METHOD FOR CONTROLLING SURFACE TEMPERATURE OF INGOT IN CONTINUOUS CASTING MACHINE

摘要

PURPOSE:To decrease the defect of an ingot by correcting the temp. decreasing pattern of the ingot for each of watery spraying segments according to the change in casting speed. CONSTITUTION:The molten steel poured from a tundish into a mold is formed as the ingot after primary cooling in a mold and enters a secondary cooling zone. The casting speed signal from a casting speed measuring device 11 is inputted together with the surface temp. signal of the ingot from a surface thermometer 6 to a control device 10. The temp. decreasing pattern of the secondary cooling zone with respect to a standard casting speed and the equation (I) are preliminary inputted to the device 10 and therefore the temp. decreasing pattern is corrected according to the casting speed for each of the cooling water spraying segments. The temp. decreasing pattern of the secondary cooling zone is thus adequately maintained by the above-mentioned method, by which the ingot surface temp. at the straightening point is stably controlled. More specifically, the internal defects and surface defects are decreased.