The Research And Application Of Heat Sealing Process Of Small Hard Pack

The defects existing in the side of cigarette packet severely impair packaging quality as the film of the hard packet is heat-sealed by the CH film packing machine of GDX2unit. The CH side-heat-sealing system and the structure of iron, primary factors influencing the packaging quality, are regarded as the objects of study, on which the paper is based, the process of heat-sealing system and the cause of the defects is analyzed. The heat transfer theory and heat-sealing mechanism of film have been summed up and the heat-sealing characteristics of the material of the cigarette film, BOPP, it has been discussed. By the research based on the heat-sealing iron and material of the particular object, the optimal technological parameters of the course that the hard packets are handled by side-heat-sealing system have been obtained and the structure of iron has been greatly improved.In order to improve the heat-sealing quality of the CH film packing machine and explore the optimal technological parameters among the heat-sealing process of the CH side-heat-sealing iron. The research mainly includes two parts:(1) Researching the material properties of heat-sealing film and analyzing the main factors that affect the quality of the BOPP film with the heat-sealing tests for BOPP film;(2) Analyzing the effects of the CH side-heat-sealing iron, modifying the designation of the structure of the previous iron, using the ANSYS to analyze the heat field of the iron and simulating the mechanism of thermal conductivity of the BOPP film and the iron.With the analysis of the heat-sealing material and mechanism in the process of the operation of GDX2packing machine, several parameters such as heat-sealing temperature, heat-sealing pressure and heat-sealing time, which affect the heat-sealing quality, can be obtained. With some tests to simulate the heat-sealing process, the sealing temperature affect the quality of heat-sealing process, followed by sealing time, and then sealing pressure with the regression analysis. According to the conditions of the devices and the specific heat-sealing material, the best production parameters of side-heat-sealing technics for a product (the hard packet) can be obtained as follows:the heat-sealing temperature is121℃, the heat-sealing time is0.19s, and the heat-sealing pressure is0.3MPa. For the distribution of the thermal field of the heat-sealing face for the existing iron is uneven, so a solution that the iron hole by a conventional single-hole can be designed as a two-hole structure.The finite element mathematical model of the three-layer BOPP film is established with ANSYS software, The load is set as the perfect hear-sealing temperature121℃, and the figures simulate the thermal conductivity of the film, which shows that BOPP film can achieve the best heat-sealing effect in the best sealing temperature. With the finite element thermal field analyses for the structures of the previous iron, the temperature distribution of the improved iron structure working face is more uniform, and the heat transfer effect of the heat-sealing face is more uniform.