Análise do degaste das agulhas de costura industrial

Abstract

The sewing process is one of the most important segments in the clothing industry, being an essential part in the assembly of most textile products through various industrial machines. Given the variety of machinery to meet the range of sewing operations existing in the confection, it is necessary specific needles and thicknesses suitable for the pattern of the different fabrics on the market, aiming at the desired quality in the sewing. Therefore, it is extremely important to pay attention to the sewing machine needle, and its replacement is essential to have a quality sewing; however, machine operators only do so when they perceive it to be badly damaged, bent or when it breaks. Needle wear is a problem faced by the sewing industries and understanding the causes of wear and applying this knowledge to reduce needle temperature during high sewing speed can bring greater benefits. This dissertation aimed to identify the types of needle wear in the sewing process and its possible causes. To carry out the present study, needles were collected in a micro-enterprise that manufactures clothing, two different sizes of needles were collected, and 3 machines and 4 types of sewing process were also considered. This selection aimed to study the influence of sewing parameters and fabric type on needle wear. The methodology consisted of three steps: collection of needles in the factory environment, identifying the reasons that led the operator to replace them, second step was a visual analysis and the third was the characterization of wear with the aid of scanning electron microscopy. In the visual analysis, damages such as rougher ("blunt") needle and needle breakage were identified, damages that justified the replacement of the needle. The operating time of each needle is an average of eight hours. Regarding the needle wear mechanisms, I observe a deformation in the needle tip, resulting in its flattening. There is also a widening of the needle eye due to wear caused by friction with the thread. There were signs of adhesion of materials to the surface of the needle.