From the design drawings to the production of finished container liners, the production process involves 10 steps (excluding special container liner products): raw materials, filament drawing, weaving, coating, cutting, sewing, inspection, sorting, packaging, and warehousing. Among these processes, filament drawing, weaving, coating, and cutting are the main points causing losses.
1. The filament drawing process is one of the processes with the highest consumption in container liner production, with four stages causing losses: During melt extrusion to form a film, there are non-film-forming plastic sheets and blocks; during cooling and cutting the film, there are hard edges on both sides; the formed monofilaments are sucked into the waste filament box until they are wound into the pipe; and the consumption of filter screens is eliminated each time different specifications, varieties, and colors are changed.
2. The weaving process also has relatively high consumption in the production of container liners, with three steps generating losses. The monofilament bobbins rotate on the warp beam and need to be arranged in an orderly manner. When threading the bobbin, lint, loose threads, and dirty threads are generated; when the weft yarn package enters the circularly moving shuttle, lint, loose threads, and dirty threads are generated. The consumption of single filaments and single sheets in the front and rear transfer processes occurs each time different woven fabric specifications and varieties are changed.
3. The coating process is the second process with high unit consumption, involving three sub-processes. After coating, the raw edges of the single woven fabric need to be trimmed; during the melt extrusion of the raw material, there is high-temperature molten plastic material that does not form a film; the consumption of single woven fabric sheets and composite woven fabrics in the front and rear transfer processes occurs each time different widths and unit weight specifications and varieties are changed.
4. The cutting process is one of the three processes with high unit consumption. The consumption per unit varies depending on the shape of the inlet and outlet. For example, the conical material outlet connected to the inner lining of the container wastes more. It is also affected by the length of the material outlet. The longer the material outlet, the greater the consumption per unit; for the bag body consumption, the bag cap on the bag body is connected to the feeding port. The larger the material port size, the more wasteful the bag cover fabric needs to be. Similarly, the size of the bottom cover and the feed port are also factors affecting the unit consumption.
5. The sewing thread consumption used in the assembly of container liner bags is extremely small and can be ignored.