How to better deal with the slag entrapment of the crystallizer1. The immersion depth of the nozzleIf the nozzle is immersed, the depth of the liquid is too dee

How to better deal with the slag entrapment of the crystallizer

1. The immersion depth of the nozzle

If the nozzle is immersed, the depth of the liquid is too deep, and it is easy to reflux and slag; if it is too deep, the chance of inclusions and bubbles being caught in the depth of the casting slab is increased, and the hot spot moves downward, which increases the probability of steel breakout and causes slagging. Poor, poor lubrication.

2. Water outlet area

The original immersion nozzle has a large upper mouth and a small lower mouth, resulting in a fast jet velocity at the outlet of the lower mouth, a strong impact on the liquid surface, and a large range of liquid level fluctuations; at the same time, the lower mouth is easy to adhere to cold steel, which is easy to form bias currents and vortexes. The possibility of slag entrapment is increased. The pulling speed is too slow, which is easy to cause backflow entrapment.

3. Drawing speed

The drawing speed is faster, the melting structure of the mold flux is changed, the thickness of the molten slag layer becomes thinner, and the probability of the powder slag layer being wrapped in the molten steel increases; the drawing speed is too slow, and it is easy to cause backflow and slag entrapment.

4. Mold powder viscosity

In the case of ensuring that the mold powder can smoothly flow into the gap between the mold and the cast surface of the cast slab, the viscosity of the mold powder should be appropriately increased to ensure the appropriate thickness of the liquid slag layer.