The Importance Of Controlling The Temperature And Pressure When The Aluminum Foil Bag Is Heat Sealed

In the actual production process of aluminum foil bags, due to the influence of heat sealing pressure, bag making machine speed and composite substrate thickness, the actual temperature of heat sealing is often higher than the melting temperature of heat sealing materials. The smaller the pressure of heat sealing, the higher the temperature of heat sealing; Similarly, the faster the machine speed, the thicker the surface material of the composite film, and the higher the actual temperature of the heat sealing required.

If the heat sealing temperature is lower than the softening point of the heat sealing material, no matter how the pressure is applied or the heat sealing time is extended, the heat sealing layer cannot be sealed. However, if the temperature of heat sealing is too high, it is easy to damage the heat sealing material at the welding edge, and melt extrusion produces the phenomenon of "root cutting", which greatly reduces the heat sealing strength of the seal and the impact resistance of the composite bag. In the actual aluminum foil bag making bag heat sealing process, the pressure of the heat sealing tool is often adjusted by a rotatable spring.

For light and thin packaging bags, the heat sealing pressure should reach at least 2kg/cm², and it will increase accordingly with the increase of the total thickness of the composite film; If the heat sealing pressure is insufficient, it is difficult to achieve fusion between the two films, which will lead to poor local heat sealing or difficult to eliminate the bubbles caught in the middle of the weld, resulting in virtual welding.