The closed gating system is adopted, and the proportion is as follows:
ΣA inside: ∑A transverse: ∑A straight = 1:1.3:1.5
The main function of the gating system is to control the filling speed and direction of the melt, distribute the molten metal, adjust the temperature of the molten metal at each part of the axle housing and the solidification sequence of the axle housing. The molten metal of the gating system has a certain feeding effect on the axle housing through the runner. The location and number of runner on the axle housing should be based on the selected solidification sequence or feeding method.
According to the bridge shell parting surface and the shape and structure of the bridge shell, the number of ingates is 1, and the cylindrical ingate is selected. Because of its large modulus and easy cleaning, it can improve the feeding effect of cross runner. The density of zg40mn is 7.8g/cm3. Through calculation, the weight of the axle housing is about 117kg, and the number of ingates is one. For heavy and pouring parts, the area of flow blocking section can be determined by pouring specific speed method, which refers to the weight of molten metal passing through the flow blocking section in unit time. According to the formula, the area of ingate can be designed as follows:
Where:
A-cross sectional area of flow resistance (cm2);
GL – the weight of liquid metal flowing through a resistance section (kg), GL = 108kg;
K-pouring specific speed [kg / (cm2. S)];
T-pouring time (s);
S’ – flow coefficient of molten metal, s’ = 0.8 for high manganese steel;
The runner is the passage from the end of the sprue to the front end of the gate. The runner needs to provide a stable flow of molten metal to buffer the flow rate of molten metal, which requires a small resistance to the flow of molten metal. The first mock exam of the main runner is beneficial to the smooth runout of the main runner. It is very commonly used in production practice. One mold and one layout are adopted. The gating system has a transverse runner, the cross section of the runner is 22.5 x 1 x 1.3=29.25 cm2, the cross-section shape of the runner is measured, and the specific size is shown in the diagram.
To sum up, the 3D diagram of closed gating system is shown in the figure.
As shown in the figure, the total number of ingates is 1, the number of main runner is 1, and the number of sprues is 1.