SIZING AND DYEING MACHINE 



837 



This is 







SIZING AND DYEING MACHINE. The process of sizing and dyeing of 

 yarns has usually been effected by two processes. The yarn was dyed in the bale 

 warp, and in that state each thread was not equally exposed to the dye ; and then the 

 system of ball-warp sizing was adopted. Dawson and Slater have recently introduced 

 a new process, by which the yarn is both dyed and sized at the same time 

 effected by passing the yarn first through a solu- 

 tion of the colouring-matter, and the mordant held 

 in solution by some acid, then through ammo- 

 niacal vapour, and lastly through the size-box. 

 The process is as follows: Beginning with the 

 four-warp roller A A (at the right hand of the 

 machine ) as seen in fig. 1853), the yarn passes 

 thence into the dye-vessel B, over three guide- 

 rollers to a copper cylinder c, thence over another 

 guide-roller to a second copper cylinder, eventu- 

 ally coming up through the two squeezing rollers 

 D, at the end of the dye-box. It may be observed, 

 that the copper cylinders can be raised or lowered 



in the dye-box by means of a rack and pinion, 



and that the small circles at the bottom of the 



dye-vessel represent steam-pipes for boiling the 



dye-liquor. The yarn then passes from the squeez- 

 ing rollers over other rollers into the ammoniacal 



or gas-chamber E, which, with the exception of _ 



two openings, the one for the passing in of the 



yarn, and the other for letting it out, is wholly 



closed by the lid here represented in the centre of 



the chamber. By following the dotted lines, it 



will be perceived that herein the yarn passes under 



and over four guide-rollers before its exit from 



the chamber, it being during the passage fully 



exposed to the vapour of the ammonia, which is 



introduced by means of the funnel represented in 



the centre. Thence the yarn passes into the next 



vessel termed the washing-box or chamber, over 



and under suitable rollers and through the two 



squeezing rollers at the end, there being a perfo- 

 rated pipe, not shown in the drawing, for dis- 

 charging water on to the yarn. Coming out of the 



washing-box, the yarn continues its journey over 



a steam-drying cylinder F, down into the size-box 



G below, the smaller circle in the engraving repre- 

 senting a guide-roller, and the others two copper 



squeezing rollers. Then the yarn, after leaving 



the squeezing rollers, passes over and under a 



larger cylinder H, and a smaller drying cylinder i, 



whence it is conveyed by suitable rollers to the 



weaver's beam as marked. 



The advantages of this arrangement are that 



the yarn is less strained, less crossed, and in a 



better condition for weaving. It enters the size 



and the dye in the form of a sheet, in which state 



each thread is separated, and completely sur- 

 rounded by the dye, and afterwards by the size ; 



the result is uniformity of shade and an absence of 



streaky or uneven places. Not only so, but there 



is a great saving of time, for warps in the grey 



in the morning may be dyed, sized, and in the loom 



weaving by noon of the same day, and all done on 



the manufacturer's own premises and under his 

 supervision, contrasting very favourably with the old plan of getting the work done out 

 of doors. By that system the time that elapses from sending the warps to the dyer 

 to receiving them back again is frequently ten clays to a fortnight, which necessitates 

 the keeping of a larger stock than is requisite by the new plan, when all is done in a 

 few hours. 



To illustrate the principle of these improvements, one example will suffice. Sup- 

 pose that a black dye is required; a coloured solution is made by boiling about 100 



