EoW July 2007

english technology news

Production line for sheathing high voltage cables

The specifications for high voltage cable require a special cable design. The cable core of such cables can be provided with a metallic sheath (aluminium, copper, steel or even their alloys) in a very high stability. The metal sheath with helical corrugation is water and gas tight and ensures flexibility, as well as high impact and pressure stability. Nexans has developed its UNIversal WElding machine (UNIWEMA®). For sheathing of high voltage cables the UNIWEMA® 200 is best suitable in the core diameter range of 45-200mm. The sheath can be applied continuously with, for instance, aluminium of approx. 0.5-2.5mm wall thickness, depending on the cable core diameter in a very economic process compared to the conventional extrusion or press technology. In the UNIWEMA® process, a metal strip is introduced into the machine and, in a single operation, the strip edges are trimmed and formed around a cable core. The opposing strip edges are welded with the TIG (Tungsten Inert Gas) welding method. The standard UNIWEMA® is equipped with a single electrode. In case of applications where the maximum allowable welding current with one electrode is insufficient (eg for thicker strips or if higher speeds are desired) the UNIWEMA® can also be operated with a 3-electrode welding torch system, Polyarc welder. For fully continuous TIG welding, Nexans has developed a new system called TwinTorch® which consists of two torches, control programme and two welding rectifiers. High-speed ultrasonic wire cleaning GEO-Reinigungstechnik (GEO), Germany, offers tailor-made surface cleaning solutions for continuous line profiles. Due to a patented high-performance ultrasonic cleaning method, the surfaces of wires and tapes can be cleaned in-line at high-processing speeds and within confined spaces. The company’s product range is enhanced through the brush and high-

On the production line

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Nexans Deutschland Industries GmbH & Co KG – Germany Fax : +49 511 676 3777 Email : uniwema.tech@nexans.com Website : www.nexans.de New to the range Cemsa, Italy, has recently produced a new machine belonging to the GRG–NT-3PH series, which is designed for the production of gratings for walking surfaces or for protection fencings, and for the production of panels for stairs or gangways. Cemsa – Italy sonotrodes by redirection. Designed to user specifications, the water treatment units are separated and easy to access. For all its lines, GEO uses specially designed high-pressure water rinsing and ultra efficient air wiping that can also be purchased by itself or added to existing lines. These particular features can be used on single-wire or multi-wire lines. GEO-Reinigungstechnik GmbH – Germany Fax : +49 25429 29791 Email : info@geo-reinigungstechnik.de Website : www.geo-reinigungstechnik.de Fax : +39 022533307 Email : info@cemsa.it Website : www.cemsa.it

If the worn out electrode has to be changed the PLC controlled process will ignite the second torch. The worn out electrode can then be exchanged easily. The TwinTorch® technology ensures an uninterrupted, high quality welding seam without any welding defects. A split clamp caterpillar capstan located downstream from the welding station pulls the sheathed cable through the machine and, if added flexibility is desired, pushes it to the corrugation unit. The perfect coordination of the forming and welding operations with the split clamp caterpillar capstan is a precondition for obtaining a uniform welded seam, thus ensuring optimum product quality. pressure cleaning processes, which offer solutions for many applications. GEO has recently supplied a high speed cleaning unit as part of a multi-level steel wire cleaning and processing system to a French customer. The machine is designed for speeds up to 10m/sec. Cleaning, rinsing and drying are integrated in a stable casing of 4.30m long. To increase the contact time with the ultrasound, the wire is guided three times through a pair of ultrasonic

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EuroWire – July 2007