Investigation on Nozzle Blockage during Continuous Casting of Steel

钢水连铸是近60年来炼钢领域最重大的技术革新之一。然而，保护钢材在转移过程中不被大气氧化的耐火浸入式水口堵塞或堵塞是一个严重的问题，这对浇注操作和铸件质量都有不利影响。与Gerdau Whitby合作，这项拟议的研究旨在表征堵塞喷嘴壁上沉积的材料，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是美洲生产长钢特种产品的领先公司，也是世界主要供应商之一。Gerdau的北美业务部门通过钢铁厂、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。位于安大略省惠特比的这家钢铁厂是在加拿大运营的三家Gerdau钢厂之一，拥有约500名员工。Gerdau Whitby将每年约24万辆旧车的废金属转化为特殊钢材产品，包括梁和桩、螺纹钢、特殊钢筋和线材。该项目的目标可定义如下：1)使用先进的表征技术研究喷嘴堵塞的成分。2)将结果与在炼钢和铸造过程中不同阶段获得的钢样中的夹杂物联系起来。3)评价改变钢水成分、浇注温度、耐火材料和钢水流量等操作参数以消除水口堵塞问题的相对有效性。该项目的总体目标是创造一个新的知识库，促进学术界和工业部门之间的技术转让，从而改善炼钢工艺、提高产品质量和缩短处理时间。另一个好处是对学生进行冶金化学和材料特性方面的培训，这反过来又将促进加拿大各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.