Process for improving surface quality of casting

Abstract

The present invention provides a process for improving the surface quality of the casting. The process is as below: roasting a shell mold by using a segmented heating roasting temperature mode, wherein when a sand box size is less than 500 mm, the distance between the outer side of the shell mold and the sand box is greater than or equal to 50mm, and the distance from the shell mold bottom to the sand box bottom is greater than or equal to 120mm; placing the prepared shell mold into the sand box prepared according to molding process, sealing a pouring gate and an insulation riser on the shell mold with tapes, then adding formulated mixed sand, conducting ram-jolt on the shell mold filled with sand by a molding jolter to form sand mold. The sand box is injected with mixed sand formulated with an alkaline phenolic resin, and has better strength and stability, can further improve the surface precision of casting and improve the quality of casting.

Description

technical field [0001] The invention relates to a process for improving the surface quality of castings, belonging to the technical field of machinery. Background technique [0002] The commonly used precision casting method is usually to obtain castings from mold making, wax mold making, shell mold making, roasting, and pouring metal. For some castings with complex structures, especially the shell molds with different thicknesses and sizes, the strength cannot be guaranteed, and the quality of the castings is also difficult to guarantee. Therefore, in the industry, this kind of castings are generally completed by sand casting, but Sand casting cannot achieve the dimensional accuracy of precision casting, and the surface quality and precision of castings are poor. Contents of the invention [0003] In order to overcome the defects of the prior art, the invention provides a process for improving the surface quality of castings. [0004] Technical scheme of the present inv...

AI Technical Summary

Problems solved by technology

For some castings with complex structures, especially the shell molds with different thicknesses and sizes, the strength cannot be guaranteed, and the quality of the castings is also difficult to guarantee. Therefore, in the industry, this kind of castings are generally completed by sand casting, but Sand casting cannot achieve the dimensional accuracy of precision casting, and the surface quality and precision of castings are poor