Modelling-based Innovative Feeding Strategy for Beam Blanks Mould Casting Aimed at As-cast Surface Quality Improvement

抄録

Within an investigation focused on effect of casting conditions on steel quality in an industrial beam blanks mould, different nozzle geometries were tested with Computational Fluid Dynamics modelling. The innovative nature of the work consisted in feeding with only one nozzle, whereas two nozzles in the flange-tip zone are commonly used. This configuration has the advantage of a simplified mono-slide gate casting layout, but single nozzle feeding can bring about risks of too high steel velocity in the mould, harmful for shell integrity and meniscus stability.
Having in mind the mentioned constraints, different geometry solutions were checked and, to assess the solutions found, suitable indices were defined, related to flow conditions able to prevent slag entrapment at the meniscus, and hot-spotting at walls, harmful for the solid shell integrity.
The modelling work gave general indications on undesired flow features and guidelines to improve reference conditions, involving number of holes and holes angle, size and shape. For the caster mould and the operating conditions under concern, a solution was found satisfying the indices, and expected to fulfil the quality requests. It consisted of a nozzle with a 50 mm diameter throat, a 50 mm× 60 mm elliptical lateral port inclined 25° downwards and a 20 mm-diameter bottom hole. A water model check with such a nozzle prototype validated the model supporting the solution identified to be used on plant.