PURPOSE: To simply manufacture a pipe without any internal defect by supplying a metallic core into molten metal covering surface with flux to cast a hollow cast billet and rolling for pipe-making after taking out this out this core.
CONSTITUTION: The molten metal 4 is received into a tundish 13 connecting with upper part of a mold 1 in continuous casting apparatus through a brake ring 12 from a pouring nozzle 16 through pouring pool 15. The surface of the molten metal 4 is covered with the molten flux layer 6. Successively, the metallic core 2 of steel pipe, etc., is supplied into the molten metal 4 through the above molten flux layer 6 and by continuously descending, the hollow cast billet 5 is integratedly drawn from the mold 1 and cast. Then, the molten flux stuck to the surface of the core 2 forms the solidified flux layer 8 between the core 2 and the hollow cast billet 5. After that, this flux layer 8 is made to molten or semi-molten state to take out the core 2. Successively, the hollow case billet 5 is rolled for the pipe-making under sticking condition of the flux at inner face. By this method, fault in inner part is made to less and the service life of boring tool is extended.
BESSHO NAGAYASU
SUZUKI HAJIME
FUJII TETSUYA
IMAE TOSHIO
HASE MINORU
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