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. Optimal seam strength (130.9 Ncm) 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, sewed with polyester thread 20x2 tex count, while on fabric T71 that value is 115.9 Ncm. According to obtained results, it can be concluded that stitch density (3 cm ÷ 5 cm) 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.
Performance Analysis of the Mechanical Behaviour of Seams With Various Sewing Parameters for Cotton Canopy Fabrics
This study aims to develop a tool to predict the behaviour under a load of textile seams, to enable the selection of materials for specified end uses in the parachute industry. The strength of an assembly is directly dependent on the strengths of the various joints and seams required to make the structure. This study seeks to understand the performance of seams woven into cotton fabrics. A combination of five parameters has been studied here. Two properties, the seam strength and seam efficiency (% ratio of seam strength to fabric strength), are used as performance estimators. Both were found to vary significantly not only with the primary parameters but also with the interactions of primary parameters as well. That is, they change with each of the primary parameters but vary in a different manner when other parameters also change. Multiple regression has been used to construct preliminary predictor equations.
Needle Heating during High-Speed Sewing12
A review of the literature and extensive field interviews have been conducted on the subject of needle heating in high-speed sewing. As a result of this investigation, a survey of the current state of the art and knowledge available in the field has been completed and is presented in the following categories: (1) the nature of the problem and the difficulties which arise in commercial operations; (2) quantitative methods of measuring needle temperatures; (3) the influence of machine factors such as sewing speed, length of sewing time, and needle design on the heat generated during sewing; (4) the influence of material factors such as fabric structure and finish, layers of fabric, and sewing thread on needle heating; (5) techniques for alleviating needle heating problems; and (6) the mechanism of generation and dissipation of heat in the sewing process. Some heretofore unpublished data are presented.