Gravity casting mold means that in order to obtain the structural shape of the part, the structural shape of the part is prefabricated using other easy-to-form materials, and then the mold is placed in the sand mold to form a cavity in the sand mold with the same size as the part structure, and then the liquid Pour it into the cavity, and after the liquid cools and solidifies, the part with the same shape and structure as the mold can be formed.
Due to the complexity of the casting shape, the aluminum alloy gravity casting molds are also different. Even for the same part, different casting processes are used, and the mold forms are often different, but in any case, the aluminum alloy gravity casting molds still have their commonalities.
First, a suitable casting process must be selected. The quality of the casting process is directly related to the quality of the casting and the output of the process. Some domestic mold manufacturers have begun to use solidification simulation to assist the design of the casting process.
Through the computer simulation of the filling and solidification process, it is of great significance to find out the thermal connection parts that are prone to casting defects and overcome them.
Secondly, the mold must have good heat capacity. Thick mold bases and modules that meet the requirements are not only an effective guarantee for the life of the mold, but also play a very important role in the adjustment of the temperature field during the continuous operation of the mold.
In order to reduce costs and save materials, some mold factories blindly reduce the effective thickness of the mold to achieve the purpose of reducing weight, but they do not know that this not only greatly reduces the service life of the mold, but also makes the casting easily deformed and affects the dimensional accuracy of the casting. .This will lead to the scrapping of castings in batches, causing losses to the foundry, and even seriously damaging the mold factory's own reputation.
Third, the mold must have a more reliable cooling system and air extraction system. Through cooling, not only can labor productivity be effectively improved, but also the temperature field of the casting can be adjusted, the cooling rate of the casting can be controlled, and the internal structure and grain size of the casting can be affected. .The purpose of effectively controlling the mechanical properties of castings.
As the name suggests, air extraction is to manually discharge the gas inside the cavity to the outside of the cavity to reduce the possibility of porosity-like defects in the casting. At the same time, by adding vent plugs, the mold temperature can also be adjusted in a small range, which is very effective in preventing and It plays an important role in overcoming the cracking and settlement of aluminum alloys.
Fourth, there must be a mold positioning device that matches the casting machine and a convenient mold installation system. The positioning device is not only the key to ensure the size of the casting and reduce the cut and burr, but also the key to ensure the normal operation of the casting machine. It can be said that if the mold has no Good positioning device, there will be no qualified castings.
The mold must be easy to install and disassemble, because aluminum alloy gt; aluminum alloy gravity casting, gravity casting mold must be removed regularly to repaint and repair the mold. If the disassembly is inconvenient, it will inevitably increase the labor intensity of workers and take up more labor time, reducing yield and efficiency.
