Dynamic Method & System for Adjusting and Controlling Nodularization and Inoculation of Ductile Iron

doi:10.3901/JME.2017.20.054

Abstract

Abstract: The metallurgy status of the base iron has important influence on the nodularization effectiveness, inoculation effectiveness as well as the forming tendency of casting defects. The dynamic optimization control and adjustment of the nodularization and inoculation process have been studied based on the comprehensive evaluation for the actual metallurgy status of the base iron. Some key characteristic parameters are selected to represent multiple metallurgy properties of the base iron effectively. A comprehensive evaluation model is established tentatively to determine the qualified metallurgy status of the base iron and calculate the optimal addition amount of nodularizer accurately. In the significant steps of the nodularization, inoculation and final pouring process, there are corresponding test and evaluation methods, as well as control and regulation methods for the nodularization and inoculation effectiveness, so as to realize the closed loop control of the production process for ductile iron. The dynamic adjustment and control system mainly includes:The base iron metallurgy status regulation and control subsystem;The nodularization process and effectiveness regulation and control subsystem;The inoculation process and effectiveness regulation and control subsystem;The final nodularization and inoculation fine-tuning subsystem. Under the experimental condition of laboratory, the simulation production results show that the dynamic control method based on the base iron metallurgy status evaluation and the system could achieve the optimal control of the nodularization and inoculation for ductile iron.

Key words: base iron, ductile iron, dynamic adjustment and control, grey correlation, nodularization and inoculation

CLC Number:

TG143

LI Dayong, XU Zhenyu, MA Xuliang, WANG Lihua. Dynamic Method & System for Adjusting and Controlling Nodularization and Inoculation of Ductile Iron[J]. Journal of Mechanical Engineering, 2017, 53(20): 54-60.

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