Mould temperature control of the Hot Pressing Grouting Mold
In the process of injection molding, the control mode temperature plays an important role in the smooth implementation of molding production and ensuring the quality of forming parts. This is not only a high standard for the design and manufacture of mould temperature, but also some effective methods to assist the mould temperature control system to achieve accurate and stable mode temperature control. To this end, the author brought in the application of the injection molding engineer of honggren plastic hot pressed grouting mould factory to the use of mold temperature control of "hot pressure grouting mold".
HR: why do the temperature control during injection molding process? If the temperature control of the hot-pressed grouting mold is not good, what adverse effects will be caused to the injection molding production?
The temperature of the Hot Pressing Grouting Mold refers to the surface temperature of the cavity surface. It has a great influence on the appearance quality and internal performance of the products. If the temperature of the hot-pressed grouting molds is too low, on the one hand, the plastic melt cooling becomes faster, the solidification layer thickness increases, the melt viscosity also increases, causing the forming pressure to become larger and the forming is relatively difficult. On the other hand, the flow of plastic melt is not smooth and easy to flow, the contour of the products is not smooth, while the length and sharpness of the welding marks are enlarged, and the appearance quality of the products decreases. Thermal pressure grouting mold temperature can't is too high, too high will make longer cooling time and the production efficiency drop, product shrinkage rate increase, especially of crystalline plastics shrinkage rate than an amorphous plastics to increase more.
Therefore, in order to ensure product quality and production efficiency, give attention to two or morethings should appropriately increase the mold temperature, hot pressing grouting in order to increase the length of the melt flow, improve the product surface bright and clean degree, crystallinity and density, decreasing internal stress and the molding pressure. At the same time, because of hot-pressing temperature before and after grouting the mould deformation has a great influence on products, hot pressing grouting mould temperature should be equal as far as possible, before and after the greatest difference should not exceed 10 ℃. When the temperature of the Hot Pressing Grouting Mold (runner temperature) rises, it can avoid the small shrinkage cavity in the center of the cold runner. Other technological methods such as adding padding, changing the position of pressure, increasing pressure pressure and pressure protection time, Hot Pressing Grouting Mold and changing the temperature of the cylinder, can not improve the shrinkage of the center of the cold channel. This also shows that the temperature control of the mould temperature is very important for improving the quality of products.
The heated molten plastic material is injected into the hot pressed grouting mould cavity and then becomes the product by cooling the mold. The temperature of the hot-pressed grouting mold should be properly controlled - not too low or too high. This is because: low ambient temperature in winter, cause mould is very cool, hot pressing grouting without heating hot pressing mould of the grouting, to the right temperature, molten plastic materials is still not fully into the mold cavity, hot pressing grouting has cooled, cause waste or defective product. But neither can hot pressing grouting mold temperature is too high, high hot-pressing mold temperature can make the injected into the hot pressing grouting slowly cooling of plastic raw materials in the mold cavity, which affects the efficiency of work. However, Hot Pressing Grouting Mold if the plastic material is not completely cooled, the product will be removed, the product will be deformed, it will not be able to meet the requirements of the size of the product drawing, and the product will have a large burr. Therefore need to mold for cooling, hot pressing grouting to make into the cavity of the plastic materials can quickly cooling molding, this can speed up the working efficiency, Hot Pressing Grouting Mold and produce products to become qualified products.