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There are several problems in the use of plunger injection machines for plastic molds. More and more mold factories use plunger injection machines in plastic molds. However, although the plunger injection machine has a simple layout, it has the following three. Questions: 1. Plasticization unevenness The so-called plasticization refers to the process of plastics softening the uniform melt with excellent plasticity by heating and mechanical work in the material, and the movement of plastic in the material of the plunger injection machine. Only rely on the advancement of the plunger. There is almost no mixing effect. Therefore, the outer temperature of the plastic and the barrel and the shunt touch are higher. Due to the poor thermal conductivity of the plastic, the inner layer is not melted when the outer plastic is melted. When the inner layer of the plastic is melted, the outer layer can be degraded by heat for a long time at a high temperature,

Which is more outstanding for the heat-sensitive plastic, the plasticization is not uniform, and the internal stress of the plastic product is large. 2, injection pressure loss large plunger injection machine nominal injection pressure, although high, but because of the pressure at the injection of the plunger, some pressure is required to compact the solid plastic and overcome the frictional resistance between the plastic and the inner wall of the barrel, so The effective pressure transmitted to the cavity cap mould factory is only about 30-50% of the original. 3, the progress of the injection volume is limited because the maximum injection volume of the injection machine depends on the plasticizing ability of the barrel and the diameter and stroke of the plunger, and the plasticization can be related to the heated area of ​​the plastic.

To improve the plasticizing ability, the primary basis is to increase the diameter and length of the material, which will make the plasticization more uneven, and the plastics can be more degraded, so the plasticization can be improved. In addition, during the plunger injection molding, the plastic activity is not ambivalent, and the finishing of the barrel is also difficult. Therefore, the amount of plunger injection is not large, and is usually only 60% or less.