Pet Bottle Preform Machine

ZOWEITE® PET Bottle Preform Machine is an optimized injection molding machine for PET injection molding. It is the important PET equipment in the manufacturing process of PET bottle blank. Even in the whole PET Bottle Preform Machine are specially designed according to the characteristics of PET materials. Professional injection molding unit( screw, cylinder, heating, etc.), clamping unit (clamping plate, clamping force, ejector, etc.) and machine frame and control device of PET Bottle Preform Machine

What is difference between the injection device and clamping device of PET bottle preform machine and ordinary injection molding machine?

Injection device.

Special injection molding machine screw of PET bottle preform machine: compared with ordinary injection molding machine , the diameter of the screw is larger, the length diameter ratio of the screw is mostly 24, and the melting line and color mixing are better.

Screw with low shear and low compression ration are the most popular products. Screw and can bodies are constructed to avoid bending.

Components and nozzles: the mixing components are more complex, optimized and the color is more conspicuous. The nozzle hole for PET material injection is relatively large.

More energy saving and precision: the infrared heating ring of PET bottle preform machine is an energy saving standard configuration with or more precision temperature PIC control.

Clamp device

The optimized clamping force and change-over switch make the price more competitive and have a larger die opening stroke.

Increase the gap between the pressing plate and the tie bar to form a large cavity. The ejection stroke and ejection force are increased.

Fully closed safety door and safety office, with higher safety quality and short cycle.

What should be paid attention to during injection molding of PET bottle preform machine?

Treatment of plastics: because PET macromolecules container lipid groups and have certain hydrophilicity, the pallets are sensitive to water a high temperature. When the moisture content exceeds the limit, the molecular weight of PET decreases during processing, and the products are colored and brittle. Therefore, the materials must be dried before processing. The drying temperature is 150℃ for more than 4 hours.

Selection of PET bottle preform machine

Due to the short stabilization time after the melting point and high melting point of PET, an injection system with more temperature control sections and less self friction heat generation during plasticization shall be selected, and the actual weight of the product ( water containing

mouth material) shall not be less than 2/3 of the injection volume of PET bottle preform machine

Mold the gate design

PET preform is generally formed by hot runner mold. It is best to have a heat insulation plate between the mold and the PET bottle preform machine template, with a thickness of about 12 mm, and the heat insulation plate must be able to withstand high pressure, the exhaust must be sufficient to avoid local overheating or fragmentation, but the depth of the exhaust port shall not exceed 0.03mm, otherwise it is easy to produce flash.

The melt temperature of PET bottle preform machine

It can be measured by air shooting method,. 270-295℃, and the reinforced GF-PET can be set to 290-315℃。

Injection rate

Generally, the injection rate should be fast to prevent premature solidification during injection. However too fast and high shear rate make the material fragile. The ejection is usually completed in 4 seconds.

Back pressure

The lower the better to avoid wear. Generally not more than 100bar. Usually not required.

Retention time

Do not use too long residence time to prevent molecular weight reduction. Try to avoid temperatures above 300℃. If the shutdown is less

than 15 mins. Only air shooting is required; If it exceeds 15 mins, clean it with viscosity PE temperature until it is started again.

Precautions

The recycled materials shall not be too large, otherwise it is easy to “bridge” at the blanking place and after the plasticization.

If the mold temperature is not well controlled or the material temperature is not properly controlled, it is easy to produce “white fog”and opacity. The mold temperature is low and uniform the cooling speed is fast, and the product is transparent if there is less crystallization.

ZOWEITE® have 30 years experience in injection molding machine industry and our factory got ISO /SGS certificate. We design the PET bottle preform machine, which has the function of optimization manufacturing process management, production management and quality control system. We can provide customer with Turn-key project, including fast ans stable PET bottle preform machine with special screws, auxiliary machine, mold and factory drawings designed according to customers. ZOWEITE PET bottle preform machine is widely used in different molding products, such as water bottle pet preform, wide mouth preforms, 3 gallon and 5 gallon bucket preforms, etc. The special screw makes the products produced by the PET bottle preform machine more transparent and of better quality.