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Machine-made
carpets are tufted, woven, knitted,
flocked or needle-punched. Most commonly
tufting is used for machine-made
carpets. Tufted carpets are made on
machines where the yarn is stitched
through a pre-constructed backing to
form a loop or a tuft. To hold the loops
in place, the back side of the carpet is
coated with latex.
Tufting is the most inexpensive and
fastest ways to manufacture a rug.
Weavers can also control the tuft size
making it possible to create carpets
with varying patterns or surface
textures.
There are three kinds of woven carpets:
Velvet, Wilton and Axminster. Velvet is
the least complicated of construction
methods. Velvet carpets usually come in
one solid coloured and a tweed effect
may be noticed. Wilton carpets are more
intricate. These are manufactured by
using a Jacquard loom which can hold up
to six different coloured of yarns. The
Axminster method of weaving carpets
produces the most elaborate designs with
a wide variety of coloured.
• Knitted carpets are faster to make. In
knitting, several sets of needles create
loops and these are stitched together
before the backing is applied. Knitted
carpets come in solid or tweed and the
pile may be of the same size or of
varying heights.
• Flocked carpets are similar to Velvet
carpets in appearance. They have a dense
cut pile of short fibres that are
imbedded into an adhesive-coated
backing.
• Needle-punching is similar to
hand-hooking. Formerly used for
indoor-outdoor carpets, this process is
now being used for carpets that are only
meant to be placed indoors as well. In
needle-punching, fibres are locked into
a packing by using hooked needles, which
are further compressed.
The Manufacturing
Process
The process of manufacturing tufted
carpets can be explained in the
following steps:
Step 1: Preparing the yarn
• First, the synthetic yarns arrive at
the carpet manufacturer either in staple
fibre form or in bulk continuous
filament form
• The staple fibres, which are an
average of 7 inches (18 cm) long are
generally loose and are individual
strands that arrive in bales. Several
bales are blended together into one
batch in a hopper.
• Then, these strands are lubricated and
are spun into long, loose ropes called
slivers by a carding machine. The
slivers are then pulled, straightened,
and spun into single yarn that is wound
onto spools.
• Both the single-ply staple fibres (now
spun into filament) and the bulk
continuous filament is then twisted
together to form thicker two-ply yarn
suitable for tufting.
• The yarns are then steamed to bulk
them, and then heated to 270-280°F
(132-138°C). This heat setting causes
the yarn to maintain its shape by fixing
its twist. After cooling, these yarns
are wound onto tubes and transported to
the tufting machines.
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Step 2: Dyeing the yarn
• Generally, most carpets are dyed after
tufting yet sometimes the yarns are dyed
first. The methods include putting
500-1,000 pounds (227-455 kg) of fibre
into pressurized vats through which
treated dyes are circulated, or passing
the fibre continuously through the bath,
or passing skeins of yarn through the
vat of dye.
• The yarn can also be put on forms, and
the heated dyes can then be forced under
pressure from inside the forms to
coloured the yarn.
• Another method passes the yarn through
printing rollers, while yet another
involves knitting the yarn onto a form
that is then printed with dyes before
the yarn is unraveled. All yarn that has
been dyed is then steamed, washed, and
dried.
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Step3: Tufting the carpet
• At this stage, the yarn is put on a
creel (a bar with skewers) behind the
tufting machine and then fed into a
nylon tube that leads to the tufting
needle.
• The needle pierces the primary backing
and pushes the yarn down into a loop.
Photoelectric sensors control how deeply
the needles plunge into the backing, so
the height of the loops can be
controlled.
• A looper, or flat hook, seizes and
releases the loop of yarn while the
needle pulls back up; the backing is
shifted forward and the needle once more
pierces the backing further on.
• Inorder to make a cut pile, a looper
facing the opposite direction is fitted
with a knife that acts like a pair of
scissors, snipping the loop. This
process is carried out by several
hundred needles (up to 1,200 across the
12 foot [3.7 ml width), and several
hundred rows of stitches are carried out
per minute. Thus, one tufting machine
can produce several hundred square yards
of carpets per day.
Step 4: Dyeing the tufted carpet
• Solid coloured carpeting: For this
carpet of several standard roll lengths
is sewn together to make a continuous
roll, which is then fed into a vat. The
vat is filled with water, which is first
heated before dyes and chemicals are
mixed in. The mixture is then slowly
brought to a boil and cooked for four
hours approx.
• Another method of making solid
coloured carpet is to sew several rows
together to make one continuous roll,
which is then fed under rods that bleed
the coloured into the pile. After
dyeing, the carpet is then steamed to
fix the coloured, excess coloured is
washed off, and the carpet is dried and
put on a roll.
• Printed Carpets: Inorder to make
printed carpet of various designs, white
carpet passes under screens in which
holes in the desired pattern have been
cut. The desired coloured is squeezed
through the holes in the screen, and the
carpet is advanced 36 inches (91 cm) to
a different screen that applies a new
coloured in a different design through
the screen. Up to eight coloureds can be
applied with this method.
• Another method of dyeing printed
carpet is to pass it under embossed
cylinders that have raised portions in a
design that press colour into the
carpet. Each cylinder provides a
different design for a different
coloured. After dyeing, the printed
carpet is steamed, excess dyes are
washed off, and the carpet is then dried
and put onto rolls to go to the
finishing department.
Step 5: Finishing the carpet
• The ends of the dyed carpet are first
sewn together to form a continuous belt.
This belt is then rolled under a
dispenser that spreads a coating of
latex onto the bottom of the carpet.
At the same time, a strong secondary
backing is also coated with latex. Both
of these are then rolled onto a marriage
roller, which forms them into a sandwich
and seals them together. The carpet is
then placed in an oven to cure the
latex.
• The completed carpet is then steamed,
brushed, vacuumed, and run through a
machine that clips off any tufts that
rise above its uniform surface. The
carpet is then rolled into 120 foot (37
m) lengths that are then packaged in
strong plastic and shipped to either the
carpet manufacturer's inventory
warehouse or to a retail carpet store. |
