Operations Following Dyeing Washing Soaping Drying


After loose wool, or woollen yarns or piece goods of every description

have been dyed, before they can be sent out for sale they have to pass

through various operations of a purifying character. There are some

operations through which cloths pass that have as their object the

imparting of a certain appearance and texture to them, these are

generally known as finishing processes, of these it is not intended

here to spea
, but only of those which precede them but follow on the

dyeing operations.



These processes are usually of a very simple character, and common to

most colours which are dyed, and here will be noticed the appliances

and manipulations necessary in the carrying out of these operations.



#Squeezing or Wringing.#--It is advisable when the goods are taken out

of the dye-bath to squeeze or wring them according to circumstances in

order to express out all surplus dye-liquor, which can be returned to

the dye-bath if needful to be used again. This is an economical

proceeding in many cases, especially in working with many of the old

tannin materials, like sumac, divi-divi, myrobalans, and the modern

direct dyes, which during the dyeing operations are not completely

extracted out of the bath, or in other words the dye-bath is not

exhausted of colouring matter, and therefore it can be used again for

another lot of goods simply by adding fresh material to make up for

that absorbed by the first lot.



Loose wool and loose cotton are somewhat difficult to deal with by (p. 198)

squeezing or wringing, but the material may be passed through a pair

of squeezing rollers such as are shown in figure 24, which will be

more fully dealt with later on.



#Yarns in Hanks.#--In the hand-dyeing process of hank-dyeing the hanks

are wrung by placing one end of the hank on a wringing-horse placed

over the dye-tub, and a dye-stick in the other end of the hank, giving

two or three sharp pulls to straighten out the yarn and then twisting

the stick round; the twisting of the yarns puts some pressure on the

fibres thoroughly and uniformly squeezing out the surplus liquor from

the yarn.



#Hank-Wringing Machines.#--Several forms of hank-wringing machines have

been devised. One machine consists of a pair of discs fitted on an

axle, these discs carry strong hooks on which the hanks are placed.

The operator places a hank on a pair of the hooks. The discs revolve

and carry round the hank, during the revolution the hank is twisted

and the surplus liquor wrung out, when the revolution of the discs

carries the hank to the spot where it entered the machine, the hooks

fly back to their original position, the hank unwinds, it is then

removed and a new hank put in its place, and so the machine works on,

hanks being put on and taken off as required. The capacity of such a

machine is great and the efficiency of its working good.



Mr. S. Spencer, of Whitefield, makes a hank-wringing machine which

consists of a pair of hooks placed over a vat. One of the hooks is

fixed, the other is made to rotate. A hank hung between the hooks is

naturally twisted and all the surplus liquor wrung out, the liquor

falling into the vat.



#Roller Squeezing Machines for Yarn.#--Hanks may be passed through a

pair of indiarubber squeezing rollers which may be so arranged that

they can be fixed as required on the dye-bath. Such a pair of (p. 199)

rollers is a familiar article and quite of common and general use in

dye-houses.



#Piece Goods.#--These are generally passed open through a pair of

squeezing rollers, which are often attached to the dye-vat in which

the pieces are dyed.



[Illustration: Fig. 24.--Read Holliday's Yarn-squeezing Machine.]



#Read Holiday's Squeezing Machine.#--In figure 24 is shown a squeezing

machine very largely employed for squeezing all kinds of piece goods

after dyeing or washing. It consists of a pair of heavy rollers on

which, by means of the screws shown at the top, a very considerable

pressure can be brought to bear. The piece is run through the eye

shown on the left, by which it is made into a rope form, then over

the guiding rollers and between the squeezing rollers and into (p. 200)

waggons for conveyance to other machines. This machine is effective.



Another plan on which roller, or rather in this case disc, squeezing

machines are made is to make the bottom roller with a square groove in

the centre, into this fits a disc, the cloth passing between them. The

top disc can, by suitable screws, be made to press upon the cloth in

the groove and thus squeeze the water out of it.



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