FIG. 41 CROPPING MACHINE AT WORK
The cloth is tensioned either by threading it over and under a series of stout rails, or else between two in a specially adjustable arrangement by means of which the tension may be varied by rotating slightly the two rails so as to alter the angle formed by the cloth in contact with them. This is, of course, at the feed side; the cloth is pulled through the machine by three rollers shown distinctly on the right in Fig. 42. This view illustrates a double cropper in which both the spirals are controlled by one belt. As the cloth is pulled through, both sides of it are cropped by the two spirals.[3] When four spirals are required, the frame is much wider, and the second set of spirals is identical with those in the machines illustrated.
FIG. 42 DOUBLE CROPPING MACHINE
By permission of Messrs. Charles Parker, Sons & Co., Ltd.
[Footnote 3: For a full description of all finishing processes, see The Finishing of Jute and Linen Fabrics, by T. Woodhouse. (Published by Messrs. Emmott & Co., Ltd., Manchester.)]
The cropped cloth is now taken to the clamping machine, and placed on the floor on the left of the machine illustrated in Fig. 43, which represents the type made by Messrs. Charles Parker, Sons &, Co., Dundee. The cloth is passed below a roller near to the floor, then upwards and over the middle roller, backwards to be passed under and over the roller on the left, and then forwards to the nip of the pulling rollers, the bottom one of which is driven positively by means of a belt on the pulleys shown. While the cloth is pulled rapidly through this machine, two lines of fine jets spray water on to the two sides of the fabric to prepare it for subsequent processes in which heat is generated by the nature of the finishing process. At other times, or rather in other machines, the water is distributed on the two sides of the cloth by means of two rapidly rotating brushes which flick the water from two rollers rotating in a tank of water at a fixed level. In both cases, both sides of the fabric are "damped," as it is termed, simultaneously. The damped fabric is then allowed to lie for several hours to condition, that is, to enable the moisture to spread, and then it is taken to the calender.
FIG. 43 DAMPING MACHINE
By permission of Messrs. Charles Parker, Sons & Co., Ltd.
The calenders for jute almost invariably contain five different rollers, or "bowls," as they are usually termed; one of these bowls, the smallest diameter one, is often heated with steam. A five-bowl calender is shown on the extreme right in Fig. 41, and in the background, while a complete illustration of a modern 5-bowl calender, with full equipment, and made by Messrs. Urquhart, Lindsay & Co., Ltd., Dundee, appears in Fig. 44.
