Research status of large nodular iron castings

According to the data reported by China Foundry Association at the industry annual meeting in recent years, the total amount of nodular cast iron castings has increased by about 5% in recent years. In 2016, the total amount of ductile iron castings reached 13.2 million tons, which was higher than that of all alloys except gray iron. The main achievements in the research and production of large ductile iron in China are concentrated in the field of wind power casting. Although there are many successful cases in other fields, the proportion of tonnage is not high.

In the domestic market, several large suppliers such as Dalian Heavy Industry Co., Ltd., Shandong Longma Co., Ltd., Shaanxi shanchai Co., Ltd. and Jiangsu Jixin Group Co., Ltd. have achieved important success in the field of foundry technology research in the field of ductile iron castings for marine and gas turbines. In the field of foundry technology research in the field of marine and gas turbine ductile iron castings, several larger suppliers such as Ningxia share, Shaanxi shaanchai and Sichuan Dongqi have made important achievements. These domestic suppliers have outstanding achievements in their respective fields of technology research and development, at the same time, they also show the relative backwardness in the research and development of ductile iron casting technology to varying degrees. It is still a difficult problem to break through for the research and production of high-precision ductile iron castings.

According to the current research results and market research results, the casting technology of nodular cast iron in China is still in a high requirement stage of heavy quality and low cost. Based on the innovation and invention of new materials and the improvement of process control in the production of nodular cast iron castings, it is necessary to study new inoculation methods, new process schemes, pure molten iron and other cutting-edge technologies to improve the quality stability. Through technical innovation, the graphite of casting is refined and the structure is uniform, which makes the casting production more perfect. In the field of casting application, the research and development of nodular cast iron should continue to expand the coverage, such as gas turbine intake cylinder, thermal power low-pressure cylinder, diesel engine block, automobile casting and other fields. Therefore, it is necessary to further strengthen the research of high precision end ductile iron casting technology in many fields in China.