The Jute Industry: From Seed to Finished Cloth by T. Woodhouse and P. Kilgour
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T. Woodhouse and P. Kilgour >> The Jute Industry: From Seed to Finished Cloth
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In normal years there is also a large quantity of fibre of a better
quality than what is known as "first mark," and this better quality
is termed "fine jute"; while there is yet a further lot, the quality
of which is below these good ones. Since there are hundreds of
different marks which are of value only to those connected directly
with the trade, it is unnecessary to dwell on the subject. The
following list, however, shows quotations of various kinds, and is
taken from the Market Report of the Dundee Advertiser of March, 1920.
The price of jute, like almost everything else, was at this date
very high, so in order to make comparisons with the 1920 and normal
prices, we introduce the prices for the corresponding grade, first
marks, for the same month in the years 1915 onwards.
JUTE PRICES, IN MARCH
First Marks
Year. Price per ton.
L. s. d. L. s. d.
1915 27 to 35 15
1916 44
1917 42 10
1918 51
1919 49
1920 70 (spot)
It is necessary to state that the assorting and balings are
generally so uniform that the trade can be conducted quite
satisfactorily with the aid of the usual safeguards under contract,
and guarantees regarding the properties of the fibre.
After these assorting operations are completed, the jute fibre is
made up into bundles or "bojahs" of 200 lbs. each, and two of these
200 lb. bundles are subsequently made up into a standard bale, the
weight of which is 400 lbs. This weight includes a permitted
quantity of binding rope, up to 6 lbs. in weight, while the
dimensions in the baling press of the 400 lb. bale are 4'1" X 1'6" X 1'
4".
[Illustration: FIG. 4 NATIVES CARRYING SMALL BALES OF JUTE FIBRE
FROM BOAT TO PRESS HOUSE]
Large quantities of the smaller and loosely-packed bales are
conveyed from the various places by boats to the baling houses or
press houses as they are termed. These are very large establishments,
and huge staffs of operatives are necessary to deal rapidly and
efficiently with the large number of bales. In Fig. 4 scores of
natives, superintended by a European, are seen carrying the smaller
bales on their heads from the river boat to the press house. It is,
of course, unnecessary to make the solid 400 lb. bales for Indian
consumption; this practice is usually observed only for jute which
is to be exported, and all such bales are weighed and measured at
the baling station by a Chamber of Commerce expert.
Most of the baling presses used in the press houses in the Calcutta
district are made in Liverpool, and are provided with the most
efficient type of pumps and mechanical parts. Fig. 5 illustrates one
of these huge presses with a number of natives in close proximity.
Two or three distinct operations are conducted simultaneously by
different groups of operatives, and ingenious mechanism is essential
for the successful prosecution of the work. Two such presses as that
illustrated in Fig. 5 are capable, under efficient administration, of
turning out 130 bales of 400 lbs. each in one hour. The fibre is
compressed into comparatively small bulk by hydraulic pressure equal
to 6,000 lbs. per square inch, and no packed bale must exceed in
cubical capacity 11 cubic feet after it leaves the press; it is
usual for freight purposes to reckon 5 bales or 55 cubic feet per ton.
(Now changed to 50 cubic feet.)
The jute bales are loaded either at the wharf or in the river from
barges into large steamers, many of which carry from 30,000 to
46,000 bales in one cargo to the European ports. One vessel brought
70,000 bales.
As already mentioned, jute is sold under guarantees as to quality,
and all disputes must be settled by arbitration. Although this is
the usual method of sale, it is not uncommon for quantities of jute
to be shipped unsold, and such quantities may be disposed of on the
"Spot." It is a common practice to sell a number of bales to sample,
such number depending generally upon the extent of the quantity, or
"parcel," as it is often called. The contract forms are very complete,
and enable the business to be conducted to the satisfaction of all
concerned in the trade.
[ILLUSTRATION: FIG. 5 NATIVES BAILING JUTE FIBRE IN A WATSON-FAWCETT
CYCLONE PRESS]
It will be understood that, in the yearly production of such a large
quantity of jute fibre from various districts, and obtained from
plants which have been grown under variable climatic and
agricultural conditions, in some cases the fibre will be of the
finest type procurable, while in other cases it will be of a very
indifferent type and unsuitable for use in the production of the
ordinary classes of yarns and fabrics. On the other hand, it should
be stated that there is such a wide range of goods manufactured, and
additional varieties occasionally introduced, that it appears
possible to utilize all the kinds of fibre in any year; indeed, it
seems as if the available types of fibre each season create demands
for a corresponding type of manufactured product.
The crops produced will, obviously, vary in amount and value annually,
but a few figures will help the reader to estimate in some degree
the extent of the industry and its development in various parts of
the world.
EXPORTS OF JUTE FROM INDIA
Year. Tons. Bales.
1828 18 300 lbs/bale
1832 182 300 lbs/bale
1833 300 300 lbs/bale
1834 828 300 lbs/bale
1835 1,222 300 lbs/bale
1836 16 300 lbs/bale
1837 171 300 lbs/bale
[Illustration: FIG. 6 VESSEL LADEN WITH JUTE AT QUAY-SIDE ADJOINING
JUTE SHEDS IN DUNDEE HARBOUR]
JUTE PRODUCTION IN INDIA
Season. Tons. Bales (400 lbs.).
1850-51. 28,247 158,183
1860-61. 46,182 258,619
1862-63. 108,776 609,146
1863-64. 125,903 707,056
1872-73. 406,335 2,275,476
1880-81. 343,596 1,924,137
1886-87. 413,664 2,316,518
1892-93. 586,258 3,083,023
1896-97. 588,141 3,293,591
1902-03. 580,967 3,253,414
1906-07. 829,273 4,643,929
1907-08. 1,761,982 9,867,100
1908-09. 1,135,856 6,360,800
1909-10. 1,302,782 7,295,580
1910-11 1,434,286 8,032,000
1911-12. 1,488,339 8,334,700
1912-13. 1,718,180 9,621,829
1913-14. 1,580,674 8,851,775
1914-15. 1,898,483 10,631,505
1915-16. 1,344,417 7,528,733
1916-17. 1,493,976 8,366,266
1917-18. 1,607,922 9,004,364
1918-19. 1,278,425 7,159,180
1919-20. 1,542,178 8,636,200
A large vessel containing bales of jute is berthed on the quay-side
adjoining the jute sheds in Fig. 6. The bales are raised quickly
from the hold by means of a hydraulic-engine, scarcely visible in Fig.
6 since it is at the far end of the vessel, but seen clearly in Fig.
7. When the bales are raised sufficiently high, they are guided to
the comparatively steep part of a chute from which they descend to
the more horizontal part as exemplified in Fig. 7. They are then
removed by means of hand-carts as shown, taken into the shed, and
piled or stored in some suitable arrangement with or without the aid
of a crane. Motor and other lorries are then used to convey the bales
to the various mills where the first actual process in what is termed
spinning takes place. It will be understood that the bales are stored
in the spinner's own stores after having been delivered as stated.
[Illustration: FIG. 7. HARBOUR PORTERS REMOVING BALES OF JUTE FROM
THE VESSEL SHOWN IN FIG. 6]
CHAPTER V. MILL OPERATIONS
_Bale Opening_. Each spinner, as already indicated, stores his
bales of jute of various "marks," i.e. qualities, in a convenient
manner, and in a store or warehouse from which any required number
of bales of each mark can be quickly removed to the preparing
department of the mill.
In the woollen industry, the term "blending" is used to indicate the
mixing of different varieties of material (as well as different
kinds of fibres) for the purpose of obtaining a mixture suitable for
the preparing and spinning of a definite quality and colour of
material. In much the same way, the term "batching" is used in the
jute industry, although it will be seen shortly that a more
extensive use is made of the word. A "batch," in its simplest
definition, therefore indicates a number of bales which is suitable
for subsequent handling in the Batching Department. This number may
include 5, 6, 7 or more bales of jute according to the amount of
accommodation in the preparing department.
All the above bales of a batch may be composed of the same standard
quality of jute, although the marks may be different. It must be
remembered that although the marks have a distinct reference to
quality and colour, they actually represent some particular firm or
firms of balers or merchants. At other times, the batch of 5 to 10
bales may be composed of different qualities of jute, the number of
each kind depending partly upon the finished price of the yarn,
partly upon the colour, and partly upon the spinning properties of
the combination.
It will be understood that the purpose for which the finished yarn
is to be used will determine largely the choice of the bales for any
particular batch. For example, to refer to a simple differentiation,
the yarn which is to be used for the warp threads in the weaving of
cloth must, in nearly every case, have properties which differ in
some respects from the yarn which is to be used as weft for the same
cloth.
On the whole, it will be found advantageous, when the same grade of
jute is required, to select a batch from different balers' marks so
that throughout the various seasons an average quality may be
produced. The same class of yarn is expected at all times of the year,
but it is well known that the properties of any one mark may vary
from time to time owing to the slight variations in the manipulation
of the fibre at the farms, and to the variations of the weather
during the time of growth, and during the season generally.
A list of the bales for the batch is sent to the batching department,
this list being known as a "batch-ticket." The bales are, of course,
defined by their marks, and those mentioned on the batch-ticket must
be rigidly adhered to for one particular class of yarn; if there is
any chance of one kind running short, the condition should be
notified in time so that a suitable mark may be selected to take its
place without effecting any great change in the character or quality
of the yarn.
When the number and kind of bales have been selected and removed
from the groups or parcels in the store or warehouse, they are
conveyed to the batching department, and placed in a suitable
position near the first machine in the series. It need hardly be
mentioned that since the fibre, during the operation of baling, is
subjected to such a high hydraulic pressure, the bale presents a
very solid and hard appearance, see Fig. 7, for the various
so-called "heads" of fibre have been squeezed together and forced
into a very small bulk. In such a state, the heads are quite
unfitted for the actual batching operation; they require to be opened
out somewhat so that the fibres will be more or less separated from
each other. This operation is termed "opening" and the process is
conducted in what is known as a "bale opener," one type of which is
illustrated in Fig. 8, and made by Messrs. Urquhart, Lindsay & Co.,
Ltd., Dundee.
The various bales of the batch are arranged in a suitable manner
near the feed side of the machine, on the left in the view, so that
they can be handled to the best advantage. The bands or ropes, see
Fig. 7, are removed from the bale in order that the heads or large
pieces of jute can be separated. If any irregularity in the
selection of the heads from the different bales of the batch takes
place in this first selection of the heads of jute, the faulty
handling may affect subsequent operations in such a way that no
chance of correcting the defect can occur; it should be noted at
this stage that if there are slight variations of any kind in the
fibres, it is advisable to make special efforts to obtain a good
average mixture; as a matter of fact, it is wise to insist upon a
judicious selection in every case. The usual variations are--the
colour of the fibre, its strength, and the presence of certain
impurities such as stick, root, bark or specks; if the pieces of jute,
which are affected adversely by any of the above, are carefully
mixed with the otherwise perfect fibre, most of the faults may
disappear as the fibre proceeds on its way through the different
machines.
[Illustration: FIG. 8 BALE OPENER _By permission of Messrs. Urquhart,
Lindsay & Co., Ltd_.]
The layers of heads are often beaten with a heavy sledge hammer in
hand batching, but for machine batching a bale opener is used, and
this operation constitutes the preliminary opening. As already
indicated, the heads of jute are fed into the machine from the left
in Fig. 8, each head being laid on a travelling feed cloth which
carries the heads of jute successively between a pair of feed
rollers from which they are delivered to two pairs of very
deeply-fluted crushing rollers or breakers. The last pair of
deep-fluted rollers is seen clearly on the right in the figure.
These two pairs of heavy rollers crush and bend the compressed heads
of jute and deliver them in a much softer condition to the delivery
sheet on the right. The delivery sheet is an endless cloth which has
a continuous motion, and thus the softened heads are carried to the
extreme right, at which position they are taken from the sheet by
the operatives. The upper rollers in the machine may rise in their
bearings against the downward pressure of the volute springs on the
bearings; this provision is essential because of the thick and thin
places of the heads.
A different type of bale opener, made by Messrs. Charles Parker, Sons, &
Co., Dundee, and designed from the Butchart patent is illustrated in
Fig. 9. It differs mainly from the machine illustrated in Fig. 8 in
the shape of the crushing or opening rollers.
It will be seen on referring to the illustration that there are
three crushing rollers, one large central roller on the top and
situated between two lower but smaller rollers. Each roller has a
series of knobs projecting from a number of parallel rings. The
knobs are so arranged that they force themselves into the hard
layers of jute, and, in addition to this action, the heads of jute
have to bend partially round the larger roller as they are passing
between the rollers. This double action naturally aids in opening up
the material, and the machine, which is both novel and effective,
gives excellent results in practice. The degree of pressure provided
for the top roller may be varied to suit different conditions of heads
of jute by the number of weights which are shown clearly in the
highest part of the machine in the form of two sets of heavy discs.
[Illustration: FIG. 9 BALE OPENER _By permission of Messrs. Charles
Parker, Sons, & Co_.]
The driving side, the feed cloth, and the delivery cloth in this
machine are placed similarly to the corresponding parts of the
machine illustrated in Fig. 8, a machine which also gives good
results in practice.
In both cases the large heads are delivered in such a condition that
the operatives can split them up into pieces of a suitable size
quite freely.
The men who bring in the bales from the store take up a position
near the end of the delivery cloth; they remove the heads of jute as
the latter approach the end of the table, and then pass them to the
batchers, who split them. The most suitable size of pieces are 2-1/2
to 3 lbs. for a piece of 7 feet to 8 feet in length, but the size of
the pieces is regulated somewhat by the system of feeding which is
to be adopted at the breaker-card, as well as by the manager's
opinion of what will give the best overall result.
After the heads of jute have been split up into suitable smaller
pieces, they are placed in any convenient position for the batcher
or "striker-up" to deal with. If the reader could watch the above
operation of separating the heads of jute into suitable sizes, it
would perhaps be much easier to understand the process of
unravelling an apparently matted and crossed mass of fibre. As the
loosened head emerges from the bale-opener, Figs. 8 or 9, it is
placed over the operative's arm with the ends of the head hanging,
and by a sort of intuition acquired by great experience, she or he
grips the correct amount of fibre between the fingers, and by a
dexterous movement, and a simultaneous shake of the whole piece, the
handful just comes clear of the bulk and in much less time than it
takes to describe the operation.
As the pieces are thus detached from the bulk, they are laid on
stools or tables, or in stalls or carts, according to the method by
means of which the necessary amount of oil and water is to be added
for the essential process of lubrication; this lubrication enables
the fibre to work freely in the various machines.
CHAPTER VI. BATCHING
_Softening and Softening Machines_. Two distinct courses are
followed in the preparation of the jute fibre after it leaves the
bale opener, and before it is carded by the breaker card. These
courses are designated as--
1. Hand Batching.
2. Machine Batching.
In the former process, which is not largely practised, the pieces of
jute are neatly doubled, while imparting a slight twist, to
facilitate subsequent handling, and laid in layers in large carts
which can be wheeled from place to place; if this method is not
convenient, the pieces are doubled similarly and deposited in large
stalls such as those illustrated in Fig. 10.
On the completion of each layer, or sometimes two layers, the
necessary measured amount of oil is evenly sprayed by hand over the
pieces from cans provided with suitable perforated outlets--usually
long tubes. After the oil has been added, water, from a similar
sprayer attached by tubing to a water tap, is added until the
attendant has applied what he or she considers is the proper quantity.
The ratio between a measured amount of oil and an unmeasured amount
of water is thus somewhat varied, and for this reason the above
method is not to be commended. A conscientious worker can, however,
with judgment, introduce satisfactory proportions which are, of
course, supplied by the person in charge. In Fig. 10, the tank on
the right is where the oil is stored, while the oil can, and the
spray-pipe and tube for water, are shown near the second post or
partition on the right.
[ILLUSTRATION: FIG. 10 HAND-BATCHING DEPARTMENT WITH UNPREPARED AND
PREPARED FIBRE]
The first stall--that next to the oil tank--in Fig. 10 is filled
with the prepared pieces, and the contents are allowed to remain
there for some time, say 24 hours, in order that the material may be
more or less uniformly lubricated or conditioned. At the end of this
time, the pieces are ready to be conveyed to and fed into the
softening machines where the fibres undergo a further process of
bending and crushing.
All softening machines for jute, or softeners as they are often
called, are similar in construction, but the number of pairs of
rollers varies according to circumstances and to the opinions of
managers. Thus, the softener illustrated in Fig. 11, which, in the
form shown, is intended to treat jute from the above-mentioned stalls,
is made with 47, 55, 63 or 71 pairs of rollers or any other number
which, minus 1, is a measure of 8. The sections are made in 8's. The
illustration shows only 31 pairs.
The first pair of rollers--that next to the feed sheet in the
foreground of Fig. 11--is provided with straight flutes as clearly
shown. All the other rollers, however, are provided with oblique
flutes, such flutes making a small angle with the horizontal. What
is often considered as a standard softening machine contains 63
pairs of fluted rollers besides the usual feed and delivery rollers.
As mentioned above, this number is varied according to circumstances.
The lubricated pieces of jute are fed on to the feed roller sheet,
and hence undergo a considerable amount of bending in different ways
before they emerge from the delivery rollers at the other end of the
machine.
[Illustration: Fig. 11 Softening machine without batching apparatus]
Machine batching is preferred by many firms because the application
of oil and water, and the proportion of each, are much more uniform
than they are by the above mentioned process of hand batching. On the
other hand, there is no time for conditioning the fibre because the
lubrication and the softening are proceeding simultaneously,
although conditioning may proceed while the fibre remains in the
cart after it has left the softener.
The mechanical apparatus as made by Messrs. Urquhart, Lindsay & Co.,
Ltd., Dundee, for depositing the oil and water on the pieces or
"stricks" of jute is illustrated in Fig. 12. The actual lubricating
equipment is situated on the top of the rectangular frame in the
centre of the illustration. This frame is bolted to the side frames
of the softening machine proper, say that shown in Fig. 11. Its
exact position, with respect to its distance from the feed, is a
matter of choice, but the liquid is often arranged to fall on to the
material at any point between the second and twelfth rollers.
In Fig. 12 the ends of 13 rollers of the upper set are seen clearly,
and these upper rollers are kept hard in contact with the stricks or
pieces of jute by means of the powerful springs shown immediately
above the roller bearings and partially enclosed in bell-jars.
Outside the rectangular frame in Fig. 12 are two rods, one vertical
and the other inclined. The straight or vertical rod is attached by
suitable levers and rods to the set-on handles at each end of the
machine and to the valve of the water pipe near the top of the frame,
while the upper end of the inclined or oblique rod is fulcrumed on a
rod projecting from the frame. The lower or curved end of the
oblique rod rests against the boss of one of the upper rollers.
[Illustration: Fig. 12]
The water valve is opened and closed with the starting and stopping
of the machine, but the oblique rod is moved only when irregular
feeding takes place. Thus, the upper rollers rise slightly against
the pressure of the springs when thick stricks appear; hence, when a
thick place passes under the roller which is in contact with the
curved end of the oblique rod, the end moves slightly clockwise, and
thus rotates the fulcrum rod; this results in an increased quantity
of oil being liberated from the source of supply, and the mechanism
is so arranged that the oil reaches the thick part of the strick.
When the above-mentioned upper roller descends, due to a decrease in
the thickness of the strick, the oblique rod and its fulcrum is
moved slightly counter-clockwise, and less oil is liberated for the
thin part of the strick. It will be understood that all makers of
softening machines supply the automatic lubricating or batching
apparatus when desired.
A view of a softener at work appears in Fig. 13. The bevel wheels at
the end of the rollers are naturally covered as a protection against
accidents. In many machines safety appliances are fitted at the feed
end so that the machine may be automatically stopped if the
operative is in danger. The batching apparatus for this machine is
of a different kind from that illustrated in Fig. 12; moreover, it
is placed nearer the feed rollers than the twelfth pair. The feed
pipes for the oil and the water are shown coming from a high plane,
and the supply is under the influence of chain gearing as shown on
the right near the large driving belt from the drum on the shafting.
The feed roller in this machine is a spirally fluted one, and the
nature of the flutes is clearly emphasized in the view. The barrow
of jute at the far end of the machine is built up from stricks which
have passed through the machine, and these stricks are now ready for
conditioning, and will be stored in a convenient position for future
treatment.
[Illustration: Fig. 13 Softening machine with batching apparatus]
While the jute as assorted and baled for export from India is graded
in such a way that it may be used for certain classes of yarn
without any further selection or treatment, it may be possible to
utilize the material to better advantage by a judicious selection
and treatment after it has undergone the operation of batching.
What are known as cuttings are often treated by a special machine
known as a "root-opener." The jute cuttings are fed into the
machines and the fibre rubbed between fixed and rotating pins in
order to loosen the matted ends of stricks. Foreign matter drops
through the openings of a grid to the floor, and the fibre is
delivered on to a table, or, if desired, on to the feed sheet of the
softener.
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