Casting Process Design

Casting process design involves the process design of the parts themselves, the design of the gating system, the design of the feeding system, the design of the air outlet, the design of the chilling system, the design of the special casting process, etc.

The process design of the part itself involves the design of the machining allowance of the part, the selection of pouring position and parting surface, the selection of casting process parameters, dimensional tolerance, shrinkage rate, draft angle, correction amount, negative parting number, etc.

The gating system is the channel to guide the molten metal into the mold cavity. Whether the gating system is designed reasonably or not has a great influence on the quality of the castings, which is easy to cause various types of casting defects, such as insufficient casting, cold insulation, sand washing, slag inclusion, inclusion, sand inclusion and other casting defects.   The design of gating system includes the selection of gating system type, the selection of gate location and the determination of cross-sectional dimensions of each component of gating system.   In addition, the choice of gating system is also very important, so how can we choose the right gating system?

For mechanized assembly line and mass production, in order to facilitate production and ensure the quality of the casting, the internal runner is generally arranged at the parting surface of the casting mold. According to the casting position of the casting blank and the selection of the parting surface, the internal runner is arranged at the parting surface of the casting mold, which belongs to the "intermediate injection type" casting system.   Liquid metal inevitably contains certain "slag" in the pouring process. In order to improve the slag blocking ability of the pouring system, it is suitable to adopt a "closed" pouring system.

In the casting process, the design of casting process has a great influence on the quality of casting products, but the selection of gating system cannot be ignored.

The design of the feeding system is an engineering technique to reasonably design risers and subsidies to compensate for the shrinkage of the liquid and solidified bodies generated during solidification of the casting to obtain a sound casting.

The air outlet hole is used to discharge the gas in the cavity, improve the filling capacity of the molten metal, remove the supercooled molten metal and scum filled into the cavity first, and can also be used as a sign for observing whether the cavity is full.