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weaving,the art of forming a fabric by interlacing at right angles two or more sets of yarn or other material. It is one of the most ancient fundamental arts, as indicated by archaeological evidence. Discoveries in the early 1990s in the Czech Republic point to a possible origin in the Paleolithic periodPaleolithic period
or Old Stone Age,
the earliest period of human development and the longest phase of mankind's history. It is approximately coextensive with the Pleistocene geologic epoch, beginning about 2 million years ago and ending in various places between
..... Click the link for more information. some 27,000 years ago. Moreover, the earliest literatures often mention the products of the loom. In primitive cultures weaving was practiced mainly by women.
Although weaving sprang up independently in different parts of the world and was early known in Europe, its high development there in the Middle Ages was brought about by Eastern influences operating through Muslim and Byzantine channels of culture. Byzantium became a center of silk weaving in the 6th cent. In the 9th cent. Greece, Italy, and Spain became proficient. In Flanders a high degree of skill was attained by the 10th cent., especially in the weaving of wool. Flemish weavers brought to England by William the Conqueror and later by Queen Elizabeth I gave a great impetus to the craft there, and Lancashire became an important center. Tapestrytapestry,
hand-woven fabric of plain weave made without shuttle or drawboy, the design of weft threads being threaded into the warp with fingers or a bobbin. The name has been extended to cover a variety of heavy materials, such as imitation tapestries woven on Jacquard looms,
..... Click the link for more information. weaving was brought to a high art in France. In colonial America weaving was a household industry allied with agriculture.
The 18th-century weaving and spinning inventions marked the transition from the old era of domestic craftsmanship to the tremendous, organized industry of today. The factory system of machine weaving produces quantities of standardized material for mass consumption; the result is a loss of the distinctive elements of quality and design. Some of the finest silks, velvets, table linens, and carpets are still woven on handlooms.
The Weaving Process
The first step in weaving is to stretch the warp, or longitudinal, yarns, which must be very strong. The weft, woof, or filling crosses the warp, binding the warp threads at either side to form the selvage. The three essential steps after the warp is stretched are: shedding, or raising every alternate warp yarn or set of yarns to receive the weft; picking, or inserting the weft; and battening, or pressing home the weft to make the fabric compact. In most primitive weaving these operations were performed by the hands alone, as in making rush mats and baskets. Gradually frames for holding the warp evenly stretched and devices for throwing the weft came into use (see loomloom,
frame or machine used for weaving; there is evidence that the loom has been in use since 4400 B.C.
Modern looms are of two types, those with a shuttle (the part that carries the weft through the shed) and those without; the latter draw the weft from a stationary
..... Click the link for more information. ).
Types of Woven Fabrics
Woven fabrics are classified as to weave or structure according to the manner in which warp and weft cross each other. The three fundamental weaves, of which others are variations, are the plain, twill, and satin. In plain weave, also known as calico, tabby, taffeta, or homespun weaves, the weft passes over alternate warp threads, requiring two harnesses only. The relatively simple construction suits it to cheap fabrics, heavy yarns, and printed designs. Variations are produced by the use of groups of yarns, as in basket weave and monk's cloth, or by alternating fine and coarse yarns to make ribbed and corded fabrics, as the warp-ribbed Bedford cord, piqué, and dimity and the weft-ribbed poplin, rep, and grosgrain. The second primary weave, twill, shows a diagonal design made by causing weft threads to interlace two to four warp threads, moving a step to right or left on each pick and capable of variations, such as herringbone and corkscrew designs. Noted for their firm, close weave, twill fabrics include gabardine, serge, drill, and denim. Satin weave has floating or overshot warp threads on the surface which reflect light, giving a characteristic luster. When the uncrossed threads are in the weft, the weave is called sateen.
Pile fabrics have an additional set of yarns drawn over wires to form loops, and may be cut or uncut. Warp-pile fabrics include terry and plush; weft-pile, velveteen and corduroy. In double-cloth weave two cloths are woven at once, each with its warp and filling threads, and combined by interlacing some yarns or by adding a fifth set. The cloth may be made for extra warmth or strength, to permit use of a cheaper back, or to produce a different pattern or weave on each surface, e.g., steamer rugs, heavy overcoating, and machine belting. Velvet is commonly woven as a double cloth. In swivel weaving, extra shuttles with a circular motion insert filling yarns to form simple decorations, such as the dots on swiss muslin. Figure weaves are made by causing warp and weft to intersect in varied groups. Simple geometric designs may be woven on machine looms by using a cam or a dobby attachment to operate the harnesses. For curves and large figures each heddle must be separately governed. The Jacquard loom attachment permits machine weaving of the most complicated designs.
See M. E. Pritchard, A Short Dictionary of Weaving (1956); A. Albers, On Weaving (1965); R. Brown, The Weaving, Spinning, and Dyeing Book (1978).
(looming), the production processes necessary for manufacturing unfinished woven fabrics. Weaving may be classified according to the type of raw material (fiber or yarn) being processed—cotton, wool, silk, linen, or other type.
History. Weaving, like spinning, arose in the Neolithic period and was widely practiced in primitive society. The vertical hand loom appeared in the sixth or fifth millennium B.C. F. Engels considered the invention of the loom one of the most important achievements in the first stage of man’s development (K. Marx and F. Engels, Soch., 2nd ed., vol. 21, p. 161). In feudal times the design of the loom was improved, and devices for preparing the yarn for weaving were developed. The first attempts at mechanizing the weaving process date from the 16th—18th centuries. The most important of them was the invention of the fly shuttle by J. Kay in 1733. In Great Britain at the end of the 18th century, E. Cartwright invented the mechanized loom, and various improvements were subsequently made in its design, primarily in Great Britain. These included the cloth beam mechanism (R. Miller, 1796), the heddle lifter (G. Todd, 1803), and the mechanism for coordinating the movements of the warp and cloth beams (R. Roberts, 1822). The automatic temple, a device for stretching the fabric along the edge, was invented in the USA in 1833.
Russian inventors also made substantial contributions to improved loom design. In 1844, D. S. Lepeshkin patented a stopmotion device that automatically stopped the.loom when the weft yarn broke, and in 1853 S. Petrov introduced the most advanced system for beating in the warp and passing the shuttle. Looms with automatic shuttle changing were developed at the end of the 19th and beginning of the 20th century. The most successful solution to the problem of automatically changing the weft spool in the shuttle was offered by J. Northrop of Great Britain (1890). However, shuttle looms still had substantial drawbacks, such as the small size of the weft package, the uncontrolled flight of the shuttle across the shed at high accelerations, and the laying of just one pick of weft at a time.
Several designs for shuttleless looms appeared at the beginning of the 20th century. They made provision for the weft yarn to be unwound from large, fixed packages and laid in the shed by special mechanisms. Looms of this type were developed in Germany by Gabler in 1926 and by the Soviet engineer V. E. Leont’ev in 1936. In 1927, S. A. Dynnik (USSR) proposed a design for a circular loom with multiple sheds; V. A. Prozorov (USSR) developed a flat loom with multiple sheds in 1939.
Techniques. As a production process in the manufacture of fabrics, weaving consists of preparatory operations, the weaving proper, and concluding operations.
Preparatory operations include winding the warp and weft yarns, warping, sizing, drawing-in, and tying off the yarn ends. These operations are designed to create packages of warp and weft yarns suitable for work on the loom. The warp yarns are usually wound from cops onto conical, cross-wound bobbins or, less often, onto spools suitable for the next operation—warping. The winding is done on automatic winders and similar machines. If the yarn packages are already suitable for warping, the winding process is omitted. In warping, up to 1,000 yarns are wound from bobbins or spools onto the section beam; the process is carried out on warping machines. The application of size, an adhesive colloid in solution, increases the yarns’ durability and resistance to abrasion and repeated stretching during weaving. The drawing-in of the warp yarns through the drop wires is essential if the loom is to stop automatically in the event the yarn breaks. The yarns are drawn through the heddle eyes to form the shed—the space through which the shuttle passes—and to produce the desired pattern for the weave. The yarns are then drawn through the reed splits; the reed beats the weft yarns in to provide the required warp density.
The weft is wound onto spools for shuttle looms by automatic weft winders. For shuttleless looms, the bobbin on the winder is used, or the yarn may be unwound directly from the spinning frame. The weft yarn is often wetted (emulsified or steamed) to ensure that only one loop of yarn at a time unwinds from the package.
The warp and weft are delivered from the preparatory shop to the weaving shop for the manufacture of the fabric. In weaving, the warp yarns are more exposed to the working parts of the loom than are the weft yarns, which places increased demands for strength, durability, and wearability on the warp. The warp is usually manufactured from better raw material than the weft; it has a higher twist and is also strengthened by sizing. A break in the yarn, particularly the warp, is the principal cause of the stopping of a loom; it also lowers the quality of the fabric and creates yarn waste.
The concluding operations of weaving include measuring the length of the fabric on measuring machines, cleaning and shearing, quality control on inspecting machines, and packing on folding machines. All concluding operations are carried out on production lines, on which the loom-state fabric moves as a continuous cloth sewn together from individual pieces of fabric. Flaws in the raw fabric are judged by points, the number of which determines the grade of the fabric.
In Soviet practice, the weaving shop or shops, the preparatory shop, and the inspecting department are all considered production units in the weaving process. This aggregate may operate independently as a mill, or it may be part of a textile combine that includes spinning, twisting, weaving, and finishing operations. The optimum capacity of weaving mills depends on the type of product; for example, there are usually 2,000–4,000 shuttle looms or up to 2,000 shuttleless looms in a mill producing cotton cloth, up to 3,000 pneumatic looms in a mill manufacturing silk fabrics, and up to 800 shuttleless looms in a mill producing worsted fabrics.
Future improvements in weaving will include the mechanization of labor-intensive operations and the automation of production processes. The introduction of shuttleless looms and looms with multiple sheds will make it possible to develop and introduce new forms of labor organization, and processes and machines will be integrated to reduce the number of transfer operations in the preparation of yarn.
REFERENCESTseitlin, E. A. Ocherki istorii tekstil’noi tekhniki. Moscow-Leningrad, 1940.
Rybakov, B. A. Remeslo drevnei Rusi. [Moscow] 1948.
Kanarskii, N. Ia., B. E. Efros, and V. I. Budnikov. Russkie liudi v razvitii tekstil’noi nauki. Moscow, 1950.
Tekhnologiia tkachestva, vols. 1–2. Moscow, 1966–67.
Gordeev, V. A., G. I. Arefev, and P. V. Volkov. Tkachestvo, 3rd ed. Moscow, 1970.
Proektirovanie tkatskikh fabrik. Moscow, 1971.
I. G. IOFFE and V. N. POLETAEV