WCA September 2012

Technology news

Highest quality wire Wire drawing is one of the major bulk deformation processes to produce high quality wire in a wide cross-section dimension range. During this manufacturing process the cross-section of a wire or rod is reduced by pulling it through a die, located in a special die holder tool. In the multi-pass wire drawing machines the wire goes through several stages of such forming tools. The drawing force for the deformation process is mainly influenced by the geometry of the die. For the evaluation of the die geometry the delta factor is used to predict the optimum approach angle. For the reduction of wear and friction and to achieve high surface quality, optimal hydrodynamic lubrication is important. The Linnox drawing machine by CPA is designed as a wet drawing machine for fine high-strength steel wire and operates on the principle of the so-called slip drawing process. Implementation of modern technological aspects ensures the production of highest wire quality. High pressure cooling lubricant jets in the deformation zones protect against metal dust, provide an intense heat removal directly at the forming area and guarantee an optimum lubrication of the drawing tools. Another advantage is the high operating comfort with an integrated control system.

❍ ❍ Increased flexibility from Rosendahl

For many years it has been popular to shield MV, HV and EHV cables with lead or aluminium or with longitudinal applied glued Al/PE tapes. Based on the growing market demand for alternative solutions for these, Rosendahl Austria has entered this segment of power cable manufacturing equipment. Rosendahl’s metal tape forming and welding line RN-W gives the possibility to produce cables with better properties like increased mechanical stability, water and/or gas tightness, high-pressure resistance, lower weights, smaller dimensions and short current resistance. At the same time this technology is more environmentally friendly and more flexible. The metal sheathing process starts with a tape out of copper, aluminium or stainless steel, which will be applied around a cable core. These tapes will be formed, longitudinal welded and sized. Depending on the requested product design a corrugation process can follow. An advantage of this solution is the possibility to fulfil plenty of different demands (cable designs) with high productivity. In addition to this it is possible to have an “offline” or an “inline” (combination with the jacketing process) configuration. Metal tape forming with longitudinal welding gives cable designers and makers the possibility to serve solutions to the market, especially in the field of renewable power generation and transport. The target is to serve lighter cables, which fulfil all requirements and specifications. At the same time these cables offer increased flexibility and cross pressure resistance. In the field of land-cables Rosendahl’s RN-W presents an innovative alternative to the commonly known “combined layer technology” where, for example, screen wires and tapes are used. RN-W for MV, HV & EHV power cables Metal tape forming and welding line

CPA – Austria

Website : www.cpa.at

Rosendahl Maschinen GmbH – Austria Website : www.rosendahlaustria.com

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Wire & Cable ASIA – September/October 2012

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