Definition of criteria for quality joint of knitted fabrics using lockstitch sewing machines

The object of research is the thread joint of knitted fabrics, made on lockstitch sewing machines for shuttle stitch. The aim of this work is to determine the criteria that affect the quality of the thread joints of knitted fabrics. As a result of the work, the process of formation of shuttle stitches during the grinding of dense knitted fabrics is considered in detail. The criteria influencing quality of thread joints of knitted cloths are determined. The condition of high - quality loop formation without skipping stitches in the processing of dense knitted fabrics on universal grinding machines is established. It is determined that the quality of looping depends on the coefficient of friction of the sewing thread on the material and on the needle, i.e. on the properties of rubbing surfaces, as well as the area of contact of the thread with the surface of the material and the needle. The value is calculated which should not exceed the area of contact of the thread with the needle when stitching polyamide knitted fabrics with polyamide sewing threads to ensure quality looping. The field of application of the results is light industry.