EQUIPMENT NEWS
Moulding machines tout process stability and productivity
 |
Process stability and productivity are the hallmarks of electric injection moulding machines that are now available with lubrication systems and lubricants that comply with US FDA requirements. B-series moulding systems from Fanuc Robotics Deutschland GmbH (Neuhausen a. d. F., Germany; www.fanucrobotics.de) incorporate CNC technology for precise results, servo drives for speed, artificial intelligence and tool protection, and ultra-thin-wall moulding capabilities.
The company’s development engineers have increased the horizontal distance between the tie bars to accommodate larger tools. This also improves stiffness for the use of heavier and more complex moulds.
Fanuc relies on two-platen technology on the movable side. This generates a uniform clamping force on the tool, which is desirable for the mass production of small precision parts using multicavity tooling.
Other features include injection speeds that can attain 700 mm per second and the expansive use of artificial intelligence. The AI pressure-profile trace control, for example, traces the recorded pressure profile on the optimal moulded part to enable enhanced repeatability and precision. The machines also feature AI metering control.
Company offers affordable cleanroom moulding system
 |
A cleanroom production cell equipped with a sterile packaging unit is described as an inexpensive alternative to conventional-controlled environment systems. Developed by maker of injection moulding machines Dr. Boy GmbH & Co. KG (Neustadt-Fernthal, Germany; www.dr-boy.de) and cleanroom builder Max Peter Reinraumtechnik (Radolfzell, Germany; www.reinraumtechnik.com), the system meets the specifications of a Class 6 cleanroom. The cell has been demonstrated at recent trade shows fabricating infusion bottle catheters.
The moulding machine’s two-platen cantilevered clamping unit and overall design result in a small footprint. To maintain the compact dimensions, the air ionization device, sprue picker, and sterile packaging unit are integrated within the cell.
A Type LMP laminar-flow box is mounted on the machine’s safety gate, sending clean air through the clamping and packaging units. The entire cleanroom sits within the machine’s compact 1.85-sq-m footprint.
The company claims to achieve substantial cost savings compared with traditional cleanroom moulding systems by minimizing the amount of space that is sealed off from the ambient surroundings.
Process control system balances multiple cavity fills
 |
A recently introduced integrated process control system is designed to help moulders achieve a balanced fill in multicavity hot-runner moulds. The TTC-eDAQ 8102 from Gammaflux Europe GmbH (Wiesbaden-Erbenheim, Germany; www.gammaflux.com) combines temperature control technology developed by its engineers with a fill-and-cool system from Priamus (Schaffhausen, Switzerland).
The device uses cavity temperature sensors to detect melt flow characteristics in each mould cavity. Variations in cavity fill times are identified by comparing the temperature curves from each cavity. The unit then automatically adjusts fill times by changing the cavity temperature set points in the TTC temperature controller, causing all of the mould cavities to fill at the same time (or as close as possible).
By enabling the automatic adjustment of viscosity changes, the system balances cavity fill times and minimizes part variations on multicavity moulds, according to Gammaflux. Other reported benefits include improved part quality and consistency, and enhanced tooling performance.
In related news, Priamus has developed a Pass Controller to help moulders achieve consistent results across machines, moulds, and production locations. Designed to monitor and control injection moulding operations, the compact device associates such features as maximum cavity pressure and temperature with the moulded parts. Melt viscosity is also determined by cycle and monitored in between limits. Machine settings are adjusted until the process matches the one that was used at setup, which is visualized by means of a green LED. An automatic switchover option is available.
Vertical moulding machines target productivity
Vertical moulding equipment designed by OMF Turra (Grumello del Monte, BG, Italy; www.omfturra.com) enables users to increase productivity by loading inserts from one of the external tables during the moulding cycle. The company offers a linear table with two half-moulds, a rotary table with an optional number of stations, and a platform that can be moved forward and backward. The Pascal-series moulders ensure that inserts remain stable by keeping mould movement to a minimum.
The firm also offers Cigno-series vertical presses, which are designed to provide flexibility by the use of a bridge structure. This architecture introduces significant space between the moulding columns to fit large moulds or inserts. The base of the rotary table is fitted with vertical platforms. The machines can be fitted with loading and unloading robots and other peripheral units.
Company offers range of cleanroom moulding options
 |
A company with extensive expertise in cleanroom moulding routinely supplies injection moulding machines to suit requirements from customers in medical manufacturing. The systems range from machines installed within a cleanroom to cells with contamination-control modules above the clamping area and robotic system. As one example, Arburg (Lossburg, Germany; www.arburg.com) cites the Allrounder 270 U, which is being used to mould stopcock valves for a medical device.
Made from ABS, the valve weighs 0.872 g. The injection moulder is equipped with a horizontal Multilift H and an eight-cavity mould. The cycle time is 9 seconds.
The clamping unit and operating area of the Multilift robotic system have individual clean-air modules. The valves are placed on a conveyor belt, which is also fully encapsulated, and transported to a decentralized cleanroom, where the parts undergo further processing.
Arburg’s Allrounder machine includes a position-regulated screw, an electromechanical dosage drive, and energy-saving mechanisms. As a result, the machine features precise dosing, low energy consumption, short cycle times, and high process reproducibility. Special cleanroom features include a water-cooled motor and cleanroom modules with category 3 ionization. The Allrounder machines have a smooth, scratch-resistant powder coating and 100-mm ground clearance to facilitate cleaning of the floor under the machine.
Electric machine moulds hearing-aid housings
 |
An all-electric moulding machine with a 500-kN clamping force and a size-55 injection unit produces technical parts in a single-cavity mould at a cycle time of 22 seconds. The components—the lower halves of hearing-aid housings—are made from ABS with a 6-g shot weight. Ferromatik Milacron (Malterdingen, Germany; www.ferromatik.com) announced that it would exhibit the Elektra Evolution 50 machine at the Swiss Plastics show in Lucerne in mid-January 2008.
The machine on display is equipped with a water temperature control unit from the Italian firm Moretto and a gravimetric colour-dosing unit from US-based Maguire. A robot with destacking equipment from Swedish firm Wemo removes the parts and places them on a conveyor belt.
The company currently has available eight machines, with clamping forces from 300 to 3000 kN. Its newest model, the Evolution 230, with a clamping force of 2300 kN, was introduced at the K show in Düsseldorf in October 2007. It is designed to fill the gap between the 1800- and 3000-kN clamping forces, according to the firm.
Technical University of Munich develops microinjection moulding machine
Rising demand from the med-tech industry for very small high-precision moulded parts prompted the faculty of medical technology at the Technical University of Munich in Germany to develop a microinjection moulding machine. Begun in March 2005, the project reached a major milestone in October 2007, when a working prototype was presented at the K show in Dusseldorf, Germany. Commercialization is planned in the near future, once further refinements have been incorporated, says faculty member Daniel Ammer.
“Medical-grade materials are expensive,” says Ammer. “Our goal in developing this equipment was to find a way to avoid wasting this material.” Conventional moulding units require high shot volumes to produce small components, he explains. Moreover, the amount of time the material rests during the moulding process can lead to thermally caused material damage. Researchers and students working on the project combined eXtreme Fast Control and servo-electric drive technologies to create a suitable injection process.
PC-based control technology from Beckhoff Automation GmbH (Verl, Germany; www.beckhoff.com) is used to achieve real-time control and sequencing of the machine. Because the micromoulder must operate repeatably and with extreme precision, short reaction times and high sampling rates are required from the controller. This is where XFC technology comes in. The technology is based on an optimized control and communication architecture comprising an advanced industrial PC, ultrafast I/O terminals with extended real-time characteristics, EtherCAT high-speed Ethernet fieldbus, and TwinCAT automation software. The use of XFC components achieves such a high rate of reproducibility, according to Ammer, that the faculty’s micromoulder did not require a special dosing axis, which is generally mandatory in conventional microinjection moulding units.
