Yarn Technology
Textile World Asia Special ReportWinding Made EasyProperly laid yarn, careful handling of the
yarn on the package surface and optimum package structure are some touted advantages of the
Autoconer 338 winder.
At the ITM 2004 International Exhibition of Textile Machinery, held recently in Turkey,
Schlafhorst, a subsidiary of Germany-based Saurer GmbH & Co. KG, highlighted among other
technologies its Autoconer 338 yarn winder. According to Schlafhorst, the Autoconer 338 is highly
popular in the Turkish market, with several thousand units already installed.With the Autoconer 338
product family, the textile industry has a technology that is capable of efficiently winding yarn
for any application, according to the company. The winder’s modular platform makes automatic yarn
package winding economically efficient. Additional performance features — which include advanced
monitoring and operating systems, and intelligent closed-loop control systems — ensure package
quality and efficiency.One System, Many Package FormatsThe Autoconer 338 produces yarn packages in
various formats to meet the diverse production requirements downstream of winding. Conical and
tapered packages with a 3-inch to 6- inch yarn-guide traverse are wound tightly with large
diameters for warping and weaving, loosely for package dyeing, or waxed with increasing taper for
knitting.With the Autotense FX and Propack FX modules, the Autoconer 338 has two control systems to
optimize yarn tension and contact pressure, which affect the internal structure (yarn laying) and
density — criteria for measuring package quality. Schlafhorst says both the Autotense FX and
Propack FX systems are characterized by continuous, accurate measurement and direct, precise
control, producing packages that are uniform in build, density, diameter and format. Symmetrical
and asymmetrical drum types with different numbers of groove turns are available, ensuring precise
yarn displacement that matches the material to be processed.In cases where power supply is
unreliable, the Quality Cut powerfailure circuit prevents the occurrence of run-out patterns by
lifting and braking the package separately. When processing elastic materials such as elastic core
yarns and Sirospun wool yarns, the characteristic bulging-out of yarn on the package flanks can be
minimized using Schlafhorst’s integrated Variopack FX system.
After a yarn break or bobbin change, the splicing cycle at the winding unit continues as soon
as the presence of the yarn is established, ensuring that only the necessary length of yarn is
unwound from the package.Process-Oriented PackagingEach production process makes particular demands
on the yarn package. The Autoconer 338 permits the winding operator to tailor package formats to
the requirements of downstream processes.Packages can be produced with large diameters and optimal
unwinding properties for warping and weaving applications. For example, the Propack FX system can
help avoid the diameter limitations that result from critical pattern zones. Highly precise length
measurement guarantees a uniform package run-out in warping, thus reducing waste considerably.For
knitting packages, the constant yarn tension generated by the Autotense FX forms the basis for an
even level of waxing. Specific yarn tension settings ensure a constant low-wax application, which
is operational in the optimum range of the waxing curve. An optional wax-monitoring system issues
early warnings before the wax roll runs out and guarantees that no unwaxed yarn will run onto the
package.The identical package diameter and yarn tension of the Autoconer 338 packages, along with
their precisely measured running lengths, are key to producing high-quality plied yarns.These
packages can be used directly for twisting or assembly winding. When winding dye packages, the
Propack FX, Autotense FX and central setting of the winding parameters allow for low, uniform
package densities to be reproduced repeatedly. In addition, the Autoconer 338 can produce dye
packages with particular densities by centrally adjusting the yarn tension on the Informator,
yielding packages that give consistent, reproducible dyeing results. In certain cases, the optimum
package build makes it possible to use dyed packages directly in warping and weaving without
rewinding.
The Autoconer 338 allows yarn packages to be tailor-formatted to the requirements of
downstream processes.Gentle Yarn Handling,And Safe, Reliable WindingHigh process reliability and
package quality are ensured by the coordination of process sequence functions and the optimal
arrangement in the yarn path of various parts, including winding unit control, yarnguide- drum
direct drive, package soft start-up, standard electronic antipatterning, and package lift-off after
a clearer cut or yarn break. The results are gentle yarn handling and a safe, controlled
productionprocess.Schlafhorst uses state-of-the-art sensor technology to monitor the winding
process, which results in intelligent regulation, short piecing cycles and the elimination of
unnecessary additional cycles. The unique upper yarn sensor and vacuum-controlled suction system
create a package built with gentle yarn handling. The low vacuum level can be set specifically for
the yarn, and together with short search and suction times in the area of the upper yarn, this
guarantees gentle handling of the package surface. Roughening of the surface caused by intense
suction is avoided by the lifting of the package each time there is a yarn break or clearer cut, as
the drum and package are braked separately. Meanwhile, the upper yarn sensor plays an essential
role in reducing waste. During the splicing cycle, defects are pulled off the package and the upper
yarn sensor recognizes the presence of the yarn end immediately. After a yarn break or bobbin
change, the splicing cycle at the winding unit continues as soon as the presence of the yarn is
established, ensuring that only the necessary length of yarn is unwound from the package.
Editor’s Note: Heike Scheibe, who is with Schlafhorst’s Autoconer marketing department,
provided this article. The original manuscript has been edited for space and clarity.
Fall 2004