Investigation into Navel Selection for Rotor Spinning Machine Using Cotton Waste

Abstract

mill that no other spinning system exists enabling this economical application. As a rule, raw material should be selected in such a way as to build a balance between raw material cost and desired yarn characteristics. To obtain a good spinning stability, the yarn must have sufficient twist at the peeling point where it leaves the rotor groove. The necessary twist is created by the help of the navel. The location of this specific part in the yarn withdrawal passage of the spinbox is shown in Figure 1. The yarn drawn from the rotor groove takes a 90° turn inside the navel. The rotation of the yarn around the inner wall of the navel creates an additional false twist on the yarn between the rotor groove and the yarn draw-off tube. This action, which is shown schematically in Figure 2, ensures a high twist moment, enabling the propagation of twist in the rotor groove and an increase in yarn tenacity.