Principle of Rotor and Friction spinning

Rotor system :

In open-end spinning, the yarn twisting action is separated from the winding action and the package has to be rotated only at a relatively low rotational speed. The process can be divided into the following steps: opening, transport, alignment, overlapping and twist insertion. In the rotor-spinning process, as shown in Figure 1, the individual fibers are carried into the rotor in an air stream and placed in contact with the collecting surface so that a strand of fibers is assembled around the periphery. As the fibers are pulled, the yarn is fed by the rotor to make the yarn. Rotor spinning is best suited for spinning short staple-fiber yarns. Recent developments in electronic control have allowed the development of rotor spinning machinery which is also capable of producing slub yarn. These yarns are used in upholstery and drapery rather than clothing fabrics, although they are sometimes used in denim fabrics. They are made using a combination of simple open-end spinning devices, which usually include an electronically controlled device for short acceleration of the drawing-in roller. Due to the back doubling action inside the rotor, it is not possible to produce slabs shorter than the rotor circumferential length because any change in the fiber feed material is spread over the minimum length of the rotor circumference.

Attempts have been made to vary the fiber flow and thus vary the appearance of the yarn by introducing pressurized air into the fiber-transport tube. However, the effects caused by using this method are very limited, because the fiber flow in the transport tube is small and the yarn variation due to airflow changes is very small.

Rotor system In open-end spinning, the yarn twisting action is separated from the winding action and the package has to be rotated only at a relatively low rotational speed. The process can be divided into the following steps: opening, transport, alignment, overlapping and twist insertion. In the rotor-spinning process, as shown in Figure 1, the individual fibers are carried into the rotor in an air stream and placed in contact with the collecting surface so that a strand of fibers is assembled around the periphery. As the fibers are pulled, the yarn is fed by the rotor to make the yarn. Rotor spinning is best suited for spinning short staple-fiber yarns. Recent developments in electronic control have allowed the development of rotor spinning machinery which is also capable of producing slub yarn. These yarns are used in upholstery and drapery rather than clothing fabrics, although they are sometimes used in denim fabrics. They are made using a combination of simple open-end spinning devices, which usually include an electronically controlled device for short acceleration of the drawing-in roller. Due to the back doubling action inside the rotor, it is not possible to produce slabs shorter than the rotor circumferential length because any change in the fiber feed material is spread over the minimum length of the rotor circumference. Attempts have been made to vary the fiber flow and thus vary the appearance of the yarn by introducing pressurized air into the fiber-transport tube. However, the effects caused by using this method are very limited, because the fiber flow in the transport tube is small and the yarn variation due to airflow changes is very small. Friction system Friction spinning is a different open-end spinning technique compared to rotor spinning. Instead of using a rotor, two friction rollers are used to collect the loose fibers and twist them into yarn. The principle of DREF-2 is shown in Figure 2. The company also manufactures the DREF 3 machine, which has an additional drafting unit in the machine to feed the drafted staple fibers to form the main material. The fibers are fed in sliver form and opened by the opening roller. The open fibers are blown off the opening roller by air flow and carried to the nip area of two perforated friction drums. The fibers are drawn onto the surface of the friction drums by air suction. The two friction drums rotate in the same direction and the fiber strands are twisted due to friction with the two drum surfaces. The yarn is withdrawn parallel to the axis of the friction drum and supplied to a package forming unit. A high twisting speed can be obtained even when using a relatively low speed for the friction drums, because the diameter of the friction drum is much larger than the yarn.

Fig 1 : Schematic diagram on the Principle of rotor spinning

Friction system:

Friction spinning is a different open-end spinning technique compared to rotor spinning. Instead of using a rotor, two friction rollers are used to collect the loose fibers and twist them into yarn. The principle of DREF-2 is shown in Figure 2. The company also manufactures the DREF 3 machine, which has an additional drafting unit in the machine to feed the drafted staple fibers to form the main material. The fibers are fed in sliver form and opened by the opening roller. The open fibers are blown off the opening roller by air flow and carried to the nip area of two perforated friction drums. The fibers are drawn onto the surface of the friction drums by air suction. The two friction drums rotate in the same direction and the fiber strands are twisted due to friction with the two drum surfaces. The yarn is withdrawn parallel to the axis of the friction drum and supplied to a package forming unit. A high twisting speed can be obtained even when using a relatively low speed for the friction drums, because the diameter of the friction drum is much larger than the yarn.