In the lining of the converter, the outlet is the channel through which molten steel enters the ladle from the converter. Due to the erosion and oxidation of molten steel at high temperature, the working conditions are harsh, and the service life of the outlet is generally low. In the process of furnace service maintenance, continuous repair or replacement is required, which not only affects the production rhythm, but also directly affects the quality of molten steel. How to extend the service life of the steel outlet has attracted wide attention in the industry.

The commonly used repair materials for the steel outlet of converter mainly include traditional dry spray filler and magnesia chromium castable. Due to the addition of inorganic salts with low melting point, uncertainty of the amount of water added, short mixing time of materials and water, fine particle size and poor spalling resistance, etc., the traditional dry spray supplementary material leads to loose structure and low strength of the material, resulting in short life and difficult to meet the requirements of the converter. Therefore, at present, more magnesium chromium castable is used on site to slow down the damage speed of the steel gate. However, due to the limitation of the hot repair construction conditions of the converter, the magnesium-chromium castable should be manually stirred with a spade, pushed to the furnace with a trolley, and then manually turned into the furnace. Due to the influence of the high temperature of the furnace lining and the inaccuracy caused by long-distance throwing, the castable cannot be completely accurate into the gap between the steel outlet sleeve and the brick. It is necessary to use water pipe flushing brush material to assist, which not only causes hidden damage to the hot brick lining, but also leads to the material is not resistant to high temperature slag erosion, low strength, short service life and other problems, at the same time, because the magnesium chromium castable contains a certain proportion of chromium oxide, seriously polluting the site environment, and has a very bad impact on the health of construction personnel.

This technology can solve the problems such as excessive water addition (up to 30%) of traditional dry spray replenishment material and difficult artificial fine construction of magnesium-chromium castable in high temperature and harsh environment, so that magnesium-free flow material can quickly and accurately flow into and out of the gap between the steel sleeve and the brick, distribute evenly and fill fully, and has the characteristics of dense structure, good bonding performance, high anti-explosion performance. Using steel casing can realize its designed service life, and make the site construction more simple, equipment and safety. In addition, because the artesian material has the characteristics of low water addition (as low as 5%) and high thermal artesian flow, it can greatly shorten the sintering time of the material, and is the first case in the field of converter outlet replacement and repair at home and abroad.