There are few important fiber properties which are considered for spinning.
1. Fiber length & uniformity.
2. Fiber strength & elongation.
3. Fiber fineness.
4. Fiber maturity.
5. Fiber cleanliness.
6. Fiber color.
7. Fiber stiffness.
8. Some chemical deposits.
Fiber Length and uniformity:
Fiber length is one of the most important characteristics for spinning.
Staple length: It is defined as the average length of spun able fiber. Fiber length required for yarn manufacturing is 15-50mm. with an increase in staple length yarn quality decreases.
Impact of fiber length on yarn production and quality:
Yarn strength: short staple fibers reduces yarn strength.
Productivity: long staple fibers increase production and quality. Higher amount of short staple fibers will influence fiber end breakage, increases the quality of waste, increases the quality and production.
Yarn Hairiness: short staple fibers will leads to yarn hairiness.
Yarn evenness: shorter stable fibers will leads to yarn unevenness.
Spinning limit.
Productivity.
Handle of the product.
Luster of the product.
Fiber strength:
Fiber strength is one of the most dominating characteristics. Fiber shows a maximum strength of 60 CN/Tex (approximately).
Very weak fibers are not preferred as it will rupture during Blow room and carding, due to this short staple fibers are created (due to rupture fiber breaks), yarn strength decreases, and influences on uniformity.
In case of natural fibers like cotton, linen, etc. fiber strength increases with increase in moisture content. This phenomenon will be reverse in case of some manmade fibers like nylon, viscose, etc.
Fiber elongation:
1-2% elongation and more is preferred for spinning.
Fiber must be able to deform in order to withstand high load but it should also have to retain its original shape.
Higher elongation is not preferred as it makes difficulty to process in some operations like Drawing operations.
Fiber Fineness:
Fiber fineness will determine the number of fibers present in the cress section of yarn.
Minimum 30 fibers are needed at the yarn X-section, but now a days the minimum value of fibers per X-section is 100.
Fiber fineness will influence on:
Spinning Limit.
Luster.
Yarn evenness.
Handle.
Yarn fullness.
Productivity.
Fiber Maturity:
Generally maturity is considered for Cotton fiber, cotton fiber consist of cell wall and lumen. Fiber is to be considered as ripe when the cell wall of the moisture swollen fiber represents 50-80% of the round X-section as unripe when it represents 30-45 % & as dead when it represents less than 25%.
Immature fibers will influence on:
Loss of yarn strength.
Nepping.
A high number of short fibers.
Difference in dye ability.
Process difficulty in carding etc.
Fiber cleanliness:
Trash present in the fibers especially metal parts will cut the fibers and also harmful to spinning machine.
Trash will make disturbance in drafting.
Trash content will jam in carding pin.
Mineral content will decay the rolling parts of the machine.
Fiber Color:
Fiber color is one of the important parameters need to be considered for Spinning process because fiber color will tell about how well a fabric or yarn will bleach or dye.
Fiber Stiffness:
Fiber stiffness will play an important role in rolling, revolving, and twisting movements. A stiff fiber cannot properly bond into the yarn, which will ultimately result in hairiness.
Fibers with low stiffness cannot maintain its shape after deformation, which ultimately results in the formation of neps.
Chemical Deposit:
Chemical deposits are nothing but the substances present on the surface of the fiber. Some of the chemical deposits are:
Honey Dew (Sticky substance)
Sugar.
Wax.
Oil.
Fat and some other synthetic substances.
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