Task 2 To describe the woolen&worsted spinning process描述毛粗纺和精纺加工过程

General information Wool spinning毛纺

Wool spinning systems are processes that spin wool，and manmade fibers cut to the length of wool，into yarns by either the woolen or the worsted process.Woolen yarns are carded and spun；worsted yarns are carded，combed，drawn，and spun.Wool fibers are sorted and scoured as part of preliminary processing；the other fibers are not.

Sorting and Scouring

Each（previously graded）fleece is opened carefully at the mill，and expert graders pull it apart.The fibers are separated according to spinning qualities：fineness，length，and trash.Extremely long，coarse wools are classified as carpet wool.Fairly long fibers are classified as combing wools and are reserved for sheer wool fabrics and worsteds.Fibers shorter than 5 cm（2.5 in.）are used in woolens.

The sorted wool is scoured with water and detergent or with solvent to remove the natural grease or oil and water-soluble impurities from the fiber.The oil that is removed is recovered and sold as lanolin.The fiber is rinsed thoroughly，then dried and sprayed with a lubricant for ease in processing.

Some wool is carbonized to remove the vegetable matter，such as burrs，twigs，and leaves，trapped in the fleece.The fiber is treated with a dilute sulfuric or hydrochloric acid solution or with salts that become acids when heated.Then the fiber is heated to around 95℃（200℉）to char the vegetable matter without harming the wool.The wool is then passed through a series of rollers that crush the carbonized materials and shake it out of the fiber.

Woolen system

Fibers from several lots are combined and delivered to the wool carding machine.Although the equipment is different，the process is similar to that used for short-staple carding.Wool cards have card cloth with longer wires，and there are usually several carding cylinders operating in tandem.The fibers are pulled onto the card，where the fiber assemblage is opened up and some trash is removed.Short fibers are left in because they are needed to impart some felting qualities to wool fabrics.As the fibers are pulled from the card as roving，or roping，they are somewhat straightened out and made parallel.

The roving（roping）goes directly to the spinning frame，where it is drawn out to the desired diameter，twist is inserted，and the spun yarn is wound onto a spinning bobbin.As with cotton yarns，the yarn is then rewound on packages suitable for knitting or weaving.

Because no separate drafting operation occurs in woolen yarn processing，the yarns have less fiber orientation than carded short-staple yarns produced on cotton-spinning systems.They are characterized by nonuniformity，bulk，and a rough，hairy surface.Woolen system can be summarized as Fig.2.9.

Worsted system

For worsted yarns，the wool fibers are carded just as for woolen yarns.The card sliver is processed through a comber to remove short fibers and any remaining foreign matter and to produce a parallel alignment.The short fibers，which are removed to reduce felting，are called noils.The strand containing the long fibers is referred to as top.Worsted yarns have a relatively smooth，even surface and compact structure.Worsted system can be summarized as Fig.2.10.

Semi-worsted spinning

The designation semi-worsted means that the worsted process is followed with the exception that there is no combing stage.Instead of combed top，the drawframes are fed with card silver.

Semi-worsted are character between woolen and worsted yarns.Usually they are made from course fibers and are quite hairy，but they are also quite regular due to the doubling and drafting.

New Words and Expressions

worsted 精纺

woolen yarns 粗纺毛纱

worsted yarns 精纺毛纱

sort 分级，选毛

scour洗毛，皂洗

preliminary 初加工

grade 分级

fleece 羊毛，套毛

coarse wools 粗羊毛

fairly long 比较长的

sheer wool fabrics 薄型毛织物

worsteds 精纺毛织物

detergent 清洁剂

solvent 助剂

grease 油脂

water-soluble 水溶性

recover 储存起来

lanolin 羊毛脂

rinsed 冲洗

spray 喷洒

lubricant 润滑剂

carbonize 炭化

burr 草刺

twig 小树枝

trap 缠绕

dilute 稀释的，淡的

sulfuric acid 硫酸

hydrochloric acid 盐酸

char 烧焦

harm 损伤

crush 压碎

shake 震动，抖动

lots 批号

short-staple carding 梳棉机

wool cards 梳毛机

card cloth 金属针布

in tandem 一前一后

assemblage 集合体

orientation 取向

nonuniformity 不均匀

bulk 膨松

rough 粗糙

hairy 毛绒

foreign matter 杂质

parallel alignment 平行排列

felting 毡缩

noils 精短毛

top 毛条

Notes

1.The roving（roping）goes directly to the spinning frame，where it is drawn out to the desired diameter，twist is inserted，and the spun yarn is wound onto a spinning bobbin.

（粗纺梳毛机生产的）粗纱直接在纺纱机上纺纱，此过程中，粗纱被牵伸至设计的细度，并被施加上适当的捻度，最后纺成的纱卷绕到纺纱机的筒管上。

2.Because no separate drafting operation occurs in woolen yarn processing，the yarns have less fiber orientation than carded short-staple yarns produced on cotton-spinning systems.

由于粗纺生产不存在独立的牵伸工序，所以粗纺纱的纤维取向度不如棉纺系统生产的短纤维纱。

Exercises

1.What are the basic wool spinning processes?

2.What are the differences between woolen yarns and worsted yarns?