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Water glass precision casting is widely used, covering almost all sectors of the national economy, and is used to manufacture silicone such as silica gel, carbon black, zeolite molecular sieve, sodium metasilicate pentahydrate, silica sol, layered silicon and instant powder sodium silicate, potassium sodium silicate, etc. Salt products are the basic raw materials of silicon compounds. In economically developed countries, the series of sodium silicate deep-processing products has developed to more than 50 types, some of which are used in high-tech and fine technical fields; they are indispensable for light industrial washing powder, soap and other detergents. of raw materials. It is also a water softener and sedimentation aid. It is used in the textile industry to aid dyeing, bleaching and sizing. It is widely used in casting, grinding wheel manufacturing and metal preservatives in the machinery industry. It is used in the construction industry to make quick-drying cement. , acid-resistant cement waterproof oil, soil solidifier, refractory materials, etc., and can be used to make silica fertilizer in agriculture.

1. Precision casting is a complex casting of various alloys, especially high-temperature alloy castings. For example, the streamlined outer contour and cooling inner cavity of jet engine blades are almost impossible to form using machining processes. Precision casting process production can not only achieve mass production and ensure the consistency of castings, but also avoid stress concentration on residual tool marks after processing.
2. Precision casting can reduce machining work because investment castings have high dimensional accuracy and surface finish. Only a small amount of machining allowance can be left in the parts with higher requirements. Even some castings only need to be polished and polished. Polishing allowance, can be used without machining. It can be seen that the use of precision casting methods can save a lot of machine tool equipment and processing man-hours, and save metal raw materials significantly.
According to statistics, among all casting production, 60 to 70% of castings are produced with sand molds, and about 70% are produced with clay sand molds. The main reasons are the low cost of sand casting, simple production process and short production cycle. Therefore, castings such as automobile engine cylinder blocks, cylinder heads, crankshafts, etc. are all produced using the clay green sand process. When the wet type cannot meet the requirements, consider using clay sand surface dry sand type, dry sand type or other sand type. The weight of castings produced by clay green sand casting can range from a few kilograms to tens of kilograms, while the castings produced by clay dry mold can weigh tens of tons. Generally speaking, for medium and large castings, resin self-hardening sand molds can be used for iron castings, and water glass sand molds can be used for steel castings. Castings with accurate dimensions and smooth surfaces can be obtained, but the cost is higher. Of course, the casting accuracy, surface finish, material density, metallographic structure, and mechanical properties of sand castings are often poor. Therefore, when casting performance requirements are higher, investment (lost wax) casting, die casting, low-pressure casting, etc. should be used. Casting method.