Impact of stitch length on sewing needle temperature

In this article the sewing needle heat is measured without sewing thread and with sewing thread at different stitch density (stitches per inch or SPI) of lock stitch sewing machine by thermocouples. Two methods are used to measure sewing needle heat, touch thermocouple method and inserted thermo couple method. Needle temperature is measured after periodic 10, 20, 30 and 60 seconds of sewing operation. Whereas the machine running at speed from 1000 r/m to 4700 r/m. It is observed that decreasing stitch length causes an increase in the temperature of the sewing needle. Stitch density shows same influence on needle for sewing with thread and without thread. It is observed from our research that at SPI of 14 the needle temperature with thread rises to 259 °C at 4000 r/min of machine. It is recommended to use minimum stitch density.