Rieter Com4®rotor Yarn Yarns of Choice Iris Biermann Stephan Weidner-Bohnenberger Rieter Machine Works Ltd. Rieter Ingolstadt GmbH Winterthur, Switzerland Ingolstadt, Germany Rieter Com4®rotor Yarn Guarantee for Success in Downstream Processing

Rieter . Rieter Com4®rotor Yarn

Rieter . Rieter Com4®rotor Yarn Rieter Com4®rotor Yarn – Guarantee for Success in Downstream Processing Com4®rotor yarn is produced on the technologically leading rotor spinning machines from Rieter. It is a successful member of the Com4® yarn family which consists of the four spinning technologies attributable to Rieter. Rotor spinning is the second oldest and second most important spinning process after ring spinning. Rotor spinning owes its market position to its beneficial properties in downstream processing as well as its comparably favourable manufacturing costs. Com4®rotor yarn has distinguished...

Rieter . Rieter Com4®rotor Yarn THE SPECIAL CHARACTER OF COM4®ROTOR YARN The typical structure of rotor yarn is characterized by twisted fibers in the core wrapped around by fibers in the yarn sheath. Some external fibers often form so-called wrapper fibers (Fig. 2). This structure determines the properties of the yarn in downstream processing and also the character of the fabric produced. Com4®rotor yarn exhibits a very even appearance due to its special structure. With a high proportion of short fibers in the raw material, the evenness is even better than with other Com4® yarns. Especially...

Rieter . Rieter Com4®rotor Yarn The more open yarn structure makes fabric from rotor yarn especially suitable for the roughing process, e.g. for household textiles such as blankets or for sweatshirts. Finally, because of its specific properties, Com4®rotor yarn meets a significant proportion of the demand for denim as well as for robust workwear. Rotor yarn is also to be found in home textiles and in technical applications such as the basic element for abrasive cloth. OUTPACING COMPETITION WITH COM4®ROTOR The Com4®rotor yarns, spun on Rieter R 40 or R 60, demonstrate better properties than rotor...

The number of Imperfections and the tenacity served as the primary comparison criteria. With the R 60, these values were quickly reached and even excelled, so that In the second stage with the Com4®rotor yarn, the twist from Alpha English 5.9 could be The result Is clear - the R 60 spin box copes far better with the challenging fiber material. The Com4®rotor yarn shows fewer Imperfections and better tenacity despite a lower twist (Fig. 4). The R 60 offers great potential to produce soft Com4®rotor yarns with a low twist factor. Due to the leading technology of the R 60 spin box, no compromises...

Rieter . Rieter Com4®rotor Yarn MORE EFFICIENCY IN DOWNSTREAM PROCESSING WITH COM4®ROTOR YARN Improved spinning stability means fewer ends down in the spinning process. That again means fewer piecers in the Com4®rotor yarn compared to other rotor yarns. Accordingly, fewer piecers also facilitate better running of the yarn package in downstream processes as even very good piecers are still a potential weakness. This is confirmed by a direct comparison with a customer. Processed was a weft yarn, Ne 16, from 100 % cotton that included 40 % comber noil. The comparison test with a spinning machine...

Rieter . Rieter Com4®rotor Yarn SIGNIFICANTLY LOWER NO OF WEFT YARN BREAKS POTENTIAL FOR COST SAVING IN THE WEAVING PLANT The yarn packages were subsequently used in the weaving facility as weft yarn under the same conditions. The differences in the observed ends down on the weaving machine were surprising (Fig. 6). Per 100 000 weft insertions, the Com4®rotor yarn showed 4 breaks whereas the competitor yarn showed more than 8 breaks. The weft breaks were analyzed during the test. The main reason for the breaks of the yarn from competitor machines was weak piecing. The costs resulting from ends...

Rieter . Rieter Com4®rotor Yarn In the previously described comparison, the weaving plant with Com4®rotor yarn can save more than 1 000 Euro per ton of yarn than with the yarn from the competitor machine. In the knitting plant, similar relations are valid. There also, breaks mean high costs and loss of machine efficiency. DIFFERENCES CLEARLY VISIBLE IN THE LABORATORY That is also decisive for the efficiency in the weaving plant. Normally, a break per 100 000 weft insertions means a loss of efficiency of 1.5 % in the weaving plant (Source: Uster Technology AG, News Bulletin No. 49, November 2012)....

REVEALING WEAKNESS ANALYSIS The weakness analysis with the Uster Tensojet shows the reason for the differences In the weaving plant. Already In the cloud diagram, the lower distribution of tenacity and elongation of the Com4®rotor yarn Is The percentile evaluation further helps to more easily explain the large difference between the yarns (Fig. 9). Percentile evaluation Is creating a mean value from the poorest strength and elongation values. P 1.0 Is the mean value of the 1 % poorest values. The P 1.0 value of the Com4®rotor yarn lies at 12 cN/tex while that of the competitor yarn was 10.3 cN/tex....

Rieter . Rieter Com4®rotor Yarn C0M4®R0T0R YARN WITH INVISIBLE PIECERS Through the modern spin box technology with Its good spinning stability, fewer ends down occur on the R 60 rotor spinning machine than on other machines. To rectify a break, the R 60 uses the most modern AEROpiecing® technology. This produces dependable pfecfngs whose strength and appearance are equal to those of the yarn. Thanks to the easy setting, sup- ported by an expert system In the robot, this quality can be consistently repeated with every piecing. Even when the pfecfngs with AEROpiecing® appear yarn-like, they stILL...

Rieter . Rieter Com4®rotor Yarn VISIBLE PROOF To demonstrate the quality, a special method was applied. During the start-up spinning process, individual bleached fibers were put in the rotor to make the invisible piecings recognizable. If the knitted fabric made from this yarn is examined in daylight, the piecings remain invisible (Fig. 10). Only under ultraviolet light is the position of the piecings visible (Fig. 11). This demonstration is a clear proof that Com4®rotor piecings are not visible in the end product, thanks to AEROpiecing® technology. Fig. 10 Sample with practically invisible AEROpiecing®...