Lost wax castingThe craft is developed from the ancient casting craft. In the late Neolithic period more than 5,000 years ago, ancient Chinese craftsmen widely used the lost wax casting process in the manufacture of bronzes. According to the characteristics of plasticity and thermal volatility of beeswax, the craftsmen at that time first carved the beeswax into a wax mold of the required shape, then wrapped the clay outside the wax mold and reserved a small hole, dried it and roasted it to vaporize the wax mold. At the same time, the clay becomes a ceramic shell, and the female mold of the wax mold is left on the inner wall of the shell. At this time, the molten metal is injected into the shell along the small hole, and the shell is broken after cooling to obtain the required metal casting billet. The basic principles of modern lost wax casting technology are the same, but more complex and sophisticated. This is mainly reflected in the stricter requirements for the precise position of the wax model. The wax model obtained in modern technology is not only the direct engraving of the wax, but also the female mold can be obtained by molding the metal original mold (plate) with silica gel, and then the wax model can be obtained by injecting wax from the silicone female mold. The casting material is no longer clay, but instead cast plaster. Such products are much finer than ancient castings.

Guangdong alloy steel castingDewaxing casting process allowance: In order to ensure the sequential solidification of the castings, it is sometimes necessary to increase a certain part of the casting allowance. This extra part that exceeds the specified machining allowance is called the process allowance.

Dimensional tolerance of dewaxing casting castings: see GB/T6414-1999

Dewaxing casting fillet: The casting fillet radius R (mm) can generally be calculated according to the following formula: where, 'is the thickness of the adjacent wall of the casting. ) Can be calculated as follows:

Dewaxing casting slope: the size of the casting slope of the casting is related to the relative position between the surface of the casting and the metal mold. Any surface that tends to separate from the surface of the metal mold when the casting is cooled, should be given a smaller casting slope, stone row dewaxing casting, and any surface that tends to pack the metal mold or core when the casting is cooled, bridge head dewaxing casting, Should be given a larger slope. Example: For the holes and recesses of the casting, the casting slope should be larger, generally 2°-7°, and 2°-3° for the unmachined surface.Guangdong carbon steel castingThe machined surface can be 3°-7°