Coperion: Polyolefin extruders - Increased torque and new model ZSK 420

At K 2010 in Duesseldorf Coperion GmbH (formerly Werner & Pfleiderer) featured two further developments of its high capacity extruders for the compounding of polyolefins. The specific torque of the ZSK MEGAcompounders with screw diameters of 177 mm and over has been increased from 11.3 to 12.5 Nm/cm³. In addition, a new model, the ZSK 420 for products with high volume or degassing requirements, is ready for the market.

ZSK MEGAcompounder: the advance to the 100 tonnes per hour barrier
The increased specific torque of 12.5 Nm/cm³ extends the polyolefin compounding potential of the ZSK MEGAcompounder series considerably. In particular, it permits a further increase in what are the three most important criteria: maximum throughput, greatest possible efficiency and highest product quality. Production capacity will be as high as
• 100 tonnes/hour for LLDPE and HDPE,
• 90 tonnes/hour for PP and
• 80 tonnes/hour for LDPE.
Thus, the 100 tonnes per hour mark for polyolefin compounding is now well within reach. Moreover, the increased specific torque also permits a reduction in the energy required for the compounding process, as the more powerful drive increases the degree of fill in the screw flights and this in turn reduces the average shearing of the melt and the specific energy input. The specific energy costs go down, while the reduced temperature stress on the melt improves the product quality.