Double-sided Circular Knitting Machine: Structural Principle and Production Application Guide

Double-sided circular knitting machine Structural Principle and Production Application Guide: The double-sided circular knitting machine is a core equipment in the field of knitting and weaving. Through the coordinated loop formation of the upper and lower double-needle beds, it can weave double-sided fabrics with tight structure and excellent elasticity. It is widely used in the large-scale production of thermal underwear, sweatshirt jackets, high-end home textiles and other products, and has the significant advantages of high weaving efficiency and diverse fabric styles. I. Core Structural Features of the Double-sided Circular Knitting Machine: Compared with the single-sided machine, the double-sided machine is more complex in structure. The core design is centered around the precise linkage of the double-needle bed to ensure that the upper and lower knitting needles work in coordination to complete the circular action: 1. Knitting mechanism: The core of the double-needle bed’s coordinated circular action, the upper and lower needle beds and the syringe: The whole machine is equipped with two circular needle beds (or lower syringe + upper needle tray), the walls of the needle beds are covered with needle slots, and the upper and lower knitting needles are arranged relatively. During operation, the upper and lower knitting needles alternately hook the yarn and cooperate with each other to form a closed double-sided loop structure, which determines the basic structure of the fabric. Specialized knitting needles and settling plates: Knitting needles are divided into upper needles and lower needles, and the needle type is suitable for the circling requirements of different double-sided tissues (such as cotton, wool, ribbing). The settling plate is set between the upper and lower needle beds, assisting in the pulling, bending and unwinding of the coils, preventing the coils from loosening or deforming, and ensuring the flatness of the fabric surface. Triangular system: It consists of two independent triangular devices, the upper triangle and the lower triangle, which respectively control the lifting trajectories of the upper and lower knitting needles. By adjusting the arrangement Angle and height of the triangle, it is possible to switch between various double-sided structures such as cotton-wool, ribbed, air layer and jacquard, meeting the production demands of differentiated fabrics. 2. Yarn feeding mechanism: The multi-path precise tension control adopts a multi-path independent yarn feeding system, which can simultaneously convey various yarns of different materials and colors, and is suitable for the weaving of complex double-sided fabrics such as colored stripes and jacquard. Each yarn feeder can independently adjust the tension to ensure that the tension of the ground yarn matches that of the patterned yarn, avoiding defects such as loose threads and cloud spots on the fabric surface caused by uneven tension. The high-end model is equipped with an electronic yarn feeding device, which can dynamically adjust the yarn feeding amount in real time according to the weaving speed and fabric structure. It is particularly suitable for the precise conveying of elastic yarns (such as spandex), ensuring the uniform elasticity of the elastic double-sided fabric. 3. Drawing and winding mechanism: The drawing roller, which is designed to match the characteristics of double-sided fabrics, adopts a wide-width synchronous drawing design, precisely matching the fabric width. The drawing speed is strictly synchronized with the weaving speed of the double-needle bed to prevent problems such as curling edges and stretching deformation of double-sided fabrics due to uneven drawing. The winding device is equipped with an intelligent tension adjustment system, which can automatically adjust the tension of the wound fabric according to the fabric weight and thickness, ensuring that the fabric is tightly wound and neatly arranged, while avoiding damage to the coil structure of the double-sided fabric. 4. Transmission and Electrical Control System: The transmission mechanism adopts a variable frequency speed regulation motor, combined with a high-precision gearbox, to achieve stepless smooth speed regulation, meeting the weaving speed requirements of different structures and yarns. When operating at high speed, the entire machine has low vibration and noise. The electrical control system is equipped with PLC and touch screen, supporting the storage and invocation of weaving parameters, and allowing for one-click switching of fabric structure. Some models integrate fault diagnosis and remote monitoring functions, which can monitor faults such as yarn breakage and needle damage in real time, reducing downtime losses. Ii. Key production Process Points of Double-sided Circular Knitting Machine 1. Yarn Selection and pretreatment: Prioritize the use of yarns with uniform dryness and stable twist. Pure cotton yarn is suitable for weaving skin-friendly underwear fabric, polyester-cotton blended yarn is suitable for wear-resistant outerwear fabric, and spandex core-spun yarn is used for the production of elastic double-sided fabric. The yarn needs to undergo pretreatment such as humidification, pre-shrinkage and anti-static treatment to reduce the breakage rate and electrostatic adsorption of impurities during the weaving process, and ensure the smoothness of the fabric surface. 2. Process parameter adjustment and needle bed gap adjustment: Precisely adjust the distance between the upper and lower needle beds based on the yarn fineness and fabric thickness. A gap that is too large can easily lead to missed stitches, while a gap that is too small can easily wear out the knitting needles and cause yarn breakage. Tension and speed matching: For light and thin double-sided fabrics (such as cotton and wool underwear fabric), the yarn feeding tension and weaving speed should be reduced. For thick fabrics (such as air layer sweatshirt fabric), the tension and speed can be appropriately increased to balance production efficiency and fabric quality. 3. Daily maintenance of the equipment: Regularly clean the impurities in the needle slots and triangular tracks of the upper and lower needle beds to prevent the knitting needles from getting stuck. In accordance with the requirements of the equipment manual, regularly add special lubricating oil to key components such as the needle bed and triangle. The oil output of the oil needle should be controlled at 1-2 drops per minute to prevent oil contamination of the fabric. Regularly inspect the wear and tear of the knitting needles and settling plates, and replace deformed or damaged parts in a timely manner to prevent fabric defects such as holes and missed stitches. Iii. Typical application Scenarios of Double-sided Circular Knitting Machines 1. In the field of clothing fabrics: weaving cotton and wool fabrics (for thermal underwear), ribbed fabrics (for collars and cuffs), air layer fabrics (for outerwear of sweatshirts), and double-sided jacquard fabrics (for high-end fashion). 2. Home textile field: Weaving double-sided flannel, mattress fabric, pillowcase fabric, etc. The fabrics are thick and durable, with both warmth retention and breathability. 3. In the field of industrial fabrics: Weaving double-sided filter fabrics, protective fabrics, etc., the strength and filtration performance of the fabric surface are enhanced by adjusting the fabric structure.