The Influence of Stitch Density and of the Type of Sewing Thread on Seam Strength

Having in mind the complex problems of technological process of sewing, as well as general demands for seams produced in garment production, this research should contribute the development of sewed seams breaking forces. Thus, many measurements of seam breaking forces have been conducted. These measurements enable us to define optimal strength of seam strength that improves the compliance of sewed seams parameters. This paper deals with the influence of the thread type and stitch density on the seam strength. The breaking forces and elongations at break were determined by the standardized method (SRPS 2062) and fabric (tape method) according to SRPS EN ISO 13934-1. Fabric samples used for seam testing were sewed by seam (1.01.01) and stitch type 301 with stitch densities 3, 4 and 5 cm-1. Optimal seam strength (130.9 Ncm-1) on the fabric T71, and at the same time the highest strength, has been noticed at the samples with seam line in weft direction with stitch density 5 cm-1, sewed with polyester thread 20x2 tex count, while on fabric T71 that value is 115.9 Ncm-1. According to obtained results, it can be concluded that stitch density (3 cm-1 ÷ 5 cm-1) and the type of sewing thread (cotton and polyester, K1 ÷ K5) have great influence on defining seam sttrength, their inconsistency may lead to great differences in seam behavior.