Studies On Bag-making System Of Pantyhose Packaging Machine

The bag making system is an important part of the whole pantyhose packaging machine,it directly determines working efficiency and the quality of finished products.The main principle of the system is heat sealing and cutting.It melts the plastic film of the heat cutting position into viscous flow state using electrical heating,and then cuts the plastic film,while the upper and lower material layers are fused together,which can maintain a certain strength and good seal ability when cooled.Since the problems that the burr is too long or the strength is not enough often happen in the working process of bag making system,this paper completes the following work.(1)It introduces the technology processes and methods of dragging film,folding,heat sealing and cutting before the plastic film is made into bags,it focuses on the plastic film folding methods and mechanism.(2)The mathematical model of plastic film thermal deformation is established,the factors thataffect the temperature distribution of the heat sealing and cutting blade is obtained using finite elements analysis software ANSYS;loading the different temperature fields on the plastic film,the thermal deformation displacement of the plastic film under different temperature loads is obtained,by comparing,it can be obtained that the main causes of burrs formation are thermal expansion and thermal stress of the plastic film.(3)Experiments are designed to measure the burr length and heat sealing and cutting strength,based on the experimental data and statistical software,the curves indicating the relationship between burr length,heat sealing and cutting strength and heat sealing and cutting temperature,pressure and time are obtained respectively and the mathematical models of burr length and heat sealing and cutting strength are established,by comparing the theoretical value and the experiment results,it verifies reasonability of the models,though calculating the conditional extreme values of the models,the optimized process parameters are obtained to reduce burr,decrease burr length and increase heat sealing and cutting strength,meeting the strength and aesthetics requirements at the same time.Though this research,the work efficiency of the bag making system and the quality of the bag making are improved,so as to improve the production efficiency and finished packaging products of the packaging machine.