Knitted yarn requires higher yarn thickness, good flexibility, certain strength, elongation, and twist. During the process of forming knitted fabrics on a knitting machine, the yarn is subjected to various mechanical effects such as stretching, twisting, changing, and conflicting. To ensure normal production and product quality, knitting yarn should meet the following requirements:

1、 Yarn should have certain strength and extensibility

The strength of yarn is an important quality objective for knitting yarn. Due to the tension and repeated loading effects experienced by yarn during preparation and weaving, knitting yarn must have a certain strength. In addition, during the process of weaving into loops, yarn also needs to undergo twisting and deformation, so knitting yarn is required to have a certain degree of extensibility to facilitate the twisting into loops and reduce yarn breakage during the weaving process.

2、 Yarn should have outstanding softness

The softness requirements for knitted yarn are higher than those for woven yarn. Due to the fact that soft yarns are prone to twisting and changing, and make the coil structure in knitted fabrics uniform and have a clear and beautiful appearance, they can also reduce yarn breakage and damage to the coiling mechanism during the weaving process.

3、 The yarn should have a certain degree of twist

Generally speaking, the twist of knitted yarn is lower than that of woven yarn. If the twist is too large, the softness of the yarn will be poor, and it is not easy to be twisted or changed during weaving. It may also easily twist, causing weaving defects and damaging the needles; In addition, yarns with excessive twist can affect the elasticity of knitted fabrics and cause the loops to tilt.

But the twist of the yarn used for knitting should not be too low, otherwise it will affect its strength, increase the breakage during weaving, and cause the yarn to swell, resulting in simple pilling and pilling of the fabric, reducing its wearability. Therefore, selecting the right twist is an important way to choose yarn reasonably. Knitted fabrics have different twist requirements depending on their usage.

(1) Sweat cloth requires smoothness, tightness, smooth surface, clear patterns, and a higher twist of yarn that can approach the warp standard for weaving with the same thread density.

(2) The yarn used for outerwear should have a higher twist to enhance its stiffness and improve pilling and pilling.

(3) Cotton wool fabric and elastic fabric require a soft and elastic feel, and the yarn twist should be slightly lower. Generally, machines with the same linear density are selected to use weft yarn with a lower twist error. Velvet knitted fabrics are made of yarn, which requires less twist to facilitate the pulling of the fibers and ensure even thickness of the fibers.

The size of other twists also varies with the yarn density.

4、 The linear density of the yarn should be uniform and there should be fewer yarn defects

The uniformity of yarn density, also known as the uniformity of yarn dryness, is an important quality goal for knitting yarns. Uniform yarn is beneficial for knitting processing and ensuring fabric quality, making the coil structure uniform and the fabric surface clear.

Yarn defects are also an important target for needle cloth yarn. If there are coarse knots on the yarn, weaving cannot pass smoothly, resulting in yarn breakage or damage to the machine parts, and simple "horizontal stripes" and "cloud spots" are formed on the fabric surface, reducing the quality of the knitted fabric; If there are details on the yarn, the strength is insufficient here, resulting in simple breakage, affecting the quality of the fabric and reducing machine productivity. Due to the multiple loop forming systems on the knitting machine, it is not only required that the thickness of each yarn be uniform, but also that the difference in yarn thickness between each yarn be strictly controlled, otherwise it will form defects such as horizontal stripes and shadows on the fabric surface, reducing the quality of the fabric.

5、 Yarn should have outstanding moisture absorption properties

The ability of yarn to absorb moisture in the air is called hygroscopicity. The moisture absorption capacity of various fibers varies greatly, and the amount of moisture absorption varies with the temperature and humidity of the air. The yarn used for knitting production should have a certain degree of moisture absorption. Under the same relative humidity conditions, yarns with good moisture absorption not only have good conductivity, but also contribute to the stability of yarn twisting and the improvement of elongation, thus giving the yarn outstanding weaving performance.

6、 The yarn should have outstanding smoothness and a small coefficient of conflict

Knitted yarn should be as free as possible from impurities and oil stains, and should be very smooth. Unsmooth yarn causes severe wear and tear to the machinery, causing simple damage to the machinery. Additionally, there are many flying flowers in the workshop, which not only affect the health of workers but also impact the productivity of knitting machines and the quality of fabrics.

Article source: Fancy Thread Manufacturer

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