said.
Hydraulic accumulators allow high injection speeds up to 2,209 cm3 per second, and acceleration rates up to 10,000 mm per second, which are required for thin-wall parts. The accumulators are also used to allow ejector or core pull movements to take place parallel with the clamp movement, as well as for simultaneous injection during clamp pressure build-up.
The TM Xpress also features an optimized toggle design to reduce lubrication to a minimum. And there are no moving platen bushings, so the tie bars are free of lubrication. High precision linear guides are used to support and guide the moving platen, eliminating the need to make adjustments for heavy molds.
The AC servo screw motor is standard and offers plasticizing independent of all other machine functions. Injection, hold, and back pressure are controlled via servo valves. The machine is designed for quiet operation, producing less than 72 dbA.
Besides IML, the TM Xpress can handle a variety of other products, such as caps and closures, buckets, and medical parts.
New from Boy Machines is the Boy XS unit, intended for high precision micro and sprueless single-cavity injection molding.
An 11-ton clamp machine, the XS is available in both horizontal and vertical configurations, with a compact footprint: the horizontal XS machine needs 0.81 m2 of floor space, while the vertical Boy XS V requires just 0.63 m2.
The two diagonally positioned tiebars allow easy access to the mold area, the company said, while the ejector is also easy to get at. Both configurations come with 12-mm plasticating units, and Boy Machines’s Procan Alpha Controls.
Engel introduced the new duo pico line of two-platen machines, a hydraulic product line built for mid-size molding applications, and described as compact, fast, and economical.
Designed for quality requirements, and available in sizes from 500 to 770 tons, the pico design provides a minimal footprint (under 24′ for duo 550 pico), low weight, and a dry cycle of 2.6 seconds.
The duo pico achieves energy savings similar to fully electric machines, Engel said, but has the ability to maintain that energy-efficiency in applications utilizing hydraulic components, such as hydraulic core pulls, hot runner needles, and mold mounting systems. The variable drive motor is intended to achieve the right operating point for each movement.
The machine is equipped with an electric plasticizing unit, which allows the hydraulic pumps to idle during plasticizing, for additional energy savings.
Available with clamping forces between 66 to 352 tons, the new Allrounder H/Hidrive series from Arburg is designed for shorter cycles.
The machines have hydraulic injection units from the company’s Allrounder S Advance line, coupled with an accumulator, and a servo electric screw drive for plastication.
According to Arburg’s sales director Helmut Heinson, the Hidrive machines can offer energy savings of up to 40 per cent over a standard hydraulic machine, compared with 50 per cent for an all-electric machine. Part of the reason for the energy savings is the Hidrive’s use of energy recovery during braking, Heinson added.
Changing of the hydraulic accumulator is dynamically regulated, Heinson said, meaning that the pressure level is automatically adapted to the actual demand, thereby using the minimum required pump capacity.
The new Mars series from Haitian is designed to integrate all of the features of the traditional hydraulic Haitian Saturn series, but with the enhancements of a servo motor dynamic control system to improve molding precision, and reduce energy consumption.
The response time of the drive system is very fast, according to Glenn Frohring, president of Absolute Haitian. “It requires 0.05 seconds to reach the maximum power output,” he said. “Cycle time is substantially shortened compared with traditional hydraulic machines, and efficiency is significantly improved.”
Compared with conventional hydraulic machines, energy savings of between 20 per cent and 80 per cent can be reached, Frohring said.
Milacron‘s new PowerPak unit has power in the form of an accumulator offered on the injection end to give comfort to processors who might not normally consider a hybrid machine. Designed to incorporate and extend the company’s Powerline NT series, the PowerPak is available as an all-electric on all four machine axis’s (clamp, injection, ejection, extruder), or as a combination of the ejector and injection axis as hydraulic.
According to Andy Stirn, Milacron’s market development manager, the model offers processors flexibility with machine design, and provides the low energy consumption in the packaging industry for thin-wall, high-speed consumer products.
Standard features of PowerPak include Mosaic control with enhanced capabilities and multiple language capabilities, SERVTEK feed screw technology including the BARR VBET feed screw, elimination of servo valve technology, and split base design for easy rigging and installation.
“Initial models will be available in sizes of 440 and 550 tons of clamping force, and we plan to follow with models up to 1,125 tons,” Stirn said.
Negri Bossi‘s new range of Janus hybrid machines combine electric actuators for mold clamping and screw rotation with hydraulic actuators for injection phase, and offer overlapping movements, as well as a high degree of configuration flexibility.
According to Larry Pascucci, general manager of Negri Bossi Inc., the Janus line marks the first time that the company has offered a fully hybrid unit, previous combined machines having been restricted to hydraulic machines with electric screw drive.
Negri Bossi has engineered the new Janus series to achieve the same energy consumption of a full electric machine on all the clamping unit functions, Pascucci said. The technical solutions adopted are the same as the company’s Red Devil series. The clamping unit movements are achieved by means of an electric torque motor directly coupled to the recirculating ball-screw. The core puller solution is the same as that on the Canbel full electric machines.
Janus machines can be supplied with either variable delivery pumps, when the molding is a technical part requiring an injection speed up to a maximum of 100 mm per second; or accumulators and servo valve for speeds up to 250 mm per second for thin-wall parts, or very short cycle times.
All-electric machine pioneer Nissei showed its NEX series, which offer automatic clamping force correction function, and high precision metering control as standard equipment.
The toggle-type automatic clamping force mechanism can automatically correct the clamping force that was affected due to the rise of mold temperature during automatic or continuous operation of a molding machine. This function also allows users to change the clamping forc
e during automatic operation.
High precision metering control permits the selection of a control mode “Pre Pack” or “Precision Metering,” which materialize high precision metering during molding operation.
One of the models, the all-electric NEX 110-18E, has been crafted specifically for molding bioresins such as polylactic acid.
Sumitomo Plastics Machinery, recently affiliated with Demag Plastics Group, introduced the new SE-DUZ direct-drive all-electric model at NPE2009, running a 64-cavity medical pipette mold on a 10-second cycle.
Like the predecessor SE-DU series, the SE-DUZ features four direct-drive, Sumitomo AC servo motors with full closed-loop control, and digital sensors for plasticizing, injection, clamping, and ejection. All four motors are beltless, Sumitomo said, providing mechanical efficiency, repeatability, and durability, and avoiding the problems associated with belt adjustment and dust.
Designed for clean room environments, Toshiba Machine‘s all-electric EC180 series uses no hydraulic oil, eliminating spills, contamination, and disposal, and cutting machine electricity usage up to 80 per cent, the company said. It also runs quieter, reducing the need for ear protection, and improving work conditions.
At NPE2009, Toshiba Machine showcased the all-electric EC180NII, with IML technology from Imdecol, to mass-produce ready-to-use plastic containers in a single turnkey operation.
According to Toshiba Machine’s technical sales manager Mike Werner, Imdecol’s IML complements Toshiba’s EC180NII, a 180-ton, high speed, high cycling, high performance system that is well suited for packaging, medical, food processing, and other applications. CPL
RESOURCE LIST
Absolute Haitian (Worcester, Mass.); www.absolutehaitian.com; 508-459-5372
Shadow Automation (Uxbridge, Ont.); 905-649-2652
Lutek Plastic Equipment Inc. (Dorval, Que.); 514-421-8963
Arburg Inc. (Newington, Conn.); www.arburg.com; 860-667-6500
Dier International Plastics Inc. (Unionville, Ont.); 905-474-9874
D Cube (Montreal); 514-272-0500
Battenfeld (Wittmann Canada Inc.) (Richmond Hill, Ont.); www.wittmann-canada.com; 1-888-466-8266
Boy Machines Inc. (Exton, Pa.) www.boymachines.com; 610-363-9121
Plascom Plastic Machinery (Toronto); 416-491-8450
Barway Plastic Equipment Inc. (Vaudreuil-Dorion, Que.); 450-455-1396
Engel Canada Inc. (Guelph, Ont.); www.engelglobal.com/na; 519-836-0220
Milacron Canada Inc. (Burlington, Ont.); www.milacron.com; 905-319-1919
Accuplast Solutions (Kirkland, Que.); 1-866-630-0808
Negri Bossi Inc. (Mississauga, Ont.); www.negribossi.com; 905-625-7257
Nissei Plastic Industrial Co./En-Plas Inc. (Toronto); www.en-plasinc.com; 416-286-3030
Sumitomo Plastics Machinery (Norcross, Ga.); www.sumitomoPM.com; 770-447-5430
Plastics Machinery Inc. (Newmarket, Ont.); 905-895-5054
Toshiba Machine Co. America (Elk Grove, Ill.); www.toshiba-machine.com; 1-888-593-1616
CNSmith Plastics Machinery Sales (Georgetown, Ont.); 416-917-3737
