KARL MAYER Textilmaschinenfabrik GmbH
Bühlstrasse 25
63179 Obertshausen
Germany




Available in large, small and now also in medium – the Wefttronic® RS offers even more working widths - KARL MAYER Textilmaschinenfabrik GmbH

For some time now, raschel machines with parallel weft insertion have been among KARL MAYER Malimo’s best-selling machines. They mainly process high-strength polyester yarns to produce straight weft and zero inlays in 90 and 0 layers using three guide bars, and also sometimes two for special applications. The horizontal and vertical load-bearing yarns are fixed in line with the construction by the front guide bars. Products having a high tenacity and tear propagation resistance are mainly produced, and textiles having special characteristics can also be manufactured. The weft-inserted fabrics may have dense constructions as well as lattice constructions with specific opening widths, and can have a range of weights from light- to medium- weight – depending on the requirements of the end-use. The main end-uses of weft-inserted fabrics, which come in a variety of designs, are as advertising substrates and printed grounds, tarpaulins, protective textiles, awnings, abrasive elements and plaster grids. In general, competition is fierce on the markets for stable textiles. Any manufacturer who wants to be successful needs production machines which combine an exceptional price:performance ratio with a high product quality, are easy to operate, and offer a sufficient level of flexibility thanks to their different working widths. These requirements spurred KARL MAYER Malimo on to develop a completely new basic concept for its raschel machines with parallel weft insertion. The result of this extensive development work was the Wefttronic® RS (Fig.). This innovative range was unveiled for the first time at ITMA ASIA + CITME 2010, and its working width has been constantly expanded since then. The modifications in the construction, which led to the development of the Wefttronic® RS, focused mainly on increasing the speed and productivity. Consequently, the entire machine space and basic construction were adapted to the higher dynamics of the warp knitting process in order to increase the speed. In addition to increasing the production speed, the working width was also extended. This enabled the performance to be increased by up to 20%. Another improvement in efficiency offered by the new weft-insertion machine has been achieved by improving the components used in weft insertion. For example, the guide system of the circulating chain has been re-designed, and the weft insertion system has been optimised. The weft carriage now contains 30 yarns instead of the previous 24. The modified weft insertion system, with its ½-inch spacing, also guarantees fault-free yarn laying without the yarns sticking together, which also increases the product quality. In order to produce a perfect textile, the entire yarn handling sequence on the machine was analysed and improved. These changes in the construction resulted in uniform zero inlay run-ins in the delivery unit and at the guide rollers, thanks to central supports and short yarn paths for the knitting yarns in the ground guide bars. The recent developments have concentrated on complementing the range of working widths available. Whereas the first Wefttronic® machine, which appeared in 2010, had a width of 268", a version having a width of 138" was already available for ShanghaiTex 2011. A Wefttronic® RS in a width of 213" was being exhibited at ITMA Asia 2012. This intermediate width is complemented by a machine having a width of 176”, which was launched at the same time. The different working widths of the Wefttronic® RS for the simultaneous production of several fabric webs next to each other can be fully utilised to achieve a high level of operating efficiency.