Hollow-Spindle Spinning Process of Yarn Manufacturing

Hollow-Spindle Spinning:

In this process, a yarn twist is replaced by wrapping a filament binder around the main fiber materials used (Figure 1). This results in an impressed yarn structure where most of the main fibers/yarns run parallel to each other along the strand axis, while the filament binder provides the necessary cohesion. Despite the striking similarities, yarns made using the hollow-spindle system are quite different from those made by the conventional ring-spinning system. They may also differ in details of appearance and behavior during processing. Hollow-spindle yarns are mainly used in woven garments or fabrics, although plain yarns have found many other applications such as carpets and medical textiles. When used in the production of fancy yarns, the hollow-spindle technique incorporates the binder and produces an immediate effect rather than using a separate second operation. In yarns produced on hollow spindles, the fancy yarn has no twist to hold the core fibers/yarns together, so there is no cohesion beyond that provided by the binder. When the binder breaks down, the core fibers separate more freely and dramatically in the case of fancy yarns produced by ring-spinning systems. Figure 8.23 shows the schematic of the hollow-spindle system. In this particular example, there are four independent feeding devices, three for the effect fibers and one for the main yarn. The effect fiber is fed in the form of main rovings or slivers. The fibers are then formed using a roller drafting system such as a ring frame. The effect fibers meet the main yarn and then pass through the rotating hollow spindle. A bobbin carrying the binder, usually a filament yarn, is mounted on the hollow spindle and rotates with it. The binder yarn is drawn from the top onto the hollow spindle. The rotation of the hollow spindle wraps the binder around the main strand and main yarn. The binder then holds the effect and main yarns in place. To avoid the possibility of the drafted staple strand unraveling before it is wrapped by the binder, the spindle usually creates a false twist in the staple strand. The staple strand therefore does not pass directly through the hollow spindle but is first wrapped around a twist regulator, which is usually placed under the spindle.

A very wide range of fancy effects can be produced with the hollow-spindle system. Many of these effects can be controlled by controlling the speed of the associated feeding devices. It is possible to make fancy yarns using hollow-spindle systems that include yarns in their effect. Many other effects can be created by controlling the final yarn delivery speed. Since the effect fibers do not have a real twist, hollow-spindle yarns differ from ring yarns in both their appearance and their performance characteristics. The former tend to be larger and have less wear resistance.

Hollow-Spindle Spinning In this process, a yarn twist is replaced by wrapping a filament binder around the main fiber materials used (Figure 1). This results in an impressed yarn structure where most of the main fibers/yarns run parallel to each other along the strand axis, while the filament binder provides the necessary cohesion. Despite the striking similarities, yarns made using the hollow-spindle system are quite different from those made by the conventional ring-spinning system. They may also differ in details of appearance and behavior during processing. Hollow-spindle yarns are mainly used in woven garments or fabrics, although plain yarns have found many other applications such as carpets and medical textiles. When used in the production of fancy yarns, the hollow-spindle technique incorporates the binder and produces an immediate effect rather than using a separate second operation. In yarns produced on hollow spindles, the fancy yarn has no twist to hold the core fibers/yarns together, so there is no cohesion beyond that provided by the binder. When the binder breaks down, the core fibers separate more freely and dramatically in the case of fancy yarns produced by ring-spinning systems. Figure 8.23 shows the schematic of the hollow-spindle system. In this particular example, there are four independent feeding devices, three for the effect fibers and one for the main yarn. The effect fiber is fed in the form of main rovings or slivers. The fibers are then formed using a roller drafting system such as a ring frame. The effect fibers meet the main yarn and then pass through the rotating hollow spindle. A bobbin carrying the binder, usually a filament yarn, is mounted on the hollow spindle and rotates with it. The binder yarn is drawn from the top onto the hollow spindle. The rotation of the hollow spindle wraps the binder around the main strand and main yarn. The binder then holds the effect and main yarns in place. To avoid the possibility of the drafted staple strand unraveling before it is wrapped by the binder, the spindle usually creates a false twist in the staple strand. The staple strand therefore does not pass directly through the hollow spindle but is first wrapped around a twist regulator, which is usually placed under the spindle. A very wide range of fancy effects can be produced with the hollow-spindle system. Many of these effects can be controlled by controlling the speed of the associated feeding devices. It is possible to make fancy yarns using hollow-spindle systems that include yarns in their effect. Many other effects can be created by controlling the final yarn delivery speed. Since the effect fibers do not have a real twist, hollow-spindle yarns differ from ring yarns in both their appearance and their performance characteristics. The former tend to be larger and have less wear resistance. Fig 1 : Schematic diagram of hollow-spindle spinning method

Fig 1 : Schematic diagram of hollow-spindle spinning method

Hollow-Spindle Spinning Process of Yarn Manufacturing