Technical Requirements of Die Casting Mold External Shape and Installation Position
Die casting mold is a tool for producing parts with die casting process. Die casting dies are complex, expensive and long cycle parts. To reduce the production cost of die casting, ensure the dimensional accuracy, good surface quality and service life of parts, reasonably design, manufacture and use die casting dies. This article will discuss the technical requirements on external shape and installation position of die casting mold.
The external shape of the die casting mold determines its size and shape, which directly affects the mechanical properties, dimensional accuracy, surface state and service life of the casting. The die casting die should have a reasonable shape, which is conducive to the smooth flow of molten metal, reduce the amount of molten metal flowing, improve casting quality and reduce energy consumption. The common design elements of die casting mold in external form include pouring system, gating system and exhaust system.
The pouring system generally includes pouring cup, pouring hole, pouring filter, runner and other components, which is an important part that affects the smoothness and stability of molten metal flow. The size of the pouring cup should meet the requirements of easy pouring and prevent the plastic situation of molten metal inside the pouring cup with cold air. The edge of the pouring hole should be designed to help the slow sinking of the molten metal level, separate the impurities of the molten metal, and keep the molten metal pool during the filling process to reduce the pressure loss. In addition, the design and size of the filter should also meet the requirements of pressure loss, shape and easy access.
Gating system is an important component of die casting die. Its design should ensure good filling performance of the melt, reduce pressure loss and ensure uniform temperature of the melt. For example, when the thin-walled pressure column is die-cast, a sub-gate is adopted to form a local restriction for die-casting pressure to improve the filling performance of the melt.
The exhaust system is a component that allows the air in the molten metal hole to flow out, which plays a role in ensuring the uniformity of shrinkage cavity pressure and flow movement of the melt, improving the quality of the casting, and preventing the gas from damaging the mold. The most commonly used exhaust system is a negative pressure exhaust system, which includes a vent structure and a vacuuming port. The vent should meet the requirements for the number, position, size and shape of the holes, good exhaust performance and small pressure loss.
The die casting die needs to pass the test of loading and unloading, maintenance, positioning and clamping in the actual application. The external shape of the die casting die refers to the overall shape design required by the installation position in the die casting machine. Including feeding hole, feeding hole degree, feeding hole location, feeding hole support, ejector pin hole, product hole position and degree, etc., so that the product has accurate punching and positioning, to ensure the accuracy of its size, shape and appearance quality.
In short, the external shape of the die casting die should meet the requirements of casting quality, service life and the external form of the product, such as pouring system, gating system, thermocouples and exhaust system. In addition, it should also consider the factors of production cost, installation accuracy, loading and unloading, maintenance, positioning and other practical conditions as well as the development trend of die-casting process.
