Study On Flow Field Optimization Of Mould Of Wide-Slab Continuous Casting By Water-modeling Experiments

In recent years,with the development of continuous casting technology. Highly efficient continuous casting technology become one of develop orientations of continuous casting technology. Under persisting in precondition of slab quality, the development of slab caster high efficiency should improve caster operating rate, reduce steel breakout and facility fault, Improve caster productivity. Therefore resolving the key problem of affecting slab quality and process smooth operation in slab mould is very important to promote high efficient continuous casting productivity and development of continuous casting technology in our country. At the moment, Domestic slab caster trend to change wide side to wider and change narrow side to more narrow. The phenomena of shell formation at bath level in mould often appear at the process of continuous cast. It affects slab quality and process smooth operation and constrains the development of slab caster high efficiency heavily. So to research on causes leading to shell formation at bath level in mould and give the settling train of thought and countermeasures is important significance for promoting process smooth operation and high efficient continuous casting productivity.The archetype of the mould is the wide slab continuous casting mould (cross section size is 23mm×2000mm) in a domestic factory in this paper. A water model research method is performed to study fluid flow action in mould when original SEN is applied. The research designed a new style SEN for the phenomena of shell formation at bath level in mould at the process of continuous cast especially and optimized the SEN structural and operating parameters. The conclusions show that:1) When original SEN is applied, Intensity of pressure that fluid from two lateral out-let apertures of the SEN impact mould narrow side is little, this result in upside reflow in mould weak, bath level in mould is not active, the exchange speed of surface fluid at the bath level in mould is very slow. All of these are the main reasons that lead to shell formation at bath level in mould. What is more, there is a certain bias flow in mould. 2) Many parameters as bottom pattern,angle of out-let aperture,area ratio of out-let aperture and immersion depth influence significantly flow field in mould, the optimized research on field should consider all these parameters comprehensively.3) On the condition of experiments, the optimized the new style SEN structural and operating parameters are that:The bottom pattern is concave bottom, angle of out-let aperture is 15°, area ratio of out-let aperture is 2.20, range of immersion depth is 40～60mm. Area of upside reflow in mould decrease,upside reflow strengthen and bias flow disappear. The comparative ideal field is obtained. The experiment result offer reference for that diminishing shell formation at bath level in mould and promoting slab quality and productive process smooth operation.