Yarn Strength

The " breaking strain " or strength of both cloth and yarn is often of great importance. Nearly all government contracts contain a breaking strain clause. Numerous machines are obtainable to accurately determine the resistance to breaking of fabric or yam (see Yarn Strength)

A fancy yarn made with a centre yarn of possibly cheap material around which is wound a more expensive material which completely covers the cheap yarn. Sometimes a core is introduced for additional strength. The " Urgoite " core yarn consists of a core of paper wrapped with wool,)ute, flax, etc. The " Leclercq Dupire " yarn has a cotton core and a worsted covering. Tinsel yams are also core yarns.

A single yarn made as a cheap imitation of a two-fold yarn by being subjected to two separate twistings. The term really signifies double twisting. The yam is spun on the mule with soft twist and, weft way, then gassed and again twisted at the ring doubler weft way. Thus the twist at the ring doubler is added to the twist at the mule. It is a super quality yarn and spun free from knots and other faults, superior to the ordinary single-twist, but not equal to two-fold. It is of greater strength than ordinary yarn.

A term used in the lace industry to denote cotton yarn, wound on to the thin brass bobbin for use as weft; in all counts ranging from 2/20's to 2/300's, the bulk ranges from 2/60's to 2/100's. They are also termed C.B. yarn (this is the doubter's name for curtain bobbin). The yarns are strong, compact and regular. They are wet doubled to give the maximum strength.

A mixture yarn composed of a thread of cotton and a thread of wool doubled together. The cotton thread is just strong enough to give sufficient strength and elasticity to the shoddy woollen yarn and enable it to bear the strain in the knitting process for which it is used.

Specially hard-twisted yams, containing from 30 to 70 turns per inch and produced in singles and doubled. The usual range is 40's to 100's single, 2/80's to 2/200's doubled. The yarns are used for voiles, crepe-de-Chines and fabrics where the aim is to produce crinkles through the strong tendency of the yarns to contract in length. In cotton, yams are made up to six- or nine-fold for special purposes. Crepe yarns are also produced in wool, silk and rayon. An official definition states: Silk, rayon, cotton or wool threads may be given a twist of a specific number of turns per inch. The thread contracts in the twisting, and the evenness of the twist, the type of twist, and the number of turns determines to a definite degree the character of the face of the texture for which the twisted yarn is used. The twist in the yam is set by a process of steaming. The twist co-incidently increases the strength of a thread to a limited extent. The twist may have a bearing upon the lustre of woven or knitted fabrics and upon the capacity of dye penetration and absorption. A crepe yarn may consist of a single thread twisted one way, or of several threads joined by throwing into one thread by a combination of twists.

Paper is wound in roll form and then cut into narrow flat strips from ¹/₄-in. upward. After damping, the edges of the strips are turned and then twisted into round thread form. Paper yarn is used for weft in fabrics such as canvas, mats, packsheets, for the backs of rugs and carpets, and is also made into fancy articles. If required in colours it is dyed in the pulp form. The paper stripes may be twisted around a core of fibre to give strength.

Yarns for making motor tyres. Cord tyre yarns are made 15-fold 23's generally by doubler winding five ends together at the first doubling and three of these five-folds at the finisher doubling. Every precaution is taken to keep the tension uniform and impart maximum strength to the yarn.

Another term for doubled yarns. Yarns may be folded to increase strength, to produce special twist effects or to produce grandrelle effects.

Coarse yarns spun from the waste of the spinner and used as warp for cheap cotton suitings, towels, sheetings, sponge cloth, etc. Its chief characteristic is strength, so it is generally used for warp yarns. The method of spinning diners from that for condenser yarns. As with the condenser system there are two kinds of preparation spinning. The hard waste section includes cop waste, reelers', winders', doublers', ring waste, etc. The soft waste section produces yarns from comber waste, strips, blowings, fly, droppings, etc. The machinery used in the average hard waste mill comprises cop bottom breakers, scutchers, breaker cards, Derby doublers, finisher cards, roving frames, mule or ring frames. The manipulation of the material is the same as for condenser spinning up to and including the Derby doubler. The laps from the Derby doubler are fed to the finisher card in the usual way. As the web reaches the doffer it is divided into four, five, or sometimes six slivers. Each sliver is then drawn through a " trumpet" by rollers, and thence through a coiler into a can (see waste)

Безразлично, что использовать-- When dealing with twistless yarns, there is no choice between using the fabric strength and the yarn strength in the free state.

See Yarn Strength and Cloth Strength.

Silk yarns are composed of a number of silk filaments twisted together, usually 8 to 12 to form a thread. The filaments have a natural coating of gum which gives strength and elasticity, but reduces lustre. The gum must be boiled off if lustre is wanted, which may be done either in the yarn state or when woven in cloth. Silk yarns are divided into two classes, " thrown silk" and " spun silk," the first being yarns that are made by the processes of reeling and throwing, and the second consisting of yarns spun from waste silk. Thrown Silk, or Net Silk comprises organzine and tram yarns, organzine being made from the most perfect cocoons and used for warps. Tram is made from the inferior cocoons and used as weft. All silk contains a proportion of natural gum, and the amount of gum removed give rise to the following terms: - Boiled-off Silk - Yarn which has had all the gum removed, and has the highest sheen (see Boiled-off). Hard Silk - Yarn that has not undergone any boiling-off process. Ecru Silk - Yarn boiled to remove about 3 per cent to 5 per cent of the gum by light washing in lukewarm water. Souple Silk - Yarn boiled to remove about one-sixth of the gum. Bengal Silk - See Bengal Silk. Berlin Silk - A silk yarn made for fancy hand work. It is produced by doubling from 4 to 8 twisted singles grege by a right-hand twist; then again doubling three of these with a left-hand twist. The thread is very round, smooth, and hard, also known as cordon-net. Blond Silk - A special silk yarn made by doubling three grege threads left-hand twist, then doubling three of these together with right-hand twist. Brights - Silk which has been entirely de-gummed in the skein and then dyed. Bourette, Bourrette Yarn - A low grade of silk yarn made from the waste produced by schappe spinning. Canton Silk - See Canton Silk. Chiffon Twist - Single raw silk threads, 50 or more turns per inch. Used for chiffons, crepe-de-chines, etc. Crepe-de-Chine - Hard twist tram silk, about 40 to 70 turns per inch. Made from 3 to 5 raw silk ends. Usually woven as weft. Crepe Georgette - Hard twist raw silk usually made from two threads 13/15 deniers, 50 or more turns, both right and left twist, used for crepe georgettes as warp and weft. Crepe Twist - This is tram silk hard twisted, having from 30 to 100 turns per inch. Used for making fabrics of a crepe character both all silk and mixtures. Cordonnet Silk - See Berlin Silk; also under Cordonnet. Eri Silk - A raw silk obtained from the wild silkworm " Attacus ricini." Flock Silk - A general term used to indicate silk yarns made from the outer uneven parts of the cocoon. Floss Silk - Used principally for embroidery purposes. It is a thrown silk and made by doubling two thick raw singles with right-hand twist together with a left-hand twist. Galette Silk - A coarse silk yarn made from waste. Grenadine Silk - Organzine silk with a large number of turns per inch. Jaspe Silk - Silk warps printed in the hank. Ombre Silk - Skein dyed yarn in a gradation of shades, which run in sequence of depth of colour, varying from five up to forty shades. Schappe Silk - A spun silk yarn which is made from silk degummed by the maceration process used on the Continent (see Schappe Silk). Soie Ondee - See Soie Ondee. Silk Yarns - In addition to the foregoing yarns see under the following terms for further silk yarns: - Cable, Cevennes, Chappe, Chine, Clochepeid, Crocheting, Crue (see Ecru), Cuite Cusier, Cusirino, Degummed, Docken, Doup-pion. Ecru, Embroidery, Etschingo, Filature, Filature a 1'Europeune, Filet, Florette, Fringe, Goffered, Grege, Gum Hainin, Hard, Kahing, Knitting, Lousy, Marabout, Maybasch, Melange, Mele, Mi-cuit, Minchcw, Nett, Noil, Organzine, Ouvrees, Oval, Pearlina, Pel, Pelo, Poie, Pure dye Silk, Raw (see Grege), Re-reels, Retorse, Senegal, Sewing, Simonita, Soft Singles, Soie Ondee, Souple, Spun, Steeped, Strafilato, Stumba, Thrown, Tors San File, Tram, Tramette, Tsatlees, Tussah, Twist, Washed, Zaguri.

Cotton yarn or fabric to which lustre is imparted by treating it under tension with caustic soda. This mercerised cotton yarn has a greater affinity for dyes than unmercerised. Most mercerised yarns are two or more fold and the singles are specially spun and gassed prior to doubling. Mercerised yarns are spun with less twist than ordinary yarn in order to increase the lustre of the yarn. The cotton used is usually good Egyptian. The mercerising process increases the strength of the yarn by about 30 per cent, and decreases the weight about 5 per cent.

(See knitting). All yarns used for knitting are termed hosiery yarns in Leicester, but in America only yarns actually used for knitted footwear come under this term. These yarns are much softer than required for weaving. Miscellaneous Yarns - Goat wools, such as llama and alpaca are employed in spinning. yarns for the knitting trade. Vicuna and camel yarns are used to a limited extent. Ramie yarn is specially employed for knitting gas mantle fabrics. Soft spun flax yams have been used for making underwear fabric. Chenille and other manufactured threads are used to a small extent in warp knitting. Composite yarns, such as union yarns - spun from a mixture of wool and cotton fibres; cordon yarns - cotton and worsted singles, doubled together; wool and rayon or spun silk, cotton and rayon or spun silk are largely used to produce self or two-colour effects. Fancy yarns, such as slub yams, voiles, and curled and loop yarns are also employed. Hosiery Yarns (Cotton) include condenser, hosiery, condenser lisle thread, mercerised and sewing cottons. Condenser yarns are spun in coarse counts from low-grade cotton, Indian and American. They are carded, condensed and mule spun, and possess little twist. Hosiery cotton yarns vary considerably in counts and qualities, practically all varieties of Indian, American and Egyptian being used in varying proportions to obtain suitable mixture for quality and price. Cheaper yarns are carded and mule spun. American and Egyptian cotton yarns are combed mainly with the object of removing seed particles. High-class Egyptian and Sea Islands cotton yarns are super-combed. The chief features of a hosiery cotton yam should be: (1) Regularity; (2) cleanliness; (3) fullness. Regularity prevents the making of cloudy fabric, showing thick and thin places. Cleanliness is essential, as the seed particles clog the eyelet hole in the yam guides and cause breakages. Fullness is desirable to cover the loop interstices. Elasticity and pliability are quite as essential as tensile strength. Yams are usually soft spun and if two-fold soft doubled, average twists in two-fold being 2/10's 6¹/₂T., 2/20's 8¹/₂T., 2/30's 10T., 2/40's 16T., 2/80's 20T. Softer twist less 25 to 30 per cent of average (T= turns per inch). Lisle thread is a comparatively hard-twisted and doubly-gassed thread in which there are no projecting fibres. It is always of a two-fold character, and the doubling twist varies from 24 to 34 turns per inch in 2/60's. It is used largely in the manufacture of ladies' hose tops and feet and for lace hosiery. Mercerised yams are used largely in the fancy trade, a comparatively soft twist again being employed. Sewing cottons for seaming, linking and making-up are specially prepared in two to six cord open and reverse twist. Woollen and Worsted Yarns include lamb's wool, wheeling, skein yarns, gala yams (woollens), worsted, crossbreds, fingering, cashmere, dry spun botany (see under each name). Worsted and crossbred yarns of various qualities are used. These yams are spun softly with " hosiery twist." The drawing may be open, cone or French, and the spinning may take place on cap, ring or flyer frames. The chief essentials of hosiery yarn are softness of fibre, fullness, minimum of twist consistent with the requisite tensile strength, regularity, pliability and elasticity. Cashmere Yarns, as used in the knitted goods industry, are spun from short, loose and weak wools as well as from better qualities by French drawing and mule spinning. A small proportion of real cashmere is used for outer garments. In recent years nylon yarns have been largely employed.

1. high-strength chemical yarn