1.Influence of liquid iron level on mixing state in transition zone
It can be seen from the experimental results that under the condition of molten iron with the same viscosity, the mixing degree between molten steel and molten iron after entering the bucket teeth varies with the height of molten iron liquid level (when the liquid level is high (Experiments 1, 3 and 5), the mixing of the two liquids is light (the transition zone is narrow), while when the liquid level is low (Experiments 2, 4 and 6), the mixing of the two liquids is heavy (the transition zone is wide).
When the liquid iron level is low, in addition to the horizontal flow rate and downward diffusion speed when the liquid steel flows in, there is also a space from the liquid iron level to the gate. When the liquid steel falls to the liquid iron level, it has the effect of gravity acceleration, and enters the liquid iron like a “fierce son”, so that the flow rate of the liquid steel deviates from the horizontal angle and flows counterclockwise.
2.Effect of pouring time interval on the mixing state of two kinds of liquid steel
It can also be seen from the experimental results that when the liquid iron level is the same, the mixing degree of two liquids with high liquid iron viscosity is lighter than that with low viscosity (narrow transition zone). This is because the greater the viscosity of molten iron, the smaller the diffusion speed of molten steel in molten iron, and the lighter the mixing degree of the two liquids. The production test shows that when pouring bucket teeth, the liquid level of molten iron poured into the tooth tip should be increased as much as possible, so as to shorten the width of the transition zone and help to remove the scum on the surface of molten iron; The interval time of double liquid pouring should not be too long. Although extending the time can shorten the width of the transition zone, due to the limitation of the solidification temperature of molten iron, the time is too long, the bonding quality of double metals in the transition zone is not good, and the scum on the surface of molten iron is not easy to be washed by molten steel. Therefore, in production, attention should be paid to controlling the interval within a certain appropriate range.