THE PREPARING AND SPINNING MACHINERY FOR MANILA AND OTHER HARD FIBRES
The method of producing yarns from the hard fibres involves the use of
quite different machines in the preparatory processes; this departure is
necessary on account of the nature of the material and the length of the
raw fibre.
The bales of raw material, Manila, Sisal, New Zealand, or the like, but
all from one type in general, are arranged in a convenient position near
the feed of the first machine which is called a “Hackler and Spreader,”
and one type of which is illustrated in Fig. 25. The bales which are
grouped together for this first treatment are chosen from different
“marks” or grades of fibre in order to mix them to secure uniformity and
to produce yarns of a given quality at the desired price.
[Illustration: FIG. 25
HACKLER AND SPREADER]
The heads of material are split up into suitable and uniform stricks,
and when various classes are to be mixed it is essential that
proportionate quantities should be drawn from the various bales in the
“batch” or blend, and fed proportionately and uniformly on to the feed
sheet of the machine. The feed sheet conveys the stricks slowly towards
and ultimately between a pair of retaining and feed rollers, and when
the material emerges from these rollers it is acted upon by a series of
large hackle pins fixed in a chain of fallers or bars. These pins move
at twice the speed of the feed and retaining rollers, and this relative
movement enables the pins to hackle and open out the stricks. The
partially-hackled stricks are now conveyed to a second chain of fallers
and hackles which move at a much greater speed than that of the first
hackles; it is here where most of the drawing takes place, and the
material as it leaves these hackles is in the form of a thin sheet of
fibres which enters a pair of drawing rollers. Finally, the material is
delivered on to the floor in the form of a sliver and at the opposite
end of the machine.
The bundles of sliver are conveyed to another machine, termed the
intermediate machine, where further processes of equalization and
drawing take place. In this, and in any subsequent machine of the same
type, of which there may be three or four, the slivers are fed as
illustrated on the left of Fig. 26, while several lengths of slivers
appear in the foreground. After the drawing and hackling operations, the
sliver is delivered as illustrated. These processes prepare suitable
slivers for the remainder of the operations which are somewhat similar
to those which are used for the soft fibres, although the “reach” in the
machines for the hard fibres is very much longer than that necessary for
the soft fibres. In the final preparing machine, the sliver is delivered
into sliver cans which are then taken to the automatic spinning frame.
[Illustration: FIG. 26
INTERMEDIATE MACHINE]
AUTOMATIC SPINNING MACHINES.--A row of automatic spinning machines is
illustrated in Fig. 27. The slivers from the last drawing frame are
placed at the feed, one sliver can with its length of sliver for each
machine. The sliver is passed through the first conductor, situated
about a yard above the sliver can, and then between a pair of feed
rollers seen to the right of the machine. From here the sliver is
deflected to the proper bell-mouth conductor and to the long stretch or
reach of gill pins shown clearly in the view. On emerging from the gill
pins, the sliver passes through a nipping die and thence to the enclosed
flyer from which it is wound on to the bobbin.
[Illustration: FIG. 27
AUTOMATIC SPINNING MACHINE]
The drafting is accomplished by a series of rollers or pulleys which
draw the fibres through the gill pins and the nipping die, while the
twist is imparted as usual by the flyers which revolve at about 1,400
revolutions per minute. The flyers are now enclosed in a safety cage of
about the same width as the name plate.
The yarns thus spun are built upon large steel-ended bobbins which, when
filled, may be conveyed direct to the transferring or warping machines
where the yarns are prepared for further treatment, if and when any
further treatment is necessary, or to the rope machines. Thus, if the
yarns are to be made up into a tarred rope, it is necessary to prepare
them into a suitable form for the tarring operation. This usually takes
the form of a warp, and such warps are most satisfactorily made on a
warping mill or winding reel. It is usual to run twelve threads from
twelve bobbins and to make the warp a suitable size by continuing the
operation of warping in the same way as is done for warps which are to
be woven in a loom.
The warp is then passed through a tarring machine in which the tar,
usually Russian or Swedish, is kept warm during the operation. After the
necessary amount of tar has been applied, it is usual to store the warps
of yarn for a lengthened period, say up to six months, to condition
them. The individual yarns from these warps are then rewound on to
twelve large bobbins in what is known as a 12-bobbin vertical
spindle-winding machine.