EoW November 2009

technology news

Electrostatic powder coating

Officine Meccaniche di Lesmo manu- factures double twist machines from 400mm to 2,500mm (believed to be the largest in the world). OM Lesmo equipment for power cables includes the drum twister, a bow strander with up to 2,000mm bobbins, a single twist machine for up to 2,000mm bobbins, and a rigid strander for different bobbin sizes. The drum twister handling up to 4,000mm is a very flexible machine for the production of power cables. It can be used for laying-up round insulated conductors for LV and MV from 26mm² to 500mm² and up to 160mm diameter and for LV, MV and HV cables up to 150mm diameter. Stranding of Milliken copper and aluminium conductors up to 3,000mm², screening with copper and aluminium or armouring with steel wires are also possible. Double twist machine The line configuration includes the following components – payoff, pre- heater, NMA 20mm and NMX 12mm extruders, ECH multi-layer crosshead, low flow gas injection group, low drag cooling section, line control and measurement gauges, exit capstan and take-up. Maillefer SA – Switzerland Fax : +41 21 691 2143 Email : info@maillefer.net Website : www.mailleferextrusion.com Microcoax for communication connectivity for com- puters, audiovisual devices and mobile telephony and for device- to-computer applications for signal transmission to medical apparatus, as well as in other special signal transmission systems. As a result, there is an increasing demand for equipment to produce cables with small diameters and thin wall thicknesses. Maillefer designs and delivers TEL 00 lines for the precision production of solid, foam-skin and skin-foam-skin constructions with FEP, PFA or PE polymers. The Extrucell™ physical foaming process makes use of a nitrogen gas injection group specially designed for extremely low flow rates. Microcoax – thin as a human hair cables are used

SOMA’s focus on systems for fine wire drawing, annealing, measuring and rewinding, is expanding to copper bonding wire – viewed as a replacement for gold bonding wire. Price pressure in consumer electronics has driven solutions for copper bond wire in a growing number of chip applications. Copper bonding wire is forecast to replace up to $1billion of gold wire in the next five years. Bare copper bonding wire (of around 20mm diameter) requires a fully annealed final condition, and has stringent criteria for surface quality and negligible oxidation. SOMA’s standard and customised solutions for such copper applications take into account machine design, software, and set-up, which are all critical to the high-speed drawing of copper bonding wire. Wet or dry capstan designs depend on the diameter range. Production is monitored on-line, and machine software can be serviced remotely. Copper bonding wire annealing and spooling are particularly challenging for negligible oxidation, maximum softness, and surface quality preser- vation. High run speed is critical for the best return on floor space and machine investment in any fine wire process step. SOMA’s high-speed PC control systems and annealing oven are designed to provide precise tension control and lowest oxidation. SOMA AG – Switzerland Fax : +41 44 938 9838 Email : info@somafinewire.ch Website : www.somafinewire.ch Serving the copper bonding wire market

Rolf Schlicht's electrostatic powder coater, model RSC, is designed for an even, finely dosable and dust-free powdering of cables and wires of up to 200mm diameter, with powders such as talc, stearate, lac and swellable powder. Due to the electrostatic charging of the powder an even and strongly adhered layer is achieved on the product surface. The electrostatic charge also ensures that no powder falls outside of the dusting chamber. Depending on extrusion speed and product diameter, up to four 100kV guns can be used. The machine features a fluidised powder hopper from which the pow- der is sucked by pneumatic venturi pumps and then blown to the guns. For optimal adjustment of the powder quantity the power of the electrostatic charge can be varied from 0–100kV or the powder nozzles can be changed. A fine dosing device is also available. The machine is fitted with a fully automatic and maintenance-free filter system that maintains a strong and constant vacuum in the machine. Inlet and outlet openings of the dusting chamber do not need sealing with brushes. A free standing dusting chamber is available for use in installations where space is limited; this is connected to the machine by hoses. Rolf Schlicht GmbH – Germany Fax : +49 40 67 99 4211 Email : info@schlicht-gmbh.de Website : www.schlicht-gmbh.de

OM Lesmo SpA – Italy Fax : +39 039 698 1148

Email : omlesmo@omlesmo.com Website : www.omlesmo.com

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EuroWire – November 2009