Torque modification of false-twist textured yarn by air twister.

Abstract

There have been a few methods to modify or to reduce the torque of false-twist textured yarn, but they are too complicated in operation or machine set-up and are somewhat imperfect in performance. In this paper a new method is attempted in which an air twister was equipped at the exit of the 2nd heater of a tandem type false-twisting machine to twist a textured yarn again in a direction reverse to the initial twist direction. The effects of various treating conditions including the construction of the air twister on the yarn properties are described. The snarling tendency of the obtained yarn is reduced remarkably by an increase of twist added by the air twister, while the other properties are varied insignificantly. It is possible to choose the proper modifying conditions to attain the non-torque yarn, when the treating conditions in the subsequent processes are given. When an air twister is used in which an air conduit of air flow is inclined at 60 degrees to the yarn passage, it gives results superior to the other conditions except the inferior twisting efficiency.