Precautions for Process Operation of Pig Iron Castings in Jiangsu Foundry
When molding pig iron castings, a layer of plastic film is first covered on the template, and vacuum pump is used to extract air to make the film tightly adhere to the template. Then, a sand box is placed, and molding materials are filled into the sand box. After being compacted and scraped flat, plastic film is used to cover the top surface of the sand box. The vacuum pump is connected to suck out the air between the sand particles, causing negative pressure to form inside the sand mold. The vacuum of the template is removed together, allowing the plastic film to adsorb onto the inner surface of the mold, The sand mold has a certain strength and hardness due to the effect of pressure difference. After demolding, box closing, pouring, and condensation cooling, the required casting can be obtained by removing the negative pressure.
The casting process of pig iron castings refers to the selection of suitable parting surfaces, shapes, and core making methods based on the structure, weight, and scale of pig iron castings, as well as the characteristics of casting alloys and production conditions. The reasonable setting of casting ribs, cold iron, risers, and pouring systems ensures the achievement of excellent castings. Process operation: It is necessary to formulate reasonable process operation procedures for pig iron castings, improve the overall technical level, and ensure the correct implementation of the process procedures.
When planning, in addition to confirming the shape and size of castings based on working conditions and metal data performance, it is also necessary to consider the rationality of planning from the perspective of casting alloys and casting process characteristics, namely significant scale effects and issues such as condensation, shortening, and stress, in order to prevent or reduce the occurrence of defects such as component segregation, deformation, and cracking in castings.