作者：Kentaro IWAMOTO and Jyouki YOSHITOMI

作者单位：

刊名：Journal of the Technical Association of Refractories, Japan

ISSN：

出版年：2013-08-01

卷：33

期：3

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止页：

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语种：英文

关键词：Upper nozzle. Oxygen lance corrosion. Metal addition

内容简介

Recently, because of the increase in the service life of sliding nozzle plates, by improvements in resistance against spalling. oxidation, and erosion it has become necessary to increase the service life of the upper nozzles as well. The upper nozzle is exposed to sever operation environments, namely. 1) chemical corrosion by slag. 2) physical erosion by the flow of molten steel, and 3) by oxygen lancing for removing adhered materials after the casting, or the removal of residual steel after slagging-off. furthermore. 4) this repeated and continuous casting causes damage by thermal spalling. because it generates a thermal variation with repeated cooling and heating, and 5) the damage from structural spalling happens in the reaction layer formed by the permeation of slag. etc. Especially, the inner sin-face of the upper nozzle is damaged from the oxygen lancing used for removing residual slag and steel by the melting and cutting method, which applies high temperatures generated from iron powder or iron rod reacting to pure oxygen.