IMMERSION TUBE

PROBLEM TO BE SOLVED: To provide an immersion tube which suppresses the thermal deformation of a core metal and is easily constructed. SOLUTION: The immersion tube 10 roughly includes the cylindrical core metal 11, an inner surface brick 13 coating the inner circumferential surface of the core metal 11 and a castable refractory 16 for covering the outer circumferential surface side of the core metal 11 and also forming the lower end part of the immersion tube 10, The immersion tube 10 further includes circulation gas piping 20 which serves as a feeding passages for circulation gas and is disposed on the outer circumferential surface of the core metal 11. The circulation gas piping 20 has circumferential-direction piping 21 disposed along the outer circumferential surface at lower end part of the core metal 11 and vertical piping 22 for feeding the circulation gas into the circumferential-direction piping 21. The circumferential-direction piping 21 has square-shaped cross section and includes discontinuous four pieces of partial piping 21a, 21b, 21c, 21d. In each piece of the partial piping 21a, 21b, 21c, 21d, vertical piping 22 is provided and the circulation gas is supplied into the respective partial piping 21a, 21b, 21c, 21d through four system of the vertical piping 22. COPYRIGHT: (C)2010,JPO&INPIT