Research status of vibration of centrifugal casting machine on filling process of molten metal

McBride’s research focus is to establish the prediction method of entrainment and exhaust in centrifugal casting process. They used the method of combining theory with experiment. First, they established a theoretical prediction model, then carried out the experiment, and then used the results of the experiment to modify the theoretical model. In the experiment, water was used as filling liquid, and a series of filling process images were collected by using high-speed image capture technology. In their experiments, they found some phenomena that were ignored in the theoretical modeling, such as the bubble involved when the first molten metal collided with the mold during casting, and so on. In view of this, they used higher-order calculation method to capture the formation process of vortex, and improved the original theoretical model.

Song Nannan et al. Established a mathematical model to describe the filling of rotating cavity by fluid in horizontal centrifugal force field, and programmed with C + + language to simulate the filling and solidification process of horizontal centrifugal casting. The results show that the liquid metal is evenly distributed on the inner wall of the mold in the form of helix after casting, and the “pitch” formed by the first liquid flow decreases with the increase of the rotating speed. The higher the rotating speed is, the easier the liquid metal is to evenly spread over the mold cavity. In addition, the pressure field presents an irregular concentric circle at low rotating speed, while at high rotating speed, at the same radius, the liquid metal is compressed The forces are almost equal.

Wu Shiping and Li Changyun established a mathematical model of filling process in vertical centrifugal casting, and simulated the filling process with their own casting simulation software. The effects of two different casting positions on the filling effect were investigated. The results show that the flow of molten metal is stable during bottom casting, and the casting quality is better than that of top casting. They also used SOLA-VOF algorithm in the numerical simulation. The disadvantage of their mathematical model is that in order to compare with the hydraulic test results in the follow-up study, they only solved the Navier Stokes equation in the numerical simulation, but did not take the heat conduction equation into account.

Li et al. Studied the influence of different casting systems and different mold rotation speed on the filling ability of liquid metal by hydraulic test. The test device used high-speed camera to capture the images in the casting process. Four casting methods were investigated, including top casting, bottom casting, side casting and step casting. The results show that: the filling effect of bottom casting and step casting is better than the other two casting methods; within a certain speed range, the filling ability of liquid metal increases with the increase of mold speed; when the speed reaches a certain height, increasing the speed will have a negative impact on the filling ability.