纺织英语第三版课文翻译LessonTwentyFive-YarnWinding.doc

Lesson Twenty-Five第25课 Yarn Winding ( 1 )络纱 Yarns as manufactured and packaged are not in the optimum condition to be used to form fabrics. After yarn formation, both spun and continuous filament yarns are not immediately usable in fabric forming systems. Package size, build and other factors make it necessary for the yarn to be further processed to prepare it to be handled efficiently during fabric formation.生产并卷装好的纱线并没有处在用于生产织物的最佳状态，纱线形成后，短纤纱和长丝都不能立即用于织物编织系统。卷装的尺寸大小、形状和其他因素让纱线进行进一步加工以便在织造过程中高效传送是有必要的。 For weaving and warp knitting, many yarns are presented simultaneously in the form of a warp sheet. These yarns are taken from packages called beams. Shuttle looms need a ling yarn package, or quill, which fits in the shuttle; while shuttleless looms and weft knitting machines use yarn from large packages called cheeses or cones. 对机织和经编来说，许多纱线以片纱形式同时排列在一起。这些纱线退绕的筒子叫织轴。梭织机需要一个特殊的适合于梭子的纬纱筒子或纬管，而无梭织机和纬编机所用纱线退绕的大筒子叫扁柱形筒子或圆锥形筒子。 From the above it can be seen that the yarn, packaged as it comes from spinning, is virtually use less. It must be repackaged to meet the particular needs and demands of the fabric forming system in which it is to be used. This, in fact, is one of the functions of yarn preparation, to put the yarn on a suitable package for a particular fabric forming system.从上文可知，从细纱机纱下机后卷装成形的纱线几乎是没有用的。它必须重新进行卷绕以满足编织系统的要求。这其实是纱线准备的一个功用，就是使纱线以合适的卷装适应于特殊的编织系统。 The first step in yarn preparation for both knitting and weaving is winding. 对机织和经编来说，纱线准备的第一步是络纱。 The reasons for winding yarn are to produce a package which is suitable for further processing, andto inspect and clear (remove thick and thin spots) the yarn. To perform the above tasks a winder is divided into three principal zones: the unwinding zone, the tension and clearing zone, andthe winding zone. To rewind the yarn on a new package, it must first be removed from the old package. This is accomplished in the unwinding zone. This zone merely consists of a creel, which holds the Old package in an optimum position for unwinding. 络纱是为了形成一个适合于进一步加工的卷装，检查并清除纱线粗节和细节。为完成以上任务，一个络纱机可分为三个主要工作区域：退绕区、张力和清纱区、络纱区。 为将纱线重新卷绕成新的卷装，必须将其从旧的筒子上退绕。这个工序在退绕区完成。这个区只是由一个纱架组成，这个纱架用于支持纱筒并使之处在利于退绕的位置。 In side withdrawal, the spool must rotate in order for the yarn to be removed. The advantage of this system is that the yarn does not rotate upon withdrawal and therefore the yarn twist remains constant. Its disadvantage is that the spool must rotate. At high winding speeds, due to inertia, the rotation of the spool may lead to tension variations in the yarn. Furthermore, provision must be made to stop the spool if, for any reason, the winder stops. If this is not done the rotational momentum of the spool will cause it to remain in motion allowing yarn to be unwound without being taken up. Also, upon start-up, higher tensions are developed because the winder must overcome spool inertia.侧向退绕中，筒子必须转动，以便于纱线退绕。这种退绕方式的优点是，退绕过程中纱线不旋转，所以纱线捻度保持不变。缺点是，筒子必须转动。高速络筒时，由于惯性，筒子的转动会导致纱线上的张力波动。另外，如果因某些原因，络筒机停机时必须有使筒子停止运动的装置。如果没有这样的装置，筒子的转动惯量会使它保持转动，纱线退绕而未被卷绕。而且，一旦启动，因为络筒机要克服转动惯量，会产生更大的张力。 In the over-end withdrawal method, the package need not be rotated as the yarn is pulled over the end of the package. This method is the simplest and most common method of yarn withdrawal. There are, however, two factors which must be taken into account when this method of withdrawal .The first of these factors is known as ballooning. As the yarn is unwound from the package a high speed, centrifugal forces cause it to follow a curved path. As the yarn rotates, it gives the illusion of a balloon above the package. This ballooning leads to uneven tensions being produced in the yarn which may or may not alter some of the particular properties of the yarn. 轴向退绕中，纱线从筒子一端退绕时，筒子不必转动。这种退绕方法最简单也最常用，但当使用这种方法退绕时有两个因素必须考虑。 第一个因素是气圈。当纱线以高速从筒子上退绕下来时，离心力使其按弯曲路径行进。当纱线旋转时，它会在筒子上显示一个圈状影像。气圈导致络纱时的张力不匀，从而可能会改变纱线的特定性能。 The second factor for consideration is that for each time one complete wrap of yarn is removed from tide supply package the twist in that length changes by one turn. For most yams this change is insignificant and may be ignored. However, some fabrics are constructed using flat yarns of metal, polymers or rubber. In these cases the yarn must remain flat and even one turn of twist is unacceptable. These yarns can not be unwound using the over-end method and the side method must be used.第二个要考虑的因素是，每次一根完整的经纱从供纱筒退绕下来时，在这段纱线上捻度会增加或减少一捻。对大多数纱线来说，这种改变不重要，可以忽略。但是一些用金属、聚合物或橡胶的扁平长丝织成的织物，纱线必须保持扁平状即使只有一个捻度变化也不行。这些纱线不能用轴向退绕方法退绕，而只能用侧向退绕法。 The next zone is the tension and clearing zone. It is in this zone that the yarn receives the proper tension to provide an acceptable package density and build for further processing. This zone consists of a tension device, a device to detect thick spots, or slubs, in the yarn and a stop motion which causes the winding to stop in the case of yam break or the depletion of a supply package. The yarn is directed into this zone by a guide.下一个工作区是张力和清纱区。在这个区域中，纱线获得合适张力以保证合适的卷装密度和成形形状，便于进一步加工。这个区组成为：一个张力装置、一个纱线粗细节检测装置和一个断头自停装置，当纱线断头和供纱筒纱线用完时，它使络纱机停机，纱线由导纱器引入该区。 Guides fall into two categories: closed, which require a yarn end to thread, and open, which do not. Open guides, however, give less positive guiding. It is important that guides be kept smooth to prevent damage to the yarn through abrasion, although friction damage can develop in too smooth a guide. Guides are usually made from hard stainless steel or from ceramics.导纱器分为两类：封闭式，需要将纱线穿过，而开放式则不需要。但开放式导纱器是消极式导纱器。对导纱器来说，保持表面光滑以防止对纱线的摩擦损伤，但是无论多么光滑，摩擦损伤都会发生。导纱器通常用不锈钢或陶瓷制成。 Following the guide the yam enters a tension device. The purpose of the tension device is to allow the maintenance of proper tension in the yarn in order to achieve a uniform package density. The tension device also serves as a detector for excessively weak spots in the yam which break under the added tension induced by the tension device.穿过导纱器，纱线进入张力装置。张力装置的目的是使纱线保持合适张力，以保证均匀一致的卷装密度。张力装置也作为一个纱线弱节的检测装置，它增加的张力会使弱节断开。 Tension devices fall into three categories:capstan tensioner , additive tensioner, andcombined tensioner.张力装置分3种：柱式张力器、倍加式张力器和联合式张力器。图4（略）是柱式张力器 The capstan tensioner depends upon the coefficient of friction between the yam and the post, denoted by, and the angle of wrap, denoted by.If the incoming tension is denoted by Tin and the outgoing tension by TOUTT out then, for the capstan tensioner, the relationship between the incoming and outgoing tensions is given by: 柱式张力器取决于纱线和立柱间的摩擦系数，用 表示，经纱角度，用 表示。如果输入张力用T-in表示，输出张力用Tout表示，柱式张力器输入与输出张力可表示为：Tout=T-in 12e（在指数的位置） Where e is approximately 2.718 , the base of the natural logarithms. 这里，e是自然对数的底数，大小约为2.718 The following observations may be made about the capstan tensioner:下面是有关柱式张力器的结果分析：(1) Since, and e are