Applications
Polyethylene (PE) Applications: Food wrap, plastic bags (such as drawstring bags), plastic food bags, buckets, and water jugs.
Polyvinyl Chloride (PVC) Applications: Food wrap, plastic shoes and leather products, films, cables, and plastic bags.
Characteristics
Polyethylene (PE): Has a waxy texture, is relatively light compared to other plastics of the same size, and has a certain degree of transparency.
Polyvinyl Chloride (PVC): A hard plastic, commonly used in industrial applications.
Understanding the Production Process and Key Points of Stand-Up Pouches
I. Production Process
Preparation: Install the horizontal heat-sealing knife, bottom heat-sealing knife, and reinforcement heat-sealing knife. Install the punching device.
Thread the film: Set the EPC (Edge Position Control), align the bag edges and patterns.
Adjust the bottom heat-sealing knife: Input the length dimensions, ensure the knife position is aligned, and use the upper knife as the reference for adjustment. Check if the round holes are circular. Set the photoelectric sensor.
Install the bottom film: Adjust it to the center fold. Adjust the bottom film punching.
Adjust the horizontal heat-sealing: Align the heat-sealing knife position with the printed position.
Adjust the reinforcement heat-sealing block: Apply additional pressure at the intersection of four layers.
Adjust the cutting knife and trimming device.
Confirm and adjust the bottom film punching position and bottom heat-sealing position. Confirm and adjust the positions of the horizontal heat-sealing knife and reinforcement heat-sealing block. Confirm the heat-sealing strength and adjust the heat-sealing temperature.
II. Production Key Points
Bottom film tension should not be too high: Excessive tension can deform the round holes on the bottom. The tension should generally be between 0.05–0.2 MPa.
For the first set of heat-sealing knives: Use higher pressure and lower temperature. For the second and third sets, use normal temperature and pressure.
Adjust the spring pressure of the reinforcement heat-sealing block to zero: Allow only the weight of the heat-sealing device to take effect.
Silicone rubber sheets: Generally use sheets with a hardness of 50°. For smaller sealing areas, use sheets with a hardness of 70°.
If the bottom holes are elliptical during heat-sealing: Increase the waiting time by 100 minutes.
Bag-making speed: Generally 50–100 bags per minute.
Introduction to Injection Blow Molding for Preform Manufacturing
Injection blow molding is a two-step process for producing plastic products. In the first step, plastic is injection-molded into a bottomed hollow preform. When the plastic is injected around the core rod in the preform mold, the neck and the preform are formed. In this step, the preform undergoes temperature conditioning. Then, the preform is transferred via the core rod to the blow mold, where air is introduced through the core rod to blow the preform into the shape of the mold. After the bottle is formed, it is transferred to the discharge section.
Advantages of Injection Blow Molding:
No scrap material, precise dimensions, and no secondary processing required for the finished bottle.
The weight accuracy of the finished bottle can be controlled within ±0.1 grams.
The shape of the bottle neck and the precision of the inner and outer surfaces of the bottle can reach ±0.004 inches.
The repeatability of bottle weight and dimensions is suitable for matching and easy integration with filling lines.
Due to biaxial orientation, the transparency and strength of various materials can be improved. In the discharge section, bottles are controlled in a certain direction, allowing for automated inline decoration and filling with minimal operator involvement.
