Precautions for PET preform injection molding

Precautions for PET preform injection molding

1. Before the PET preform is injected, the material needs to be dried for three or four hours to prevent the moisture in the pet from exceeding the limit and affecting the quality of the product.

2. The template and mold of the injection molding machine will need to be separated by a heat shield, and there should be sufficient exhaust during injection molding to prevent the pet preform from breaking.

3. The melt temperature is controlled at 270-295°C, and the air injection method can be used for measurement when the pet preform is injected. the

4. The injection time of pet preforms should be fast, and the time can be controlled within four seconds. the

5. The back pressure is lower than 100bar to prevent wear and tear during the injection molding of pet preforms.

6. The residence time should not be too long. Generally, if the shutdown time does not exceed 15 minutes, it only needs to be treated by air injection, and if it exceeds, the viscosity PE can be used for cleaning.

Injection molding points of plastic preform production plant

Generally, the injection speed should be fast to avoid premature coagulation during injection. But too fast, the high shear rate makes the material brittle. The injection is generally completed within 4 seconds.

Do not use excessively long residence times to avoid molecular weight loss. Try to avoid temperatures above 300°C. If the downtime is less than 15 minutes. It only needs to be treated with air injection; if it exceeds 15 minutes, it should be cleaned with viscosity PE, and the temperature of the barrel should be lowered to PE temperature until it is turned on again.

Due to the short time for PET to stabilize after the melting point and the high melting point, it is necessary to use an injection system with more temperature control sections and less self-friction heat generation during plasticization, and the actual weight of the product (water-containing material) should not be less than machine injection. 2/3 of the amount.

The lower the better to avoid wear and tear. Generally not more than 100bar. Generally do not need to use.

38MM 3start PET Preform

NECK TYPE		WEIGHT	QTY/CTN	CARTON SIZE
38mm 3start PET preform		16g	768	50x38x28
38mm 3start PET preform		18g	768	50x38x28
38mm 3start PET preform		20g	729	50x38x28
38mm 3start PET preform		25g	603	50x38x28
38mm 3start PET preform		28g	486	50x38x28
38mm 3start PET preform		30g	486	50x38x28
38mm 3start PET preform		38g	384	50x38x28
38mm 3start PET preform		42g	384	50x38x28
38mm 3start PET preform		46g	384	47x31x34
38mm 3start PET preform		50g	288	47x31x34
38mm 3start PET preform		52g	288	47x31x34
38mm 3start PET preform		59g	240	47x31x34
38mm 3start PET preform		64g	240	47x31x34
38mm 3start PET preform		70g	230	53x33x33
38mm 3start PET preform		72g	230	47x31x34
38mm 3start PET preform		73g	230	53x33x33
38mm 3start PET preform		75g	200	53x33x33
38mm 3start PET preform		77g	200	47x31x34
38mm 3start PET preform		80g	180	53x33x33
38mm 3start PET preform		85g	180	53x33x33
38mm 3start PET preform		90g	160	53x33x33