Sand core design of axle housing

The sand core is designed to form the inner cavity, forming hole or the part with complex shape which is not easy to mold. The sand core shape of the axle housing is relatively complex, and the wall thickness change difference is up to 14mm. The sand core strength, fluidity and collapsibility are required to be good, and it belongs to class III sand core according to the complexity.

According to the basic principle of sand core setting, the number of sand cores should be reduced as much as possible, and the parts with regular shape and easy to fill sand should be set in one sand core. In the sand core design, we need to design the sand core along the axle housing structure.

The basic requirements of sand core are that the shape, size and position of sand core in the sand mold should be consistent with the requirements of the axle housing, with sufficient stiffness and strength. During the solidification process of the casting shell, the gas generated by the sand core can be eliminated from the mold in time. When the axle housing shrinks, the sand core does not give great resistance, so it is easy to clean the sand.

According to the three-dimensional drawing and the structure of the axle housing, there is only one cavity that runs through each other. The inner cavity structure is shown in Fig. 1. For this axle housing, resin coated sand can be used for core making and modeling, and a core with horizontal core head and vertical core head should be designed.

In the design of sand core head, the sand core is usually fixed in the mold by the core head, and other parts are also used to fix the sand core, such as core support and bolt. In this design, the core head is fixed, and the cold box core is used. The sand core consists of horizontal core head and vertical core head.

The sand core positioning is relatively critical, and it is not allowed to move along the core head or rotate around the core head; in this design, the sand core head is a circular structure with two vertical staggered core heads, which can accurately locate the position of the sand core in the mold, so it is not necessary to consider the horizontal movement and rotation of the sand core.

The inner cavity size of the core head is taken as follows: the length of the left core head is 50 mm, the length of the right core head is 50 mm, and the slope of the left and right core head is 3 degrees; the length of the upper core head is 50 mm in the vertical direction, and the length of the lower core head is 30 mm; the slope of the lower core head is 1 ° and the slope of the upper core head is 4 °. The length of horizontal core is 35mm. The core head structure is shown in Fig. 2.