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INJECTION MOLDING At next month's Fakuma show in Friedrichshafen, Germany, HRSflow of Italy (U.S. office in Byron Center, Mich.) will show off a new family of screw-in hot-runner nozzles for small, delicate parts such as loudspeaker grilles and for reverse gating from the ejector side. Thanks to a space-saving heating system, the nozzle-seat diameter has been reduced from 33 to 28 mm over the entire length. Nozzle lengths range from 75 to 450 mm with internal diameters of 6, 8, and 10 mm. They are offered with one or two heating zones and in Classic Line and Fail Safe versions—the latter with two heaters and thermocouples. Gating options include torpedo, free-flow, and valve gating. 855-477-3569 • hrsflow.com New Compact Hot-Runner Nozzles Debut at Fakuma Show Two-Layer Light-Barrier Preforms For PET Milk Bottles At the Drinktec beverage technology show this month in Munich, Germany, Netstal (U.S. office in Florence, Ky.) will present two-layer Prelactia light-barrier PET preforms for milk products and drinks with a long shelf-life (up to six months for milk). These preforms consist of a 1-mm inner layer of gray PET, which is overmolded with a 1.4-mm white outer skin. This approach is said to provide an improved light barrier—blocking nearly 100% of visible light—while cutting the use of expensive, UV-blocking titanium dioxide white pigment by two-thirds. The molding system is a Netstal PET-Line 2400- 4000/1000 240-metric-ton hybrid machine with two-stage screw/plunger injection and a second injector in an "L" position. The side injector first molds the gray inner layer, then the main injector overmolds the white outer skin. At the show, the 32 + 32 cavity mold for 17-g, 0.5L preforms will by supplied by Molmasa of Spain. The core plate shuttles up and down to transfer preforms between the two molding stations. A top-entry robot removes the preforms to a post- cooling station above the clamp. A second robot transfers the cooled preforms to a belt conveyor that carries them down to floor level. Overall cycle time is 9 sec. 859-283-0200 • kraussmaffeigroup.us INJECTION MOLDING INJECTION MOLDING Suction-Cup Vacuum Monitoring Helps Robots Keep Their Grip Adjustable vacuum monitoring for suction cups is a new standard feature on W8 series robots from Wittmann Battenfeld, Torrington, Conn. Wear on suction cups and leaks at connection points of vacuum hoses can weaken the robot's grip on molded parts, poten- tially leading to a part left in the mold or dropped prematurely by the robot. Such potentially costly errors can be prevented by means of a new early- warning vacuum-monitoring function that can be programmed into the R8 control system on W8 series robots. The controller already lets users program individual vacuum levels for each individual suction circuit; now it's also possible to program a warning level that alerts the user to weaker vacuum before it gets to the point where the robot is unable to grip the part. That level has to be set by trial and error, since it depends on the part shape and surface texture. In accordance with the color-coded operating-status lights on Wittmann robots, the vacuum-level display shows green for adequate vacuum, yellow when vacuum falls into the warning zone, and red, when vacuum is too low to hold the part. With this feature, users are prompted to perform maintenance checks before an operating failure occurs. 860-496-9603 • wittmann-group.com Suction Cup Monitoring Pressure Suction fatigue pressure level 1 atm/ 100% Part lost 0% Time 62 SEPTEMBER 2017 Plastics Technology PTonline.com With Technology Keeping Up