Amid strong competition, increasing cost of energy and resources and less available space have shaped technology developments. Recent developments by all leading machinery makers in high-speed, low cost extruders mark a quantum leap in extrusion technology. Few of the developments displayed at NPE 2012:
Coperion Corporation exhibited a new ZSK 32 Mc18 intermeshing, co-rotating twin screw extruder that stands out for its specific torque of 18 Nm/c3 and is supported with state-of-the-art processing equipment, with a torque increase of 30% in comparison with its predecessor model and achieves up to 30 % greater throughput rates and therefore ensures maximum productivity. This ZSK Mc18 with 45 mm screw diameter is equipped with a ZS-EG twin screw side devolatilization unit and the Feed Enhancement Technology (FET) on a ZS-B side feeder unit. Also exhibited was its new Horizontal Fluidbed Separator HFS which offers superb fines separation performance, over a wide variety of compounded products, in a compact unit with a small footprint and minimal vertical height requirement. When producing plastic pellets with a pelletizing device, abrasion arises and sometimes geometrical defects of the pellets occur. When the pellets are re-melted for another process, for instance injection moulding or film extrusion, dust or mal-pellets may affect the final product. The HFS solution removes dust or mal-pellets from the bulk materials prior to packaging or processing and that way preserves the high product quality of the end product.
PTi introduced its dryer-less sheet extrusion system, an eco-friendly manufacturing solution, which delivers major energy savings and cost reduction. The production-scale unit, which is capable of processing rates in excess of 900 kg/hr, runs a variety of resins including post-consumer and industrial PET/PLA. The company also presented its new line of winding systems, specifically the company's first three-position turret winder. This is a compact system that allows slit material to be wound two-up (half-slit material can be run on two rolls at the same time). It has a maximum diameter of 40-in, capability for 3 and 6-in cores, a maximum roll weight of 4300 lb, and maximum width of 70-in. This line of sheet winding system also includes cantilever, A-frame, and automatic designs. Fully automated features include cut and transfer, shaft extraction, roll un-loading/core loading, and roll weight measurements and recording. Several of the winders are capable of differential shaft winding, allowing for multiple webs on a single shaft. The winders were initially developed to support PTi's sheet extrusion systems but are also offered as stand-alone products.
Davis-Standard, LLC exhibited a range of its extruder including a groove feed extruder, a new high-speed extruder, a MAC extruder, a direct drive medical extruder and a Super Blue® extruder: A 2-inch (50mm) 34:1 L/D groove feed extruder designed for bimodal PE-100 and other polyolefin materials. This extruder features a low melt temperature, high output design with a new feedscrew for even greater mixing and homogenization. In addition to the 34:1 L/D barrel assembly, this extruder has a 4:1 L/D intense cooled groove feed section.
A 3-inch (75mm) 40:1 L/D high-speed extruder will showcase a high volume feed section and electrically heated/air-cooled system. This extruder is targeted for use with PS and PP resins for sheet and in-line thermoforming. In these applications, a 75 mm high-speed extruder is able to produce the equivalent throughput of a 150 mm machine while still providing excellent melt temperature and pressure stability. The HPE-H Extruder - this adjustable extruder will be shown in a 1-inch (25mm) model with direct drive AC vector motor capabilities and an available Servo option. The compact HPE-H is designed for quick delivery and offers processors high torque capability and an extensive list of options. It will also be used to demonstrate the DS-eTPC touchscreen controller for extruder and line control. A 3 ½-inch (90mm) 30:1 MAC extruder with a slimmer design will be shown. This version of Davis-Standard's high-performance, air-cooled extruder is engineered for nine-layer co-extrusion film arrangements. The MAC is recognized worldwide for excellent rates, improved bubble stability, and excellent gauge uniformity and control. Medical Extruder Direct Drive (MEDD) is a compact new extruder features a direct drive motor for more energy efficient operation. Advantages include linear movement, a replaceable feed section liner, and a Windows® 7 PLC control system. The MEDD also features interchangeable 1-inch (25mm) 24:1 L/D to ¾-inch (19mm) 24:1 L/D barrel assemblies for material versatility.
battenfeld-cincinnati launched three extruder series for pipe and profile applications. The solEX series of 40D single screw extruders serves high performance processing of HDPE and PP pipe. The machines come in five sizes with screw diameters from 45 to 120 mm. Their outstanding feature is the enormous output with low melt temperature. solEX extruders are equipped with a particularly powerful, highly efficient drive train and an optimized processing unit that enable a reduction of energy consumption by about 15%. Extruders from the new series reach such high throughput levels together with excellent melt homogeneity that, compared to conventional 30 D extruders, the next smaller diameter machine model can be used to reach the same performance. The second extruder series to premiere was the twinEX series of parallel twin screw extruders which consist of four machines in sizes from 78 to 135 mm. The extruders require approximately 15% less specific energy input with a simultaneous increase in output compared to other counter rotating twin screw extruders. The machines have already proven themselves repeatedly in the field.