TPT March 2014

Technology News

Aluminium round and PFC tubing

BWE Conform lines in production for PFC and round aluminium tubes

the non-ferrous, cable and tube industries. Typical applications include copper and aluminium rectangular wire (magnet wire for transformers), solid aluminium conductor (SAC for cables), copper bus bar, trolley

PARALLEL flow condenser (PFC), multi port extrusion (MPE), micro-channel and multi-void are all names given to a type of aluminium tube in great demand. These flat aluminium tubes are generally used in the automotive industry for the production of heat exchangers, condensers, evaporators, radiators, oil coolers, heater cores and CO 2 applications. The tubes offer high corrosive resistance, good heat conductivity and high pressure resistance, and are cost effective if extruded from a standard aluminium rod. The tubes are extruded in various different sizes and alloys in accordance with standard specifications and regulations. The automotive industry is continuously seeking and developing more efficient parts to achieve a lighter vehicle and lower CO 2 emissions. Aluminium round and PFC tubing are playing a large part in achieving these goals. BWE Ltd is a British engineering company specialising in continuous extrusion machines (Conform™ and Conklad™) and cold pressure welders for many different applications. Conform and Conklad are established continuous extrusion technologies in

production efficiency has improved. A reduced pre-heat time and a constant high temperature are possible, which in turn reduce the risk of thermal damage to the delicate and complex mandrel during start-up. TheConformprocess offers lowcapital and running costs, high output, high product quality and short changeover times. The product has excellent surface finish, high dimensional tolerances and fine, even grain structure. Conform is a continuous extrusion process and has very stable running conditions, enabling the mechanical properties of the product to remain consistent, with no variation along its length.

wire and other shaped conductors, AS wire, OPGW, CATV, round refrigeration tube and multi-channel PFC tubes in different alloys. A new Conform S315i model has been specifically designed to extrude either a round or multi-channel PFC tube from the same aluminium rod (9.5mm, 12mm or 15mm diameter). One customer purchased a total of ten lines from BWE specifically for this application. With simple tool changes, the same machine is capable of extruding solid aluminium or copper conductors, making it a very flexible machine. BWE has production experience of a wide range of PFC sizes (10 to 105mm), hole shapes (round, square, triangular, with internal fins), and alloys (1000 series, 3000 series and special alloys). With the introduction of the company’s Induction Heated Tooling System,

BWE Ltd – UK Fax: +44 1233 630670 Email: mail@bwe.co.uk Website: www.bwe.co.uk

FEM analysis opens possibilities of cold roll forming

forming loads into high accuracy data. Optimised mechanical structure is designed by applying FEM structural analysis based on the data. Nakata’s know-how is incorporated in creating high rigidity cross beam structure for the mills. In the new design, cross beams in the mainframe support forming loads that were traditionally supported by the mill shaft. The new cross beam design achieves high mill rigidity.

during formation. The company built its own roll forming simulation system to accurately predict strip deformation under roll stress, making it possible to optimise the forming process. Nakata developed a forming method using involute curvature rolls (FF rolls) by applying FEM analysis technology. The method not only eliminated roll changes but also minimised influences of diameter, material thickness and steel type while determining the best edge butt shape. The FFX mill can manufacture high grade pipes such as X80 and N80. FEM forming analysis translates

FORMATION of ERW pipe involves complex three-dimensional plastic/ elastic deformations. There is a limit on the understanding of such processes of deformationbehaviours,stressandstrain solely relying on skills of experienced workers. It is also impossible to evaluate a mill design unless actually conducting the forming process. The optimisation of process is difficult for these reasons, requiring many design corrections and modifications after building the mill. Nakata’s proprietary 3D plastic/elastic forming analysis system allows the scientific and theoretical understanding of complex behaviours of steel strip

Nakata Mfg Co Ltd – Japan Fax: +81 6 6303 1905 Email: sales@nakata-mfg.co.jp Website: www.nakata-mfg.com

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M arch 2014