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(Headquarters)Jiujiutongxin Industrial Park, Tongle Town, Longgang District, Shenzhen, China


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Blowing Mould Products Will Cause Those Poor Emissions?
Oct 19, 2017

When the container with the same volume is molded, the amount of air to be discharged in the blowing mould is much larger than that of the injection molding die. The volume of air to be discharged in the injection molding die is at most equal to the amount of melt injected into the mold cavity.

And for the blowing mould, the volume of air to be excluded is equal to the volume of the cavity minus the volume of the mold after the fully closed mold has been inflated, where the latter accounts for a large proportion but there is still some air And mold cavity, especially for barrels, fuel tanks and the like large volume blowing moulding products.

To blow 120L vats as an example, the cavity volume is about 145L, fully mold instantly parison has been blown into a volume of about 90L, so that the final stage of inflation (about 2 to 38) discharge about 55L of air The In addition, the pressure in the blowing mould is small (typically less than 1 NPa) compared to the injection molding die. Therefore, the blowing moulding mold exhaust performance requirements are higher (especially the cavity of the mold). In the case of

If the air held between the cavity and the parison can not be discharged completely or as soon as possible, the parison can not be inflated quickly, and after the inflation can not be in good contact with the mold cavity (especially the corners), the surface of the product will appear rough , Dent and other defects, the surface text, the pattern is not clear enough to affect the appearance of the product performance and external shape, especially when the parison will appear when the strip or melt fracture occurs.

Poor exhaust will also extend the product cooling time, reduce its mechanical properties, resulting in uneven distribution of its wall thickness. To this end to improve the blowing mould mold exhaust performance.