30 casting samples of cylinder block were selected. The pouring information was counted, including the casting mass (unit: kg), pouring time (unit: s), average head (unit: mm), sprue area (unit: cm2), cross runner area (unit: cm2), runner area (unit: cm2), etc. Determine the type of gating system, calculate and analyze the process parameters of gating system.
According to the different position of molten iron introduction, the pouring methods of cylinder body iron castings are generally divided into bottom pouring, middle pouring and step pouring, as shown in Fig. 1.
It can be seen from the case that the introduction of small-sized castings accounts for the lowest proportion in the bottom casting, and the proportion of the introduction of small-sized castings in the cylinder block is the lowest, accounting for 13% of the application range of the small-sized castings, and the proportion of the introduction of small-sized castings in the cylinder block is the lowest, and the proportion of the introduction of small-sized castings in the cylinder block is the lowest.
According to the proportion of cross-sectional area of each component in gating system, gating system can be divided into four types: closed, open, semi closed and closed open. The purpose of determining the cross-section area of each component of gating system is to ensure the completion of mold filling of cylinder body iron castings within a predetermined time, and effectively control the flow state of liquid metal in the filling process, such as flow rate, flow rate, etc., to ensure the smooth and clean filling process. The section area ratio of each component in gating system and the statistical distribution of pouring type of cast iron production samples of cylinder block are shown in Fig. 2.
It can be seen from Figure 2 that in the casting process of cylinder block iron castings, closed gating system is not used, and open gating system is rarely used, accounting for only 10%. Semi closed and closed open gating systems are widely used, accounting for 43.3% and 46.4% respectively.
The application range of different types of gating system is based on the casting quality. In small cylinder castings, open gating system can be used; for small and medium-sized cylinder blocks, semi closed or closed open pouring systems are generally used; while in the production process of large cylinder castings, semi closed gating systems are mostly used. The mass distribution of different pouring types.