Investigation On Transverse Defects Of Kinttde Fabrics On Circular Knitting Machine

In recent years,due to the improper use of yarn materials and the lack of production management and technology,the fabric quality of some knitting enterprises has seriously deteriorated.As a typical defect of knitted fabrics,the transverse defect of circular knitting fabric occurs frequently in production.The transverse defects will directly affect the appearance of the knitted fabric,resulting in a decline in the quality of the knitted fabric,and even lead to the scrapping of the entire batch of fabrics,which will not only bring huge economic losses to the enterprise,but also seriously affect the company's image and even cause economic disputes.Transverse defects,also known as cross bar or course mark,which belongs to one kind of horizontal defects of knitted fabrics,are regular or irregular appearance of one or several undersigned courses or stripes along the course of the weft knitted fabric,and the loops of courses or stripes are different from other normal loops in terms of spatial structure or color.How to correctly handle and analyze the problem of transverse defects,reduce or eliminate the occurrence of transverse defects is an important issue to ensure the normal production of enterprises and improve the quality of knitted fabrics.This article first starts with the production process of circular knitting fabrics,focusing on the theoretical analysis of the causes of the transverse defects of knitted fabrics from the yarn material and the knitting process,mainly including the influence of yarn color difference,sliver,twist and yarn feeding mechanism,knitting mechanism,drawing and crimping mechanism and equipment installation accuracy on transverse defects.In addition,some typical transverse defects in actual production were inspected and analyzed,at the same time,the common inspection methods and analysis procedures for transverse defects of circular knitting fabrics were summarized.Subsequently,the related practical explorations of the impact of yarn materials and knitting process on the transverse defects of circular knitting fabrics were carried out respectively,in terms of yarn materials,the effects of the wrong yarn knitting and mixed batch knitting on the transverse defects of the circular knitting fabric were simulated separately,at the same time,the influence of the twist of the yarn on the transverse defects of the circular knitting fabric was also investigated;in the knitting process,the yarn feed tension and the concentricity of the sinker triangle of the machine with transverse defects were measured and analyzed.The results show that the difference in the color of the yarn,the uneven sliver and twist of the yarn,the abnormal fluctuation of the yarn tension,and the poor installation accuracy of the equipment can lead to different levels of transverse defects.Based on the above work,the MATLAB image processing toolbox was used to process and analyze the image of the transverse defects of the circular knitting fabric.First,the grayscale conversion,mean filtering and histogram equalization of the transverse defect image were preprocessed,then,the maximum inter-class variance method was used to segment the transverse defect,and the segmented defect image is further optimized using corrosion and dilation operations,the results show that this method can basically achieve the segmentation of transverse defects.Afterwards,the segmented transverse defects were identified,and the transverse defects were marked and reconstructed according to the extracted position information.Finally,it is evaluated based on the characteristics of the transverse defects.