| 摘要 |
PURPOSE:To cast a hollow ingot for pipe making continuously without undergoing a hot boring stage by providing a casting space in the bottom part of a water cooled mold, supplying molten steel at all times therein to form a cylindrical shell-like trailing solidified shell, and taking up the same upward by allowing the same to trace the leading solidified shell and to join therewith. CONSTITUTION:Molten steel is introduced into the spacing S formed between the slope on the inside wall in the downward converging bottom part 3a of a water cooled mold, and a leading solidified shell 1. The steel 2 introduced therein forms a trailing solidified shell 6 like a cylindrical shell by inducing swirling flow while the steel is held in said space S, thereby allowing the same to trace the shell 1 and to join therewith. The joined shell is taken up upward and the steel 2 is again introduced into the spacing S produced by the drawing. By repetition of such operations, the hollow ingot for pipe making, particularly, a blank material for seamless steel pipes such as oil well pipes, is cast continuously. |
