Investigation on Nozzle Blockage during Continuous Casting of Steel

钢水连铸是近60年来炼钢领域最重要的技术创新之一。然而，在转移过程中保护钢免受大气氧化的耐火材料浸入式喷嘴的堵塞或堵塞是一个严重的问题，因为它对铸造操作和铸造产品的质量产生不利影响。与Gerdau Whitby合作，提出的研究旨在表征沉积在堵塞喷嘴壁上的材料，调查这些材料的可能来源，并评估操作参数对堵塞形成的影响。Gerdau是美洲长钢特种产品生产的领先公司，也是世界主要供应商之一。Gerdau的北美业务部门通过钢厂、回收业务和下游加工设施的垂直整合网络，为建筑、汽车、农业、房地产和能源市场提供服务。这家位于安大略省惠特比的钢铁厂是格尔道在加拿大运营的三家钢厂之一，拥有约500名员工。Gerdau Whitby每年将约24万辆旧车的废金属转化为特种钢材产品，包括横梁和桩、钢筋、特种钢筋和线材。该项目的目标可以定义如下：1)使用先进的表征技术研究喷嘴堵塞成分。2)将结果与炼钢和铸造过程中不同阶段获得的钢样中发现的夹杂物联系起来。3)评价修改操作参数的相对有效性，如钢成分、铸造温度、耐火材料和钢液流量，以消除喷嘴堵塞问题。该项目的总体目标是建立一个新知识库，促进学术界和工业部门之间的技术转让，从而改进炼钢工艺，提高产品质量，缩短处理时间。另外一个好处是对学生在冶金化学和材料特性方面的培训，这反过来将促进加拿大组织在科学和工程方面的卓越表现。

Continuous casting of molten steel is one of the most significant technological innovations in the field ofsteelmaking within the last 60 years. However, blockage or clogging of the refractory submerged entry nozzlewhich protects the steel from atmospheric oxidation during transfer processes is a serious problem due to theadverse effects on the casting operation and quality of the cast product. In collaboration with Gerdau Whitby,the proposed study is aimed at characterizing materials deposited on the walls of blocked nozzles, investigatingthe possible sources of these materials, and evaluating the effect of operational parameters on the formation ofclogging. Gerdau is the leading company in the production of long steel specialty products in the Americas andone of the world's major suppliers. Gerdau's North American business divisions serve the construction,automotive, agricultural, real estate and energy markets through a vertically integrated network of steel mills,recycling operations, and downstream processing facilities. The steel plant in Whitby, Ontario is one of threeGerdau mills operating in Canada and employs approximately 500 people. Gerdau Whitby transforms scrapmetal from about 240,000 old cars a year into special steel products including beams and piling, rebar, specialbar and wire rod. The objectives of this project can be defined as follows: 1) Investigate nozzle blockageconstituents using advanced characterization techniques. 2) Relate the results to the inclusions found in steelsamples obtained at different stages during the steelmaking and casting processes. 3) Evaluate the relativeeffectiveness of modifying operational parameters such as steel composition, casting temperature, refractoriesand liquid steel flow, in order to eliminate nozzle blockage problems. The overall aim of the project is togenerate a bank of new knowledge and facilitate technology transfer between academia and the industrial sectorthat will result in improved steelmaking processes, higher quality product and reduced treatment time. Anadditional benefit will be the training of students in metallurgical chemistry and materials characterizationwhich in turn will boost excellence in science and engineering within Canadian-based organizations.