Phenomenon 1: PET bottle preform is opaque
Cause: It may be due to insufficient drying and plasticization of raw materials; Or mixed with other plastics, the purity is not high; Moreover, the material temperature is too low, resulting in the opacity of PET bottle preform.
Solution: Check whether the drying material temperature is too low, or the injection volume is not matched, and ensure that the raw materials are dried at 165 ℃ until the moisture content is less than 0.02%; It must be dried for more than four hours during manufacturing; In addition, try to increase the screw speed.
Phenomenon 2: PET bottle preform cracks at the gate
Cause: This kind of situation is basically caused by the inverted gate and too hot gate area. In addition, the hot runner gate is not concentric with the gate.
Solution: when the gate area is too hot, it is necessary to strengthen the thermal insulation of the gate; In addition, modifying the mold and gate can solve this problem.
Phenomenon 3: The bottle preform bends after demoulding
Cause: Eccentricity of gate hole and uneven cooling will cause the bottle embryo to bend after demoulding.
Solution: when this situation occurs, some measures should be taken. When the gate hole is eccentric, correct the mold; In addition, reducing the pressure maintaining, increasing the injection rate, extending the cooling, cleaning the water channel, and increasing the cooling water pressure and water volume can all solve this bending phenomenon.
Phenomenon 4: The bottle is not fully blown in the vertical direction
Cause: When such a situation occurs, it may be caused by such reasons as too high temperature regulation of the bottle embryo in the part of the bottle embryo that is not satisfied, cold block in the part of the bottle embryo that is not satisfied, insufficient air pressure and air volume, poor exhaust of the bottle blowing mold, too high temperature of the bottle blowing mold, too thin wall of the bottle embryo, and insufficient longitudinal stretching ratio of the bottle.
Solution: Correct the temperature of PET bottle embryo, do not touch the heated embryo body, check whether the cold hard block has touched, increase the air storage pressure, increase the exhaust, add cooling water to the bottle blowing mold, correct the mold, and increase the longitudinal stretching ratio.
Phenomenon 5: Poor vertical bearing capacity of bottle
Cause: When the wall thickness is uneven, the heating temperature of the bottle embryo is too high, and the bottle shape is poor, the vertical bearing capacity of the bottle will be poor.
Solution: To solve this problem, we should improve the uniformity of the bottle wall thickness, the low temperature and high pressure moldiing
