| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an immersion tube of a vacuum degassing apparatus capable of suppressing a nitrogen component included in molten metal such as molten steel and contributing to the higher quality of the molten metal such as molten steel by suppressing air disposed at the outside of a castable layer from transmitting through the castable layer in the radially inner direction thereof to be transferred into a molten metal passage side. <P>SOLUTION: An immersion tube 1 includes: a core 2 set around a central axis 1p along the longitudinal direction; a brick layer 31 forming a vertical molten metal passage 30 passing the central axis 1p and arranged in a cylindrical shape at an inner peripheral side of the core 2; and a cylindrical-shaped castable layer 32 arranged at an outer peripheral side of the core 2 and formed by solidifying a fluid castable material. A gas permeation restricting member 8 having poor permeability against gas is provided in a cylindrical shape on an outer peripheral wall surface 32p of the castable layer 32. <P>COPYRIGHT: (C)2013,JPO&INPIT |
