Corded yarn

High tenacity, tire cord yarn viscose 3.7 9.7 27.0... 

Polyesters (Uses fabrics, tire-cord yarns, and yacht sails)... 

Finally, we must introduce the term cord - a constiuction of two or more twisted yam ends (Figure 17.1c). For example, staple fibers are first twisted into a thin yarn and two or three yarn ends are then twisted - in the opposite direction -to form a corded yarn. This is a common construction for textile knitware or fabrics, and carpet yarns. Cords are also used in industrial applications. Filament yarns are then twisted to high levels (several hundred turns per meter) and twisted yarns are combined in a second twisting step - again in the opposite direction - to form twofold or threefold cords. A well-known example is tire cord. 

Subsequent to the twisting, the tire cord yarns are woven. Because normal fabric structures with nearly constant warp and weft density show less-optimal deformation and vulcanization characteristics, a special construction was developed for tire cord fabrics. Tire cords have only up to 10 weft threads made of cotton yarn per 10 cm and therefore have a very open structure. The weft has no carrying function in the tire. It serves only as a supporting thread to facilitate further processing steps. 

Standard Test Methods for Tire Yarns, Cords, and Woven Fabrics. ASTM standard D885M-94 includes test methods for characterizing tire cord twist, break strength, elongation at break, modulus, tenacity, work-to-break, toughness, stiffness, growth, and dip pickup for industrial filament yams made from organic base fibers, cords twisted from such yams, and fabrics woven from these cords that are produced specifically for use in the manufacture of pneumatic tires. These test methods apply to nylon, polyester, rayon, and aramid yams, tire cords, and woven fabrics. 

Static Adhesion Tests for Organic-Based Yarns, Cords, and Fabrics. The most commonly used static adhesion tests are the H-test... 

The economics of recovery are a very strong function of the amount of zinc used in the preparation of the yarn and the ratio of acid to zinc in the spinning bath. In manufacturing industrial yarns and tire cords, it is common to use 4.5 to 7.5 kg of zinc per 100 kg of yam. This high concentration of zinc makes recovery extremely attractive. Textile yams use less zinc, and although recovery is still the most economic solution, it offers less of a return. These two cases are presented as extremes, with many plants falling between the two values. 

We can manufacture fibers from a wide range of polymers. Polyamides, polyesters, and polypropylene can be woven or knitted into fabrics, ranging from those as coarse and strong as those used in back packs, luggage, and sails, to soft and highly flexible fabrics used in sweaters, shirts, and other apparel. Polymer filaments and yarns can be twisted or woven to make string, twine, cords, and ropes. 

Nylons belong to the class of polymers known as engineering polymers that is, they are strong, tough, and heat resistant. We can readily extrude and mold nylons to form a wide variety of useful objects, such as tubing, furniture casters, and automotive air intake ducts. Nylons are commonly spun into filaments or fibers. These can be used directly, or braided, or twisted to form threads, yarns, cords, and ropes, which may be further woven to make fabrics. In their fibrous forms, nylons are used in carpets, backpacks, and hosiery. 

In the manufacture of fast cord the first process is to coat paper or textile yarns with a blackpowder/nitrocellulose dope by a dipping process. These yarns are thoroughly dried and a number of them passed through an extruder and given a thick covering of plastic incendiary composition. The cord thus produced is covered with a protective layer of plastic, usually polyethylene. The overall diameter of the cord is about 2-5 mm. 

The speed of burning of fast igniter cord depends on the speed of burning of the blackpowder-coated yarns and this depends in turn on the gas channels left in the construction of the fuse. The remainder of the fuse is also combustible, so that there is no pressure build up due to lack of venting. Should a minor pin hole or break in the outside layers be produced and water enter, the incendiary composition will continue to burn so that the fuse will not fail, although it will slow down for the distance of the damage. 

Slow igniter cord consists of the same type of plastic incendiary composition extruded not over combustible blackpowder-coated yarns,... 

Fiber products account for about 15% of polypropene consumption. The products range from continuous filaments for carpeting and rope to melt-blown fibers for nonwoven goods. Specific applications include outdoor carpets, yarns for upholstery and automobile seats, and replacements for canvas in luggage and shoes, disposable goods (diapers, surgical gowns), ropes, and cords. 

Forming packages composed of wound strands normally are not supplied to industrial users wilhuul further processing. Strands are twisted and plied before being woven into fabric. A plied yarn, for example, is coated with a latex binder before being used as a tire-cord reinforcemenl. 

Natural materials can be found in many forms in museum collections. The items in this photograph include wool, cotton, wood, leather, dried plant materials, paints, and metal alloys. Rug/carpet kurdish mid-twentieth century wool on cotton, naturalpigments/dye. Basket Hopi piki-bread tray, wicker, early twentieth century. Kachina c. 1970 cottonwood root with water-based (poster) paint, fabric, wool, feathers, yarn, fur ruff, unsigned (cloth "cape is also painted). Books calfskin, marbled paper, gold. Baseball leather, linen cord, pen ink. Glove leather, metal (grommets). Gun wood, metal (brass, steel). 

Van der Meer SJ, Dynamic Mechanical Properties and Permanent Deformation of Yarns, Cords and Fabrics , PhD Thesis, Delft University of Technology, 1970. 

Fig. 12.5. Flow diagram for manufacture of viscose yarn (1) cellulose sheets and caustic soda (2) steeping press (3) shredder (4) xanthating churn (5) dissolver (6) caustic supply (7) ripener (8) filtration (9) deaeration (10) filtration (11) continuous process (12) tire cord (13) pot spinning (14) staple spinning.

Safety fuses are black powder cords with an external yarn winding adjusted to a definite combustion rate - usually 120 s/m. The purpose is to initiate to explosive charge by igniting the blasting cap of the primer. The fuse must be freshly cut in the plane perpendicular to its axis, and the plane of the cut must reach the ignition level of the cap. 

Cord A relatively thick fibrous product made by twisting together two or more plies of yarn. 

Twist in the yarn Most yams have filaments that are twisted. The main reason for this is that an untwisted yam is difficult to weave or knit. Two types of twists can be given to the yam, a counterclockwise twist or S twist and a clockwise twist or a Z twist. Figure 2.1 shows these twists. We can also make a ply yam by using reverse twist directions. This serves to balance out residual stresses. We can also twist together two or more plies to make a cord. Commonly, yam designation on a fiber spool provides information such as name, linear density, number of fibers and fiber type. 

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