< Page:EB1911 - Volume 28.djvu
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815
WOOL, WORSTED AND WOOLLEN MANUFACTURES

French drawing and spinning. to positively control the driving and speed of both flyer and Kobbin in all the drawing frames of such sets as that described above. Such control is usually effected by a pair of cones, from which this system has taken its name. viz. " cone " drawing. In fig. t6 a usual type of cone drawing-box is illustrated. The chief advantages of this system seem to be the possibilities of employing larger bobbins, and thus obtaining greater production, the consumption of relatively less power, and more particularly the production of a softer sliver with less twist, partaking more of the character of a French roving. Spinning is usually effected upon the cap frame (see fig. 17)a frame in which the bobbin, resting upon a fixed spindle, is itself driven at say 5000 revolutions per minute to put in the twist, while the friction of the yarn on the cap which covers the bobbin enables the bobbin to wind up upon itself the yarn as delivered by the front rollers. The weakness and the strength of the cap frame is that to make reasonably hard bobbins the bobbins must be driven at a high speed. The French are noted for a special system of worsted spinning, which, producing soft botany yarns of a marked type, is worthy of more than passing comment. The preparation is very similar to the preparation of botany yarns for the English system save that as a rule the order of the operations are carding, gilling, combing, back-washing and finishing. The characteristic features of the method lie in the subsequent drawing and spinning. The drawing-box as shown in fig. 18 consists of back rollers, porcupine or revolving gill, front rollers, rubbers and winding-up arrangement. Thus there is no twist inserted, the slivers being treated softly and openly right away through the processes. A set of this type usually consists of two gill-boxes preparing for combing, comb, back-washing machine and two finishing gill-boxes, first drawing frame, second drawing frame, the stubbing frame, the roving frame and the elf-acting mule. After leaving the last box as a fine soft pith-like sliver, spinning is effected upon the worsted mule. The main differences between the worsted and the woollen mule are firstly, the worsted mule is fitted with preliminary drafting rollers, and secondly, there is little or no spindle draft. As the mule is an intermittent worker it is natural to contrast it with the cap frame, which

runs continuously. What the real advan-FlG. 17. — Section of Cap tage is it is difficult to say, but the muleSpindle. spun worsted yarn trade is becoming C, Care the front rollers yearly of more importance, and it is of a cap spinning frame de- pleasing to note that English spinners livering the yarn through are at last doing a fair share of this the centring board D under business. theedgeofthecapEto Upon whichever system the yarns have the bobbin F, which rests been spun it will frequently be necessary upon the tube and wharlG, Doubling

  • ° twofold them and some which

in turn rest upon the twisting' times to three- and fourfold lifter-rail I, which eft'ects gt^.

them. Again the fashion somethe necessary t.'^aversing.

times runs upon fancy twists, The spindle H is simply, and then it is necessary to be able to screwed into the frame- produce the various styles of cloud, loop, work, and does not re- curl, knop, &c., yarns. Twofolding is volve, but simply acts as done upon the flyer, cap and ring frames. a support for the cap and The main difference between the cap as a centre of motion for and the ring frame is that in the latter the tube and bobbin. a small bent piece of wire, termed a traveller, revolved round a ring by the pull of the spindle through the yarn, serves as the rctarder to enable the bobbin to wind the yarn, delivered by the front rollers on to itself (see fig. 19). Fancy twisters are almost universally on the ring system. Yarns are placed on the market in eight forms, viz. in hank, on spools, on paper tubes, on bobbins, on cops, in cheeses, in the warp Varus. ^ form and dressed upon the loom beam. Thus the manufacturer can order the yarn which he requires in the form best suited to his purpose. Although in some few cases special means must be employed for the weaving of woollens, worsteds and stuff goods, still the main Weaving, principles are the same for all classes of goods (see Weaving). Attention may here be concentrated on the characteristic principles of woollen and worsted manufacture. The characteristic feature of wool and of wool yarns and cloths is the quality of " felting." This quality has always been made use of in woollen cloths, but in worsted cloths, until comparapi„ishlaT tively recently, it has been largely ignored. To-day, processes however, cloths are made, ranging from the truest woollen to the typical worsted, of which it would be impossible to indicate the type of yarn employed without very careful analysis. As it is obviously impossible to give here every variety of finish WooHen cloth finishing. ^

B Fig. 18. — Section of French Drawing-Box. A, A', delivery rollers which control the slivers during the drafting operation. B is the porcupine (or circular gill) and C are the front drafting rollers. D is the funnel through which the slivers pass to the consolidating rubbers E, E, F is a second funnel and G is the condensed sliver wound up at a uniform rate on the roller H. employed, the two typical styles for woollen and worsted cloths are dealt with in detail, and further to elucidate the matter the finishing of a Bradford " stuff " or " lustre " piece is also given in outline. The fabric on leaving the loom is first mended and then scoured. The operation of scouring is effected in a " dolly, " and must thoroughly clear the piece so that it is free to take the desired finish. The piece is now soaped and " milled, " i.e. felted. Milling may be effected either in the stocks or in the milling machine. The stocks, the main features of which are huge hammers which are caused to fall or are driven positively into the cloth, exert a bursting action eliminating the thread structure. The milling machine acts more by compression, arrangements being made to compress the cloth in length or breadth at will. After milling scouring follows to clear the cloth thoroughly of the milling agents previous to the finishing proper. The cloth is now taken in a damp state to the tendering machine and, being hooked upon a frame running into a heated chamber, is stretched in width and dried in this condition. Raising follows, this being effected by subjecting the surface of the fabric to the action of " teazles " fixed on a large revolving cylinder, the whole machine being termed a " gig." After raising the fabric is " cropped " by being passed over a blade near which revolving knives work, on the principle of a lawn-mower, shearing and levelling the piece. Sometimes fabrics are rai£ed wet, especially if a velvet finish is required. Brushing follows to clear the piece of all stray fibres. The fabric is now ready for " crabbing, " which consists in winding it tightly on to a perforated roller through which steam may be blown or upon which the piece may be boiled. The pieces are then rewound Elevation r Fig. 19. — Section of Ring Spindle. A is the spindle suitably shaped to receive the bobbin at B, with a wharl for turning at C, running in the specially designed receptacle D, which may be screwed firmly into the spindle rail. The traveller E is drawn round the ring F by the spindle acting through the yam as shown in the plan. The spindle is a fixture and the ring-rail is traversed to distribute the yam on the bobbin. and the operation repeated at least once, to obtain even distribution of finish. Being now ready for pressing, the fabric is cuttled, usually

with press papers between each cuttle, and placed in the hydraulic

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