“Energy conservation” and “environmental protection” are important issues facing China in development, and realizing sustainable development is our basic national policy. Therefore, in casting production, more emphasis is placed on simplifying processes, saving energy, reducing costs, and reducing or avoiding the impact of production on workers and the ecological environment around the factory. The selection of molding process and materials plays a key role in energy saving and environmental protection of foundry. From the perspective of energy saving, the molding process with simple process, low energy consumption and high efficiency is preferred. From the perspective of environmental protection, the following points should be paid attention to:
1) Casting production will produce a large number of waste sand. If these waste sand can not be treated and reused, it will bring disaster to the surrounding environment;
2) Dust from sand treatment process;
3) The decomposition of organic substances such as resin during molding, core making and pouring, the harmful waste gas released by solvent volatilization, and the dissolution of acid-base substances in water are all the sources of pollution.
To sum up, it is of great significance to adopt molding processes and materials with low energy consumption, less pollution and no pollution. Wet molding clay sand process just meets the above requirements. On the basis of comprehensive control of wet molding clay sand material, process and process, it will have a better prospect.
It comes from the cooperation project of “process optimization and defect prevention of steel castings of coupler and buffer” between Professor Fan Zitian of Huazhong University of science and technology and CSR Changjiang Vehicle Co., Ltd. Tongling branch of Changjiang Company is a professional production base of important steel castings for couplers, buffers and other vehicles. In order to meet the needs of establishing energy-saving and environmental protection enterprises, improve the yield and quality of castings and reduce the repair rate and cost of steel castings, the company has formulated an overall technical transformation plan, and implemented the technical transformation based on the mature production process of Wet Mold clay sand steel castings in the United States, Build a wet molding clay sand molding production line, and the sand core adopts triethylamine gas hardening resin sand (or CO2 gas hardening sodium silicate sand). Based on the cooperation terms, Huazhong University of science and technology is mainly responsible for determining the proportion of green molding clay sand suitable for steel castings such as couplers and various performance parameters to be met by molding sand in the early stage; The mid-term research work includes computer simulation and optimization of the production process of hook body and hook tongue, and determining the process scheme of product trial production; In the later stage, it mainly carries out macro qualitative research and micro analysis on the defects of steel castings in the process of trial production and mass production, puts forward control measures and solutions, and realizes the continuous optimization of process scheme, so as to ensure the production of high-quality parts.
Although the production of railway steel castings with green clay sand belongs to small and medium-sized steel castings, there are still control difficulties in this process in view of the characteristics of green clay sand and steel casting. It requires high-quality molding sand raw materials and accurate control of the whole process, so as to give full play to the advantages of high production efficiency, low cost, short production cycle, low energy consumption, continuous production and easy mechanization of green clay sand. Therefore, on the basis of previous relevant tests and research and based on the project platform, in-depth research will be carried out in the aspects of mold performance parameter requirements, molding sand formula, casting process simulation and optimization, casting defect prevention and control elimination of green clay sand steel castings, so as to form a set of stable process scheme, serve enterprises, enrich domestic research in this field, and finally provide strong technical support for actual production, Contribute to the development of railway and related fields.