Complex-moulding evaporative pattern casting method with foam pattern and clay or sodium silicate sand

Abstract

The invention provides a complex-moulding evaporative pattern casting method with a foam pattern and clay or sodium silicate sand, wherein the method mainly includes the following steps: 1) making an EPS pattern continuous gating system through common methods; 2) coating the EPS pattern by a ceramized coating; 3) placing the EPS pattern in a sand box and filling the EPS pattern with the clay or sodium silicate sand to perform moulding; 4) drying and evaporating the EPS pattern in a drying oven; 5) removing the EPS pattern and performing pouring; and 6) performing cooling to obtain a casting. The surface quality of the casting is approximate to the precision of a wax die, so that the method ensures casting quality, is environment-friendly in the casting process and is free of emission of harmful gas.

Description

technical field [0001] The invention relates to the field of casting, in particular to a composite molding gasification casting method of a foam pattern and clay or water glass sand. Background technique [0002] The casting technology with foam as the shape has a history of 60 years in the world, and the solid casting process is still used in foreign countries. There are two key disadvantages of the solid casting: one is the serious carbon defect of the casting, and the other is that EPS lacks vacuum negative pressure. The products of pyrolysis under oxygen conditions are small molecular harmful gases such as benzene, toluene, ethylbenzene, and styrene, which cause public nuisance. There is no effective and feasible treatment and purification method at home and abroad. [0003] Since 2008, the popularization of the technology of first burning out the foam and then pouring the molten metal in my country has overwhelmed the traditional full-shape casting process with absolute...

AI Technical Summary

Problems solved by technology

[0002] The casting technology with foam as the shape has a history of 60 years in the world, and the solid casting process is still used in foreign countries. There are two key disadvantages of the solid casting: one is the serious carbon defect of the casting, and the other is that EPS lacks vacuum negative pressure. The products of pyrolysis under oxygen conditions are small molecular harmful gases such as benzene, toluene, ethylbenzene, and styrene, which cause public nuisance. There is no effective and feasible treatment and purification method at home and abroad.

[0003] Since 2008, the popularization of the technology of first burning out the foam and then pouring the molten metal in my country has overwhelmed the traditional full-shape casting process with absolute advantages (the technology of burning out the foam first and then pouring is the invention patent of the inventor - ZL200810080960.8) , the technology of burning EPS first and then pouring is far more advanced than that of solid casting. EPS oxygen-rich combustion has no cracking reaction, and the main product is H 2 0+CO 2 , the carbon defects of castings are effectively reduced, but it is difficult to burn 100% of EPS for castings with complex structures, and generally there are still 10-15% dead corners left, so it is difficult to achieve a casting completely free of carbon defects and completely free of small molecule harmful gas emissions Require

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