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What is the heat sealing temperature of bag making machine

2021-02-05  803

Bag making machines can produce bags of different specifications. These bags are widely used in food and chemical industries. What is the heat sealing temperature of bag making machines? Ruixing plastics will give you a detailed introduction today.

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 choosing the heat sealing temperature, it is necessary to consider comprehensively according to the characteristics of the heat sealing material, the thickness of the film, the times of hot pressing and the size of the heat sealing area. If the hot pressing times of the agreed parts increase, the temperature can be adjusted down appropriately. If the heat sealing area increases, the heat sealing temperature can be adjusted up.

Because PVC plastic is an amorphous polymer, there is no fixed melting point, so there is only one melting temperature range, that is, a temperature region between the solid phase and the liquid phase. When heated to this temperature range, the film will enter the 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.

In the process of PVC bag making machine, the heat seal strength is affected by the heat seal temperature. The higher the heat seal temperature is, the higher the heat seal strength will be. However, when the temperature reaches a certain level, the heat seal strength will not change. If the heat sealing temperature is too high, the heat sealing material of the welding joint will be damaged, and the heat sealing strength of the sealing 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.