Introduction to the structure of large planetary carrier steel castings

The gating system is the channel in the sand mold to guide the molten steel into the cavity. In the actual production, a series of casting defects are often caused by unreasonable design of gating system, which will lead to direct scrap of castings. Therefore, the design of gating system is closely related to the quality of castings.

The planet carrier is made of ZG35CrMo, and its basic outline size is 1260 mm × 1260 mm × 647 mm。 The structure is symmetrical as a whole, the wall thickness is relatively uniform, the thickest part is 91 mm, the thinnest part is 44 mM, the volume is 0.619 m3, and the part weight is 1330.491 kg. The part model is established by CATIA, and the part model is shown in the figure.

The casting pouring position should be selected according to the solidification mode of the casting, and the casting should be fully filled. During the design, the lower flange of the casting is placed at the bottom to ensure the smooth rise of liquid steel in the mold and avoid casting defects on the surface and inside of the upper flange. The bottom injection scheme is adopted with the casting placed upright and the flange facing down. Six ingates are set on the lower flange, and one runner and one sprue are set in addition.