| 摘要 |
PURPOSE: A submerged entry nozzle for continuous casting is provided which does not generate mold level hunting during casting to appropriately cope with continuous casting process, prevent casting stop, and stabilize the surface of molten steel in a mold. CONSTITUTION: In a submerged entry nozzle for continuous casting comprising a pipe part to the upper part of which an insert is coupled, a speed change part that is connected to the lower part of the pipe part, and inner passageways that are respectively formed in the pipe part and the speed change part to communicate melt flown in through an insert, the submerged entry nozzle for continuous casting is characterized in that length (L1) of the pipe part from the lower part of the insert to the speed change part is the same as or longer than length in which flowing separation of molten steel generated during casting is completed, the maximum inner diameter of the pipe part is equal to the minimum inner diameter thereof, an upper inner diameter (D1) of the pipe part that is positioned at the lower part of the insert is larger than a lower inner diameter (D2) of the pipe part that is positioned at the upper part of the speed change part, and inner diameter of the pipe part is constantly reduced as it goes from the upper part to the lower part of the pipe part, the insert comprises a part having the same inner diameter as the upper inner diameter of the pipe part, and length of the pipe part includes up to an insert part having the same inner diameter as the upper inner diameter of the pipe part, length of the pipe part is 6 to 8 times of an average diameter of the pipe part when a ratio of inner diameter of the insert (D0)/upper inner diameter of the pipe part (D1) is 0.4 or more but less than 1.0, and length of the pipe part is 6 to 8 times of an average diameter of the pipe part.
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