1. Clamping pressure: In principle, it should be greater than the total pressure of the injection mold, based on no burr. 2. Pressure and speed have some of the same relationships in the mold. The purpose is to make the raw material fill all corners of the mold evenly, thoroughly and properly. Too low will cause short shot, shrinkage, too high hair, too full, sticky, burning, easy to mold and high internal stress 3. Speed: The speed of the speed determines the condition of the raw material in the mold runner and the finished product, such as burrs, fullness, scorching, slow shooting, short shot, shrinkage holes, poor bonding, and easy breakage. 4. Temperature: different raw materials, different temperatures, too low solution gel color is not uniform, the internal stress of the finished product increases. If the temperature is too low, the pressurization may be too high, causing the screw to break. If the temperature is too high, the product has burrs, and the temperature difference caused by cooling causes shrinkage. Raw materials will break down, turn yellow, change color, and become brittle. The cooling time becomes longer, the gas is not easy to be discharged, and there is gas. 5. Back pressure: The resistance of the screw to retreat when rotating and feeding is called back pressure. Its function is to make the raw material more dense during transport compression. The air and moisture of the raw material can be discharged from the screw. Sols do not contain gaseous components that affect the surface of the finished product. There will be air bubbles in the lower part and the surface will be silver. High will cause overheating, agglomeration, overflow, long cycle, and the screw will not retreat. At the same time, the application of loosening is also important: when the back pressure is low, some raw materials will be loose, while others will not need to be adjusted according to the various materials. When the back pressure is high, be sure to use loose, pay attention to whether the distance does not trap air. 6. The length of mold temperature and cooling time affects the finished mold, shrinkage rate, dimensional tolerance, surface brightness, cycle, etc., and should be adjusted according to the actual situation. In addition, finished products with thickness such as acrylic and PC must have mold temperature to avoid bubbles and stress.

The process of mold design is generally like this: from the user to the plastic product drawing (which may be two-dimensional or three-dimensional), the mold design engineer considers the appropriate structure according to the type, characteristics and shape of the product. That is, the plastic Pieces can be formed by using what kind of mold structure. In this process, the structural design engineer also needs to select the type, size, gate type, quantity, size, location of the runner and determine the number and size of the runner according to some specific requirements of the product. In addition to being structurally sound, the designed mold is also feasible in terms of casting and cooling systems. Obviously, mold design is very demanding on structural design engineers. He not only has experience in structural design, but also has a lot of knowledge in molding materials and molding processes, or the success or failure of the design depends largely on the experience of the mold designer. Even though the design engineer has good experience in mold design, he still faces many new problems, because the actual product is often kaleidoscopic. Sometimes subtle changes or specific product requirements can make an existing experience unavailable, or even if available, it cannot be verified prior to actual testing. This leads to an important design-correction-redesign feature of the mold design process. How to reduce the number of cycles in the process so that the initial design achieves or approximates the combined result is of great significance in practice. CAE analysis is an ideal tool to solve the above problems. The reason is that the tool is based on a relatively accurate mathematical model and thus can approximate the results of actual production practice. In addition, the computational speed allows multiple gating and cooling systems to be executed before the actual test. Evaluate until optimization, thereby shortening design and manufacturing cycles and improving quality. This article presents some of the issues and practices noted in CAE analysis, with examples. (1) Clear analysis requirements and priorities. The purpose of CAE analysis is different for different products. For appearance parts, injection molding defects that affect appearance such as welding marks are not allowed on the surface; for parts that do not appear, the position of sintering marks is not important, but if the product has a strict assembly relationship, the allowable warpage and deformation amount become the main pursuit The goal. In addition, it is generally required that all items meet the requirements of flow balance and uniform filling. In practice, it is difficult to satisfy multiple requirements at the same time. In most cases, it is mainly to satisfy a major requirement. On this premise, other requirements are met. Therefore, on the basis of clear analysis requirements, it is also necessary to distinguish which are the main requirements of this analysis. After determining the requirements and priorities of the analysis, it is necessary to initially determine which parameters are modified or changed. For example, the main factors affecting the position of the weld marks are the position of the gate and the shape characteristics of the product. Generally, it is not allowed to change the shape of the product; the main factor affecting the warpage deformation is the shape of the product. From a process point of view, the injection pressure is too large. , Too long pressure holding time and uneven cooling will lead to excessive warpage. In addition to the characteristics of the product structure itself, the size of the gate and runner can directly affect the injection pressure in the cavity. The size and arrangement of the cooling channels directly affects the uniformity of cooling. These factors indirectly affect the deformation and warpage of the product. (2) Analysis of product structure characteristics. Using professional CAE analysis software for injection flow simulation requires geometric modeling first. Generally, this process takes a long time. For this reason, the geometric model should be appropriately simplified to shorten the modeling time and improve the calculation efficiency. At present, some CAE software has the function of directly importing the solid model from professional CAD software, and then using the specific neutral extraction tool in the software to extract the neutral surface for calculation, but when the product structure is more complex, it will be generated. many problems. Therefore, it is still important to simplify details that do not significantly affect the computational results.