Elastane yarns give garments stretch and a perfect fit, but they do present a number of production challenges.
During warp preparation in particular, the special physical characteristics of the high-stretch synthetic yarns have to be considered. The capacity of the yarns to stretch by as much as 700% demands that they be processed without any friction points, if possible. Friction points cause uncontrolled distortion, which results in uneven dyeings.
For this reason, the yarn tension and stretch have to be monitored and adjusted constantly when processing elastane yarns during warp preparation – a requirement that KARL MAYER has successfully met with its DSE-HH direct warping machine. This high-tech machine is proving itself exceptionally well, especially in premium applications, and has now been complemented by a mid-range version to expand the machine series.
This new machine is designated the DSE 21/21 EC. It has an excellent price:performance ratio, which is ideally suited to the commodity business. This new direct warping machine, with the emphasis on practicality, complements the DSE-HH at the highest technical level and forms part of KARL MAYER’s successful twin product line strategy.
A comparison between the high-tech and the mid-range versions of the direct warping machine
The new DSE-EC is based on the same technical principles as the DSE-HH, but its performance and price have been adapted in comparison with the top-of-the-range model.
One of the main differences between the two direct warping machines lies with control of the cone curve. Cone curve occurs with virtually every bobbin set. It is used to define the different patterns in the bobbin take-off tension between the full and the empty package, and is described by a curve. The difference between the highest and lowest point may be as much as 6%.
It varies from one bobbin set to another and is equalised reliably on the DSE-HH by an automatic cone curve adjustment system. If the manufacturer stipulates the cone curve, the equalising process can be carried out on the basis of the data stored by the producer in the machine. The two processes can also be combined. This also makes the DSE-HH suitable for processing bobbins having unknown patterns of bobbin take-off tension.
If the high-tech sectional warping machine operates with automatic equalisation of the differences in package winding, top-quality elastane warp beams are produced. If the data supplied by the bobbin producer is used as the basis for the warp preparation process, good quality warp beams are produced.
In this case, the characteristics of the beams basically depend on the correlation between the cone curve specified and the actual condition of the winding. This also applies to the DSE-EC. The new price:performance-optimised machine controls the bobbin take-off tension during warp beam production on the basis of the manufacturer’s data alone, and thus also produces good quality products.
Both the DSE-HH and the DSE-EC produce warp beams having a width of 21", but operate at different speeds. Whereas the DSE-HH operates at creel speeds of 400 m/min to produce beams having diameters of 30" and 21", the mid-range version operates at 300 m/min to produce beams having a diameter of 21" only – but at a cost which makes the DSE-EC (in conjunction with its performance) a “must-have”, especially in the commodity business.
Performance features of the DSE-EC
Both the DSE-HH and the DSE-EC operate with automatic layer thickness control. When using this well-thought-out system, a master curve is produced first of all on the basis of the path of travel of a sectional warp beam and the circumference of every subsequent beam is subsequently matched to that of the master curve.
This produces sectional warp beams having the same volume of yarn and circumference in each set. Positively driven bobbins supplying uniform yarn volumes also guarantee a uniform build over the entire width of the beam.
Other features of this new direct warping machine include a computer-controlled braking system for guaranteeing uniform braking paths, reliable and safe stopping of the machine in the event of a power failure, axis-controlled drives with individual motors, and the possibility of activating or deactivating individual creel arms during production. The DC link coupling on the machine also conserves energy. The performance features of the DSE-EC are complemented by its ease of operation, thanks to a touchscreen for selecting the machine functions.
Market launch of the DSE-EC
The first prototypes of this mid-range direct warping machine left the conveyor belts at KARL MAYER in February and March of this year. A total of nine machines have now been built. The DSE-EC was unveiled at ShanghaiTex in June. It has already been released for sale in China and will be available to the rest of the world on 1st January 2014.
