Part 8 (1/2)

=Cotton Mixing and the Bale Breaker.=--As before stated, the first operation in the mill is the opening out of bales of raw material and making a ”mixing.” Of course the weight of the bale is ascertained before it is opened.

All varieties of cotton vary in their commercial properties, this variation being due to a number of causes. From a commercial value point of view, there is an enormous difference between the very best and the very worst cottons; so much so, indeed, that they are never blended together. Between these two extremes there is a well-graded number of varieties and cla.s.sifications of cotton, and some approximate so closely to others in quality, that they are often blended together in the ”mixing.”

Further than this, the same cla.s.s of cotton often varies in spinning qualities from a number of circ.u.mstances that need not here be named.

This is, however, an additional reason why cotton from various bales should be blended together in order to secure uniformity.

A cotton ”mixing” may be described as a kind of ”stack,” resembling somewhat the haystack of the farm yards.

The method usually pursued in making this mixing is somewhat as follows:--A portion of cotton from a certain bale is taken off and spread over a given area of floor s.p.a.ce. Then a similar portion from another bale is placed over the first layer already lying on the floor.

The same operation is followed with a third and fourth layer from different bales, and so on with as many bales as the management consider there are variations in quality, the larger the mixing the better for securing uniformity of yarn.

When it is desired to use the cotton, it should be pulled down vertically from the face of the ”mixing,” so as to secure a fair portion from each bale composing the mixture. Before spreading the cotton out it is usually pulled into pieces of moderate size by the hands of the operative.

During recent years it has become the very general practice to use a small machine called the ”Bale Breaker” or ”Cotton Puller,” and to have also working in conjunction with this machine long travelling ”lattices”

called ”mixing lattices.” These perform the operation of ”pulling” and ”mixing” the cotton much more quickly and effectively than by hand labour.

The ”Cotton Puller” or ”Bale Breaker” (see Fig. 12) simply consists, in its most useful form, of four pairs of coa.r.s.ely fluted or spiked rollers of about 6 inches diameter with a feed ap.r.o.n or lattice such as is shown in the ill.u.s.tration.

Image: FIG. 12.--Bale breaker or puller.

The method adopted with the ”Bale Breaker” and ”mixing lattices” in use is as follows:--

The various bales of cotton intended for ”mixing” are placed very near to the feed ap.r.o.n of the Bale Breaker, and a layer from each bale in succession is placed on the ap.r.o.n. The latter feeds the cotton at a slow rate to the revolving rollers of the machine, and as each pair of top and bottom rollers that the cotton meets is revolving more rapidly than the preceding pair, the result is a pulling asunder of the cotton by the rollers, into much smaller pieces, quite suitable for the next machine.

The Bale Breaker delivers the cotton upon long travelling ap.r.o.ns of lattice work, which carry the cotton away and deposit it upon any desired portion of the floor to form the ”mixing.”

=Opening.=--The name of the next process, viz., ”opening,” has been given it because its primary function is ”to open” out the cotton to such an extent that the greater bulk of the seed, leaf, sand, and dust is readily extracted. The details of this machine and indeed practically of all machines used in cotton spinning, vary so much with different makers, that it would be utterly out of place to deal with them here, so that it may be said at once, that all such points are entirely omitted from this treatment of the subject.

The essential and princ.i.p.al portions of the machines are practically identical for all makers, and it is with these only that it is proposed to deal, taking in all cases the best present-day practice.

The opener, then, is a very powerful machine, being in fact the most powerful used in cotton spinning, and the most important feature of the machine is the employment of a strong beater, to which is fitted a large number of iron or steel knives or spikes. These beat down the cotton and open it at a terrific rate, the beater having a surface speed of perhaps 4000 feet a minute. Various fans, rollers, and other parts are employed to feed the cotton to the beater, and to take it away again after treatment. It will perhaps best serve the purpose of our readers if the pa.s.sage of the cotton be described through an opener of the most modern and approved construction, dealing with the subject in non-technical terms.

With this object in view, take for example what is termed ”The Double Cotton Opener” with ”Hopper Feed Attachment.” This machine is shown in Fig. 13.

Image: FIG. 13.--”Double opener” with ”hopper feed.”

The Hopper Feed is about the most recent improvement of any magnitude generally adopted in cotton spinning mills. It is an attachment to the initial or feed end of an opener with the object of feeding the cotton more cheaply and effectively than it can be done by hand.

It may be said to consist of a large iron feed box, into which the cotton is pa.s.sed in considerable quant.i.ties at one time. At the bottom of the feed box, or hopper, is a travelling ap.r.o.n which carries the cotton forward, so as to be brought within the action of steel pins in an inclined travelling ap.r.o.n or lattice. This latter carries the cotton upwards, and special mechanism is provided in the shape of what is termed an ”Evener roller,” to prevent too much cotton going forward at once.

The cotton that pa.s.ses over the top of the inclined lattice or ap.r.o.n is stripped off by what is denominated the stripping roller, and is then deposited on the feed ap.r.o.n of the opener, where formerly it was placed by hand.

It may be said that one man can feed two machines with Hopper Feeds as against one without them, and in the best makes the work is done more effectively.

The feed lattice of the opener carries the cotton along to the feed rollers, which project it forward into the path of the large beater. It is here that the opening and cleaning actions are chiefly performed.

The strong knives or spikes of the beater break the cotton into very small portions indeed, and dash it against ”cleaning bars” or ”grate bars” specially arranged and constructed. Through the interstices of these bars much of the now loosened seed and dirt present in the cotton pa.s.ses into a suitable receptacle, which is afterward cleaned out at regular intervals.