Simulation Research of Flow Field in Continuous Casting Mold with Vertical Electromagnetic Brake

Abstract

The narrow face of continuous casting mold is the first impact region of the jet from the submerged entry nozzle (SEN), and against the characteristic a new pattern of electromagnetic brake device is proposed, which is called Vertical Electromagnetic Brake (V-EMBr) and its magnetic poles can cover the free surface and the frontier region of solidified shell. The effect laws of magnetic flux density, casting speed and the submergence depth of the SEN on flow field in mold with V-EMBr are investigated by numerical simulation method. The results show that with the magnetic flux density increasing, inhibitory effect of electromagnetic force on molten steel from SEN is increased gradually, impact strength of molten steel stream on narrow face is weakened gradually, the vortex center of lower recirculation zone is moved up gradually and the flow velocity of free surface is decreased gradually. These can reduce the fluctuations of free surface and chance of slag effectively, suppress impinging depth of molten steel in lower recirculation zone and float air bubbles and inclusions beneficially. In addition, the V-EMBr technology can also be applied to different casting speed and different submergence depth of the SEN in continuous casting process. The significantly metallurgical effects and flexibility of application range which are generated by V-EMBr is in line with the original intention of the V-EMBr design.

Modeling Study of EMBr Effects on the Detrimental Dynamic Distortion Phenomenon in a Funnel Thin Slab Mold

“…Two types of EMBr are considered: firstly, positioning longitudinally in the mold below the SEN tip, which has demonstrated excellent results in previously published works [34,35,38,40,41]. The second is a novel EMBr position located vertically close to the narrow mold walls, showing promising results during its application in conventional molds [32][33][34] and representing a new opportunity for turbulence control and meniscus stability with lower EMBr intensities.…”

“…This new application is close to the narrow mold faces. It is called vertical-EMBr [32,33], which has been applied even jointly with the longitudinal-EMBr [34], yielding excellent metallurgical results in conventional slab molds. Because of the successful results in conventional casters, this technology is applied in thin slab molds.…”

Electromagnetic Forces in Continuous Casting of Steel Slabs

“…Vertical single-ruler EMBr, recently proposed, is designed to decrease surface velocity and surface profile variations by imposing two strong static ruler-shaped magnetic fields oriented vertically near the narrow faces [109][110][111]. The flow velocity up the narrow face is predicted to become slower and more uniform with vertical EMBr [110]. This is proposed to be useful for high-speed thin-slab mold casting, to avoid excessive surface flow problems.…”

“…This is proposed to be useful for high-speed thin-slab mold casting, to avoid excessive surface flow problems. If the flow has a double-roll pattern with a downward jet, then the vertical ruler field is predicted to reduce surface velocity more than a horizontal single-ruler EMBr field [109,110], as shown in Figure 11.…”

“…vertically near the narrow faces [109][110][111]. The flow velocity up the narrow face is predicted to become slower and more uniform with vertical EMBr [110]. This is proposed to be useful for highspeed thin-slab mold casting, to avoid excessive surface flow problems.…”