The bag making machine can make bags of different specifications. These bags are widely used in food and chemical industry. What is the heat sealing temperature of the bag making machine?
The PVC bag making machine needs a heat sealing temperature in the process of bag making. Its function is to heat the adhesive film to an ideal viscous flow state. When selecting the heat sealing temperature, it is necessary to comprehensively consider the characteristics of the heat sealing material, the thickness of the film, the times of heat sealing pressing, and the size of the heat sealing area. If the pressing times of the agreed parts are increased, the temperature can be appropriately adjusted lower. If the heat sealing area is increased, the heat sealing temperature can be adjusted higher.
Because PVC plastic is an amorphous polymer with no fixed melting point, there is only a melting temperature range, that is, a temperature range between the solid phase and the liquid phase. When heated to this temperature range, the film will enter a molten state. The upper and lower limits of the temperature range represent the decomposition temperature and viscous flow temperature of PVC, respectively. The difference between them is the key to determine the difficulty of heat sealing.
During the bag making process of PVC bag making machine, the heat sealing strength is affected by the heat sealing temperature. The higher the heat sealing temperature, the heat sealing strength will also increase. However, at a certain temperature, the heat sealing strength will not change. If the heat sealing temperature is too high, the heat sealing material at the welding place will be damaged, and the heat sealing strength of the seal and the impact resistance of the bag will be reduced. Therefore, the heat sealing temperature should be higher than the melting temperature of the heat sealing material, and the temperature should not be too high.
