Draw twisting - with drawn yarn connected to undrawn fed through draw twister at start-up

摘要

A length of drawn synthetic yarn is attached to the end of undrawn synthetic yarn (esp. polyester) wound onto a package, and the length of drawn yarn is threaded-up through the draw rollers, heater and false twist bush of a draw twister and fed to a take-up device. The draw-twister is then started up to the take-up drawn yarn so as to commence feed of undrawn yarn from the package through the draw-twister. Thus no undrawn yarn which crystallises and breaks when heated is fed to the heater and yarn breakage during start-up is eliminated. The length of drawn yarn may be formed by drawing a part of the undrawn yarn on the package, or alternatively a length of drawn yarn may be tied to the end of the undrawn yarn on the package. Pref. the heater prior to false twisting is a tube heater, and the yarn may pass through a second tube heater after false twisting.