Figure 27 shows a washing machine very largely used in the wool-dyeing trade. The principal portion of this machine is of wood.
The internal parts consist of a large wooden bowl, or oftener, as in the machine under notice, of a pair of wooden bowls which are pressed together by springs with some small degree of force. Between these bowls the cloth is placed, more or less loosely twisted up in a rope form, and the machines are made to take four, six or eight pieces or lengths at one time, the ends of the pieces being stitched together so as to make a continuous band. A pipe running along the front of the machine conveys a constant current of clean water, which is caused to impinge in the form of jets on the pieces of cloth as they run through the machine, while an overflow carries away the used water. The goods are run in this machine as long as is considered necessary for a sufficient wash, which may take half to one and a half hours.
In figure 30 is shown a machine designed to wash pieces in the broad or open state. The machine contains a large number of guide rollers built more or less open, round which the pieces are guided, the ends of the pieces being stitched together, pipes carrying water are so arranged that jets of clean water impinge on and thoroughly wash cloth as it passes through, the construction of the guide rollers facilitating the efficient washing of the goods.
Soaping.
Sometimes yarns or cloths have to be passed through a soap-bath after being dyed in order to brighten up the colours or develop them in some way. In the case of yarns this can be done on the reel washing machines such as are shown in figure 25. In the case of piece goods a continuous machine in which the washing, soaping, etc., can be carried on simultaneously is often employed. Such a machine is shown in figure 28. It consists of a number of compartments fitted with guide rollers, so that the cloth passes up and down several times through the liquors in the compartment; between one compartment and another is placed a pair of squeezing rollers. The cloth is threaded in a continuous manner, well shown in the drawing, through the machine; in one compartment it is treated with water, in another with soap liquor, and another with water, and so on, and these machines may be made with two, three or more compartments, as may be necessary for the particular work in hand. As seen in the drawing the cloth passes in at one end, and out at the other finished. It is usually arranged that a continuous current of the various liquors used flows through the various compartments, thus ensuring the most perfect treatment of the cloths.
Following on the washing comes the final operation of the dyeing process, that of drying the dyed and washed goods. Now textile fabrics of all kinds after they have passed through dye-baths, washing machines, etc., contain a large amount of water, often exceeding in amount that of the fabric itself, and to take the goods direct from the preceding operations to the drying plant means that a considerable amount of fuel must be expended to drive off this large amount of water. It is therefore very desirable that the goods be freed from as much of this water as possible before they are sent into any drying chambers, and this may be done in three ways, by wringing, squeezing and hydro-extracting. The first two methods have already been described (pp. 198, 199) and need not again be alluded to, the last needs some account.