Cutting in action

4 mins read

High speed aluminium cutting, high productivity tube sawing, and a "revolutionary" bandsawing development – Andrew Allcock gets the low-down on latest applications and technology

Leading supplier of metals to the aerospace industry in the UK, Wilsons Ltd, Huntingdon, has invested in three high-speed, automatic bandsawing machines from KASTO (01489 772882) in the past five years. The latest saw to be installed is a dedicated aluminium-cutting machine, KASTOtec AM4. According to Wilsons' director and general manager, James Digby, it is 10 times faster at cutting aluminium alloys than two early KASTO bandsaws installed in the 1980s, which are still in daily use. Founded in 1947, Wilsons currently stocks over 10,000 tons of plate, sheet, bar, tube, pipe, fittings and flanges totalling over 3,000 line items for JIT, Kanban, direct line feed and other forms of supply to customers. Demand is not only for aluminium, which accounts for a majority of turnover, but also for other aerospace metals, including nickel and titanium alloys, and more recently a range of ferrous materials. By 2005, Wilsons had increased its supply of aluminium bar to the UK aerospace industry to the point where its market share had reached nearly 40 per cent. The same year, it decided to branch out into stocking aerospace steels. Additional sawing capacity was clearly needed and, after a brief foray into circular sawing, the company opted to buy a 430 mm capacity KASTOtec AC4 bandsaw. "We asked several different sawing machine suppliers to cut a 203 mm diameter bar of 2014 aluminium. The KASTO machine proved to be by far the quickest. Thankfully, the machine was in stock, as our requirement was urgent at the time, and the saw was operating in our warehouse within three days," recalls Mr Digby. With the advent of steel supply at Huntingdon, the AC4 was naturally deployed onto that work, which curtailed its availability to cut aluminium. So the decision was taken in 2006 to buy a second, slightly larger capacity (530 mm bar diameter) KASTOtec bandsaw, an AC5. This is similarly run at maximum speeds and feeds, predominantly on steel. Even when cutting case-hardened varieties, high productivity rates are achieved. The KASTOtec AM4 aluminium machine was installed in Huntingdon at the end of 2009, in response to increased order levels for aluminium alloys, the result of a growing aerospace market in the UK, despite the recession, and Wilsons having increased its market share. "This machine is finely tuned to cutting aluminium and nothing else, and achieves extraordinarily fast cutting rates, three to four times higher than even the AC4," explains Grant Clay, operations manager. "Downfeed on the AM4 is up to 1.5 m/min, which is progressively slowed automatically by the control the closer the blade gets to the centre of round material, so that the chip load on the teeth remains constant. "When cutting single pieces of flat bar or rafts, the blade goes straight through at a high, constant speed, finishing in less than an hour what would take a day to cut on one of our older saws." Incidentally, the company employs bimetal blades for all its cutting requirements, except on titanium. Image: The KASTOtec AM4 takes just an hour to do what would have taken a day at Wilsons Moving on to recent product developments, RSA (01952 585183) has just unveiled a simple, but effective way to drastically reduce piece costs in tube processing, it claims. Its new sawing centre, RASACUT MXS, achieves in triple cut – depending on workpiece dimensions – an output of up to 11,000 pieces per hour. The RASACUT MXS is designed for tube diameters of 8 up to 20 mm, for triple cut, and 6 to 45 mm for single cut processing. Image: Triple cutting on the RASACUT MXS boost output to up to 11,000 pieces per hour Characteristic of the RSA sawing centres is the modular configuration. The sawing centre can be configured or expanded later by modules for deburring, fixed length measuring, as well as for cleaning and stacking. These modules do not reduce the high sawing performance, however. Kaltenbach (01234 213201) is claiming "remarkable, revolutionary new bandsawing technology, which takes cutting speed and machine performance way beyond any other bandsaw" for the new Behringer HBM400 SC (Speed Cutting) machine. By using new, Speed Cutting technology, the HBM400 SC bandsaw achieves cutting speeds up to 7 times faster than conventional bandsaws when straight-cutting solid metals, up to 400 mm diameter, or 400 by 400 mm in section. Conventional bandsawing machines, for example, will typically cut 150 mm diameter 16MnCr5 material at an output speed of circa 80 cm2/min when using a bimetal blades and take around 150 seconds per cut; or, with a TCT (tungsten-carbide-tipped) blade, will cut at a rate of around 130 cm2/min. The HBM400 SC will make the same cut at 500 cm2/min per cut and take a mere 21 seconds; a dramatic 7-fold gain. The HBM400 SC utilises a specially developed, thinner bandsaw blade, just 1.1 mm thick. This reduces the cutting force per tooth and, importantly, the machine achieves a much narrower kerf of only 1.7 mm, compared to typical industry norms, which enables significant financial savings in waste material and its management. A further evolutionary advance includes enhancement of the proven Behringer servo-feed cutting pressure control system, which ensures constant blade feed, while maintaining precise, optimum cutting pressure, thereby preventing blade overload. This system optimises high speed cutting efficiency and precision, while maximising blade life. Box item The art of fabrication HadFab, a long-standing customer of FICEP (01924 223530), has received a substantial and exciting contract to produce the steelwork for a unique monument in Holland. The company, based in Haddington, near Edinburgh, has many years' experience in producing complete structures, fixtures, fittings and towers for power and telecommunications. It is now utilising this expertise to produce a unique statue, designed by the sculptor Antony Gormley and commissioned by the Dutch government, for the town of Lelystad. Image: Anthony Gormley's Crouching Man, made by HadFab The 25 m high statue, depicting a crouching man, will be completely constructed from steel angle profiles produced by HadFab on a state-of-the-art FICEP HP16T6 CNC angle line. Image: Parts for Crouching Man are produced on a state-of-the-art FICEP HP16T6 CNC angle line This machine was purchased specifically for this contract and now brings the total number of FICEP machines operated by HadFab to four. There are many challenges to be overcome with this complicated structure and Tekla software was used after the initial shape was designed in collaboration with Cambridge University. The model is then detailed in Tekla structures and interfaced with Steel Projects WinSteel to produce machine codes for the FICEP Angle Line. The material is punched, sheared to length by the equipment, and then skilled, labour-intensive shaping of the material is done to form up to 550 nodes consisting of up to 27 angles meeting together to form locating points around the structure. These are to be joined together with longer angles, bolted and welded in position. In total, there will be 4,400 holes punched in the angle profiles and the total weight of the structure will be 60 tonnes. The statue is scheduled to take 18 months to complete.