Abstract:
Garments business is one of the most challenging businesses in the world. To survive in this competitive market, it is necessary to consider various techniques both before and during the start-up of the business. Product design, sampling, cutting, sewing, embellishment, finishing, and other processes are all part of the garment manufacturing process. To achieve the desired productivity, all of these activities must be performed in a synchronized, planned, and timely manner. Sewing is a crucial part of the manufacturing process. The purpose of this study was to investigate the effect of non-productive time (NPT) on sewing production at various efficiency levels (55, 65, and 75%). However, not only does efficiency influence NPT, but so does the complexity of the garment. Therefore, in this study, basic (T-shirts), semi-critical (hoodies), and critical (jackets) products were chosen to identify the NPT of a renowned garment factory, namely Oxford Knit Composite Ltd. (Pretty Group). The time study method, one of the most effective tools, was used in this study. This study reveals that at the highest efficiency level (75%), the production deviation due to NPT for T-shirts, hoodies, and jackets was 19.7, 8.8, and 6.3 pcs/h, respectively. However, if NPT is not controlled, output will not increase significantly. The NPT of T-shirt, hoodie, and jacket was about 0.4, 0.8, and 2.9 min, respectively. Additionally, NPT has a proportional relationship with SAM and product’s complexity. It is worthy to mention an annual loss of 21465, 25927, and 29640 USD for T-shirts, hoodies, and jackets, respectively, that occurs at a 75% efficiency level. Therefore, it is recommended to reduce the NPT to maximize profit and productivity.
