STEPS INVOLVED PROCESSING OF WOOL

1. T.NANDINI DEVI
MVM 15025

3. The major steps necessary to process wool
from the sheep to the fabric are:
 shearing,
 cleaning and scouring,
 grading and sorting,
 carding,
 spinning,
 weaving, and
 finishing.

5. Shearing
 Sheep are sheared once a year.
 The fleece recovered from a sheep can weigh between
6 and 18 pounds (2.7 and 8.1 kilograms).
 While most sheep are still sheared by hand, new
technologies have been developed that use computers
and sensitive, robot-controlled arms to do the clipping.

7.  Australian scientists created a chemical method of
shearing called "bio-clip."
 Injected with recombinant epidermal growth
factor (EGF), that causes the wool follicle to break
and the fleece to drop off on its own.
 This causes natural disruption of hair growth,
allowing the wool to be slid, glove like, from the
sheep 4 weeks after the injection.

9.  Scientists have developed a shearing table so
the shearer doesn't have to hold the sheep.
They have also developed a "robot" for
shearing.

10. Cleaning and scouring
 Wool taken directly from the sheep is called "raw" or
"grease wool."
 It contains sand, dirt, grease, and dried sweat (called
suint).
 Weight of contaminants 30 to 70 percent of the
fleece's total weight.
 To remove these contaminants, the wool is scoured in a
series of alkaline baths containing water, soap, and
soda ash or a similar alkali.

11.  Scouring is washing the wool in hot soapy water to
remove dirt, grease and dry plant matter from the
fleece.
 The preferred water temperature for washing wool
is 140⁰F.
 Use a mild soap.
 Commercial processors may use a slight alkaline
solution (by adding sodium carbonate) to aid in the
scouring process.

12.  The key is to keep the water temperature and the
volume of soap used as low as possible while still
being able to wash out the grease and dirt.
 Wool that is very greasy will require hotter and
stronger solutions to remove the grease.
 In the scouring process the wool undergoes several
soaks and rinses until the wash water remains
clean.
 Let wool soak and avoid agitation.

13.  Between each wash the wool is pressed or
squeezed to remove excess water.
 When washing wool, consideration must be given
to the quality of the water.

14. Skirting a fleece:
 The wool from the back end of the sheep, their
legs and sometimes their belly is too full of
manure to use. These are referred to as "tags”
 These are removed first before washing the fleece;
this process is called skirting

16.  Lanolin, a kind of grease, is the by-product of this
process and it is purified for use in the manufacture of
cosmetics, soap and other household products.
 used as a moisturizer to treat or prevent dry, rough,
scaly, itchy skin and minor skin irritations.
 Lanolin oil is used as a stabilizer, as an emulsifier in
ointments, and in medications such as zinc oxide.
 Lanolin oil benefits industries as an anticorrosive or a
lubricant and is often used in the leather industry.

18. Grading and sorting
 Grading is the breaking up of the fleece based on
overall quality.
 In sorting, the wool is broken up into sections of
different quality fibers, from different parts of the
body.
 The best quality of wool comes from the shoulders
and sides of the sheep and is used for clothing; the
lesser quality comes from the lower legs and is
used to make rugs.

20. Wool Grading by the American Blood
Count System:
Fine Wool 2 1/2 inches in staple length
Very fine crimp (close
together)
1/2 Blood Wool 3 inches in staple length Medium fine crimp
3/8ths Blood Wool 3 1/2 inches in staple length Medium crimp
1/4 Blood Wool 4 inches in staple length Medium coarse crimp
Low 1/4 Wool 4 1/2 inches in staple length Coarse crimp (large waves)
Common 5 inches in staple length Very coarse
Braid 6 inches in staple length The most coarse

21. SPINNING COUNT:
 It is defined as the number of hanks of yarn
that can be spun from a pound of wool.
 A hank of wool is 560 yards long (560 yd/lb =
1.129 km/kg).

22.  "A hank of wool is a length of wool pulled into
a coiled form. A hank of wool is used in heavier
textiles and for some furniture.”
 A hank of linen is 300 yards or approx 270 metres
 A hank of cotton or silk is 840 yards or approx
768 metres.
 1 hank = 20 feet = 6.096 metres

24. American
Blood Grade
Spinning
Count
Range for Average
Fiber Diameter (µm)
Maximum
Standard
Deviation
Fine Finer than 80s
80s
70s
64s
under 17.70
17.70-19.14
9.15-20.59
20.60-22.04
3059
4.09
4.59
5.19
1/2 Blood 62s
60s
22.05-23.49
23.50-24.94
5.89
6.49
3/8 Blood 58s
56s
24.95-26.39
26.40-27.84
7.09
7.59
1/4 Blood 54s
50s
27.85-29.29
29.30-30.99
8.19
8.69
Low 1/4 Blood 48s
46s
31.00-32.69
32.70-34.39
9.09
9.59
Common 44s
40s
34.40-36.19
36.20-38.09
10.09
10.69
Braid 36s
Coarser than 36s
38.10-40.20
more than 40.20
11.19

26. The English (Bradford) Spinning Count System
or MICRON SYSTEM:
 This originated in the 19th century (along with
mechanized spinning equipment).
 It is the number of hanks of yarn, each 560 yards in
length, that it is possible to spin from one pound of
clean wool.
 Finer the wool fiber, the more hanks (greater length,
thinner yarn) that can be obtained from one pound.
 For this you need a microscope and a background slide
with micron crosshairs for comparison

27. Fine Wool 64 to 70 to 80 Hanks Less than 22.04 Microns
1/2 Blood 60 to 62 Hanks 22.05 to 24.94 Microns
3/8 Blood 56 to 58 Hanks 24.95 to 27.84 Microns
1/4 Blood 50 to 54 Hanks 27.85 to 30.99 Microns
Low 1/4 46 to 48 Hanks 31.00 to 34.39 Microns
Common 44 to 40 Hanks 34.40 to 36.19 Microns
Braid 40 to 36 Hanks 36.20 to 40.20 Microns

28. Delaine Merino 18 to 22 Microns
Rambouillet 19 to 25 Microns
New Zealand Merino 20 to 25 Microns
Targhee & Romeldale 22 to 26 Microns
Corriedale & Columbia 22 to 34 Microns
Southdown 24 to 31 Microns
Blue Leicester 24 to 28 Microns
Shropshire, Suffolk, Dorset Horn,
Montadale
25 to 31 Microns
Finish Landrace (Finns) & Cheviot 25 to 32 Microns
Oxford 29 to 34 Microns
Romney 31 to 36 Microns
Border Leicester 33 to 38 Microns
Lincoln & Cotswold 37 to 40 Microns

29. Breed Range of
Average Fiber
Diameter (µm)
Range of
Grease Fleece
Weight (lb)
Range of Clean
Wool Yield (%)
Border Leicester 38-30 8-12 60-70
Cheviot 33-27 5-8 50-65
Columbia 30-23 9-14 45-60
Cormo 22-19 10-14 60-70
Corriedale 31-24 9-14 45-60
Debouillet 23-18 9-14 45-55
Delaine-Merino 22-17 9-14 40-50
Dorset 32-26 5-8 50-65
Finnsheep 31-24 4-8 50-70

30. Hampshire 33-25 6-10 50-60
Lincoln 41-34 10-14 55-70
Merino (superfine) <18 6-9 60-70
Merino (fine) 19-20 6-11 60-70
Merino (medium) 21-22 9-13 65-75
Merino (strong) 23-26 11-15 65-75
Montadale 30-25 7-11 50-60
Oxford 34-28 7-10 50-60
Rambouillet 23-19 9-14 45-60
Romney 39-32 8-12 55-70
Shropshire 33-25 6-10 50-60
Southdown 29-24 5-8 40-55
Suffolk 33-26 4-8 50-60
Targhee 25-21 9-14 45-60
Texel 33-28 7-10 60-70
*Primary source: Sheep Production Handbook. 1996. American Sheep Industry Association Inc. Production,
Education, and Research Council.

31.  The clean wool now to be further processed before
being spun into woollen or worsted yarn.
 Woollen yarn  more bulky, hairy and irregular
than worsted yarn and today is used for items such
as carpets or knitwear.
 Worsted yarn  more tightly spun, smoother
looking than woollen yarn and stronger

32. Woolens Worsted
Spun from short wool fibers
(1-3 inches long)
Spun from long wool fibers
(more than 3")
Spun from medium or coarse
diameter wool fibers
Spun from fine diameter wool
fibers
Fibers are washed, scoured and
carded
Fibers are washed, scoured,
carded, combed and drawn
lower tensile strength than
worsteds
higher tensile strength than
woolens
low to medium twist tighter twist
Bulky, uneven yarn Fine, smooth yarn
Soft, fuzzy appearance crisp, smooth appearance
heavier weight lighter weight
not as durable as worsteds More durable than woolens
does not hold crease well holds crease well

33. Woolen Processing Worsted Processing
Spun from wool fibres of:
Length : spun from short fibres of 1-3”
Diameter: medium or coarse
The fibres are washed, scoured and carded.
Spun from wool fibres of:
Length : longer than 3”
Diameter: fine diameter
Fibres are washed, scoured, carded,
combed and drawn
Yarn
Bulky
Uneven
Low to medium slack twist
Tensile strength lower than worsted
Yarn
Fine
Smooth and Even
Tighter twist
Higher tensile strength
Fabric Appearance
Soft, Fuzzy, Heavier weight
Fabric Appearance
Crisp, Smooth,Lighter weight
Characteristics
Insulator due to trapped air
Does not hold a crease well
Less durable than worsted
Characteristics
Less insulator
Holds creases and shape
More durable than woollens
Uses
Sweater,Carpets,Tweeds
Uses
Suits, Dresses, Gabardines,Crepes

36. Carding
 The fibers are passed through a series of metal teeth
that straighten and blend them into slivers.
 Carding also removes residual dirt and other matter left
in the fibers.
 Carded wool intended for worsted yarn is put through
combing, a procedure that remove short fibers and
place the longer fibers parallel to each other.
 Carded wool to be used for woolen yarn is sent directly
for spinning.

39. Combing
 Combing takes out the shorter fibres, also called
noils, and lines the longer fibres up parallel with
one another in a 'sliver‘ [A sliver is a long bundle
of fiber that is generally used to spin yarn].

42. Spinning
 The craft of spinning is thousands of years old.
 During the spinning process the fibres are twisted into
a long, continuous thread, or yarn. This used to be done
with ‘spindle whorls’
 The invention of the spinning wheel greatly increased
the speed at which yarn could be spun.
 Today, spinning can be done on a variety of machines,
depending on whether the yarn is destined to become
woollen or worsted cloth.

44. Weaving
 The wool yarn is woven into fabric.
 Wool manufacturers use two basic weaves: the
plain weave and the twill.
 Woolen yarns are made into fabric using a plain
weave (rarely a twill), which produces a fabric of a
somewhat looser weave and a soft surface (due to
napping) with little or no luster.

46.  Worsted yarns can create fine fabrics with
exquisite patterns using a twill weave.
 The result is a more tightly woven, smooth fabric.
 Better constructed, worsteds are more durable than
woolens and therefore more costly.

47. Finishing
 After weaving, both worsteds and woolens
undergo a series of finishing procedures including:
• Fulling (immersing the fabric in water to make the
fibers interlock); and stretching.
• crabbing (permanently setting the interlock) and
decatsing (shrink-proofing);
• occasionally, dyeing.

50. Fulling
 Use of heat, moisture and extreme agitation to
make a wool fabric shrink and therefore become
stronger and warmer
 Fulling can reduce the size of a piece of cloth by
up to a third.
 The cloth was then treated by being beaten with
large hammers called ‘stocks’.

51. Stretching
 Fulling processes are followed by stretching the
cloth on great frames known as tenters, to which it
is attached by tenterhooks.
 The area where the tenters were erected was
known as a tenterground.

52. Crabbing:
 The process ensures that the fabric is stretched
or loosened as necessary and evens out the thickness of
the fabric.
 Crabbing prevents the formation of creases or uneven
shrinkage.

53. DYEING:
 As wool readily accepts dye colors, dyeing can
occur at almost any stage of the wool processing.
 The two common stages for wool dyeing is right
after washing or after spinning wool into skeins of
yarn.
 If the dyeing occurs after the wool is washed then
it is referred to as stock dyed wool.
 If the wool is dyed after it is spun into yarn then it
is referred to as yarn dyed.