The stomatal castings are widely found in the castings. How to solve the porosity defects of castings has been a problem of many manufacturers' headaches because the stomatal causes a lot of pressure castings to be discarded, resulting in waste of production costs. Infiltration is widely used in the automotive industry, gas and hydraulic industry, pressure components manufacturing, powder metallurgy industry and so on. The use of excellent impregnation process after the product can not only save the quality of bad cost, fully able to meet the temperature, vibration resistance, sealing and other requirements, but also to further improve the casting of the compactness, timeliness and other characteristics. Infiltration is to solve the problem of casting porosity and is the best cost-saving program, with the world's environmental protection, quality requirements, infiltration is not simply a temporary plug of substandard products, and more Is a kind of quality protection, in the developed countries of the automotive industry has been impregnated as a necessary process; in the country, infiltration is also more and more attention.