WCA November 2013

Keeping up today with tomorrow’s market trends

Cables with smaller dimensions and good electrical conductivity which also have enhanced mechanical properties at the same time (with regard to tensile strength and flexural strength) can be manufactured from copper alloy wire. Signal wiring is increasingly using conductive wires made of copper alloys with higher tensile strength (such as CuMg, CuAg and CuSn). This enables the cable cross section to be reduced from 0.35mm² to 0.13mm². Copper cables with bigger cross sections are increasingly being substituted by aluminium or aluminium alloys in order to save weight and costs. Aluminium wires have already been used for battery cables for some time. Depending on the vehicle manufacturer, the aluminium cables used have cross sections of down to 2.5mm² and in some cases are even used for signal cables. Automotive cable manufacturers are currently researching new types of alloys, among other things, capable of delivering certain mechanical strength and high bending flexural strength under higher temperatures for the engine area, as well as minimising cold creeping. In order to keep up with these trends, the manufacturers of such high quality wires and cables need refned equipment which operates economically and can be used to produce reliably and effciently today’s and tomorrow’s cables. Maschinenfabrik Niehoff has developed machinery adapted to the requirements of wires made of copper, copper alloys, aluminium and aluminium alloys which cover all production steps as well as processing to strands and handling. Some examples are the electronically

The market for wires and associated on-board wiring systems for the trans- port industry is undergoing dramatic change: The number of electric and electronic components used for vehicle operation, safety or comfort is growing, new drive technologies in the automotive sector came in, for which electricity is indispensable, and there is a generally increasing pressure to reduce weight. Where technically feasible, cable manufacturers are researching ways of replacing copper conductors with alternative conductors. The reasons are based on the need to reduce the weight of the cables themselves and the fact that copper prices have been increasing enormously for years. As far as dimensions are concerned, a trend towards smaller wire and cable diameters can be observed. For copper cables the cross sections are limited to 0.35mm², with values as small as 0.13mm² for copper alloys being within practical range. A further reduction to 0.09mm² would also be possible in production terms, but certain elements such as terminations and connections still remain to be certified. Just as wires now have to meet higher requirements, so does the insulation. With a view to reducing outer dia- meters to the minimum possible and taking account of the costs of halogen-free and other high-quality plastics, cables with ultra-reduced insulation wall thicknesses (UTW – ultra thin wall) were introduced, for example of 7 x 0.21mm design and with a conductor cross section of 0.22mm². The insulation on the compacted strand has a wall thickness in the region of 0.15mm. ❍ ❍ The D type double twist buncher from Niehoff

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Wire & Cable ASIA – November/December 2013