A PET preform is essentially a small, molded plastic piece that resembles a test tube or small bottle. It is made through an injection molding process where PET resin is heated, injected into a mold, and cooled into the desired shape. These preforms are then heated again and stretched into their final form (i.e., bottles) using a blow molding process.

The 28mm in the name refers to the neck size of the preform. This size is designed to be compatible with standard bottle caps, commonly found in beverage packaging. The neck dimensions ensure that the preform can be efficiently molded into a functional container once it goes through the stretching and blowing process. The 28mm PET preform is one of the most commonly used sizes in the beverage industry, making it a crucial component in the packaging of beverages across the globe.

Bottle Manufacturing: The most prominent role of 28mm PET preforms is in the manufacturing of plastic bottles. Once the preform is heated and stretched in the blow molding machine, it expands into the shape of a bottle. The 28mm neck size is particularly well-suited for bottles that need to hold carbonated drinks, still beverages, or other liquid products. This size accommodates standard bottle caps, ensuring a secure seal for the contents.

Efficient Production: The use of preforms simplifies and streamlines the manufacturing process for plastic bottles. Instead of molding a full-size bottle directly, manufacturers produce smaller preforms and then blow them into the desired shape. This saves energy, reduces material waste, and improves production efficiency. The 28mm PET preform allows for faster production cycles due to its standardization and compatibility with automated systems.

Product Protection and Preservation: In the beverage industry, it is essential to maintain the quality and integrity of the contents, especially when dealing with carbonated drinks or perishable beverages. The 28mm PET preform, once molded into a bottle, provides an airtight seal, protecting the contents from contaminants, air, and moisture. This ensures that the products remain fresh and safe for consumption, enhancing product shelf life.

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Bottle Mouth Size    Weight in Grams    Reference Capacity    Length（mm）    Number of Cartons    Remark or Note
28mm    16g    350ml-500ml    85    750pieces/Box    Gas Seal
28mm    18g    500-550ml    95    650pieces/Box    Gas Seal
28mm    21g    550-650ml    95    600pieces/Box    Gas Seal
28mm    23g    550-650ml    102    600pieces/Box    Gas Seal
28mm    26g    650ml-750ml    102    600pieces/Box    Gas Seal