The production of a plastic bag

                                                                                                              The production of a plastic bag

一、 Blown film

The entire process of blown film mainly includes the following steps:

Heating and melting of plastic particles: adding plastic particles into an extruder and melting them through heating. ‌

Extrusion molding: Molten plastic is passed through the die at the front end of the extruder to form a cylindrical tube blank. ‌

Blowing: Inject high-pressure air inside the tube blank to blow it to the desired thickness. During this process, there will be elongation in both the longitudinal and transverse directions, forming bubbles. ‌

Cooling and shaping: Use an outer air ring to cool the bubble tube, and sometimes add internal cooling to ensure the shape and size stability of the film. ‌

Flattening and Pulling: The bubble tube is flattened and pulled by a guide clamp and a pulling clamp roller to maintain the required inflation pressure and prevent air leakage. ‌

Roll up: Finally, the flattened film enters the winding device and is rolled up into a roll.

二、 Printing

1.Pre press preparation: Select the appropriate printing machine and printing plate, process the printing plate, and mix pigments and inks.

2.Printing machine settings: Adjust the speed, temperature, pressure, and other parameters of the printing machine according to the specifications and requirements of the plastic bag. Printing: Place the plastic bag on the printing machine and 3.transfer the pigment ink through a drum or screen to cover the plastic bag.

4.Drying treatment: Use ultraviolet radiation to dry the printed plastic bag to ensure ink fixation. Post processing: Cut and roll the printed plastic bags to meet their usage requirements.

三、 Cut the bag

Ensure that the equipment is in a safe state, the power connection is normal, and all components are not damaged or loose.

Check if the heat sealing blade and cutting blade are sharp, and replace them if necessary.

Prepare the packaging materials to be sealed and cut, ensuring that their quality and size meet the equipment requirements. ‌

2.Adjust device parameters:

Adjust the heat sealing temperature and speed according to the type and thickness of the packaging material. The heat sealing temperature should be slightly higher than the melting point of the material, and the speed should be adjusted according to actual needs.

Adjust the position and speed of the feeding device to ensure that the film or paper can be smoothly and accurately fed into the forming area. ‌

3.Start operation:

Place the packaging material at the feeding port, ensuring that the material is flat and wrinkle free.

Start the device and begin the sealing and cutting operation. Pay close attention to the operation status of the equipment to ensure the quality of heat sealing and cutting.

Adjust the temperature, pressure, and time parameters of the heat sealing knife to ensure that the heat sealing line is firm and aesthetically pleasing. ‌

4.Inspection and adjustment:

If poor heat sealing or uneven cutting is found, the machine should be stopped immediately for inspection. It may be due to insufficient heat sealing temperature, excessive speed, or poor material quality.

Adjust equipment parameters or replace materials according to specific circumstances. ‌

5.Complete operation: Take out the finished product from the discharge port and stack it neatly. Maintain the cleanliness and orderliness of the work area.

Clean the surface and interior of the equipment to remove residues and dirt.

Pay special attention to cleaning the heat sealing blades and cutting blades, keeping them sharp and clean. Check if all components of the equipment are intact, and replace them promptly if there is any damage or wear.