SLIPPAGE AND GRINNING BEHAVIOUR OF LOCKSTITCH SEAMS IN ELASTIC FABRICS UNDER CYCLIC LOADING CONDITIONS

In this study, slippage and grinning behaviour of lockstitch seams on elastic woven fabrics (seam type 1.01.01 SSa-1 stitch type 301) under cyclic loading conditions has been analyzed. The influence of repeated extension and recovery was investigated. For this purpose two different fabric types with two different weft densities and with two different elastane yarn types were taken as samples for the experiments. In total six samples having different specifications were obtained. The effects of mechanical properties of fabrics on the amount of seam slippage and seam grinning are experimentally investigated and statistically analyzed. Seam slippage and grinning on the sewn fabrics increase with decrease weft density and with increasing fabric extensibility. The slippage results of the samples were between 7-14 mm and grinning results were between 0.86-0.94 mm. under cyclic loading conditions. Photographs were taken with an optical microscope to show the slippage and grinning behaviour of the elastic fabrics after 300 cyclic loading conditions.