Casting method of automobile steering knuckle

Abstract

The invention relates to a casting method of an automobile steering knuckle. According to the casting method, a steering knuckle die cavity is arranged obliquely, and meanwhile a branch gate (1) is added so that molten iron can flow through a hot spot A part (2) for filling casting preferentially and smoothly; and thus, the defect of sand inclusion or slag inclusion caused by turbulence of moltenirons from many places to enter the steering knuckle die cavity simultaneously is eliminated effectively. According to the casting method, not only can the defects of shrinkage porosity and shrinkagecavity of the hot spot parts of the steering knuckle as well as the defects of appearance sand inclusion or slag inclusion be eliminated effectively, but also the product quality, the rate of finishedproducts, and the utilization rate of the molten iron can be improved effectively; and meanwhile the purpose of reducing the production cost is achieved, and the casting method is suitable for extensive promotion and application.

Description

technical field [0001] The invention relates to the technical field of casting of automobile parts, in particular to a method for casting an automobile steering knuckle. Background technique [0002] It is known that the steering knuckle is one of the main parts of the automobile steering assembly, which is used to connect the steering wheel of the automobile and the front wheel axle, and is connected with the shock absorber at the same time. The function of the steering knuckle is to bear the front load of the automobile, support and Drive the front wheel to rotate around the kingpin, so as to achieve the purpose of turning the car. Due to the complex shape of the steering knuckle, it is composed of three parts: the supporting journal, the flange and the yoke, and the structural characteristics of the four types of parts such as the shaft, the sleeve, the disc ring, and the yoke are concentrated. At the same time, the steering knuckle is still an automobile The quality of ...

AI Technical Summary

Problems solved by technology

Due to the complex structure of the steering knuckle, there are many joints between the thin-walled position and the rear wall position, which makes the steering knuckle very easy to cause more thick and large hot joints in the casting process due to its thick and thin connection structure. Shrinkage porosity, shrinkage cavity, and defects such as sand holes or slag holes are generated due to the liquid iron washing the mold wall from top to bottom. Therefore, most of the existing steering knuckles have defects such as unstable quality and low yield.

[0003] In order to overcome the above defects, it has been found through research that there is a great relationship between the defects of the existing steering knuckle and the casting method, mainly because the molten iron will flow through the hot joint during the filling process of the overflow riser. This results in a longer time for the temperature of the hot joint to diffuse to the mold wall, resulting in an increase in the heat energy coefficient of the hot joint, and the overflow riser will solidify first in the subsequent solidification process due to the low temperature of the molten iron that first flows in. The heat energy slowly disappears, and the hot joint reaches the freezing point. When the liquid shrinks and needs to be fed, the overflow riser has already solidified, so that it can no longer provide supplements to the hot joint, which in turn causes shrinkage and shrinkage in the casting below the overflow riser. Hole defects; through X-ray inspection of steering knuckles, it is known that about 60% of the casting gates have shrinkage porosity and shrinkage defects of different sizes. Among them, the defects exceed the acceptable requirements and are not About 30% are judged to be scrapped, and sand holes and slag holes caused by molten iron scouring the mold wall account for about 20%. These factors directly lead to the serious consequences of low yield and high production cost of steering knuckle castings. Wait

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