Plant for PET-preforms manufacture

The company of "PlastiForm, Ltd." manufactures PET-preforms with the thread in various colours and shades in conformity with the standard PCO 1881. We constantly widen the range of our product mix. Individual products are created for different categories of consumers (taking into consideration the client’s equipment for PET-bottles blowing, inclusive of the requirements for the conformity of the weight and size), continuous high productivity of bottles manufacture is provided.

As of today, our enterprise has at its disposal modern high tech equipment for PET-bottles manufacture and sufficient production space, which enables us to manufacture more than 500 mln. bottles annually.

The manufacturing process of preforms of polyethyleneterephthalate by means of pressure forming conforms to the specification TU 2297-001-69382110-2012. Later containers are made of them by means of blowing. The main consumers of these products are enterprises of the food industry, which makes it mandatory for us as preforms manufacturers to ensure a high cultural level and cleanliness of our own production enterprise. Our raw materials, as well as our end products, are subjected to compulsory hygienic certification.

Preforms manufacture

The fully automatic process consists of the stages as follows:

• Drying of granulated polyethyleneterephthalate;
• Plasticization;
• Injection of polymer melt;
• Cooling and transport of finished products.

The aim of the first stage of PET-preforms manufacture is to bring to a minimum the residue humidity content in the polymer prior to melting (down to the humidity content below 40 ppm, the recommended temperature for efficient drying amounts to 180°C). Raw material is dispensed by portions by means of a vacuum charging device into the bin in such a way, as to keep it continuously full, and is being stirred inside it in a special way (each portion stay time amounts to about six hours). When humidity has been eliminated from the raw material through the filter and cooler into the absorber-dryer, air is again supplied into the bin.

In the second stage of preforms manufacture granulated polymer is fed into the extruder, where it’s molten. Plasticization of granules is carried out by means of the extruder screw conveyor, into which polymer is fed after drying under 180°C. Material feeding is being controlled by temperature sensors, with which all the zones of the extruder are equipped. The lowest admissible level of the melt temperature is recommended, since it ensures short duration cycles and no threat of overheating, admissible level of acetaldehydes and homogeneity of the material.

Consequently polyethyleneterephthalate melt is fed into the mould through the closure unit. A system of hot channels dispenses the melt into a 96-nest mould. There it is exposed to pressure with subsequent opening of the mould and passing preforms over into the cooling plate of the robot. Upon achievement of the required temperature the preforms are shed off into the acceptance container and then onto the conveyor. The conveyor is moving in two directions and is switched over automatically upon filling of the container.

All the technological parameters are regulated on the sensor display.

In the final stage boxes filled with PET-preforms are sent to packing, marked, registered in the system and dispatched to the finished products storehouse.