Take the valve body as an example to briefly introduce thedesign.
1.Selection of pouring position and parting surface
According to the selection principle of pouring position, the three flange and sealing surface of valve body are important parts. Due to the structural characteristics of the valve body, in order to ensure easy demoulding and quality, the center line of three flange horizontal direction is taken as the parting surface. The position of the flange on both sides of the half face is designed as the pouring position. In this way, the minimum number of mud cores can be ensured and it is also convenient for core setting and inspection.
According to the main dimensions of the casting, please refer to the relevant manual, and determine the machining allowance according to the product size.
Riser design is the key of casting technology. It is the key to ensure the internal quality of castings. It is necessary to ensure that the riser solidifies later than the casting, so that the liquid metal in the riser can fully supply the volume shrinkage during the solidification process of the casting. Firstly, the distribution of hot spot in casting is analyzed. Riser should be set at the thick part of casting, that is, hot spot. For the valve body, the root of the three flange and the sealing ring are hot joint areas. Therefore, risers should be set in these parts.
If both valve bodies are so considered. But there are also some differences. The temperature of molten metal in riser is higher than that in casting when the riser with concealed edge is adopted and the gate passes through the riser. Open top riser is adopted.
Although the riser forms are different, the results are consistent. All of them can ensure the feeding effect of riser, and the calculation method of specific riser is omitted.