What's New at the Show in COMPOUNDING
Compounding machinery news at the K Show next month focuses on more torque, more output, and sometimes both, for kneaders, mixers, and twin-screw extruders. There are also new productivity enhancements for multi-screw and planetary extruders. Other developments promise improved dispersion and degassing for specialty compounds and masterbatches.
News in mixers
Buss AG in Switzerland is introducing a new four-flight, single-screw kneader to compound polyolefin wire and cable compounds and masterbatches. The MX Kneader adds a fourth flight and a fourth row of pins in the barrel to those of the traditional kneader. The flights are also deeper to provide more free volume and have longer flanks for better conveying.
The MX will use a four-motor CMG drive from K & A Knoedler GmbH in Germany (represented here by Henschel America) for screw speeds up to 800 rpm vs. about 300 rpm for the standard kneader. The result is up to two and a half times higher output on an equivalent size machine. The first MX Kneader is being built for the show with 105 mm diam. Both smaller and larger sizes are planned. (Buss first used four flights on its Quantec kneader, introduced at the last K show, which is limited to PVC and powder coatings.)
Farrel Corp. will show its latest 9UM Continuous Mixer, designed for higher throughputs of low-bulk-density materials. Farrel also developed a high-torque version of its size 9 Continuous Mixer (9CM-HT) for rigid PVC. It has 20% more available torque for higher rates and lower temperatures.
For smaller throughputs, Farrel will introduce a new model of its Compact Processor, model CP125 (2 in. diam.), coupled with a single-screw discharge extruder for output of 125 kg/hr (275 lb/hr) of color concentrates and other masterbatches.
For nano-compounding, Drais-werke will show a 5-liter Gelimat mixer modified to disperse nano-fillers. Draiswerke has sold two of the nano-modified Gelimats in the 25-liter size in the past year.
Twin- and multi-screws
Coperion will introduce its ZSK Megavolume Plus, which combines large free volume (screws have a 1.8:1 OD/ID ratio) with significantly higher specific torque (now up to 11.3 Nm/cm3 vs 8.7 previously). Flights are deeper, so there is less shear. Screw speed also can be raised to yield 40% higher throughput of rigid and flexible PVC compounds, Coperion says. The company will show a model with 76 mm screw diam.
Leistritz in Germany is showing upgraded ZSE Maxx corotating twin-screws that combine high torque and high volume. Introduced at K 2004, they have an OD/ID ratio of 1.66:1, thanks to patented asymmetrical splined shafts. Now a new gearbox will add over 30% more torque than on previous models. Leistritz is also building its largest Maxx machine yet, with 135-mm screw diam.
KraussMaffei Berstorff in Germany will display a complete “plug-and-play” twin-screw extrusion system on a skid sized to fit in a standard shipping container. It includes a ZE 50 UTX twin-screw extruder, material-handling auxiliaries, vacuum pump, control cabinet, and underwater pelletizer (from Kreyenborg). The company has offered complete systems on skids for several years, but this is the first time one has been displayed. They’re available for ZE twin-screw extruders from 25 through 130 mm.
Entex Rust & Mitschke GmbH will display photos of two new large planetary-ring extruders. Model 280 has eight large spindles; Model 400 has 14. Entex has built three 280s for compounding and direct extrusion of wood-plastic composites with up to 75% wood. The bigger 400 model is compounding recycled tire rubber for compression molding of mats for cows to sleep on. Entex will also show a TP/WE 70 planetary-ring extruder combined with a gear pump and an underwater pelletizer (from Kreyenborg). This system will be used to demonstrate color changes in 15 to 20 min at the show.
Extricom GmbH (formerly Blach) in Germany will show a new generation of its 12-screw ring extruder with higher throughput capacity. Extricom will also present a new counter-rotating twin-screw vent-port stuffer that is more compact than its previous corotating stuffers.
New peripheral devices
Two companies are introducing pneumatic screen changers. Gneuss Kunststofftechnik GmbH in Germany changed the drives on most sizes of its latest fully automatic SFXmagnus rotary screen changer from hydraulic to pneumatic operation, which reduces cost by about 20%.
Gneuss is also introducing an online viscosimeter with a short, self-cleaning polymer bypass. It monitors and displays viscosity, shear rate, temperature, and pressure.
Xaloy Extrusion will introduce a new XP manual screen changer with compressed-air assist to index the slide plate. It’s available for 60- to 120-mm extruders. Xaloy will also show a new integrated set-up of a continuous screen changer with a melt pump.
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