**Some Useful Formulas for Determining Fiber Properties**

**Amit Kumar Das**

Founder of "টেক্সটাইল ম্যানিয়া" Blog

Pabna Textile engineering college, Pabna, Bangladesh

**Cell:**01770 456240

**Email:**amitptec6th@gmail.com

**Introduction:**

Today we will discuss about some easy formula aims to determine some important

**properties of fiber**like diameter of fiber, fiber maturity, spinning limit, spinning value of

**cotton fiber**, standard fiber fineness etc. Those properties are necessary to know before taking decision about production. So lets have a look how can we determine those?

**Diameter of Fiber:**

**(I) Diameter of fibre in microns**= 2000 = √ { X ÷ ( Y x π x 9000 ) }

Where,

X = Fibre denier

Y = Fibre specific gravity

Denier is the mass in grams of 9 kilometres of the material.

Also ,

1 denier = 0.05315 grains and

Denier = 5315

*÷*cotton count

**(II) Fiber diameter in microns**= 20 √ { Denier ÷ (3.14 x specific gravity)}

**Fibers per cross section of yarn (T),**

T = 20√ [ { 53.15 x sum of ( % of each denier ÷ each denier) } ÷ ( yarn count to be spun ) ]

**Fiber maturity:**

**Fibre maturity ratio**= (Normal – Dead ) /200 + 0.7

**Maturity coefficient**= ( N + 0.75T + 0.4 D) / 100

Where,

N = normal coefficient

T = Thin walled of half mature fibers

**Spinning limit:**

**Spinning limit**= 5315 / (Denier of fibre x Actual fibres per cross section)

The ratio should be about 3200 for fine

**yarn counts**and about 3000 for course counts.

**Neps:**

**Neps per 100 square**= { (1.531 – log (34-x)) x 100 } / 0.434 inches of web

Where X is the number of cells containing neps (Shirley template method) and 34 is the total number of cells.

**Spinning value of cotton:**

The formula given by Indian Central Cotton

**C**ommittee is

C = 78.2X

_{2 }- 79.2X_{3 }- 24.8Where ,

C = highest standard warp count.

X

_{2}=Mean fibre length In inches

X

_{3}= Mean fibre weight per inch (106 oz. )

**Another formula to predict spinning value from fibre properties is:**

X

_{1}

_{}= 71.6X

_{2}- 70.8X

_{3}– 20.8X

_{4}+ 17.9X

_{5}+ 0.037X

_{6}+ 4.4 X

_{7}

^{-14.1}

X

_{1}= Highest standard warp count

X

_{2}= Fibre length (inches)

X

_{3}= Fibre weight per inch (10-6 oz.)

X

_{4}= Fibre width(10-3 inch)

X

_{5}= Fibre strength

X

_{6}= Fibre convolutions

And X

_{7}= Fibre rigidity (oz./inch2 x 10-6)

**Standard fiber fineness :**

Standard fiber fineness = Measured fineness / Maturity ratio