High torque as key concept

Newly launched extruders are designed to combine high performance extrusion with increased throughput. At K 2013 in Düsseldorf, several extruders were introduced into the global market promising greater efficiency in today’s highly competitive environment.

The Infrastructure Division of battenfeld-cincinnati (www.battenfeld-cincinnati.com) offers a high-torque drive concept with its solEX GL (GL = gearless) single screw extruder series. The system presents an alternative drive concept without gears. Instead, a frequency-controlled, high-torque AC motor is used to drive the screw, with the screw and the motor’s output shaft forming a single line. Both the motor itself and the frequency converter are water-cooled. The extremely smooth running of the motor ensures vibration-free extrusion with a low noise level even at high screw speeds. The high-torque AC motor has a high degree of efficiencyiatiallilevelsi–ieveniunderipartiali load. Since the drive of the solEX GL series operates without gears, all those energy losses caused by any gear transmission system,isuchiasifiangeilossioriheating,iarei also eliminated.

Due to its higher degree of efficiency, the water-cooled, high-torque AC motor shows a higher energy efficiency than the combination of a gear transmission system with an AC motor, which is normally used. This is why the solEX GL extruder ranks amongst the most economical machines in its class in terms of energy consumption. Thanks to the use of high-torque motors, solEX GL extruders are equally attractive due to their small footprint and easy maintenance

Another company, KraussMaffeiBerstorff (www.kraussmaffeiberstorff.com) introduced its KME 60-41 B/R at K 2013. The machine represents the latest single-screw extruder series with, at a processing length of 41L/D, is considered the longest processing unit. The exhibit was combined with the KM-RKW 34-250 IPC pipehead. With its actual processing length of 41L/ D, the new series is ideally suited to high-performance PE- and PP-pipe extrusion. “When we were redeveloping this series, we incorporated elements from our 36D series, which has enjoyed significant success for some time and boasts customers from across the globe, and combined these elements with a new processing concept,” according to Peter Roos, President of the Extrusion Technology segment of the KraussMaffei Berstorff brand. “True to our motto ‘Lengths in front’, the new series, with its patented processing concept and 41L/D screw, delivers a disproportionately increased throughput, and at the same time maintaining low melt temperatures and high product quality,” Roos stressed. The consistently high outputs and unfailingly excellent product quality that result from this pay dividends for extrusion shops.

The screw has been designed to exploit the entire length for melting and homogenising. This reduces the amount of stress to which the polymer is subjected, as well as ensuring that plasticisation has a reduced impact on the material properties during the melting process. In addition, an improved combination of heating and cooling means that the barrel can ensure optimal heat dissipation. A filling opening that has been modified in terms of length and dimensions to accommodate the increased throughput guarantees linear throughput development across the entire speed range. The design of the spiral grooved bush provides low-impact material handling alongside feed stability. Long machine life is implicit in the new extruder series, with bi-metal barrels and optionally through-hardened grooved bushes imparting excellent wear-resistant propeNike Zoom Flight Bonafide