Casting process parameters mainly include dimensional tolerance, linear shrinkage, draft angle and other aspects. The determination of these process parameters depends on the structural complexity of the axle housing, the design of the axle housing and the existing technological level, the precision and quality of the molding tooling, and the types of casting metals and alloys, which have an important impact on the shape and size control of the axle housing.
Casting dimensional tolerance refers to two allowable limit dimensional tolerances of casting nominal size.
The higher the requirements for the dimensional accuracy of the axle housing, the higher the requirements for the design level of, the performance and quality of molding and core making materials, the equipment and tooling for molding and core making, heat treatment process, cleaning quality, and the management level of casting workshop, etc., and the production cost of the axle housing should also increase. Therefore, when determining the dimensional tolerance of the axle housing, it is necessary to ensure that the axle housing can meet the requirements of processing, assembly and use, and reduce the production cost.
According to the standard of gb6414-1999, the casting dimension tolerance grade is set as 16, and the codes are divided into CT1 to ct16. According to the literature, the production process is sodium silicate, the dimensional tolerance of sand casting is ct12-ct14, and the machining grade of mechanical allowance is MAH.