Low-pressure casting filling-mold air exhaust structure for sand mold and setting method for low-pressure casting filling-mold air exhaust structure

Abstract

The invention relates to a method for setting a low-pressure casting filling-mold air exhaust channel for a sand mold. The method comprises the following steps of: vertically drilling at least one deep hole for communicating the highest point of a cavity and the outside in the sand mold; downwards smearing a section of pasty fire resistant material layer in an orifice at the upper end of the deephole; drilling a small-aperture shallow hole communicated with the deep hole in the fire resistant material layer; and heating and hardening the fire resistant material layer, wherein when aluminum liquid rises steadily, the air in the cavity is exhausted from the small-aperture shallow hole; and when the aluminum liquid continuously rises through the deep hole in the sand mold and overflows fromthe small-aperture shallow hole, the aluminum liquid overflowing the plane of the sand mold is solidified quickly due to the relatively small aperture of the small-aperture shallow hole. Therefore, the air can be exhausted steadily during mold filling; after mold filling, the cavity is closed quickly, so that pressurization, pressure retention and crystallization are realized conveniently, and a reliable guarantee is supplied for improving the quality of a product. Furthermore, the height of a cover box sand mold is effectively reduced to 100 to 120 millimeters, the sand using amount of a cover box is reduced greatly, and the cost is saved.

Description

technical field [0001] The invention relates to a sand mold low-pressure casting mold filling and exhaust structure, and also provides a method for setting the sand mold low pressure casting mold filling and exhaust structure. Background technique [0002] Sand mold low-pressure casting is a process that uses compressed air to steadily press the refined aluminum liquid in the crucible into the sand mold through the riser. It has the following advantages: the liquid metal filling is relatively stable; the casting has good formability, which is conducive to the formation of castings with clear contours and smooth surfaces, and is more beneficial to the forming of large thin-walled castings; the casting structure is compact and has high mechanical properties; Liquid process yield. In addition, the working conditions are good; the equipment is simple, and it is easy to realize mechanization and automation. [0003] When filling aluminum castings in sand mold low-pressure casti...

AI Technical Summary

Problems solved by technology

Therefore, this process only uses low-pressure filling, which belongs to the low-pressure filling process, and cannot use crystal boosting.

The technology of low-pressure casting, especially sand mold low-pressure casting, has been greatly restricted.

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