Research On The Secondary Cooling Technology Of Continuous Casting Billet And Its Application At Jinan Iron & Steel Company Co.

There are two billet continuous casters in the first steelmaking plant of Jinan Iron and Steel Co. Ltd. After long operation, it is found in recent years that the secondary cooling spraying water system(spraying water model) can't meet the requirement, which the high efficient continuous casting ask for on quality, production rate and casting speed. So, the subject"Research on the Secondary Cooling Technology of Continuous Casting Billet for No.1 Steelmaking Plant at Jinan Iron & Steel Company Co. and its Application"is established and the research has been done.The major research work has been done as follow:Test mechanical behavior and physical property of steel casting blank under high temperature because billet of medium and high carbon steel is more liable to crack etc. quality defect than plain steel. The test result provides basic data for simulating secondary cooling, making appropriate secondary cooling system, producing steel 45.Nozzles'cool characters are tested used by the two casting machine. The result shows that these five kinds of nozzles'performance is stability and reliable. The important data from the test provide relatively accurate boundary condition for the mathematic model and ground for optimization nozzles'layout. Analysis to the spraying structure of secondary cooling zone in two caster machine shows: the area of spraying water is long; the effective spraying coefficient is low, the relationship between spraying angle of nozzles and distance of nozzles'front-end to surface of blank can be adjust; the layout of stay bearing staff and the arrange of nozzles in the intermediate zone should be noticed avoiding the non-uniform cooling in the casting direction.Heat transfer of mathematic model of billet is built corresponding with casting machine structure of No.1 steelmaking plant. The model adopt effective spraying water coefficient and effective specific water flowrate to simulating secondary cooling, and get the numeric value of effective water flowrate about three cross-sections against two caster.The new secondary cooling model of spraying water is established. The new model take account into the casting temperature(steel temperature in tundish), molten steel component and cooling water temperature in different season on the spraying water of each block in secondary cooling zone. The new model is shown: Q = K( a+bv+cv~2 )+d(â–³T-20)+F...