EoW November 2011

technology news

Custom-made cold weld dies facilitate continuous production

British company PWM, which designs and manufactures high-performance cold welding equipment, is stepping up production of its custom-made dies for welding two different sizes of non-ferrous wire and rod. According to PWM’s managing director, Steve Mepsted, more wire manufacturers are looking for cold welding dies capable of bonding different sizes of wire during the wire drawing process. “We custom make dies specifically for this application, enabling manufacturers to weld different wire sizes together extremely quickly when changing spools,” said Mr Mepsted. “Manufacturers can, for example, weld 2.5mm diameter wire to 2.7mm diameter wire without disrupting production, which has considerable cost benefits.” PWM’s double cavity dies are hand-made by skilled engineers in the company’s own workshops to stringent quality standards using top quality tool steel. Although most of the recent demand is for dies to weld wire sizes with diameters within the range 0.3mm to 1.8mm (0.011"

▲ ▲ Custommade dies from PWM

to 0.071"), PWM has made dies to bond materials with larger diameters, for example 8mm rod to 9.5mm rod. a fast turnaround and can provide custom-made dies within two weeks from receipt of order. Standard sizes of die can be supplied within 24 hours. PWM Ltd – UK Fax : +44 1233 820 591 Email : pwm@btinternet.com Website : www.coldpressurewelding.com PWM offers manufacturers

Rebuilding the North American power transmission infrastructure

As North America prepares to rebuild the crumbling infrastructure and increase the quantity of power transmission lines, decisions need to be made about how to get the power from the generation plants to the places it is required. Overhead transmission lines of 400kV have significant environmental impact. Therefore underground power lines are a preferred option. Underground transmission lines – Milliken cables – are used in high voltage underground transmission when servicing highly populated areas around cities, airports, power generations plants, etc. These conductors’ large cross sections are obtained with a composition of sectors. The pre-spiralled sectors are made separately on rigid stranders, and in a second phase are composed into one large cross section with a drum twisting line. The Milliken conductor is composed with four to seven pre-spiralled compacted sectors. Each sector is separated from the adjacent with insulating or semi-conductive tapes. Frequently, a central round conductor is used and a water blocking tape is placed between the sectors’ layers. Cortinovis has developed rotating machines specifically designed to handle these large conductors: the Cortinovis rigid cage strander with rotating compacting heads, and the Cortinovis drum twister with rotating pay-offs for sector assembly. Cortinovis Machinery America, Inc – USA Fax : +1 908 479 1644 Email : cortinovis@cortinovisamerica.com Website : www.cortinovisamerica.com

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EuroWire – November 2011