Precautions of Forming for the Bottle Mould
The molded part of the bottle mould is composed of a mold cavity which is formed into a plastic part shape. It is composed of the mold and the mold part. The mold part is usually formed by punch (forming plastic inner shape), concave mold (outer shape of plastic ), Cores, inserts and inserts. Molten plastic from the injection molding machine nozzle into the mold cavity through the mold through the channel called the main channel of the pouring system, gates and cold wells and other components.
In order to make the molten plastic in the mold cavity as soon as possible curing molding, improve production efficiency, some plastic molding, the bottle mould must be cooled, usually in the mold to open a cooling waterway, when the plastic filled cavity and a certain holding time After the water pass through the cold water to cool the mold.
Die-casting mold, blow mold, emblem extrusion die and drawing die can form a bottle mould, must consider the exhaust system, especially for forming large-scale products, precision products and easy decomposition of gas-producing resin is particularly important. The exhaust system can replace the air and material in the mold cavity to escape the gas, to ensure that the high quality parts.
The main sources of the gas in the injection molding mold are the following: the air present in the cavity and the pouring system; the water vapor generated by the evaporation of the water contained in the plastic raw material at high temperature; the gas produced by the decomposition of the plastic at high temperature; The gases produced by the evaporation or chemical reaction of the additives, such as thermosetting plastics, often produce gases due to chemical reactions.
As the closed air resistance in the mold cavity to prevent the flow of molten material, slow down the flow rate, resulting in poor filling phenomenon. Also closed in the mold cavity in the amount of gas remaining in the mold cavity, if not millions of charred will also cause poor filling phenomenon. This situation is most likely to occur when the preparation of a material having a large hygroscopic property is incomplete.
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