spinning(redirected from spin casting)
Also found in: Dictionary, Thesaurus, Medical, Financial, Wikipedia.
spinning,the drawing out, twisting, and winding of fibers into a continuous thread or yarn. From antiquity until the Industrial Revolution, spinning was a household industry. The roughly carded fiber was at first held in one hand and drawn out and twisted by the other hand. The earliest tools were the distaff, a stick on which the fiber was wrapped, and the spindle, a shorter, tapering stick notched at one end and weighted by the wharve or whorl (a disk of stone or clay). The spindle was twirled to twist the thread, which was then wound on it. With these simple tools were spun extremely fine yarns. In India the delicate threads for the famed Dacca muslin were produced by revolving needle-thin pieces of bamboo in a coconut shell. The primitive Gurkha wheel was used to spin coarse yarns. In Europe from the 14th to the 16th cent. the distaff and spindle were gradually superseded by the spinning wheel. It consisted of a spindle set in a frame and revolved by a driving belt passing over a wheel. The great, or wool, wheel, revolving the spindle directly, then by a pulley, twisted the thread; it was then stopped and revolved in the opposite direction to back off the spun yarn, which was then wound on the spindle. The flax, or Saxony, wheel—a more elaborate mechanism operated by a treadle—drew, twisted, and wound the yarn with a continuous motion suited to flax, wool, or cotton. In England improvements of the loom in the 18th cent., increasing the demand for yarn, stimulated inventions that revolutionized spinning. John Wyatt suggested the use of rollers to attenuate the yarn, a process patented in 1738 by his partner, Lewis Paul. James Hargreaves invented c.1765 the spinning jenny, a frame capable of spinning from 8 to 11 threads at once. The softly twisted yarns were not suitable for use as warp threads, but in 1769, Richard Arkwright brought out his frame, which by means of successive pairs of rollers, each revolving faster than the preceding pair, attenuated the yarn and twisted and wound it on bobbins in a continuous action. Operated at first by horse or mule power, later by water power, and still later by steam, spinning rapidly became a factory enterprise. In 1779, Samuel Crompton, combining the best features of the jenny and of Arkwright's frame, invented the mule spinning frame, forerunner of the modern self-acting mule. Because of its intermittent action, the mule is used for fine or delicate yarns. For the mass production of coarser yarns, the ring frame, an elaboration of Arkwright's machine, invented by John Thorp c.1828, draws, twists, and winds the thread in one rapid, continuous operation.
the technological processes necessary for producing from relatively short fibers continuous yarn used in the manufacture of such textile products as woven fabrics, knitwear, curtains, nets, twine, thread, and rope.
Various types of fiber can be spun. Hence, there is cotton spinning, wool spinning, flax spinning, and so on. In preparation for spinning, the fiber is opened and cleaned (scutched). The fibers are then formed into a sliver, from which the roving is produced after drawing out (drafting) and twisting. Yarn is produced from the roving or sliver by drafting or separation, followed by doubling and twisting.
Hand spinning has been known since the Late Neolithic. It was practiced among almost all peoples, with the exception of the peoples of the Far North, where fur garments were worn. The oldest spinning materials were wool, flax, hemp, and—in some regions—nettle fibers. Cotton was used in ancient India. The earliest spinning method consisted of using the fingers to form small slivers and the palms to twist the slivers in an upright position or on the knees.
The first spinning implements were hand combs and hand spindles (for twisting). The fibers were fastened to a distaff having a bench or were spun directly from the comb. Distaffs and small spindle weights dating from the second millennium B.C. have been excavated in the USSR. Of major importance in the development of hand spinning was the invention of a distaff with a spindle driven by a rotating wheel. Also significant was the invention of a spinning wheel having a spindle with a flyer, which made it possible to twist and wind the yarn simultaneously. Treadle-driven spinning wheels appeared in Europe in the 15th century.
Machine, or frame, spinning appeared in the mid-18th century. In 1738 a continuous-action spinning machine with a drafting device was patented in Great Britain by L. Paul. The machine was capable of drawing out, twisting, and winding yarn. A carding machine was built in 1748. In 1765, J. Hargreaves designed a self-acting spinning frame (spinning jenny) on which sections of yarn of a specified length were produced and then wound. Hargreaves’ machine was improved between 1772 and 1779 by C. Wood and S. Crompton and became known as the mule or spinning mule. An automatic intermittent-action spinning machine was designed in the period 1823–30, and a continuous-action ring spinning frame was produced in 1870. The combing machine was invented by J. Heilmann of France in 1845.
In Russia, R. Glinkov organized a flax-spinning mill in Serpeisk in 1760. He installed machine-driven multispindled spinning frames and combing machines of his own design. In 1799 a cotton-spinning mill (Aleksandrov Manufactory) went into operation near St. Petersburg. Two-zone high drafting systems with a strengthener were put into production at the mill in 1833.
By the middle of the 20th century continuous-action ring spinning frames had replaced the less productive and more complex intermittent-action machines (mules). High-draft and superhigh-draft spinning systems had also been developed. New types of opening-scutching units and combing machines were put into use, and ring-spinning and roving spindles had been perfected.
Three basic stages are distingushed in spinning: (1) preparation of the fibers and the formation of slivers, (2) preparatory spinning, that is, the production of roving, and (3) spinning, that is, the formation of yarn. In some cases, the first two stages are combined, or the second stage is eliminated, with the yarn being produced directly from the sliver.
The preparation of fiber for spinning begins with the opening of the compressed raw fiber by means of needles, pins, teeth, or other working components of the feeders, looseners, openers, and other machines. Impurities are removed from the fibers by scutching machines; the fibers may also be cleaned by aerodynamic and electropneumatic methods. Opening and cleaning usually are done together. Scutching is the basic process in the preparation of wool and flax fibers; the fibrous mass is opened and cleaned simultaneously.
Fibers are blended together to produce a uniform result, that is, to give the fabric uniform properties. Organized blending methods (floor blending, sandwich blending, streamlined blending) or random blending methods (arrangement of the fibers as a result of agitation) are used. Fibers are blended in special blending machines; random blending is sometimes done in opening machines as an accompanying process.
Opening, scutching, and blending machines are often combined, forming, for example, an opening-scutching unit in cotton spinning. In flax and wool spinning the three machines are part of an assembly line.
After cleaning and blending, the fiber is carded to separate the fibers and to remove fine and cohesive impurities and defects. There are two basic carding methods: carding proper, by which the fibers are subjected to the action of the needles or teeth of the working members of a flat or roller card, and combing, which is done on a combing machine.
Carding produces a thin layer of slightly straightened and somewhat parallel fibers; the same carding machine converts the fibers into slivers. Longer fibers that are straighter and more parallel are obtained after combing.
Fiber preparation is completed on a drawing frame, which attenuates the sliver to a certain thickness and then doubles it. During the drawing-out process, which is usually carried out on a mechanical drafting device, the sliver is thinned as a result of fiber displacement, and the fibers are straightened, separated, and made parallel. In the doubling process, separate sections of the slivers are folded together in many different combinations, which determine the uniformity of the yarn. The drawing-out and doubling processes are repeated two or three times in order to straighten and blend the fibers properly. Uniform sliver thickness is maintained most effectively by means of an automatic regulator, which changes the size of the draft in relation to the thickness of the sliver fed into the drafting device.
Spinning directly from sliver on ring frames never became popular, since the necessary drafting devices are so complex. Therefore, roving was produced from sliver in the preparatory spinning stage. A roving frame is used to draw out and twist or double the sliver and to wind the roving onto a bobbin. Twisting, which imparts the necessary strength to the roving, is accomplished by a flyer spindle. The twist is represented by the formula T = ns/vr where T = twist, ns = spindle rotation speed, and vr = the delivery speed of roving from the drafting device. In wool production, the process of doubling is done on roving frames.
In the last stage of spinning the roving is drawn out in the drafting device to the desired fineness and is twisted into yarn, which is formed into packages or cops. The twisting and winding of yarn are performed by a mechanism consisting of a spindle, a ring, and a traveler.
Particularly promising are spindleless spinning methods, which increase production twofold or threefold. The twisting and winding processes are done by independent working members. Several types of spindleless spinning methods are distinguished: pneumatic, vortical, and electromechanical.
In pneumatic spinning the separated fibers are fed by a jet of air into a rapidly rotating chamber, where they are centrifuged against the collecting surface of the chamber. A small sliver is formed and wound onto a bobbin. The yarn is twisted by the rotation of the chamber.
Spindleless self-twisting spinning is used in the production of worsted yarn. To form self-twisted yarn, the roving or sliver is drawn out in a drafting device, and reverse twisting of the small slivers is performed by a twisting mechanism. Self-twisting occurs when two slivers having periodically changing twists are united. The final step involves winding the yarn.
There are several spinning methods, which differ from each other mainly in the type of carding procedure used. The selection of a particular method is determined by the type of fiber being processed and the desired properties of the spun yarn.
Card spinning is used in the production of carded yarn of medium or high linear density from uniform medium-length fibers (medium-fiber cotton, chemical fibers, short-fiber flax, and tow).
Card and comb spinning is used in the production of combed yarn of low or medium density from long, relatively uniform fibers and blends (long-fiber cotton, wool of uniform length, flax tow, chemical fibers, silk wastes). The combing system is used without carding to produce yarn of low and medium linear density from the longest uniform fibers (long-fiber flax, hemp, silk wastes, very long wool).
Condenser spinning, which is characterized by the use of two or three passes of the roller carding machines and by the absence of drawing and roving frames, is used for producing yarn of high linear density from different types of short, uneven fibers and their blends (short wool and wool of irregular lengths, short-fiber cotton, chemical fibers). Such yarn is more loosely and less evenly spun than carded yarn.
The staple spinning is used for the production of yarn from the tow of chemical filaments. Opening, scutching, and carding processes are not used. Sliver is produced on staplers from fibers formed during the cutting or breaking of the filaments. In direct spinning, the yarn is formed on a spinning frame, on which stapling, drawing out of the sliver, twisting, and winding also take place. In another method stapling is performed on a roving frame, and the yarn is produced from roving on a ring spinning frame.
Textured yarns, with high elasticity, are produced by the carding or combing system from blends of chemical fibers having different shrinkage properties. Mélange yarn is made from a mixture of differently colored fibers. Twisted yarns are produced on spinning-and-twisting frames or on twisting frames.
The operating conditions of spinning machines depend on the properties of the fiber, the purpose of the yarn, and the performance characteristics of the machine. It is also regulated by a spinning plan incorporating the desired characteristics of the yarn, such as linear density, twist, draft, and ply.
Future developments in spinning are associated with the creation of high-performance machines, frames, and production lines; utilization of optimum package capacity; automation of package removal and shipping; centralized control of machine operation and product quality; and the adoption of automated systems for controlling production processes.
REFERENCESVasil’ev, N. A. Voprosy teorii priadeniia. Moscow-Leningrad, 1932.
Kanarskii, N. la., B. E. Efros, and V. I. Budnikov. Russkie liudi v razvitii tekstil’noi nauki. Moscow, 1950.
Zotikov, V. E., I. V. Budnikov, and P. P. Trykov. Osnovy priadeniia voloknistykh malerialov. Moscow, 1959.
Mekhanicheskaia tekhnologiia voloknistykh malerialov. Moscow, 1969.
Raschet i konstruirovanie mashin priadil’nogo proizvodstva. Moscow, 1969.
Sevost’ianov, A. G., and N. I. Shilova. Bezveretennoe priadenie. Moscow, 1969.
A. G. SEVOSTIANOV
What does it mean when you dream about spinning?
Spinning in a dream can be represented by spinning of thread on a spinning wheel to create fabric, or a child spinning a top, or even themselves, in circles. It may be that the dreamer is about to embark on some sort of industrious task. It also suggests conjuring up a story or tale.
A production technique for shaping and finishing metal. In the spinning of metal, a sheet is rotated and worked by a round-ended tool. The sheet is formed over a mandrel. Spinning may serve to smooth wrinkles in drawn parts, provide a fine finish, or complete a forming operation as in curling an edge of a deep-drawn part. Spun products range from precision reflectors and nose cones to kitchen utensils.
The fabrication of yarn (thread) from either discontinuous natural fibers or bulk synthetic polymeric material. In a textile context the term spinning is applied to two different processes leading to the yarns used to make threads, cords, ropes, or woven or knitted textile products.
Natural fibers, such as wool, cotton, or linen, are generally found as short, entangled filaments. Their conversion into yarn is referred to as spinning. After a carding operation on the raw material to disentangle the short filaments, the filaments are drawn (drafted) to promote alignment in an overlapping pattern and then twisted to form, by mechanical interlocking of the discontinuous filaments, a resistant continuous yarn.
The term spinning is also used for the production of monofilaments from synthetic polymers—for example, polyamides or nylons, polyesters, and acrylics—or modified natural polymers, such as cellulose-rayon. Generally the monofilaments are stretched (drawn) to increase their strength by promoting molecular orientation and are wound as yarn which can be used directly for threads, cords, or ropes. Such yarn, however, is often cut into relatively short lengths (staple) and reformed by a process similar to that used for natural fibers into a yarn more suitable, in terms of appearance and feel, for making certain textile products. See Textile