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What is the knowledge about (blow molding machine) bottle blanks?

Bottle blowing machine? Large blow molding machine? Bottle blast molds? These products you should know it, today as its suppliers to be introduced here and everyone is the product blowing machine - bottle blanks related knowledge, if you are also similarly troubled by this problem, then the following introduction can certainly help you, read it together.

Blow molding machine bottle blanks, also known as type blanks, is PET granules by injection molding, it requires the proportion of recycled material can not exceed 10%, the number of recycling can not exceed twice. Injection molding of the bottle blanks or reuse after heating the bottle blanks must be cooled for more than 48h, and the use of the bottle blanks can not be stored for more than 6 months, different production dates, especially too long an interval between the bottle blanks can not be mixed, mainly due to the type of raw materials used in the bottle blanks, mixed with the proportion of secondary materials and the residual stress in the bottle blanks due to different, and these factors have a significant impact on the molding process of blowing bottles, should be based on the actual situation Specific treatment.

Because PET has a strong water absorption, so in storage must pay special attention to moisture, and in the processing must be effectively dehumidified before drying, drying conditions are usually 150 ~ 180 ℃ for 4 hours, and to prevent the plastic grain moisture absorption again, must be held at a temperature of 140 ℃ or more, shutdown to prevent plastic yellowing, dehumidification dryer to be cooled to 100 ℃, not dehumidification only insulation.

In addition, PET injection molding if the material temperature is too high, screw shear force is too large or too fast speed are easy to produce acetaldehyde and lead to acidification, usually molding PET bottle acetaldehyde content must be less than 3ppm, bottle embryo before crystallization requires a certain moisture content, generally required in about 1000 ppm, at least 900ppm or more, so the embryo in the injection need to be placed for a period of time and so the moisture content to reach Therefore, we need to wait for a period of time until the water content reaches the required level before crystallization. In the above article, we not only understand the product bottle blanks, but also clearly understand its relationship with the product blow molding machine.