In-depth exploration of the causes of cracks on the surface of continuous casting slabs1. Too high temperature of molten steel or too fast pulling speed is the
In-depth exploration of the causes of cracks on the surface of continuous casting slabs
1. Too high temperature of molten steel or too fast pulling speed is the main cause of longitudinal cracks. Because it is more difficult to cool the mold uniformly, the stress is always larger or smaller. The temperature of molten steel is high, the shell of the billet is thin and the strength is low. Small stress will tear the shell of the billet, causing longitudinal cracks. The high pulling speed is the same as the high temperature.
2, the tundish nozzle and the crystal fitting nozzle are not aligned or the casting nozzle is deformed, and the steel flow is offset. The billet shell growth slows down on the side close to the steel flow, the billet shell is thinned, causing cracks, and even the steel flow directly washes the billet shell and causes the phenomenon of steel breakout.
3. Insufficient amount of cooling water for crystal parts, low flow rate of water gap, local boiling of cooling water or uneven distribution of water jacket water flow will cause uneven cooling and cause cracks.
4. The crystal parts have been used for too long, and the copper pipes are seriously damaged, worn and deformed. In particular, the inverted taper becomes smaller, the air gap between the shell and the wall increases, heat transfer is blocked, and cracks are prone to occur.
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Harm of too high temperature: when molten steel out of cooper mold, the billet shell is thin and easy to break out; The accelerated erosion of refractory can ea
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1. The barrier function (mainly completed by the liquid slag layer) isolates the contact between air and molten steel, blocks the secondary oxidation of molten
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In continuous casting, low corrosion resistance often occurs, which directly leads to uneven composition and will eventually affect the smelting quality. In or