Textile Institute of Pakistan - Yarn Count Systems

Questions and Answers

What does yarn count indicate about the yarn?

The tensile strength of the yarn

The degree of fineness or coarseness of yarn (correct)

The color of the yarn

The length of the yarn

In a direct yarn numbering system, what is fixed while measuring the yarn count?

Weight per unit length (correct)

Type of fiber

Both width and length

Length per unit weight

Which formula is used to calculate count in the direct yarn numbering system?

N = W / L

N = S x (W / L) (correct)

N = L / (W x S)

N = W + L - S

What does a higher count value indicate about the yarn?

The yarn is coarser Signup and view all the answers

Which of the following is NOT a type of direct yarn numbering system?

Deci Signup and view all the answers

How is Tex defined in terms of yarn measurement?

Weight of yarn in grams present in 1000 meters length Signup and view all the answers

Which yarn numbering system is characterized as a universal system?

Tex Signup and view all the answers

What does the term 'indirect system' refer to in yarn numbering?

Length is fixed while weight varies Signup and view all the answers

What is the formula for calculating denier?

Denier = 9000 x (Weight in grams / Length in metres) Signup and view all the answers

What does the term 'grist' refer to in textile measurement?

Weight in pounds of 14400 yards of yarn Signup and view all the answers

How is silk count calculated?

Silk Count = 1000 x (Weight in drams / Length in yards) Signup and view all the answers

What measurement does millitex represent?

Weight in milligrams of 1000 metres of yarn Signup and view all the answers

What is the equivalent formula for calculating kilotex?

Kilotex = 1000 x (Weight in kilograms / Length in metres) Signup and view all the answers

If a yarn weighs 0.0050 grams and is 0.1515 metres long, how do you calculate its count in tex?

Tex = 1000 x (0.0050 / 0.1515) Signup and view all the answers

What is grex also known as?

Weight in grams of 10000 metres of yarn Signup and view all the answers

Which system calculates weight of yarn in kilograms over 1000 metres?

Kilotex Signup and view all the answers

What is the formula to convert Denier to Tex?

Tex = Denier x 9000 m / 1000 m Signup and view all the answers

If a fiber has a Denier count of 27, what is its Tex count?

3 Tex Signup and view all the answers

In the conversion from Denier to English, what does 'Ne' represent?

Count in English system Signup and view all the answers

What is the length used to calculate Ne in the English system?

840 yds Signup and view all the answers

What is the unit weight (WK) specified for the known system in the Denier conversion?

1 g Signup and view all the answers

In the conversion formula from Denier to Ne, what is the constant used for weight representation in the English system?

1 lbs. Signup and view all the answers

What factors are included when calculating Ne?

Length and unit weight of the required Denier Signup and view all the answers

Which relation correctly expresses the conversion from Denier to English count?

Ne = Denier x 1 lbs. / 840 yds. Signup and view all the answers

Which formula is used for conversion from Direct to Indirect System?

$NR = rac{LK}{NK} imes rac{1}{WK} imes WR$ Signup and view all the answers

What do the variables $N_R$ and $N_K$ represent in the formulas?

Count of required system and count of known system Signup and view all the answers

For conversion from Indirect to Direct System, which representation is correct?

$NR = rac{WK}{NK} imes rac{1}{LR} imes WR$ Signup and view all the answers

What is the primary distinction between Direct System and Indirect System in yarn numbering?

Direct System counts length per unit weight, while Indirect counts weight per unit length Signup and view all the answers

Which variables are involved in the formula for conversion from Direct to Direct System?

$N_R$, $N_K$, $WR$, $WK$, $LR$, and $LK$ Signup and view all the answers

In the Indirect to Indirect System conversion, which formula is applied?

$NR = NK imes rac{LK}{LR} imes rac{WR}{WK}$ Signup and view all the answers

What does $W_R$ represent in the conversion formulas?

Unit weight of the required system Signup and view all the answers

Which option correctly identifies the variable that changes between Direct and Indirect systems?

$N_R$ Signup and view all the answers

What is the relationship between the count number of yarn and its coarseness?

Higher count number indicates coarser yarn. Signup and view all the answers

Which fibers is the yarn numbering system generally used for?

Cotton, synthetic fibers, jute, and silk. Signup and view all the answers

Which measurement represents the shortest length unit?

Millimetres (mm) Signup and view all the answers

How many millimetres are in one foot?

304.8 millimetres Signup and view all the answers

What does the count of yarn directly express?

The size of the yarn. Signup and view all the answers

Which of the following correctly converts yards to metres?

1 yard = 0.9144 metres Signup and view all the answers

If you have 1 kilogram, how many pounds do you have approximately?

2.204 pounds Signup and view all the answers

Which measurement unit is equal to 1000 milligrams?

1 gram Signup and view all the answers

How many decimetres are there in a metre?

10 decimetres Signup and view all the answers

What volume unit does 1 ounce convert into?

28.34 grams Signup and view all the answers

Study Notes

Yarn Numbering Systems

Count indicates the fineness or coarseness of yarn, defined as mass per unit length or length per unit mass.
Yarn numbering systems are used to calculate yarn count, divided into direct (weight per unit length) and indirect (length per unit weight) systems.

Direct Yarn Numbering System

Measures the weight of a fixed length of yarn.
Higher count values indicate coarser yarns and lower values indicate finer yarns.
General formula: N = S × (W / L) where N is yarn count, S is standard length (m), W is yarn weight (g), and L is yarn length (m).

Types of Direct Yarn Numbering Systems

Tex (tex): Weight in grams of yarn per 1000 meters.
Denier (den): Weight in grams of yarn per 9000 meters.
Grex (dtex): Weight in grams of yarn per 10000 meters.
Grist: Weight in pounds of 14400 yards of yarn.
Millitex (mtex): Weight in milligrams of yarn per 1000 meters.
Kilotex (ktex): Weight in kilograms of yarn per 1000 meters.
Silk Count: Weight in drams present in 1000 yards, specifically for silk yarn.

Yarn Count Calculation Formulas

Tex: Tex = 1000 × (Weight in grams / Length in meters)
Denier: Denier = 9000 × (Weight in grams / Length in meters)
Grex (dtex): Grex = 10000 × (Weight in grams / Length in meters)
Grist: Grist = 14400 × (Weight in pounds / Length in yards)
Millitex: Millitex = 1000 × (Weight in milligrams / Length in meters)
Kilotex: Kilotex = 1000 × (Weight in kilograms / Length in meters)
Silk Count: Silk Count = 1000 × (Weight in drams / Length in yards)

Length and Weight Unit Conversions

Conversions provided between millimeters, centimeters, decimeters, inches, feet, yards, meters, and kilometers.
Also includes conversions between grains, milligrams, centigrams, grams, drams, ounces, pounds, and kilograms.

Yarn Count Conversion Formulas

Direct to Direct Conversion: NR = NK × (WR / WK) × (LK / LR)
Direct to Indirect Conversion: NR = (LK / LR) × (NK × WK / WR)
Indirect to Indirect Conversion: NR = NK × (WK / WR) × (LK / LR)
Indirect to Direct Conversion: NR = (WK / WR) × (NK × LK / LR)

Conversion Examples

Denier to Tex: Tex = Denier × (1000 / 9000), demonstrating simple conversion based on count values.
Denier to English: Uses similar principles to convert between different numbering systems.

Practical Applications

Higher counts represent coarser yarns, while lower counts indicate finer yarns, applicable across various materials such as cotton, synthetic fibers, jute, and silk.
Understanding these systems is crucial for textile manufacturing and fabric technology.

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Description

Explore the various yarn numbering systems used in fabric technology. This quiz focuses on the definition and calculation methods of yarn count, which indicates the fineness or coarseness of yarn. Test your knowledge on understanding how yarn properties are measured!