Wool Sorting Process
Md. Abu Sayed
Pabna Textile engineering college, Pabna, Bangladesh
As it comes from the sheep’s back, wool is not a very promising fiber in appearance. Even though the sheep have been washed shortly before shearing, dirt and leaves, grasses and thorns, cling closely to the matted and tangled tresses of the fleece. Dead hairs, or kemps as they are named, mingle with the healthy wool; different parts of the fleece vary in length and quality of fiber. Yet from the dirty and tangled mass of mixed fibers fine threads are drawn and fabrics woven.
Uses of wool:
- The great mass of wool is used in the manufacture of woolen and worsted cloths.
- Used for the pile of all classes of carpets, for felts and knitted fabrics.
- Blankets, flannels, baizes and other special fabrics use up a considerable quantity of fiber.
What is sorting of wool?
Sorting is the process of separating different qualities of wool. Closely examined, the fleece of the common sheep shows thirteen or fourteen different qualities of wool. The best quality of wool is obtained from the shoulders and back of the sheep and the poorest wool is obtained from the lower legs. Fineness, color, crimp, strength, length and elasticity are the characteristics that may vary with the breed of sheep. As a rule, one quality of wool is found in the same part of every fleece taken from the same species of sheep.
To obtain a uniform quality of wool, therefore, we take the same section out of any number of fleeces. In other words, we sort out each fleece into as many divisions as there are qualities of wool. It is evident that, only a small quantity of each quality can be obtained from a single fleece, and that we require a great number of fleeces for a given ‘make’ of yarn or cloth. This, however, is of little consequence in a factory where thousands of fleeces are consumed weekly, and the division of the fleeces gives to the manufacture a uniform quality of fiber for either high or low classes of work.
Woolen and worsted sorting terms:
The two treads had each its own method of sorting the fleece and its own sorting terms. Woolen sorters divided the fleece up in this fashion:
- Picklock (Fore shoulder) – Choicest in fineness of fiber, elasticity and strength of staple.
- Prime (Middle of body) – Slightly inferior in strength, but otherwise as good.
- Choice (Back) – True, but not as fine as prime.
- Super (Lion) – Not so valuable as choice, but similar in general properties.
- Head – Inferior sorts of wool derived from that part of the sheep,
- Drawn right (Lower sides) – Showing tenderness, but fair quality of wool.
- Seconds (Throat and breast) – Best of the wool from these parts.
- Breech – Short, coarse hair from the hinder parts.
The worsted selection puts a premium on fineness, as the following classification shows:
- Blue – From the neck.
- Fine – From the shoulders.
- Neat – From the middle of the sides and back.
- Brown-drawing – From the haunches.
- Breech or britch – From the tail and hind legs.
- Cow-tail – When the wool behind the legs is very strong.
- Brokes – From the belly and lower parts of the front legs, classed as super, middle and common, according to quality.
Woolen sorting gives nine classes and worsted sorting ten grades of wool from one fleece. Scientific sorting theory makes a closer grading for both industries; but the practical sorter seldom acts up to theory, his sorting numbers usually falling short of even the nine obtained by the woolen masters of an older day.
English wool sorting:
For those manufacturers who desire to grade their wools finely the fleece of the common sheep has been carefully mapped out as follows, the lowest numbers denoting the highest qualities –
- Shoulder: Long and fine wool, growing close and even.
- Side: Stronger, but otherwise equally good.
- Neck: Short, but fine, liable to be mixed with grayish wool near the head.
- Back of neck: Inferior to first three.
- Top of fore shoulder: Faulty and irregular, but of fair medium quality.
- Lions and back: Rather coarse and short, but fairly true in character.
- Middle of haunch: Long, strong wool of large staple, grading from fine to coarse.
- Hinder parts: Coarse and long, apt to be hairy.
- Top of hind legs: Very like 7, but rather dirtier.
- Under body: Short, dirty, but fine towards the fore legs. A tender wool, and known as ‘brokes”.
- Top of fore legs: Short and fine.
- Throat: Irregular, short, and kempy; very often full of grass and fodder.
- Head: Short, rough and coarse wool.
- Shanks: Rough, hard wool; very short and of little value.
Sorting the Merino fleece:
The merino sheep produces the finest of all wools, and the fleece has been finely graded by Dr. Bowman in this manner –
- Shoulders: The wools grown on these parts are commonly the best in the fleece, being specially strong and long in staple, soft in texture and uniform in character.
- Sides: Same as shoulders.
- Lower part of back: This is also wool of good, sound quality, resembling in staple that obtained from the shoulders and sides, but not so soft and fine in fiber.
- Loin and back: The staple here is comparatively shorter and the hair not so fine, but the wool on the whole is of a true character. In some cases, however, it is rather tender.
- Upper parts of legs: Wool from these parts is of a moderate length but coarse in fiber, and is disposed to hang in loose, open locks. It is generally sound, but liable to contain some vegetable matter.
- Upper portion of neck: The staple of the wool clipped from this part of the neck is wholly of an inferior quality, being faulty and irregular in growth, as well as full of thorns, twigs, grass, and other matters.
- Central part of back: This wool closely resembles that obtained from the loins and back, and is rather tender.
- Belly: This is the wool grown on the under parts of the sheep, between the fore and hind legs. It is short, dirty and poor in quality, and somewhat tender.
- Root of tail: Fiber coarse, short and glossy, and very often the wool is mixed with kemps or dead hairs.
- Lower parts of legs: Most of the wool grown on these parts is dirty, greasy, and rough, the staple lacking curliness and the fiber fineness. It is usually full of burrs and vegetable matters.
- Head: The wools from the part is stiff, straight, coarse, mixed with fodder and kempy.
- Throat: Same as head.
- Chest: Same as head.
- Shins: The wool from the shins is short, straight and stiff and of small textile value.
Spanish wool shorting:
The merino fleece is generally divided by the Spaniards into four parcels, viz –
- Refina: Extending from the lower jaw down to the fore fore shoulder, across to the haunch, curving round to the back above the tail.
- Fina: Taken from the belly, hind quarters, and upper thighs.
- Tercina: Short wool taken from the head, throat, lower part of the neck and shoulders, ending at the joint.
- Inferior: From forehead, cheeks, tail, and legs.
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Founder & Editor of Textile Learner. He is a Textile Consultant, Blogger & Entrepreneur. He is working as a textile consultant in several local and international companies. He is also a contributor of Wikipedia.