2004 Volume 44 Issue 2 Pages 350-355
The swirling flow formation in the submerged entry nozzle has been proposed by Yokoya et al. as a fundamental and effective technology for controlling the flow pattern in the mold.1-4) We started a joint study in 1997 with Nippon Institute of Technology, Osaka University and Kyushu Refractories to develop a swirling flow submerged entry nozzle as a root measure to improve flow pattern in molds.
As a first step of the development, the basic effect of the swirling flow in the single port submerged entry nozzle for the round billet casting was confirmed by a wood metal experiment, which forms upward flow along the mold wall caused by centrifugal force. As a result, we achieved conclusions as follows;
(1) The basic effect of the single port swirling flow submerged entry nozzle appears in the case that Swirl number in the nozzle SW=0.3 or more, which forms upward flow along the mold wall.
(2) In the case that the swirling flow in the submerged entry nozzle and the M-EMS (Electromagnetic stirring in mold) were combined in the opposite direction of rotations by appropriate balance of intensity, the upward flow along the mold wall in the same level as the case without M-EMS was formed. It means that the outlet flow from the swirling flow submerged entry nozzle limited at the upper portion of the mold and the rotation flow formed by the M-EMS at the lower portion of the mold were separated clearly with less interaction.