Unwinding: The roll of raw material (such as plastic film, non-woven fabric, etc.) is unwound by an unwinding device and fed into the processing area of the bag-making machine. During unwinding, the material tension must be kept stable to avoid stretching or wrinkling.
Folding or Lamination: Depending on the type of bag (e.g., flat bag, vest bag, three-side seal bag, etc.), the material may need to be folded or laminated with other materials. For example, vest bags require folding the material in half and heat-sealing both sides, while three-side seal bags require heat-sealing on all three sides.
Heat Sealing: The edges of the material are sealed using a heating device (such as a heat-sealing knife or ultrasonic sealing). The heat-sealing temperature, pressure, and time need to be adjusted according to the thickness and type of material to ensure a strong and aesthetically pleasing seal. For example, the sealing temperature for PE material is typically between 120-180℃.
Cutting: The heat-sealed material is cut into individual bags to a preset length. Cutting methods can be hot-cut (using a heated blade) or cold-cut (using a mechanical blade). Hot cutting is suitable for plastic films, while cold cutting is suitable for materials such as non-woven fabrics.
Rolling or stacking: The cut bags are wound up by a winding device or stacked by a stacking device for subsequent packaging and transportation.
