Polyethylene terephthalate, commonly known as PET, is one of the most widely used materials in the packaging industry, especially for beverage containers. The 28mm PET preform is a specific type of preform designed to produce bottles with a 28mm neck finish, which is a popular standard in many global markets. Understanding the characteristics and performance of the 28mm PET preform is essential for manufacturers, bottlers, and packaging engineers to ensure the quality and efficiency of their production lines.

A PET preform is a test-tube-shaped piece of PET resin that is later blow-molded into a finished bottle. The 28mm designation refers to the diameter of the neck finish, which influences the type of cap that can be used. This neck size is versatile and widely adopted for various packaging needs, including soft drinks, water, juices, and other liquid products.

The preform itself is a crucial intermediate product because its design directly affects the final bottle’s shape, strength, weight, and sealing integrity. It is manufactured through an injection molding process that melts PET resin pellets and injects the molten material into a mold cavity shaped like a preform.

The 28mm PET preform features a standardized neck finish that accommodates various types of screw caps and closures. This neck finish is designed to ensure a secure seal, preventing leaks and preserving product freshness. The threading on the neck must be precise to guarantee compatibility with caps, ensuring ease of opening and reclosing for consumers.

Different thread profiles are available to meet international standards such as the International Organization for Standardization (ISO) or other regional norms. This adaptability allows manufacturers to supply bottles for diverse markets.

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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