Temperature control for injection molding
Now the use of injection molded parts products is very much, the use of injection molded parts products when the quality requirements are very high, because inferior injection molded parts on the use of the impact is relatively large, so in the choice of need to pay attention. The quality of injection molded parts depends largely on the processing technology, and each step should be strictly controlled during processing, but bubbles will appear in the processing of injection molded parts, which is not up to standard, so let's take a look at the solution to bubbles in injection molded parts processing.
1. When the wall thickness of the product is large, the cooling speed of the outer surface is faster than that of the central part, therefore, as the cooling progresses, the resin in the center expands to the surface while shrinking, so that the central part is not filled enough. This condition is called vacuum bubbles. Solution: a) According to the wall thickness, determine the reasonable gate and gate size. Generally, the gate height should be 50%~60% of the wall thickness of the product. b) Until the gate is sealed, leave the corresponding supplementary injection material. C) The injection time should be slightly longer than the gate sealing time. d) Reduce the injection speed and increase the injection pressure, e) Use materials with high melt viscosity grades.
2. The main methods for solving bubbles caused by the generation of volatile gases are: a) Fully pre-drying. b) Reduce the resin temperature to avoid the generation of decomposition gas.
3. The bubbles caused by poor fluidity can be solved by increasing the temperature of the resin and mold and increasing the injection speed.
After the introduction of the above article, we learned that the bubbles in the processing of injection molded parts are divided into causes, and only after understanding the specific reasons can we make a solution, as long as the method is correct, you can well solve the problem of bubbles in injection molding parts processing, and it will not affect the quality of injection parts.
Guangzhou Ideal Plastic injection molding parts are widely used in processing, and play a very important role in plastic products. It itself has a lot of advantages, very popular in the processing industry, everyone should now be relatively new to injection molding parts processing, not particularly understand how it is processed, and what kind of requirements does it have when processing?
1. Processing in accordance with the confirmed drawings or written documents, can not change the material, shape, thickness and other changes affecting the strength at will, fluoroplastic injection parts in principle to choose materials that require good toughness, wear resistance, cheap price, and some strength;
2. When the sheet metal or machined material products are replaced with fluoroplastic injection parts, in principle, the thickness of the plastic product will increase, and the specific design thickness depends on the product structure and function;
3. All parts that cannot be formed at one time and need to be bonded are required to be firm, flat, and the end is aligned, without the hidden danger of loosening;
Nowadays, plastic products are very common in life, because people use more and more plastic products, and there are many types of plastic products, which have been widely used. The quality of plastic products depends on the control of processing, and the impact of processing on plastic products is relatively large, especially in injection molding processing is temperature control, which is a very important and difficult step, so special attention is required. Now let's take a look at the temperature control of injection molding processing.
1. The mold filling process adopts one-dimensional heat conduction, and the corresponding cooling is also one-dimensional cooling.
2. After the high-temperature fluid enters, the specific heat capacity and its own thermal conductivity of the molded product remain unchanged.
3. In the process of product molding, abrasives and plastic parts are in a constant temperature field.
4. In a constant temperature field, when the core temperature is equal to the temperature at the time of thermal deformation of the plastic, the entire cooling cycle ends. This also shows that the upper and lower limit points have two functions. According to different injection molding requirements, the temperature of its upper and lower limits is also different, so in many cases it is necessary to analyze specific problems.