Plastic pipe extrusion, we often encounter a series of problems. In addition to possible plastic tube surface cracks will appear, black lines, moire phenomenon than we may also encounter inside a plastic tube produced a bubble, then under what circumstances, will produce plastic tube inside the bubble it ?
Plastic pipe inside bubbles, in general, is related to the moisture content of resins and additives. If the water is too high, then the plastic tube pipe bubbles will be porous.
Attention to this problem, we just need the moisture content of raw materials is controlled within a reasonable range can be, general raw material moisture content is controlled within 0.3% -0.5% range. Injection molding machine in a high speed mixer can exclude only the water portion of the raw materials compounded when, at the same time when we store the raw material for stacking the choice of location is to be noted that, especially in the rainy season should pay attention to prevent material moisture. Damp PVC resin can not directly fire baked, in order to avoid thermal decomposition of the resin, the baking, if desired, add some stabilizer in advance. After high speed mixing materials in storage after the rainy days, it must first be used only after drying.Construction of vertical injection molding machine before th
If we find the injection molding machine plastic tube inside the bubble, then the die temperature should be slightly lower at the point of extrusion speed can not too fast, in order to eliminate air bubbles inside the plastic tube. And, while cooling in shape when flash is not suitable for rapid cooling, in that case, plastic pipe will be prone to bubbles.
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