Systems of grading of wool Blood system Numerical System

1. Grading & judging of wool

2. Introduction
•Grading: Grading refers to the average diameter or
thickness of the fibers. It also means the placing of entire
fleeces in their grade piles according to fineness and
length.

3. Benefits:
• The potential range of end products that wool may be used for is dictated by
many qualities, including fineness, clean wool yield, length, color, and
uniformity.
• Fineness, or grade, is of primary importance in determining market value of
raw wool.
• Reliable information on the grades and quality of wool helps ranchers
calculate the true value of these products.
• They also are better able to plan and execute breeding programs through
which they can produce the most popular and profitable types of wool.

4. Systems of grading of wool
There are two systems of wool grading.
• American system or blood system.
• British system or numerical system/spinning count system.

5. BLOOD SYSTEM
• This system is of American origin and it is chiefly used in USA.
• This is based on fineness of wool. Fleeces of the same diameter shorn from
full blooded Merino called ‘’Fine’’.
• The other grades are as follows:
• Half-blood, 3/8 blood, ¼ blood. These are described on relative fineness of
the wool obtained from sheep containing fractional amounts of Merino
blood.
• Lower quarter blood, commons and braid are the wool of descending order
in quality from quarter (1/4) blood wool.

6. NUMERICAL SYSTEM
• It consists of finest count to which it can be spun. This is used in most
countries of the world.
• This system is based on number of yarn or hanks that can be made from one
pound of scoured or combed wool.
• If fineness of fibre is more the length of yarn is greater. A hank is equal to
512 m in length.
• A grade of 60’s would mean that 60 hanks could be made from 1 pound and
it would be superior/finer to wool of 50’s.
• Similarly, a grade of 50’s would be finer than a 40’s wool. In case of 40’s
wool, the number of hanks is 40 and so on.

7. Comparison of both systems

9. PARAMETERS OF JUDGING WOOL QUALITY
• Diameter/thickness: The fineness of wool depends upon its
diameter. It varies from 0.008 to 0.002 inch (0.2 to 0.05 mm).

10. • Staple length: It is total length of a fibre in its natural condition. It is obtained
by measuring the natural staple without stretching the crimps out of the
fibre.
• Fiber length: It is the total length of the fibre after removing the crimps or
waviness by straightening staple wool.
• Elasticity: The property of wool fibres to return to their original or natural
form after being stretched or compressed. Wool is quite elastic and
therefore resist wrinkling, bagging and tearing

11. • Kemp: It is chalky, white lustreless and dead fibre growing with wool which
resist dye stuff. It is a reject wool fibre.
• Heterotype: Fibres which occur in the fleeces of indiscriminately bred sheep.
They show, at different parts of their length, the physical structure and
characteristics of both wool and hair.
• Lustre: It is ability of wool to reflect light. Wool with lustre when dyed has
brighter appearance than wool without lustre. Coarse wool with fewer
scales has more lustre than fine wool because of smoothness of fibre. The
brilliant, glossy appearance of wool is associated with English long wools.

12. • Crimpiness: It is waviness of the wool fibre. Its number varies
from 2 to 12 per cm depending upon qualities as follows:

13. It is valuable property in spinning and increase elasticity of the yarn and fabric.
An uneven growth of elongated cells in the cortex (middle part of the fibre)
causes fibre to contract and bend which gives a wavy appearance. In fine wool
crimps are very pronounced.
• Strength of wool: It signifies the property of wool fibre to undergo
processing without breaking. Wool fibre and fabrics are usually strong and
durable. It is necessary for textile material.
• Conductivity: Wool is best of fibres for holding in body heat and also keeping
heat out. This is due to insulating value and to open porous nature of fabric
made from it.

14. • Dyeing properties: Wool is one of the fibres easiest to dye, because dyes
penetrates-easily into the fibre and it is permanent.
• Softness: Soft wool produces fabrics softer to touch. In a soft, pliable fibre
the scales are numerous and fit one over the another loosely.
• Inflammability: Wool is slower to burn and on burned it gives off a pungent
odour and forms a bead where burning ceases.
• Action of chemicals: Dilute acid do not act upon wool. The affinity which
exist between wool and dilute acid is utilized in dyeing with acid colours.
Alkalies weaken the wool and may even completely dissolve it.

15. • Action of heat: Wool is poor conductor od heat, and for this reason it is very
desirable where warmth is desired.
• Moisture: Wool readily absorbs and gives off moisture. Under normal
conditions the moisture content varies from 12 to 17%. When placed on
damp cloth may even absorb more moisture even up to 30%.
• Bulkiness: It generally indicates a high yield of clean wool. Squeezing the
fleece together with the hands may help you estimate clean wool. If you are
able to compress the fleece so that your hands close together, the yield of
clean wool will be low.

16. Conclusion
The importance of grading and judging within a given lot or fleece of
wool depend upon various factors. A producer with a good knowledge of
wool encounters fewer problems in production and marketing. Reliable
information on the grades and quality of wool helps ranchers calculate
the true value of these products. They also are better able to plan and
execute breeding programs through which they can produce the most
popular and profitable types of wool.

17. References
• JAGDISH PARKASH. Goat, sheep & pig Production and management. p.
254.
• https://sites.google.com/site/viveklpm/wool/wool-quality-assessment