Casting method of a main reducer housing

Abstract

The invention relates to a casting method of a main reducer housing. The casting method includes: a precoated sand core forming process, a smelting ball iron process and a casting process, the precoated sand core forming process includes core-making of precoated sand, coated sand type assembly and sand-type steel shot filling; the smelting ball iron process includes electric-furnace smelting and charging of molten iron and treatment; the casting method is characterized by including casting, unboxing, de-gating, one-step shot blasting, grinding, secondary shot blasting and detecting. With the method, exhaust smoothness is guaranteed, generation of hole defects in the casting is avoided from the sand core exhaust process, sand hole and pore defective reject rate is controlled within 1%, shrinkage or porosity defect is avoided, the casting is stable in size and high in surface smoothness, the yield is higher as compared with that with a traditional casting method of the main reducer housing, the production process is easier to control, and production competitiveness has higher advantages.

Description

technical field [0001] The invention belongs to the technical field of casting, and relates to a casting of main parts of an automobile rear axle, in particular to a casting method of a final reducer housing. Background technique [0002] The reducer housing is assembled on the rear axle of the car. Its structure is complex and has high requirements on mechanical properties. It is an important auto part and is usually cast by ductile iron. The traditional main reducer shell casting method is to incorporate a coated sand core into the green sand mold, the green sand forms the casting shell, and the coated sand core forms the casting cavity. However, this casting method has several obvious disadvantages: 1. It has high requirements on the quality of green mold sand mixing, and it is easy to produce casting defects such as sand holes and pores; 2. The dimensional accuracy is low; 3. The main reducer shell has many The sudden change of wall thickness is large, and the stiffness...

AI Technical Summary

Problems solved by technology

However, this casting method has several obvious disadvantages: 1. It has high requirements on the quality of green mold sand mixing, and it is easy to produce casting defects such as sand holes and pores; 2. The dimensional accuracy is low; 3. The main reducer shell has many The sudden change of wall thickness is large, and the stiffness of green mold sand mold is low, which is not conducive to eliminating shrinkage cavity and shrinkage defects; 4. The surface of the casting shell is rough

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