Plastic bottle manufacturing process -the step by step guide

How is a plastic bottle made? The raw material is melted by the machine, injection molded into a embryo, and the embryo is reheated and blown to form a bottle.According to demand, we can produce plastic bottles of different materials and bottle shapes.

1.Raw material suction, conveying, melting system
All our materials used for any bottle and jar are 100% new and food grade.
the PET resin chips are all kept in the jumbo bags, there is an Vacuum Feeder pipe linked between the material and injection molding machine. The PET chips will be sent to the feed hopper, then from the hopper, the PET resin chips/pellets will enter the heated barrel, it will be melted by heat and the shearing action of a feed screw to mix it completely.

2.Injection molding stage: tube, PP cover, etc.
The plastic is then injected into multiple-cavity molds where it forms the shape of long, thin tubes. These tubes, called Preforms, usually include the formed necks and threads that will be used to cap the bottles that are yet to come. PET preforms, or pre-forms, are easily shipped to bottling facilities as they are much more compact than fully formed bottles.


3.Tube Reheating and Blow Molding Stages
During the re-heat process, the preforms are loaded into a feeder and run through an unscrambler, which orients the preforms for feeding into the blow molding machine. The preforms are heated by passing by quartz heaters and then enter the mold.
Here, a thin steel rod, called a mandrel, slides into the neck of the preform where it fills the preform with highly pressurized air, and stretch blow molding begins: as a result of the pressurized air, heat, and pressure, the preform is blown and stretched into the mold and forms a bottle shape.

The mold must be cooled relatively quickly, so that that the newly formed component is set properly. Water can be coursed through pipes surrounding the mold, which indirectly cools the mold and plastic. Direct methods include using pressurized air or carbon dioxide directly on the mold and plastic.

4.Plastic bottle generation inspection stage
Once the bottle (or, in continuous manufacturing, bottles) has cooled and set, it is ready to be removed from the mold. If a continuous molding process has been used, the bottles will need to be separated by trimming the plastic in between them. If a non-continuous process has been used, sometimes excess plastic can seep through the mold during manufacturing and will require trimming. After removing the bottle from the mold and removing excess plastic, the plastic bottles are ready for transportation or filling.

After the production is completed, the plastic bottles will be packaged and shipped after passing the manual quality inspection. We can also customize logos, labels and even brand new designs according to customers’ needs.


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