摘要 |
A method for drawing and heat-treating an undrawn polyester yarn by drawing the polyester yarn between a heated feed roller and at least one heated draw roller, wherein the surface temperature of the last draw roller is progressively raised from its yarn in-coming side to its yarn out-going side, the yarn is shrunken both on the last draw roller and between the last draw roller and the take-up roller, and the yarn is cooled on the take-up roller. Further, after the method has resumed after being stopped, the running speed of the yarn on the take-up roller is maintained at not more than (100-5.7xS)m/min., wherein S is the total shrinkage of the yarn until the yarn heated during the stoppage has been allowed to shrink in the subsequent step. The yarn is then passed over the take-up roller at a running speed of 200 to 1200 m/min. An apparatus for performing the above method, characterized by the provision of a shrinking part in the last draw roller, means for heating the surface temperature of the last draw roller progressively from its yarn in-coming side to its yarn out-going side and a groove on a separator roller associated to the penultimate draw roller for regulating the yarn path of the last turn of the yarn.
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