Falling Position Control of Outflow Liquid from Pouring Mouth of Ladle with Flow Guide in Tilting-ladle-type Automatic Pouring Machine

Abstract

  This paper discusses with an advanced control system for tilting-ladle type automatic pouring machines used in metal-casting industry. In order to precisely pour the liquid outflow from a ladle into a sprue cup of a mold, a falling position control system of the outflow liquid is proposed in this paper. In the proposed approach, a mathematical model on the falling position of the outflow liquid is derived from the shape of the ladle and the pouring conditions. The proposed mathematical model is verified by the experiments using a system which monitors the trajectory of the outflow liquid. In this study, the pouring process to the ladle which has a pouring mouth with a flow guide was analyzed mathematically. The falling position of the outflow liquid was varied with the tilting angle of the ladle according to the effects of the flow guide. The results confirmed that the flow velocity of the liquid from the ladle is increased by the contraction of cross-section of the liquid. This means that the flow velocity estimated by the mathematical model must be compensated using the experimental data. This paper therefore proposed a compensation method. Based on the model analysis, the falling position control is constructed by feedforward control using the proposed falling position mathematical model. The effectiveness of the proposed control system was validated through the experiments using an automatic pouring machine with a monitoring system.