Method of prolonging service life of oxygen lance of converter

Abstract

The invention relates to a method of prolonging the service life of an oxygen lance of a converter. The method comprises the following steps: carrying out treatment on bottom end surface of a spray head of the oxygen lance and treatment on side wall of an oxygen lance body, coating a high-temperature-resistant antioxidant coating to the bottom end surface of the spray head of the oxygen lance, carrying out induction heating or flame heating treatment on the end surface, spraying a first layer with a coal gas type flame high pressure spray gun, and spraying a second layer with an oxygen-acetylene flame high pressure spray gun; derusting the side wall of the gun body to a range 2-10 m far from the bottom end surface by taking the bottom end surface of the spray head of the oxygen lance as the starting point, and then smearing a coating; and spraying boron nitride powder to the coating by using the oxygen-acetylene flame high pressure spray gun. The method has the advantages that the service life of the oxygen lance is prolonged, and the labor intensity of workers is alleviated to a great extent; the deslagging treatment time as slag is attached to the oxygen lance is saved, the blowing rhythm is more compact, the effective operating efficiency of the converter is increased, and the output of steel is improved.

Description

technical field [0001] The invention relates to a method for increasing the service life of a converter oxygen lance. Background technique [0002] The oxygen lance is the key equipment for converter steelmaking, especially the end bottom of the oxygen lance bears a very high heat load, and its value is 2.72×10 6 ~3.60×10 6 kJ / (m 2 .h), while the heat load on the side wall is relatively small, only 0.014×10 6 kJ / (m 2 .h), equivalent to 1 / 200 of the end bottom. In the actual blowing process, the damage to the oxygen lance mainly occurs at the bottom end surface of the nozzle and the side wall about 2m away from the lance head. The damage to the bottom surface of the oxygen lance nozzle is mainly caused by the thermal erosion of the high-temperature slag and the metal droplets dispersed in the slag. The damage to the side wall of the lance head is mainly due to the fact that the side wall of the lance head cannot fall off after being bonded with the slag-steel mixture, a...

AI Technical Summary

Problems solved by technology

Although the patent combines boron nitride and copper oxygen lance nozzles to form a boron nitride coating, it uses the characteristics of boron nitride coating not only high temperature resistance, corrosion resistance, and no reaction with steel slag, thereby reducing the cost of the converter steelmaking process. The amount of slag sticking to the nozzle of the oxygen gun, but because the sprayed boron nitride particles are only attached to the surface of the nozzle, the erosion resistance is very poor, and the coating will be directly washed away by the high-temperature slag and air flow during use, which cannot to the desired effect

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