Unfinished worstedis a fabric woven with yarn with very little twist in it, and finished so as to make it appear covered with loose fibers, concealing the twill effect. After leaving the loom the cloth is placed in a fulling machine which condenses the fibers, thus increasing the density. It is then passed over hot presses after a slight shearing.
Finished Worstedis woven with yarn with a considerable twist, and finished in such a way as to show the construction of the cloth clearly. The finishing consists simply of scouring the cloth and not fulling it and then passing it through hot water baths between heavy rolls to remove all the soap. It is then sheared and pressed.
Zephyr.Light worsted yarn, also light weight cotton gingham. Zephyr is Greek for the light west wind.
Zibeline.A cloth manufactured with Merino lamb’s wool for warp, and a light wool mixed with camel’s hair for filling; or, worsted warp and camel’s hair for filling; or either of the foregoing warps and a mixture of wool, camel’s hair, and fine cashmere for filling. The long cashmere hair spreads over the surface. Used for ladies’ tailor-made coats or suits, according to weight. The name is derived from the Latin wordsabellum, meaning sable, and was applied originally to a variety of long-haired fur generally thought to be the same as sable. Zibeline has long hairs on its right side, some grades being almost like fur.
FOOTNOTE:[15]Suggestions To Teachers. In connection with the study of fabrics the author has found it advisable to have the pupils insert in a blank book a sample of the fabric they are studying. In this way the pupil can examine both the filling (weft) and warp threads.
[15]Suggestions To Teachers. In connection with the study of fabrics the author has found it advisable to have the pupils insert in a blank book a sample of the fabric they are studying. In this way the pupil can examine both the filling (weft) and warp threads.
[15]Suggestions To Teachers. In connection with the study of fabrics the author has found it advisable to have the pupils insert in a blank book a sample of the fabric they are studying. In this way the pupil can examine both the filling (weft) and warp threads.
Cotton.Cotton is the most important vegetable fiber used in spinning. The cotton fiber is a soft, downy substance which grows around the cotton seed. When examined under the microscope it appears as a long twisted cell. Owing to the fact that the cotton-plant yields so readily to the varying conditions of soil and climate, there is a large variety of cottons, each having some peculiarity which is considered enough to place it in a distinct class. An idea of the number of species of the cotton-plant can be obtained from the fact that the United States Department of Agriculture has recorded about one hundred and thirty varieties. The most important varieties are:Gossypium herbaceum,G. arboreum,G. hirsutum,G. barbadense, andG. peruvianum. The botanical name of a plant is divided into two parts: first the family name, followed by the species name.
TheGossypium herbaceumgrows from four to six feet in height and bears a yellow flower. The seeds are covered with a short gray down. The fiber it bears is classed as short. It is found in Egypt, Asia Minor, Arabia, India, and China. The short-stapled variety of Egyptian cotton is from this species.
TheG. arboreumwhen full grown attains a height from fifteen to twenty feet. The seed is covered with a greenish fur and is enveloped in a fine, silky down, yellowish white in color. It is found in Egypt, Arabia, and China.
TheG. hirsutumis a shrubby plant, its maximum height being about six feet. The young pods are hairy, and the seeds are numerous and covered with a firmly adhering green down. It is probable that this is the original of the green-seeded cotton which is now cultivated so extensively in the Southern States of America, and which forms the bulk of the supply from that source.
TheG. peruvianumis similar to theG. barbadense. The Brazilian and Peru cottons are from this species.
TheG. barbadensegrows from six to fifteen feet high; its flowers are yellow and its seeds black and smooth, being quite destitute of the hair that distinguishes other members of the species. It is a native of Barbadoes or has been cultivated there for a long time. Cottons of the finest texture belong to this species—Sea Island and Florida cottons—from which our finest yarns are spun, and it is used chiefly in the manufacture of fine lace. The long-stapled Egyptian and several other varieties are said to be from this stock.
Cotton Growing Countries.The most suitable situation for growing cotton is between 35 degrees north and 40 degrees south of the equator. The chief cotton growing countries of the world in order of importance are: United States, India, Egypt, and Brazil. Cottonis also grown in the following countries, but in no quantity or quality comparable with the four named above—West Indies, west coast of Africa, Asia Minor, China, and Queensland.
The best soil for growing cotton is a light loam or sandy soil, which receives and retains the heat, and at the same time preserves a good supply of moisture. Cold, damp days are not suitable for its growth, while deep rich soils develop too much leaf and stalk. The best climate for the cultivation of cotton is where frost and snow are of short duration, dews are heavy, and the sun bright, warm, and regular. New soils generally produce the best cotton. The character of the cotton fiber is dependent upon three things, the species of the plant, the nature of the soil, and the locality in which it is grown.
Rough Peruvian.The nature of this cotton is harsh and wiry and resembles wool so nearly that it is almost exclusively used to mix with woolen fabrics. The staple is rough and generally strong, and is of a springy tendency,i.e., it does not lie close like American.
East Indian.India depends upon the monsoon for its moisture, and the success or failure of the crop is decided by that phenomenon of nature. Indian cottons as a rule are coarser and shorter than American cottons. The land is prepared before the breaking of the monsoon, and the planting begins after it. There is not the same care bestowed upon the cultivation of the Indian cotton, nor are such improved methods practised as in America. The ancient routine of past generationsstill persists, and as a consequence the yield per acre is less than one-half that of America. Moreover the acreage planted is only about two-thirds that of America. The better growths of East Indian cotton were once largely used in this country for filling, owing to their good color and cleanliness; but of late years the consumption has steadily decreased, owing chiefly to the increased takings by the Indian mills, also to the exports to China and Japan, and to the preference shown by English spinners for American cotton.
Egyptian Cotton.Egyptian cotton, on account of its long staple and silky gloss, is imported in considerable quantities. Egyptian is largely used in the manufacture of hosiery, and also for mixing with worsted yarn. Owing to its gloss it is used for mixing with silk, and on account of its strength it is made into the finer sewing threads. Egyptian cotton is sometimes so charged with grease that it has a greasy smell; and to make it workable it is necessary to sprinkle it with whitening. It has been observed that velvets woven (or piled) with Egyptian filling do not finish as well as when picked with yarns made from American cotton, the reason for this being that the greasy nature of the Egyptian cotton fiber often varies in strength, causing different shades in the finished goods. This greasy nature is said to be due to two things: (1) the fertility of the soil; (2) the extent to which the cell walls of the fibers are developed.
In addition to cotton, other crops are grown in Egypt—rice, sugar, beans, barley, onions, etc.—and theacreage devoted to cotton is regulated to some extent by the prospects as to which crops are likely to pay best. It is calculated that not more than one-third of the area is usually devoted to cotton.
Sea Island Cotton.This is the finest growth of cotton, and it commands the highest price. The staple, which is long and silky, varies in length from one and a half to two and a half inches. It is used for making fine muslins, laces, spool cotton, and other fabrics, and is also largely mixed with silk. It is said that this cotton was first introduced into America in 1786 from the Bahama Islands, whither it had been brought from the West Indies. It was first cultivated in Georgia, where it was found that the small islands running along the coast were best adapted for its growth, hence the name “Sea Island.” It was also grown on the uplands of Georgia, but although remaining good, the quality deteriorated. Counts as high as four hundred are occasionally spun in Sea Island cotton.
Other Varieties.Cotton grown in the Southern States under widely varying conditions of the soil, climate, and care in cultivation, naturally varies in length, strength, and other qualities of staple. Cotton known as “Uplands” or “Boweds” varies in length from three-fourths to one and one-sixteenth inches and is used for filling; this is grown in North and South Carolina, Georgia, Florida, Alabama, and Tennessee. Cotton used for twist is grown in Texas, Louisiana, Mississippi, and Arkansas, and the length of the staple varies from one to one and three-sixteenths inches. Inthe swampy and bottom lands in some of the states (notably Alabama, Louisiana, Mississippi, and Arkansas), cotton is grown with staple ranging from one and one-eighth to one and one-fourth inches. In addition to these, there are especially long stapled growths, known as “Extras,” “Allen Seed,” and “Peelers,” which measure one and three-eighths to one and five-eighths inches. Of late there has been an extensive demand for long-stapled American cotton (one and three-sixteenths to one and one-half inches), owing to the development of fine spinning.
Cotton Raising.Cotton is planted with a machine, which puts it under the ground about one and one-half to two inches. It is not planted as corn is, that is, dropped so far apart, but is planted in a continuous stream. After the cotton comes up out of the ground, when it is about three inches high, it is hoed by ordinary labor with a hoe, and is cut out or, rather, thinned. This is called “chopping out” and is for the purpose of removing the inferior or weak plants until only one strong plant is left. The distance between the plants depends on the nature of the plant, frequently about twelve inches being left between them.
The American Crop.The first step taken is the preparation of the ground for planting. This begins in the southern part of Texas as early as the middle of January, in Florida about the third week; in Alabama, Georgia, Mississippi, and Louisiana, about the beginning of February; in Arkansas, Tennessee, and South Carolina from about the middle of February to thebeginning of March. Actual planting begins according to latitude, principally from the middle of March to the middle of April, and ends in the first half of May. These dates, however, are dependent upon the state of the weather. When the weather is unusually wet the start is late. The plant suffers from the rank growth of grass and weeds, and extra labor is required to keep the fields clean. In abnormally hot weather, especially after rains, the plant sheds its leaves, thus exposing the bolls, which fall off, whereupon replanting becomes necessary. In addition to injuries by the weather the cotton-plant is subject to depredations by insects. Of late years the greatest pest has been the Mexican boll weevil.
The cotton-plant blooms ten or eleven weeks after planting. An early bloom is taken as a sign of good crops. When the crop is an early one, picking may commence in the districts in which it ripens first in the latter half of July; but the usual date is the beginning of August, following on in the various districts in succession until the early part of September. The plant goes on fruiting as long as the weather is mild and open. It finishes in the early regions about the beginning of December, the others following through December and closing in the later regions about the middle of January. Frosts play an important part in the ultimate yield. An early killing frost over the entire belt would curtail the size of the crop by 500,000 bales in a season, as was the case in 1909 when about 32,000,000 acres were planted. Light frosts and late frosts do little harm to the cotton-plant; in fact it is contended that the latefrosts do much good under certain conditions of the crop, by opening the bolls that otherwise would not open, and thus adding to the quantity of the late pickings. The effect of frost upon the lint so picked is to produce tinged and stained cotton. Early killing frosts occur in some seasons in the early part of November, when much of the yield may be curtailed. When killing frosts occur late in the season, when the fruiting is practically over, it has little or no effect upon the yield except as regards the color.
The ripening of the crop proceeds in three stages, the bolls nearest the ground maturing first, then those around the middle of the plant, and lastly the top crop. Pods half ripe are often forced open and the fiber sent on with good cotton. East Indian is more highly charged with unripe cotton than American. The work of picking is not heavy, but becomes tedious from its sameness. Each hand as he goes to the field is supplied with a large basket and a bag. The basket is left at the head of the cotton row, the bag being suspended from the picker’s shoulder by a strap, and used to hold the cotton as it is plucked from the boll. When the bag is full it is emptied into the basket, and this routine continued throughout the day. Each hand picks from 140 to 180 pounds of cotton per day. The average yield in the South varies from 500 to 600 pounds per acre. Every boll of cotton contains seeds resembling unground coffee; when these have been removed by the gin, there remains about one-third the weight of the boll in clean cotton.
PICKING COTTON
Ginning.The next operation to which cotton is subjected is that of ginning, or separating the seeds from the fiber. This work was formerly accomplished by hand, and so great was the quantity of seeds that frequently an entire day was occupied by a workman in separating them from one pound of cotton. At the present day the devices for separating the lint from the seed are of two classes: roller gins and saw gins. The former device is the more ancient, having been used from the earliest times by the Hindoos. In its simplest form it consists of two rollers made of metal or hard wood, fixed in rude frames, through which the cotton is drawn and the seeds forced out in the process. An improved form of the roller gin is at present used for cleaning the long-staple Sea Island cotton. The saw gin, which works on an entirely different principle, is the machine which, with its improvements and modifications, has separated the seed from fiber almost exclusively for one hundred years of American cotton growing. In this machine the seed cotton is fed into a box, one side of which is formed of a grating of metal strips set close together, leaving a narrow opening from one-eighth to a quarter of an inch wide. Into these openings a row or “gang” of thin circular saws project mounted upon a revolving mandrel. The long, protruding teeth of the saws, whirling rapidly, catch the fibers, and pull them away from the seeds. The latter, being too large to pass through the openings of the grating, roll downward and out of the machine. The lint, removed from the row of saws by a revolvingbrush, passes between rollers and is delivered from the machine in the form of a lap or bat.
This machine is responsible for much of the “nep” (or knots) found in American cotton, which is caused when the machine is overcharged. The Whitney gin will turn through more cotton than any other type of machine, and will clean from 200 to 300 pounds per hour. When the machine is running at high speed the tendency is to string and knot the cotton.
COTTON GINThe upper figure shows Whitney’s invention. The lower figure shows a later form.
The working of the ordinary gin is as follows: The wagon loaded with cotton is driven under a galvanized spout called the sucker, through which there is a suction of air which draws the cotton into the gins. In each of the gins there are seventy circular saws revolving on one shaft. These saws are about one inch apart, and the teeth go through the gin breast, much as if one were to put the teeth of one comb into the teeth of another comb. This process takes the lint cotton off the seed, and by the use of brushes the cotton goes into the lint flute, into the condenser, and into the box, where it is revolved and made into a bale. While the lint is going through this process, the seeds, being heavier andsmaller, draw to the bottom of the gins, fall into an auger which is operated by a belt, and then are dropped into a conveyor and carried to the seed pile or houses. The lint goes in one direction and the seed in another.
When the seed is taken from the cotton at the gin, it is covered with a lint of cotton. In order to remove this the seeds are put through a delinter, which takes off the small, short fiber from the seeds, leaving them clean. This seed is then put through a huller which takes off the outside hull or thick skin. The kernel is then put through a hydraulic press, which squeezes the cotton-seed oil from it and leaves the “meal.” Cotton-seed oil is used for many purposes, such as making olive oil, butter or oleomargarine, lard, etc. Of late an experiment has been made with the meal for use in the place of flour, and has been pronounced a success. Seed crushing has now become an important industry, with the cotton crop each year amounting to between 12,000,000 and 13,000,000 bales of 450 pounds each.
The Cotton Gin.The cotton gin was invented in 1792 by Eli Whitney, a citizen of Georgia, but a native of Massachusetts. The importance of this invention to the cotton industry of the world cannot be overestimated. It was the one thing needed to insure a sufficient supply of raw material to meet the requirements of newly invented machinery for spinning and weaving. The result of Whitney’s invention was the rapid extension of the culture of cotton in the UnitedStates, and its permanent establishment as one of the leading staples of the country.
Cotton Bales.After the cotton is ginned and baled it is shipped to the mill. The standard size of a cotton bale in the United States is 54 × 27 × 27 inches, and contains nearly 500 pounds. To produce this bale over 1,600 pounds of seed cotton are required. The bales are wrapped in jute bagging and strapped with sheet-iron bands, this covering adding about twenty-five pounds to the weight of the bale.
The Bessonette cylindrical bale is turned out by a self-feeding press, which receives the lap of lint from the gin between two heavy rollers. The fiber is rolled upon a long wooden spool so tightly as to press out nearly all the air, and forms a package of uniform shape and size throughout, having a diameter of fourteen to sixteen inches. The bales are covered with cotton cloth, held in place by small wire hoops. It is claimed that the cotton is rolled so tightly by this process that the bales are practically fireproof and waterproof.
Egyptian bales are compressed into a shape similar to the American bale, but the average weight is over 700 pounds.
The Indian bales, which are more closely compressed than the American, usually weigh 400 pounds.
Cotton is purchased by the mill authorities in the shape of a bale. The method is to purchase from cotton brokers, samples being furnished to the buyer from which to make selection.
STOREHOUSES
The commercial value of cotton is determined by its length, fineness, strength, pliability, smoothness, regularity, color, and cleanliness. As a rule, the cotton that is the longest is also the finest, but by no means the strongest. Thus, Sea Island cotton has the longest staple with the least diameter, and Hinganghat (an Indian cotton) is much inferior to it in both respects. The strength of the latter, however, is 50 per cent greater than the strength of Sea Island cotton. In every other respect Sea Island cotton is in advance over Hinganghat cotton. It is the most valuable, especially for the production of fine yarns.
The most regular cotton is Orleans, in which the length of the staple varies only a small fraction of an inch. In consequence of this there is less loss in working Orleans than is the case with the other cottons, owing to the fact that their fibers vary in length.
The Leading Growths of Cotton.In order to purchase the raw material of the cotton manufacture, to arrange the “mixing” or have much to do with the raw material in any other capacity, one should know as much as possible of its characteristics; for ignorance may cause much trouble and no little loss to those who have to spin the cotton. Each crop differs from the previous one to a greater or less degree, as it depends entirely upon the weather. Thus, in a very dry season there is a “droughty crop” which, while it may be (and generally is) clean and well up in class, will be weak, short, and of irregular fiber. In order to obtain the desired length and strength of staple the buyer willhave to pay a relatively higher price than in what may be termed a normal season.
FANCY COTTON LOOM
Again, in a crop that is poor in class, a defect that may have been caused by too much rain in the early or middle stages of its growth, or by unfavorable weather for the production of cotton of good grade, the staple will probably be all that could be desired, leafy and small, but the buyer will have to pay more to obtain his usual grade, especially if he requires it for goodfilling. Then there are seasons when the crop turns out fairly well in class and staple, but the cotton is wasty, dirty, or abnormally leafy; and in this case the buyer has to exercise great care and judgment in calculating the extra loss that will ensue.
The terms of purchase of cotton include an allowance of 4 per cent for tares. That is, a bale of cotton weighing 400 pounds would be paid for as 384 pounds, or should the buyer have reason to believe that the tares are unusually heavy, he has the option of claiming the actual tare. This is ascertained by stripping ten bales and weighing the covering and the hoops, which means considerable work, and although it is at the option of the buyer, it is an exception rather than the rule.
As a result of these causes we find cotton divided into the following grades:
Full Grades of Cotton.Egyptian cotton is graded as follows: extra fine, fine, good, fully good fair, good fair, fair, middling fair, middling.
Indian cotton is graded as follows: superfine, fine, fully good, good, fully good fair, good fair, fully fair.
Brazilian cotton may be classed: fine, good, good fair, fair, middling fair, middling.
American cotton has seven grades: fair, middling fair, good middling, middling, low middling, good ordinary, and ordinary.
In addition to the full grades there are half and quarter grades. The American cottons are graded as follows:
The following are a few of the leading varieties of cotton, with the numbers of yarn they will make:
During the last few years considerable discussion has taken place among mill men, both in this country and abroad, bearing upon the subject of moisture contained in baled cotton. Of course the natural moisture in the cotton fiber varies, as might be expected, from year to year, according to the character of the season during the picking. The standard of moisture is based upon what is known as regain, that is, if 100 parts of absolutely dry cotton are exposed to the air, they willabsorb about 8½ per cent of moisture, although a much higher per cent is sometimes found.
In some of the small Southern mills located in the cotton raising section, the cotton is delivered by team direct from the gin, without going through the compress. In this way they save the greater part of transportation expense. They also save in the strength of the cotton fiber itself, since the process of compression injures the fiber. They get better cotton, being nearer the source of supply and having better opportunities for selection.
When the cotton arrives in the shape of a bale, it is necessary to cut ties and loosen up the cotton before use. This may be done in two ways. One method being to pull the bale apart by hand, and the other to pass it through a bale breaker or similar machine, which loosens up the cotton by means of beaters. It now starts on a continuous journey through successive machines until it is made into yarn. The yarn is made into a warp, and the warp interlaced with the filling yarn to make cloth, and the cloth finished for the market.
Not every country is adapted for making cotton yarn, for certain conditions are necessary to manufacture good yarn. If the atmosphere is too warm or too dry, the fibers will become brittle and will not twist well; if too wet they collapse and stick. Lancashire County, England, seems to have been fitted by nature for cotton spinning. It has just the right climate, a moist temperature, and copious water supply. There are hills on the east of the valley, forming a water shed, and thetown lies in a basin covered with a bed of stiff clay, that holds the water, allowing it to evaporate just fast enough to keep the air in the moist condition needed to fit the fibers for weaving. Countries that have not these conditions are obliged to produce them by artificial means—humidifying, etc.
PICKER ROOM1. Hopper where the cotton from the bale is fed into Picker.2. “Lap” showing how the cotton is prepared for the card.3. Picker Machine (complete).
1. Hopper where the cotton from the bale is fed into Picker.2. “Lap” showing how the cotton is prepared for the card.3. Picker Machine (complete).
PICKER ROOM—SHOWING END VIEW OF PICKER1. Lap of Cotton.
1. Lap of Cotton.
Picker Room.The first step in the conversion of the bale of cotton into yarn consists in giving the cotton fibers a thorough cleaning. This is accomplished by feeding the cotton to a series of picker machines called in order, bale breaker, cotton opener and automatic feeder, breaker picker, intermediate picker, andfinisher picker. These machines pull to shreds the matted locks and wads of cotton (as we find them in the bale), beat out the dirt, stones, and seeds, and finally leave the cotton in the form of batting upon the cylinders; this batting passes from one machine to another until it issues from the finisher picker as a downy roll or lap.
(Sometimes the bale breaker is not used in the mill.)
CARD ROOM1. Roving Can—receptacle to hold the sliver. After it is filled it is transferred to either ribbon lap machine or drawing frame.2. Cylinder of the card. The cotton is on this cylinder in the form of a web.
1. Roving Can—receptacle to hold the sliver. After it is filled it is transferred to either ribbon lap machine or drawing frame.2. Cylinder of the card. The cotton is on this cylinder in the form of a web.
Carding Machine.When the lap of cotton leaves the picker it goes to the carding machine, where it is combed into parallel fibers by means of a revolving cylinder covered with wire teeth called card clothing.As the cotton is fed to the card in the form of a sheet or lap from the picker, it is supposed to have been freed from a considerable quantity of sand, seed, etc., but there still remain nep, fine leaf, and short fibers, which are removed during carding.
On leaving the card cylinder the lap has become a gossamer-like web thirty-nine inches broad. This web next passes through small “eyes,” which condense it into a narrow band about an inch in width, known as card sliver.
When a lap is delivered from the finisher picker, it should weigh a given number of ounces per yard. The method of ascertaining the weight is to make each lap a standard number of yards in length and weigh each lap. The machine can be regulated so as to give the desired weight per yard.
Combing.When an extremely fine and strong yarn is required, in addition to carding, the fibers are also subjected to the process of “combing.” This may be said to be merely a continuation of the carding process to a more perfect degree. The chief object is to extract all fibers below a certain required length, and cast them aside as “waste.” This is done in order to secure the very best fibers calculated to give the strongest and best results in the spun yarn.
The process of combing follows carding. The card delivers the cotton in the form of a sliver or strand, while the combing machine requires the fibers to be delivered to it in the form of sheets, nine to twelve inches wide. This is done by taking a number of cardslivers and forming a lap of them by passing the sliver through a sliver lap machine. The laps are passed through the comber. This machine consists essentially of a series of rollers, nippers, and rows of metal teeth. By the action of these, the short fibers are separated and combed out, and the long ones arranged in parallel order in the form of a thin, silky strand, in which condition it is sent to the drawing frames to be drawn out. Of course it must be understood that a combing machine is used by only a small percentage of cotton spinners. For ordinary purposes a sufficiently good quality can be made without a comber. As there is from 15 to 35 per cent waste to this operation it may be readily seen that it is costly, and limited entirely to the production of the very best and finest yarns, such as those intended for sewing or machine thread, fine hosiery, lace curtains, underwear, imitation silks, and fine grades of white goods. There are combing machines that comb short staple cotton.
Drawing.The cans containing the slivers are taken from the card or combing machine (as the case may be) to the drawing frame. The object of this machine is mainly to equalize the slivers, combining a number of them together so as to distribute the fibers uniformly. The condition of the fibers on leaving the card or comb is such that a slight pull will lay them perfectly straight or parallel, and this pull is given by the drawing frame rollers. Of course the fibers coming from the comb are parallel, but it is necessary to alternate them by the drawing. The drawing frame is a machine consistingof a number of sets of rollers, the front roller having a greater speed than the rear ones.
COTTON COMB ROOM1. The cotton in the form of a “lap” ready to pass through the comb.
1. The cotton in the form of a “lap” ready to pass through the comb.
The slivers, which are as nearly as possible the same weight per yard, are combined together in the drawing and emerge from the pair of front rollers as one sliver weighing the same number of grains per yard as a single sliver fed up at the back. This process is repeated two or three times, according to requirements, the material then being referred to as having passed through so many “heads” of drawing. It is not unusual to pass Indian and American cotton through three deliveries.
The object of all the processes thus far described has been that of cleaning (in the picker), arranging the fibers in a parallel position to each other, making uniform, and drawing out the stock. In every case the stock delivered from a machine is lighter than when fed into it, and contains just twist enough to hold it together and prevent its being stretched or strained when unwound from the bobbin, and fed into the next machine. The minimum amount of twist in roving is desirable for the reason that it permits the stock to be drawn out more easily and uniformly, the little twist that is put in the roving by the slubber being practically eliminated when it is passed through the rolls of the intermediate. The same applies in the case of the roving passing from the roving to the spinning frame.
Fly Frames.The process in the manufacture of yarn after the cotton has passed through the drawing frame consists of further attenuation of the sliver, but as the cotton sliver has been drawn out as much as ispossible without breakage, a small amount of “twist” is introduced to allow of the continued drawing out of the sliver.
From the drawing frame, the drawing passes through two, three, or four fly frames, according to the number of yarn to be made. All these machines are identical in principle and construction, and differ only in the size of some of the working parts. They are the slubber, intermediate, roving,—and fine or jack frame-fine, and the function of each is to draw and twist.
ROVING DEPARTMENT1. Slubber machine, showing sliver of cotton passing through the rolls and then given a twist while it is wound on the bobbin.
1. Slubber machine, showing sliver of cotton passing through the rolls and then given a twist while it is wound on the bobbin.
Intermediate Frame.The function of the intermediate frame is to receive the slightly twisted rove from the slubber and add thereto a little more twistand draft. The rove is taken from two bobbins to one spindle in the machine, an arrangement which tends to insure strength and uniformity. The principle of the machine is in other respects the same as that of the slubbing frame.
Roving Frame.The function of the roving frame is to receive the twisted rove from the intermediate and add more twist and draft, thereby further attenuating the rove. As in the intermediate frame the rove is generally taken from two bobbins for one spindle.
Fine or Jack Frame.This machine is used when fine yarns have to be made. It is built on the same principle as the preceding frames, the only difference being that a finer rove is made from which finer numbers of yarn can be spun. As in the slubber, intermediate, and roving frames, the rove is taken from two bobbins for one spindle.
Spinning.In the manufacture of single ply yarn the final process is that of spinning, which consists in drawing out the cotton roving to the required size, and giving it the proper amount of twist necessary to make the yarn of the required strength. While the spinning frame is built on entirely different principles from the roving, intermediate, or slubber frame, the object of each machine is the same as that of the spinning frame. The principal point of difference is the amount of twist imparted to the cotton roving.
ROVING ROOM1. A drawing frame showing the sliver of cotton passing through the machine.2. A slubber showing the sliver passing through and wound on bobbins.3. Roving machine showing the cotton passing from one bobbin through the roller to another.
1. A drawing frame showing the sliver of cotton passing through the machine.2. A slubber showing the sliver passing through and wound on bobbins.3. Roving machine showing the cotton passing from one bobbin through the roller to another.
The objects of the spinning process are:
1. Completion of the drawing out of the cotton roving to the required size.
2. Insertion of the proper amount of twist to give the thread produced strength.
Excessive speed causes defects in the yarn and undue wear and tear on the machine.
There are two methods of spinning: ring spinning and mule spinning. The mule spinning is the older form. There are but few mule frames in operation in this country.
Mule Spinning.The function of mule spinning is to spin on the bare spindle, or upon the short paper tubes, when such are required to form a base for the cop bottom. The mule will spin any counts of yarn required, and is especially adapted for yarn in which elasticity and “cover” are essentials. Hosiery yarns are produced on the ordinary cotton mule and are very soft spun.
The bobbins of roving are placed in a creel at the back of the machine, the stands of roving being passed through the rolls and drawn out in the same manner as at the roving frame. The spindles are mounted on a carriage which moves backward and forward in its relation to the rolls, the distance roved being about five feet. When the spindles are moving away from the frame the stock is being delivered by the rolls, the speed at which the spindles move away from the rolls being just enough to keep the ends at a slight tension. The twist is put in the yarn at the same time.
SPINNING ROOM. COTTON DEPARTMENT1. Humidifier—an apparatus to give off moisture.2. Spinning frames—showing the cotton as it comes from the roving frame and passes through the spinning frame.
1. Humidifier—an apparatus to give off moisture.2. Spinning frames—showing the cotton as it comes from the roving frame and passes through the spinning frame.
When the spindles reach their greatest distance from the rolls, the latter are automatically stopped and the direction of the motion of the spindle carriage reversed. The yarn is wound on the spindle while thecarriage is being moved back toward the rolls, the motion of the rolls being stopped in the meanwhile, the spindles revolving only fast enough to wind up the thread that has been spun during the outward move of the carriage.
The mule is a much more complicated machine than the ring frame, its floor space is much greater, and more skilled help is required for its operation. Under ordinary conditions it is not practical to spin finer yarn than No. 60s on a ring, while as high as No. 500s is said to have been spun on a mule. The same number of yarn can be spun on a mule with less twist than on the ring. This is important in hosiery yarn.
Ring spinning is used for coarse numbers, and has greater production and requires less labor than mule spinning. Ring-spinning yarn is used for warp purposes.
Ring Spinning.The function of ring spinning is to draw out the rove and spin it into yarn on a continuous system. The yarn made is spun upon bobbins.
The ring spinning differs from mule spinning in having the carriage replaced by a ring, from which the machine takes its name. The ring is from one and one-half to three inches in diameter, grooved inside and out, and is connected with a flat steel wire shaped like the letter D, called the “traveller.” Its office is to constitute a drag upon the yarn, by means of which the latter is wound upon a bobbin. Its size and weight depend on the counts of yarns to be spun; coarse yarns demand the largest ring and heaviest traveller.