The planet carrier ductile iron casting is one of the main components of the planetary gear transmission. The planetary axle or the bearing is mounted on the planet carrier. When the planetary gear is used as the basic component, it is the component that receives the greatest external torque in the mechanism. The planet carrier is mainly formed by casting, and the quality of the planet carrier castings is required during the casting process.
Planetary frame castings are high-strength ductile iron, which has high smelting process and operation difficulty; high dimensional accuracy and surface quality requirements; the connecting ribs on the castings are thicker, and casting defects such as shrinkage and shrinkage holes are easily formed in the parts. Internal quality is difficult to guarantee. In order to avoid the shrinkage and shrinkage phenomenon occurring during the casting process, it is particularly important to develop a planetary frame casting mold which can improve the process yield of the casting and avoid the defects of the casting quality.
The casting mold of the planetary frame casting, including the sand box, the casing and the mud core, the hollow core is made by using the hot core box outer mold, the casing includes an upper casing and a lower casing, and the casing is in the central shaft hole with the top of the planet carrier A corresponding Φ90×120mm heat-insulating riser is provided for feeding, and a casting process is carried out by pouring from the riser to disperse the molten iron, so that the casting solidifies according to the principle of solidification in order, eliminating Internal shrinkage and shrinkage defects.
The sand box is a special sand box, which controls the sand consumption of the casting and the sand box to be 20-30mm. The sand box plays the role of rapid solidification of cold iron to improve the feeding effect of the casting and reduce the shrinkage and shrinkage defects of the casting. Solving the problem of filling and feeding, and simplifying the production operation, the casting process of the planetary castings produced by the mold has a production rate of more than 85%.