Производитель погружного раствора

It is important to know that the shape of the sand has an important impact on the surface finish of the casting. Circular sand is better than triangular sand because the triangular sand has a large gap, which is easy to lead to defects such as porosity; According to the nature of the casting, the sodium silicate quartz sand is selected to form a spalling layer, and combined with the characteristics of cooling and shrinkage of the casting, the surface defects are reduced. Coating a protective layer on the surface of large castings, such as the film on a coated sand mold, can improve the surface finish of the sand mold and reduce the surface defects of the casting.  

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The roller drill uses the rolling action of the roller bit to break the rock and is suitable for drilling holes of 150 ~ 440 mm in diameter on the hard rock. It has the advantages of high efficiency and low labor intensity, and is widely used in large and medium-sized open-pit metal mines. The drill consists of an impactor (or drill bit), a rotary mechanism, a lifting mechanism, a pressure device, a walking mechanism, a slag discharge system, a drill frame and a drill pipe. Rotary drilling machines are only suitable for drilling softer minerals and coal.

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