SELECTION / BATCHING
As jute grown in different areas varies in strength, color and fineness, the first step in preparing the fiber is “batching”, consisting of blending the various fibers to obtain uniformity in strength and color to give the precise quality of yarn for spinning. This involves the opening of various qualities of bales. These are then examined, sorted and mixed to form various batches.
In the first mechanical operation in the mill, the jute is fed into a softener in which the jute, treated with an emulsion oil and water, passes between sets of heavy spiral fluted rollers. This process renders the fiber thoroughly pliant and removes any barky portions adhering to the fiber. The piled jute is cut in order to remove the roots.
The fibers are then carded in machines, known as breaker cards and finisher cards, which reduces the average length of the fibers by teasing and combing,, and deliver them in the form of a long continuous ribbon, 5″ or 6″ in width, called sliver.
The carded jute is next fed into drawing machines in three stages through the first, second and third drawing frames which draw out and attenuate the sliver, parallelize the fibres, and by means of a doubling process, produce a smoother, more even sliver. However, in case of sacking weft, the passage through, drawing frame is only done twice i.e, through first and second drawing frames.
The last operation in the preparing department is spinning, a process which imparts a slight twist to the sliver and delivers the material on to bobbins in the form of rove, a loose yarn ready for spinning. The spinning machinery known as sliver spinning, an extra drawing operation delivers a crimped sliver, which can be fed direct to the sliver spinning form. Spinning frames convert the rove to finished yarn.
After spinning, the yarns are wound into the form required – spools for warp yarn and cops for weft yarn – for subsequent processing. Jute yarn is processed much like other textile fibers, the yarn itself being dressed (i.e, sized or starched), before being passed on to the warp beam ready for weaving.
Jute fabrics are of simple construction and are woven on a variety of looms. Woven fabrics are inspected, damped and calendared to produce the desired smoothness of finish.
The woven cloth is then folded in the desired length, packed in bales by hydraulic press, covered with gunny cloth for protection and stored in godowns (warehouses) to await shipment. Where jute goods are sold in the form of bags, the woven cloth is cut to the required size and then hemmed, sewn and hand stitched. These bags are folded and packed in bales. All such goods are then stored in the finished goods godown and are dispatched as per the delivery schedule.