Method for prolonging service life of oxygen lance nozzle by reducing slag adhering to oxygen lance nozzle

Abstract

The invention discloses a method for prolonging the service life of an oxygen lance nozzle by reducing slag adhering to the oxygen lance nozzle. The method includes the steps that organic dirt on the surface of the oxygen lance nozzle is removed in a vapor degreasing and purging manner, and then a clean oxygen lance nozzle is obtained; the clean oxygen lance nozzle is fixed to a fixing frame to be preheated, wherein the preheating temperature is 573 K-723 K; spraying is performed on the surface of the oxygen lance nozzle through a plasma gun, wherein the maximum power of the plasma gun is 80 kW, the maximum current of the plasma gun is 1000 A, and the no-load voltage of the plasma gun is 80 V; and boron nitride particles are fed into a powder feeding port of the plasma gun through argon and sprayed to the surface of the oxygen lance nozzle, and then an oxygen lance nozzle with a boron nitride coating is obtained. Boron nitride and the copper oxygen lance nozzle are combined to form the boron nitride coating which is resistant to high temperature and corrosion and does not react with steel slag, so that the amount of slag adhering to the oxygen lance nozzle in the converter steelmaking process is reduced, and the service life of the oxygen lance nozzle is prolonged.

Description

technical field [0001] The invention relates to a maintenance method for an oxygen lance nozzle used in converter steelmaking, in particular to a method for prolonging the service life of an oxygen lance nozzle by reducing sticky slag in the oxygen lance nozzle. technical background [0002] In the middle and later stages of the converter blowing process, due to the low oxygen lance position or the high temperature of the molten pool, the iron oxide content in the slag decreases sharply, and the fluidity of the slag becomes poor, which in turn makes the melted or partially melted slag become cohesive. Under the impact of the air flow, the molten steel splash easily adheres to the end surface of the oxygen lance nozzle and accumulates on the oxygen lance nozzle, which shortens the life of the oxygen lance nozzle, affects the operation rate of the converter, and increases the labor intensity of workers. When the nozzle sticks to slag, it is easy to wear and corrode the nozzle ...

AI Technical Summary

Problems solved by technology

Although this invention can reduce the slag sticking phenomenon of the oxygen lance in the steelmaking process to a certain extent, the operation is complicated and more raw materials are used. Although a protective layer can be formed on the slag-retaining wall of the converter steelmaking and the surface of the oxygen lance, Most of the steel slag and molten steel stuck in the work can fall off by itself, but the remaining steel slag and molten steel together with the protective layer need to be shoveled off manually with a drill, which is easy to damage the nozzle of the oxygen lance and cannot achieve the purpose of protecting the nozzle of the oxygen lance

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