EoW November 2010

technology news

Wire and rod dry cleaning Advertorial on behalf of Decalub

Dust-free powder coats Rolf Schlicht’s electrostatic powder coating machine, model RSC, is designed for an even, finely dosable and dust-free powdering of cables and wires with powders such as talc and swellable powder. Machines are available for product diameters up to 200mm. Electrostatic charging of the powder gives an even and strongly adhered layer on the product surface. The electrostatic charge ensures that no powder will fall outside the dusting chamber. The company also supplies machines with two or four powder nozzles, depending on the application.

Decalub’s development of wire and rod Smooth-Brush (SB) system by ultra-fine brushing replaces the most costly operations in wire drawing process, including acid and wet pre-coating chemicals, providing substantial cost savings, environmental benefits and productivity improvements. TheSB systemfeatures in-line smooth ultra-fine brushing at no speed limitation providing an extra-clean wire rod of white metal appearance, performing: (a)

Wire and rod cleaning by SB brushing system ▲ ▲

Successful test of HVDC power transmission system The SB system is suitable for use where the surface finish is of great importance. The system offers consistency and can benefit demanding applications including plating wire, cold-heading wire and H/C wire where the ductility is a focus, particularly in the production of spring wire, bead wire and PC strand wire. Decalub – France Fax : +33 1 6020 2021 Email : info@decalub.com Website : www.decalub.com drawn wire cleaning/polishing for metallic (Zn, Al, Cu) and plastic coating applications, and (b): providing rod surface specific morphology by micro-abrasion, adjustable at will up to 15 microns, which is ideal for in-line dry coating/lubrication and direct drawing of mechanically descaled H/C and L/C rod (including 0.90 %C ). The system provides an extra-clean product by transversal high-speed ultra-fine brushing all around the wire/rod circumference with automatically controlled brush pressure, adjustable at will, and ensures unchanged rod/wire physical properties with no residual stress induced, operating virtually at zero consumables cost (one set of brush inserts cleans 100–120 tonnes of wire rod).

A prototype HVDC HTS cable together with a termination was subjected to a series of tests according to CIGRE (International Council on Large Electric Systems) test recommendations. They included testing at a voltage of 360kV, representing 1.8 times the 200kV opera- ting voltage, over several hours. The system was subjected to superimposed over-voltages such as those occurring during lightning or switching events. The HVDC HTS cable is based on a similar configuration to the 138kV alternating current (AC) HTS cable currently operating in Long Island in the US. The termination (connecting the cable to the electrical network) is different from that used in AC systems. Nexans – France Fax : +33 15669 8484 Email : nexans.web@nexans.com Website : www.nexans.com

After having qualified a high voltage (HV) cross-linked polyethylene (XLPE) cable system for direct current (DC) appli- cations, Nexans is enlarging its tech- nology portfolio for this growing market by developing a DC superconductor cable system operating at 200kV. Such superconducting cables are expected to provide the most efficient transmission systems for gigawatts of power. Nexans has announced the successful test of the world’s first HVDC high temperature superconductor (HTS) power transmission cable designed for 200kV. This is an important step in demonstrating the capability of underground HVDC HTS cables to transfer bulk power at the gigawatt levels required by proposed supergrid projects such as the Tres Amigas renewable energy market hub in the US. The voltage tests were carried out at the Nexans high voltage laboratory in Hanover, Germany.

Model RSC electrostatic powder coating machine ▲ ▲

The machine features a fluidised powder hopper from which the powder 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. Depending on the product the powder gun can be equipped with different powder nozzles. A fine dosing device is also available. RSC is fitted with a fully automatic and maintenance-free filter system that maintains a strong, constant vacuum in the machine. Inlet and outlet openings of the dusting chamber do not need sealing brushes. Rolf Schlicht GmbH – Germany Fax : +49 40 67 99 4211

Email : info@schlicht-gmbh.de Website : www.schlicht-gmbh.de

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EuroWire – November 2010