Working Principle of Circular Knitting Machines

Working Principle of Circular Knitting Machines

Circular knitting machines are capable of producing knitted fabrics. Initially, these machines produce unfinished grey fabric, which in the textile industry is also referred to as "raw fabric" or "gray cloth". These terms all denote fabrics that have not yet undergone dyeing, printing, finishing, and other post-processing treatments.

The clothes we wear, such as underwear, sportswear, T-shirts, etc., initially exist in the form of grey fabric.

Grey fabric represents a critical stage in the knitting production process, directly manufactured on circular knitting machines through knitting technology. At this stage, the fabric may appear somewhat coarse, typically in its raw material color (e.g., white for cotton or specific colors for synthetic fibers), and might lack the softness, elasticity, or other characteristics required in the final product.

After the grey fabric stage, the fabric usually undergoes a series of post-processing procedures like dyeing, printing, finishing, washing, drying, etc., to achieve the desired appearance, feel, and performance. These post-treatment processes can improve the fabric's color, pattern, texture, and durability, making it more suitable for end-use applications such as clothing or other textiles. Therefore, the grey fabric produced by circular knitting machines is a crucial part of the manufacturing process for knitted products, providing a foundation for subsequent processing and finishing.

The working principle of circular knitting machines is akin to the stable operation of a car, where an electric motor drives smaller gears via belts and pulleys, which then drive the larger gear equipped with needle cylinders. Simultaneously, the take-up roller, coaxial with the pulley, performs the function of winding the fabric.

The knitting capability of circular knitting machines differs between single jersey and double jersey. On single jersey knitting machines, the process starts with the transport system. Yarn is fed from spools into the knitting area through a yarn feed system. Then, the yarn is captured by needles and moves along tracks formed by cams. Subsequently, loops are gradually formed on the needles, similar to knitting a sweater. Double jersey knitting refers to the machine's ability to knit both sides of the fabric simultaneously, using upper and lower needle beds for bidirectional knitting technology, featuring both synchronized needle pressing and lagging needle pressing methods, capable of knitting high-density rib structures and other diverse double-sided patterns. When the machine operates, loops are formed on both the front and back sides of the fabric. These loops interlace meticulously to ensure the two layers are woven together. This interlacing gives double jersey knitted fabrics their distinctive density.

Technology for circular knitting machines continues to advance; although the basic working principles largely remain unchanged, existing technologies already meet most needs due to the demand for finished fabrics. However, technological progress does not stop here. Future upgrades will undoubtedly focus on enhancing efficiency, reducing costs, and optimizing output.