Customized PET bottle stretch blow molding equipment

Customized PET bottle stretch blow molding equipment

For some PET bottles with large quantities, special shapes and specifications, and PET bottles with special applications, special molding equipment needs to be developed to meet user needs and reduce the manufacturing cost of user products.

1 Development of PET special bottle type stretch blow molding machine

Dedicated to the production of PET complex-shaped packaging bottles and flat containers. The conveying system for preforms and finished bottles (through the bottleneck) is forward conveying to keep their appearance smooth. Radiant heating creates a precise temperature slope that changes with the heating zone on the preform, ensuring uniform material distribution. Selective heating of certain preform areas changes the temperature distribution in targeted areas that coincide with the shape of the mold cavity. Areas with the highest temperatures are stretched first, and then the bottles are formed toward areas with relatively lower temperatures. The special conveying system ensures that the position of the preform in the mold is consistent with the heating direction and packaging shape. The bottle blowing process is optimized to ensure uniform material distribution in flat bottles or complex-shaped containers while reducing bottle weight. Molds can reproduce engravings or other decorations required for highly artistic packaging. Depending on the shape of the flat bottles, the bottle conveyor system adjusts the position of the flat bottles on the bottle outlet conveyor. Productivity is increased through preform loading adapted to the special bottlenecks used in the cosmetics industry. Special bottle necks, such as spray bottle necks, can be stretched relative to the shape of the bottle itself. Switchable from pH device configuration to configuration for still or carbonated beverages and vice versa without major mechanical modifications.

2 Development of PET hot-fill bottle stretch-blow molding equipment

The PET hot-fill bottle application market has suddenly emerged, providing broad development space for PET hot-fill stretch-blow molding equipment. PET bottles with hot filling temperatures of 85 to 90°C have become the fastest growing variety of plastic beverage bottles. The use of PET beer packaging bottles must withstand 62 to 67°C.

Key points in the design of hot-filling preforms: The bottleneck crystallization technology of hot-filling PET bottles is the key. In order to optimize the hot-filling performance of the bottle, the heat-setting process requires special design of the preforms and bottles. The appearance of the preforms must be Specifically designed to achieve an optimal biaxial stretch ratio, thereby reducing package weight while reducing residual residual stress. Solutions to improve the bottle neck heat setting strength of preforms: thicken the preform mouth, embed heat-resistant or crystallized billet mouth. Cosmetic packaging bottle manufacturer

Key points in the development of stretch blow molding equipment for PET hot-fill bottles. Performance requirements for hot-fill bottles: The bottle can withstand a filling temperature of 94°C. During bottle blowing, storage and filling, the filling temperature it can withstand is 88°C. Pasteurization bottles used to hold non-carbonated liquids can last for 10 minutes at a temperature of 75°C. In order to meet the requirements of hot filling, the equipment must provide very precise heat treatment of the preform and sufficient available heat energy to reasonably distribute the material and ensure the crystallinity of the bottle mouth. The preform heating and mold temperature control accuracy is within plus or minus 1°C. Thermal oil is the heating carrier for mold temperature. The machine precisely controls the stretching speed to ensure product consistency. The preform mouth should not be overheated in the heating drying tunnel (rotating shaft and special protection device). During bottle blowing, the inside and outside of the bottle neck are in a state of equal pressure (hood mouthpiece) to better protect the preform mouth. Cooling air should be injected into the bottle before demoulding to ensure thermal stability of the bottle and achieve correct demoulding of the bottle to ensure a high-quality appearance. Heat setting involves increasing the heating temperature of the preform and extending the contact time between the bottle and the hot film.