Yarn classification, process and function

What is yarn

Yarn includes yarn and thread, which is a general term for yarn.

Yarn is a form of fiber aggregates that are slender and soft

The difference between yarn and thread

Yarn is made by twisting bundled fibers

Thread is made by twisting two or more strands of yarn

Classification of yarns

1: Classification by thickness
2: Classification by use
Weaving yarns: warp, weft, pile yarn, decorative yarn.

Knitting yarn: weft knitting yarn, warp knitting yarn, pile yarn, decorative yarn, towel yarn, sewing thread yarn, embroidery thread yarn, civil thread yarn, special yarn, functional yarn.

3: By fiber type

Pure spinning yarn: cotton yarn, hemp yarn, staple fiber, filament yarn, wool yarn, silk spinning yarn, blended yarn.

4: According to the spinning system

Carded yarn, combed yarn, roving yarn, worsted yarn, etc.

5: According to the shape and structure
Single yarn, plied yarn, monofilament, multifilament, bulked yarn, textured yarn, core-spun yarn, fancy yarn, slub yarn, untwisted yarn, wrapped yarn, etc.

6: According to the spinning method

Ring Yarn: Ordinary Ring Yarn, Compact Yarn, Siro Yarn.

Open-end spinning: open-end spinning, air-jet spinning, dust cage spinning, electrostatic spinning, self-twist spinning, compound spinning, etc.

Spinning process and function

1: The purpose of matching cotton

1. Meet the requirements of yarn quality.

2. Keep production relatively stable.

3. Make full use of the characteristics of various raw materials.

4. Reasonably reduce costs.

Two: cotton blending method

1. Artificial blended cotton

2. Cotton bales blended with cotton

3. Cotton sliver blend

Three: open and clean cotton and its function

1. Open: Open, loosen the compressed fiber raw materials into smaller blocks or bundles of fibers (several mg to tens of mg/block).

2. Clean: remove the larger impurities and defects (about 60%) in the fiber raw material.

3. Mixing: mixing, preliminarily mixing fibers of different specifications and properties.

4. Uniformity: make semi-products (fiber rolls or fiber streams) with a certain degree of uniformity that are suitable for the processing requirements of the next process.

*The length of the fiber roll is between 34.2~43.2m and the weight is 16~20kg.

Fiber roll dry weight:

Thick yarn 420~450g/m Medium yarn 390~420g/m

Fine yarn 360~390g/m Extra fine yarn 320~360g/m

Four: Carding and function

1. Comb: Carding, carefully combing the fiber blocks or bundles transferred from the previous process to make them into a single fiber state.

2. Impurity removal: The fine impurities and defects in the fibers are further removed by carding.

3. Mixing: The fibers are thoroughly mixed.

4. Sliver: The fibers are gathered together to form a strip, which is called a sliver, and is regularly placed in the can to facilitate processing in the next process.

Dry weight of raw sticks:

Yarn above 32tex 22~28g/5m 20~30tex 19~26g/5m

12~19tex 16~24g/5m Below 11tex 16~22g/5m

Five: Combing and function

1. Combing: fine carding, finely carding the sliver made from the carded sliver to further straighten, parallel and separate the fibers (the parallel straightness of the fibers can be increased from 50% to 90% of the sliver) about)

2. Exclusion: Short fibers below a fixed length (below 16.5mm), the exclusion rate is about 45%, and the uniformity of the fibers is improved.

3. Impurity removal: remove neps and impurities contained between fibers.

4. The combed sliver with uniform and certain weight is made.

5. The combed sliver is coiled into the can according to a certain rule, so as to facilitate the processing of the next process.

Quantity of combed evenness:

Extra fine yarn: 10.5~14g/5m

Small and medium yarn: 13.5—15.5g/5m

T/C yarn 18.5—21g/5m

Six: drawing and its role

1. Combine: Combine, combine 6 to 8 carded or combed slivers to make up for the uneven thickness of the sliver to improve the uniformity of the sliver.

2. Drafting: At the same time of merging, drafting (drawing, elongation) is slightly larger than the number of merging.

3. Mixing: Through the action of merging and drafting, the fibers are fully mixed.

4. Straightening: Under the action of drafting, the fibers are further straightened and paralleled.

5. Sliver making: make a certain weight of fiber bundles, and regularly circle them into the cans to facilitate the processing of the next process.

Quantity of cooked sticks:

Above 32tex 19~23g/5m 20~30tex 15~20g/m

13~19tex 13~18g/5m 9~13tex 11~15g/m

*Selection of the number of draw frames:

pure cotton

Chemical fiber blend

Seven: woolen spinning and function

1. Drafting: The sliver is stretched by 5~12 times (the stretching ratio of the imported roving machine is 2.5~24.2 times) to make a roving of a certain fineness.

2. Straightening: Through drafting, the fibers are further straightened and paralleled.

3. Twisting: apply a small amount of twist (2.13~1.01 twist/10cm) to the drafted whisker, paraffin emulsion india, and spin it into a slightly stronger roving.

4. Winding: The roving is wound and formed in an orderly manner, which is convenient for the unwinding of the worsted spinning process.

Roving dry basis weight:

Above 32tex 5.5~10.0g/10m 20~30tex 4.1~6.5g/10m

9.0~19tex 2.5~5.5g/10m Below 9.0tex 1.6~4.0g/10m

*In the old-fashioned roving process, it generally takes two passes, or even three roving processes when spinning high-count yarns.

The first roving machine is fed with a single sliver, and is spun into 660~1250tex (0.9s~0.47s) first roving after 3~4 times of mechanical drafting; the second roving machine is fed with double first rovings , after 4~5 times of mechanical drafting, it is spun into 230~650tex (2.5s~0.9s) secondary roving; the three-lane roving machine is fed with double secondary rovings, after 4~5 times of mechanical drafting (weight Drafting 2~2.5 times), spun into three rovings of 100tex~220tex (5.8s~2.7s).

Eight: worsted spinning and function

1. Drafting: The worsted spinning process is the last process of the yarn. Therefore, drafting the roving to a certain number is the primary task of the worsted spinning process.

2. Twisting: Twist the drawn whisker to make it a spun yarn with a certain strength.

3. The spun yarn is wound on a suitable bobbin in an orderly manner, which is convenient for post-processing and unwinding during use.

*The draft ratio of worsted spinning is generally 10 to 50 times.