Knitting skills include weaving, knitting, knitting and non-knitting, among which knitting is divided into warp knitting and weft knitting. The orientation of warp knitting in weaving is shown in the following figure, and warp knitting lining is a kind of weaving skill belonging to knitting category. The warp knitting lining uses one or several groups of yarns placed in parallel to form a knitted fabric by looping together on all working needles of the warp feeding machine. This method is called warp knitting, and the formed knitted fabric is called warp knitted fabric.
Knitting is a way to form fabrics, and the fabrics it forms are called knitted fabrics. Knitted fabrics are made by deception of loops. Knitted fabrics can be divided into warp knitted fabrics and weft knitted fabrics according to the looping direction of yarns in fabrics. The titles of warp knitting and weft knitting come from weaving. Weaving is a stale textile skill. Woven fabrics are interwoven by longitudinal warp yarns and transverse weft yarns. In warp knitted fabric, the same yarn forms loops along the warp direction (longitudinal direction) of the fabric; In weft knitted fabrics, the same yarn forms loops along the weft direction (transverse direction) of the fabric. Only one yarn (or a limited number of yarns) is needed to form weft knitted fabrics, while one or several groups of yarns are needed to form warp knitted fabrics, and each group of yarns is composed of many yarns. Characteristics of warp knitted lining fabric.
Knitted fabrics are made up of loops connected in series, which can be divided into weft knitted fabrics and warp knitted fabrics according to different knitting methods. Weft-knitted fabrics, such as ordinary sportswear, underwear, socks and hand-knitted sweaters, are woven transversely with weft yarns in sequence to form loops. Warp knitting is the knitting of all knitting needles at the same time. The structure, properties and production methods of warp knitted fabrics have the following characteristics:
1. The production efficiency of warp knitted lining fabric is high, with the high machine speed reaching 3600rpm, the width reaching 210 inches and the efficiency reaching 98%.
2. Compared with weft knitted fabrics, warp knitted lining fabrics generally have less extensibility. Most weft knitted fabrics have remarkable extensibility in transverse direction, while the extensibility of warp knitted fabrics is related to the number of bars and the structure. Some warp knitted fabrics have extensibility in both transverse and longitudinal directions, while others have good dimensional stability.
3. The warp knitted fabric has good anti-shedding property. It can make use of different structures to reduce the shedding of stitches caused by broken yarns and holes in weft knitted fabrics.
4. Because warp knitted fabrics can use yarns with different thicknesses and carry out different weft insertion knitting, they can form different mesh structures, and the pattern transformation is simple, so almost all fabric structures can be knitted.
5. Compared with other production technologies, warp knitting technology is practical in producing mesh fabric. The mesh fabric produced can have different sizes and shapes, and the shape of the fabric is stable without any special finishing to make the fabric firm.
6. Warp knitting can produce shaped products, such as pantyhose, briefs, seamless tights and gloves.
Compared with woven and weft knitted fabrics, warp knitted fabrics are relatively stable in terms of structural stability. Woven fabric is interwoven by warp yarns and weft yarns, which has edge tearing property, and warp yarns or weft yarns can be pulled out from the edge of cloth; Weft-knitted fabric is woven by one weft yarn, which is loose, and the loops of the hem can be loose from the fabric. The warp knitted fabric is woven by many yarns, and the connected yarns are nested with each other, so the structure is relatively stable. In structural elasticity (elasticity produced by fabric structure), woven fabric has very little structural elasticity in warp and weft direction, while weft knitted fabric has great structural elasticity in warp and weft direction, and warp knitted fabric has structural elasticity between them.