What is Preform?

A preform is a semi-finished product made from PET (Polyethylene Terephthalate),
primarily used in the production of PET bottles. As the initial step in the bottle
manufacturing process, preforms are created through the injection molding method and
later transformed into the final product shape through blow molding. Structurally
resembling a tube or test tube, a preform has a finished neck (including the diameter and
threads), which facilitates processing in blow molding machines.

Preform Production Process

Preforms are manufactured with precision and in compliance with industry standards using
advanced production technologies. The process involves the following steps:

Raw Material Preparation:

• PET granules (raw material) are dried to remove moisture, which is essential
  to preserve material properties and prevent defects during production.

Injection Molding:

• The dried PET granules are melted at high temperatures in an injection
  molding machine.
• The molten PET is injected into a preform mold, which determines the
  weight, size, neck diameter, and wall thickness of the preform.
• During this stage, the neck section is finalized, while the tubular body is
  designed for shaping during the blow molding process.

Cooling and Solidification:

• The preform in the mold is rapidly cooled and solidified through internal
  cooling channels. Cooling time is a critical parameter that influences production
  speed and preform quality.

Storage:

• The completed preforms are prepared for transportation to blow molding
  machines or stored for later use.

Technical Features of Preforms

Preforms determine the quality, durability, and design standards of the final product. Key
characteristics include:

Weight and Volume:

• Preforms are manufactured in various weights corresponding to the capacity
  of the final bottle (e.g., 0.33 L, 1 L, 1.5 L). Larger bottles require heavier preforms.

Neck Diameter:

• The neck section is designed to be compatible with the caps of the final
  bottle. Common neck diameters include 28 mm, 30 mm, and 38 mm, ensuring
  product sealing and cap compatibility.

Wall Thickness:

• The wall thickness of the preform affects flexibility during the blow molding
  process and the durability of the final product. For instance, preforms for carbonated
  beverages are often thicker.

Transparency and Color:

• Preforms can be clear or produced in specific colors. Color pigments are
  added during the production process to meet aesthetic and functional requirements.

Material Quality:

• Preforms are made from recyclable PET material, which is environmentally
  sustainable.

Transforming Preforms into Final Products

Preforms are shaped into their final form through blow molding, which involves the
following steps:

Heating:

• The preform is heated to a specific temperature before being placed in the
  blow molding machine. This step makes the preform pliable for shaping.

Blowing:

• The heated preform is placed in a mold that determines the size and design
  of the final bottle or container.
• High-pressure air is injected into the preform, expanding it to fit the mold’s
  shape.

Cooling:

• After the blowing process, the product is cooled within the mold to finalize its
  shape.

Applications of Preforms

Preforms are widely used across various industries due to the durability, lightweight
nature, and processability of PET material:

Food and Beverage Packaging:

Used for packaging water, carbonated drinks, juices, and dairy products.

Cosmetic and Cleaning Products:

Commonly used for bottles of shampoo, detergents, and liquid soaps.

Industrial Use:

Suitable for packaging motor oils, chemicals, and other industrial liquids.

Quality and Advantages of Preforms in Production

The correct design and production of preforms directly impact the performance of the final
product. High-quality preforms offer the following advantages:

• Durability and Lightness: Ensures products are easy to handle during transport
  and by end-users.
• Aesthetic Appeal and Transparency: Improves the appearance of the bottle and
  allows clear visibility of its contents.
• Recyclability: PET’s eco-friendly nature supports sustainability initiatives.

Preforms play a crucial role in the production of PET bottles and other packaging
solutions. The precision of the injection molds and the technical properties of the preform
influence both production efficiency and the quality of the final product. As a fundamental
component of the PET packaging industry, preforms meet the requirements for food safety,
aesthetic design, and environmental sustainability.