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NPE2018 Show Daily - Monday

NPE is truly ‘Breaking the Mold’ as a multifaceted experience, with activities, discoveries and opportunities to satisfy the needs of anyone who works in the plastics industry or has a need to know about plastics

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MONDAY NPE 2018 : THE PLASTICS SHOW SHOW DAILY NPE Is U.S. Debut for Campetella Roboঞc Center Novel Injecঞon Unit With In-Line Screw/Plunger By Mahew H. Naitove Plascs Technology Longstanding limitaঞons of convenঞonal re- ciprocaঞng-screw injecঞon molding machines are addressed by the new Inject-EX system from Md Plasঞcs. This injecঞon unit, appear- ing for the first ঞme at NPE2018, can be sup- plied with hydraulic, hybrid, or all-electric drives. The all-electric version consists of a servo-driven screw connected in line with a plunger. The screw and plunger thereby move together as the enঞre injecঞon unit recipro- cates, driven by two servo motors and ballscrews mounted on either side of the unit. As explained by Michael Durina, president of Md Plasঞcs, one well-known issue of con- venঞonal injecঞon machines is inconsistent shot volume due to variability in closing of the check valve on the end of the screw at the start of injecঞon. Another issue is that as the screw retracts during recovery, pellets experience a conঞnuously changing L/D so their shear exposure is inconsistent, which leads to melt-viscosity variaঞon. That effect is exacerbated by the fact that when the screw moves forward during injecঞon, pellets fall down from the hopper into the empty flights that are provided to fill the shot. Those pellets are not compacted efficiently, which creates an issue during recovery of the next shot by adding shear due to screw slippage and a pause in recovery ঞme. The Inject-EX system solves the second problem because the screw (the company's Posi-Melt design) is staঞonary with respect to the feed hopper, which moves back and forth with the rest of the injecঞon unit. Plasঞcaঞon of every pellet is therefore consistent, as in conঞnuous extrusion, says Durina, even though this screw operates disconঞnuously. As for the first problem, there is a check valve at the front of the screw, where it tran- siঞons to the plunger, but the valve is actually the same design used in Md Plasঞcs' Mini- Shut shutoff nozzles rather than its nonreturn valves. This is a poppet valve that is spring loaded with Belleville washers. It therefore shuts immediately when the screw stops turning, not when it moves forward to inject. Melt passing through the valve is chan- neled through the center of the plunger unঞl it reaches the front end, where it accumulates the shot in front of the plunger. To fill the mold, the enঞre injecঞon unit moves forward, emptying the melt chamber in front of the plunger. Durina says this arrangement is both simpler and less costly than exisঞng screw/ plunger systems. What's more, the Inject-EX machine will use Md Plasঞcs' exclusive Temp-Tek melt-temperature and pressure sensor. One sensor will be embedded in the melt chamber at the end of the plunger; another will be placed in the feed hopper. The first sensor will help ensure injecঞon of a consistent mass of plasঞc, which is a funcঞon of consis- tent volume and density. The other will pro- vide potenঞally valuable informaঞon about the temperature of pellets entering the screw, Durina says. New Inject-EX injecঞon unit from Md Plasঞcs, here shown in an all-electric version for LSR. By Mahew H. Naitove Plascs Technology U.S. molders have an opportunity at NPE to acquaint themselves with Campetella Robot- ic Center, an important Italian robot produc- er. Campetella is a family-owned firm that has been dedicated to automaঞon for over 120 years. It is represented in North America by Hunter Automaঞon & Roboঞcs, which was formed for that purpose in 2014. Cam- petella offers a full line of top-entry and side-entry, all-servo linear robots with three or five axes, and servo sprue pickers, for ma- chines from 30 to 5000 tons. Its robots are said to be very quiet, grease- less, and low-vibraঞon, as well as universal— their modular design can be switched from operator side to non-operator side or T-beam mounঞng in 2 hr, unlike the majority of mod- els on the market, the company claims. They also can be moved easily from machine to machine. In addiঞon, these robots are com- pact: A side-entry model reportedly takes up the same space as a top-entry model from other suppliers. Campetella specializes in IML with high- speed, side-entry robots. In Europe, it has collaborated in IML projects with machine suppliers such as Arburg, Engel, KraussMaffei, Netstal, Toyo, and others. It has supplied a complete lights-out IML system in Italy for 5700 food trays/hr, molded on a 550-ton press in 5 sec, with secondary automaঞon for checking label posiঞon, barcode verificaঞon, and stacking in boxes with protecঞve PE film. At NPE, Campetella provides the Maxi Modula side-entry robot for an IML demon- straঞon that is expected to catch the aen- ঞon of bucket and pail molders: At the KraussMaffei booth, a two-platen GX press of 900 m.t. molds two 5-gal paint pails in under 14 sec. Unঞl now, these buckets have mostly been printed. Campetella has its own booth with an En- gel machine molding four airline cups in well under 3 sec. An SM2 side-entry robot with servo wrist and vision capability demolds the parts. Also on display is the new Spin X-Se- ries four-axis SCARA robot for stacking parts. It comes with payload capacity up to 50 kg (110 lb) and verঞcal z-axis up to 3300 mm. 8 0 0 • 8 3 5 • 2 5 2 6 buntingmagnetics.com 5 0 0 S . S P E N C E R R O A D / P. O . B O X 4 6 8 / N E W T O N , K A N S A S 6 7 1 1 4 - 0 4 6 8 D e s i g n e d M a n u f a c t u r e d I n T h e U S A . See It At NPE Booth #W5563 The high heat requirements in today's plastic molding or extrusion applications are met with Bunting's new FF350 Drawer Magnet. It's rated to 350 0 F, hotter than any other drawer magnet on the market. How can it take the heat? • High temperature compensated rare earth magnets for stronger hold • Temperature-resistant viewing window • Higher temperature rated seals and knobs • Fits the standard FF housing, so you can upgrade existing equipment with high temp components When you need to turn up the heat, call Bunting. Performance that turns up the heat. Introducing The FF350 Drawer Magnet, Rated To 350 0 F. 34

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