FEA Modeling of Needle Heating in High-Speed Industrial Sewing

Understanding the causes of needle heat-up in sewing machines is essential for better sewing performance and efficiency. This paper introduces an FEA model to predict needle temperature under different sewing conditions. It employs the implanted thermocouple method to measure needle temperature during high-speed industrial sewing. Instruments used include K type thermocouples, detector thermocouple end devices, and a Brother S7200C Lockstitch Sewing Machine. To fully understand the intricate nature of the process, geometric modelling of fabric unit cells and 3D modelling of sewing needles are undertaken. The sewing needle is precisely modelled using Parasolid, and fabric geometry is produced using the TexGen tool. Based on the ADAMS tool, a simulation model of the needle bar movement is created to carry out kinematic simulation analysis. The paper discusses the meshing of fabric and needle in ANSYS Workbench, incorporating material attributes and boundary conditions for heat flux and convection. The FEA model takes into account variables such as heat flux caused by friction, needle conduction, and fabric conduction. The thermal conductivity, density, specific heat of the sewing needle, warp yarn, weft yarn, and air were chosen as the material characteristics for the analytical method. The model's accuracy is validated through experiments, with a high correlation coefficient of 0.9969 and mean absolute error of 0.635%. It is concluded that the FEA model provides a valuable tool for predicting and managing needle heating during sewing operations, particularly when working with materials requiring precise temperature control.