Study Of Induction Casting System Based On Small Hole Outflow Model

The overall copper smelting industry in China is growing steadily,but the copper ingot casting is often operated by manual or semi-automatically,with a low degree of automation and a poor working environment,high labour intensity and high scrap rate.This paper designs a set of induction casting system according to the casting quality requirements of the factory,and studies the control method of quantitative casting,so that it can not only collaborate with the automatic production line of copper ingots planned by the enterprise,but also produce copper ingots that meet the quality requirements with high precision quantitative casting,so as to realise the automatic production of copper ingots eventually.Firstly,the characteristics of common casting methods and quantitative control methods are analysed.According to the production environment and casting process requirements of the ingot casting production site,the paper adopts the stopper-rod casting machine and proposes a quantitative method based on the small hole outflow model.Secondly,the overall structure of the induction casting system is designed in accordance with the basic principle of induction heating and the working principle of the stopper-rod casting machine.The casting furnace and induction coils are designed and the operating frequency of the mid-frequency power supply is determined based on the thermal physical parameters of the copper metal and the rated power required to maintain the liquid state of the copper metal in the induction casting system;based on the working principle of the induction casting system,the stopper-rod executing part and the weighing module are designed and the device of them are selected.Then,the quantitative casting method based on the small-hole outflow model was studied.The mathematical relationship between the outflow time and the liquid level as well as the relationship between the weight of the molten copper metal in the casting furnace and the liquid level are derived based on the small-hole outflow model,the mathematical model of the casting time is established and the influence of the outflow coefficient on the outflow is analysed.The mathematical model of the weight of the molten copper metal and the liquid level height is verified using the mass properties module of the 3D design software.Finally,according to the process requirements of copper ingot casting and the operation principle of the system,hardware circuits such as pneumatic control module,weighing module and self-test protection module are designed,and the HMI interface,casting time calculation program and quantitative casting control program are developed to realise the function of automatic copper ingot casting.By building a simulation platform for quantitative casting,a flow coefficient measurement experiment and a quantitative casting simulation experiment are designed to verify the feasibility of the quantitative casting method based on the small-hole outflow model.The induction casting system is further set up and test at the ingot production site.A quantitative casting experiment is designed to test and compare the time quantitative method,the weighing quantitative method and the quantitative casting method based on the small hole outflow model.The experimental results show that the induction casting system based on the small hole outflow model is highly stable,feasible and has a high degree of automation.