WCA January 2007

Technology News

A quick and easy twist It’s 95 th anniversary celebration time for Eraser, manufacturers of a wide range of industrial products. Eraser’s Model G10S bench wire twister is used for many diverse twisting needs, twisting pre-stripped stranded wires, twisting strands of two or more wires together, twisting wrapped shields on coaxial cables and tightening the twist of already twisted wire. The G10S is supplied with one set of three twist length spacers to vary the twist length, depending on application needs. Twisting inserts can be ordered depending on wire size to be twisted. Eraser – USA Fax : +1 315 454 3090 • Email : lprattico@eraser.com • Website : www.eraser.com

Eraser’s G10S Bench Wire Twister

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New version of kneader for calender feeding Buss AG, Switzerland, has launched a new version of its quantec ® high performance kneader for use in the compounding of high grade PVC pellets for extrusion and injection moulding. The new machine has been optimised for direct feeding to PVC film calenders. Throughput is adjustable in a range of 1 to 3, with improved process stability, and the machine is more compact, saving space and investment cost. A newly developed intermittent cutting device ensures non-adhering PVC pieces of uniform size, and the shut- down time required for opening, cleaning and closing is reduced to between 30 and 50 minutes. Melt quality meets high demands for homogeneity without pinholing, for colour uniformity, and for degassing, all of which are essential requirements for high quality PVC film calendering. The quantec version for calender feeding is a single-stage machine, ie it has no additional discharge screw. Instead, the length L of the mixing and

The new quantec kneader from Buss incorporates a newly developed cutting device to ensure PVC pieces of uniform size ▲

kneading part, normally in the ratio 10 to 11 L/D (where D = screw dia- meter), is extended by 4 to 5 L/D. The additional space serves for degassing the melt and building up the necessary discharge pressure with minimal energy

one or more large cross-section nozzles. It is then divided by a cutter with an innovative control system: the intermittent cutter knife timing is synchronised with the screw motion. As a result, the knives always cut at the beginning or end of each cycle when practically no material is being transported. This ensures a smooth cut, and PVC pieces of uniform size. After cutting, the pieces fall onto a conveyor belt which transports them to the calender roll nip, with enough space between them to prevent sticking together. Individual pieces make for better and more uniform filling of the calender roll nip, which improves PVC film quality.

input. This single stage design offers quality and cost advantages: processing is simpler, and the residence time under thermal and mechanical loading is shorter than with two stage processing. As a result, the sensitive PVC melt is less liable to burn, so process stabiliser consumption can be reduced. At the end of the processing section the finished PVC melt is extruded through

Buss AG – Switzerland Fax : +41 61 825 68 58 Email : info@busscorp.com Website : www.busscorp.com

The quantec kneader for calender feeding features high melt quality, user-friendly handling and easy cleaning ▲

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Wire & Cable ASIA – January/February 2007