Produção de Tecidos de Terry com Padrões Exclusivos

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� Do you know how manytimes a day you use terry
fabrics? Every morning in the
bathroom, almost every time you
wash your hands, in leisure activi-
ties and sports, and even for rela-
xation. Some 2.5 billion square
metres of terry are produced in the
world every year – not much less
than the surface area of the Grand
Duchy of Luxembourg. 
We distinguish two qualities of ter-
ry, according to the loop structure:
• Classic terry, with upright loops
(made of twisted yarn). These
terries are usually patterned
with dyed yarns. 
• Fashion terry, also known as
milled or fulled goods, with spi-
ral loops (of single yarns). These
are mainly piece-dyed or printed
fabrics. 
A blend of single and twisted yarns
produces additional pattern ef-
fects.
LOOP FORMATION
TECHNOLOGY
In the production of terry fabrics
two warps are processed simulta-
neously: the ground warp, with
tautly tensioned ends, and the pile
warp, with lightly tensioned ends.
A special weaving method enables
loops to be formed with the lightly
tensioned warp ends on the fabric
surface. With the basic method,
known as three-pick terry (Fig. 1�),
three picks form a pick group. By
means of a special device on the
weaving machine, two picks are
inserted at a variable distance –
the loose pick distance – from the
cloth fell. The loose pick distance is
varied according to the desired
6 S U L Z E R T E C H N I C A L R E V I E W 2 / 9 8
Terry Fabrics with
Exclusive Patterns
3769
RUDOLF VOGEL
SULZER RUTI
Articles made of terry fabric are used daily in many areas.
They have loops at least on one side, and usually on both sides.
The production of terry fabric is a complex process and is only
possible on specially equipped weaving machines. Now, with
an ingenious new technology, terry fabrics with exclusive
patterns can be produced on high-speed weaving machines. 
1� Structure and origin of a 3-pick terry fabric.
1
1
2
1
Loose pick distance
3-pick group
Reed
1st loose pick
2nd loose pick
Beat-up pick
Pile warp yarns Ground warp yarns2
Fabric
loop height. When the third pick is
beaten up, the reed pushes the pick
group on the tautly tensioned
ground warps towards the fell, and
the loose pile warp ends woven into
the pick group are uprighted and
form loops. Depending on the
weave, loops are thus created on
one or both sides of the fabric. 
PATTERNS TO CHOICE
For complex patterns, the weaving
machine has to be equipped with 
a jacquard machine. For less
demanding patterns, a dobby is
sufficient, and very simple, non-
patterned fabrics can be woven
with a tappet motion. Terry fabrics
are often very complex, with differ-
ent-coloured warp ends in combi-
nation with loop patterns.
NEW DIMENSIONS 
IN PATTERNS
Terry fabrics are subject to chang-
ing fashions: the market is con-
stantly demanding new qualities
and designs. The rapid develop-
ment of electronics, with micro-
processor controls and highly
dynamic stepping motors in combi-
nation with modern mechanisms,
has enabled fabric designers to
produce completely new patterns.
One such mechanism is the special
terry sley gear with dynamic pile
control, as used by Sulzer Ruti in
the terry version of the G6200 rapi-
er weaving machine (Fig. 2�). Via a
servo motor, the beat-up position
for each pick and thus the type of
terry and the pile height can be
freely programmed from one pick
group to another. In this way, 200
different loose pick distances and
hence the same number of pile
heights can be programmed in any
order desired. For example, 3- and
4-pick terry, and even fancy types
of terry can be combined in the
same length of fabric. This gives
the fabric designer a broad range
of patterning options, and the
3� Diagram of a
7-weft terry
machine with 
2 pick groups and
full beat-up.
S U L Z E R T E C H N I C A L R E V I E W 2 / 9 8 7
76543217654321
2� The terry sley gear with highly dynamic drive offers
new scope for pattern design.
5� The G6200
rapier weaving
machine, equipped
with a jacquard
machine and a
control system for
eight weft colours,
combines exclusive
pattern technology
with high perfor-
mance and excellent
fabric quality. 
pattern formation lies in the fact
that two loose pick groups formed
at distances corresponding to the
pile heights are beaten up to the
cloth fell together.
For two short loops, the pile
threads are woven into both loose
pick groups and for one large loop
into the second loose pick group
only. The greatest difficulty was 
to develop a basic weave which
results in neat loops without exces-
sive friction between warp and
weft at full beat-up. The solution
was found in a special 7-pick weave
combined with full beat-up at the
6th and 7th pick (Fig. 3�). In this
way, a second pile height is also
formed in weft direction, making
sculptured patterning possible by
the difference in pile height in
warp and weft direction (Fig. 4�).
THE G6200 RAPIER 
WEAVING MACHINE
A precondition for this kind of pat-
tern formation is freely program-
mable sley travel, as on the Sulzer
Ruti G6200 rapier weaving ma-
chine. Microprocessor control
allows the loose pick distance to be
programmed easily and individu-
ally for each pick. Adaptations can
be carried out at any time, for
instance when a pattern is woven
for the first time. The terry version
of the G6200 rapier weaving
machine (Fig. 5�) can be equipped
with a control system for a maxi-
mum of eight different weft colours
or yarns, and a jacquard machine,
thus giving fabric designers prac-
tically unlimited scope for the
design of terry fabrics. Ω
8 S U L Z E R T E C H N I C A L R E V I E W 2 / 9 8
4� Terry fabrics with two pile heights in warp
and weft direction on the weaving machine. The
two loose pick groups can be seen in front of the
fell. 
1st pick group 2nd pick group Low pile height High pile height
weaving engineer a technology for
improving the fabric structure,
because the transition from one
pattern element to the next can be
woven with greater precision.
With these elements, Sulzer Ruti
specialists have now developed a
new patterning method referred to
as sculptured terry. At each full
beat-up, two pile loops of different
heights are formed in weft direc-
tion. The secret of this method of
F O R M O R E D E T A I L S
Sulzer Ruti Ltd.
René König, 9018
CH-9630 Ruti 
Switzerland
Telephone +41 (0)55-250 24 65
Fax +41 (0)55-250 21 71
E-mail rene.koenig@sulzer.ch
S U L Z E R T E C H N I C A L R E V I E W 2 / 9 8 9
WEAVING BASICS
A plain-weave fabric 
structure.
Weaving process (schematic).
Longitudinal section
Cross-section
Fabrics are produced by crossing threads at right-
angles to one another. By using different-coloured
threads and by the method used to cross them, pat-
terns are produced. The way the threads are crossed
is referred to as a weave. In the case of the simplest
fabrics, the threads are crossed one-to-one. The
result is a plain weave (picture left). The longitudi-
nal threads are the warp; those running in trans-
verse direction are the weft.
By separating the warp threads a “shed” is formed.
The weft is inserted into this shed and beaten up to
the fell – the edge of the fabric – by the reed. Each
warp thread is inserted into the thread eyelet of a
heald; the healds are arranged on the heald shafts.
The shed is created by raising some of the shafts
and lowering the rest (picture right). 
When weaving simple fabrics, the shafts are moved
by lifting mechanisms (cams). For sophisticated
fabrics programmable tappet motions are needed.
Jacquard machines offer almost unlimited scope,
enabling up to 12,000 weft threads to be controlled
individually. Even pictures can be woven. Modern
tappet motions and jacquard machines are elec-
tronically controlled. 
Originally, the weft was inserted by transporting
(throwing) a small bobbin of yarn back and forth
through the shed in a shuttle. In modern high-speed
weaving machines, which have no shuttle, the weft
is inserted into the shed from fixed bobbins by pro-
jectiles, compressed air or rapiers.The total num-
ber of weaving machines producing fabrics world-
wide is about 5 million. Shuttleless weaving ma-
chines account for between 25% and 30% of this
total.
Warp beam 
Warp threads
Shaft
Healds
Reed
Weft threads
Fabric
Cloth beam
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5
6
7
8
1
2
3
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6 7
8
1
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1
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