A long-life service method for powder-bottom-injecting converter based on collaborative hot replacement of furnace bottom and bottom purging brick belongs to the field of steelmaking technologies using powder-bottom-injecting converters. According to equipment characteristics, process characteristics, and erosion characteristics of the powder-bottom-injecting converter, the design, arrangement, installation, use, maintenance, and replacement of the bottom purging/powder injection bricks are systematically optimized and improved, a technology of automatically detecting the erosion height of bottom purging bricks is adopted, and hot replacement of bottom purging/powder injection bricks and hot replacement of the converter furnace bottom are used collaboratively, which not only can prolong the service life of a single bottom purging/powder injection brick, but also can greatly prolong the overall life of the powder-bottom-injecting converter from 1000-3000 heats in the prior art to 6000-10000 heats. Hence, the life of the powder-bottom-injecting converter is as long as that of a conventional converter.

A long-life service method for powder-bottom-injecting converter based on collaborative hot replacement of furnace bottom and bottom purging brick belongs to the field of steelmaking technologies using powder-bottom-injecting converters. According to equipment characteristics, process characteristics, and erosion characteristics of the powder-bottom-injecting converter, the design, arrangement, installation, use, maintenance, and replacement of the bottom purging/powder injection bricks are systematically optimized and improved, a technology of automatically detecting the erosion height of bottom purging bricks is adopted, and hot replacement of bottom purging/powder injection bricks and hot replacement of the converter furnace bottom are used collaboratively, which not only can prolong the service life of a single bottom purging/powder injection brick, but also can greatly prolong the overall life of the powder-bottom-injecting converter from 1000-3000 heats in the prior art to 6000-10000 heats. Hence, the life of the powder-bottom-injecting converter is as long as that of a conventional converter.

A refining vessel for high-temperature melt includes a refractory for gas blowing nozzle that includes a central refractory embedded with metal tubules, and an outer refractory circumferentially surrounding the central refractory. The refractory for gas blowing nozzle has a horizontal projection on which a minimum radius of an imaginary circle encompassing all the metal tubules embedded in the central refractory is R (mm), wherein the central refractory has an outline that falls between one circle that is concentric with the imaginary circle and has a radius of R+10 mm, and another circle that is concentric with the imaginary circle and has a radius of R+150 mm. The central refractory is formed of a MgO—C refractory having a carbon content of 30 to 80 mass %, and the outer refractory is formed of a MgO—C refractory having a carbon content of 10 to 25 mass %.

A refining vessel for high-temperature melt includes a refractory for gas blowing nozzle that includes a central refractory embedded with metal tubules, and an outer refractory circumferentially surrounding the central refractory. The refractory for gas blowing nozzle has a horizontal projection on which a minimum radius of an imaginary circle encompassing all the metal tubules embedded in the central refractory is R (mm), wherein the central refractory has an outline that falls between one circle that is concentric with the imaginary circle and has a radius of R+10 mm, and another circle that is concentric with the imaginary circle and has a radius of R+150 mm. The central refractory is formed of a MgO—C refractory having a carbon content of 30 to 80 mass %, and the outer refractory is formed of a MgO—C refractory having a carbon content of 10 to 25 mass %.

A gas injection nozzle refractory with one or more gas injection small metal tubes buried therein has improved durability. The gas injection nozzle refractory includes a MgO-C central refractory with a small metal tube buried therein, and a MgO-C peripheral refractory surrounding the central refractory. The central refractory on a plane of the gas injection nozzle refractory has an external shape of a circle with a radius in the range of R+10 to R+150 mm concentric with a virtual circle with a minimum radius surrounding all buried small metal tubes, R mm being a radius of the virtual circle.

A gas injection nozzle refractory with one or more gas injection small metal tubes buried therein has improved durability. The gas injection nozzle refractory includes a MgO-C central refractory with a small metal tube buried therein, and a MgO-C peripheral refractory surrounding the central refractory. The central refractory on a plane of the gas injection nozzle refractory has an external shape of a circle with a radius in the range of R+10 to R+150 mm concentric with a virtual circle with a minimum radius surrounding all buried small metal tubes, R mm being a radius of the virtual circle.

A socket installation structure of a refractory article is designed to prevent gas leakage therein. A first flange is provided between an outward end and an inward end of a socket, and a face of the first flange on the side of an inward end thereof is bonded to an article body of the refractory article through a sealing material. Further, a face of the first flange on the side of an outward end thereof faces a metal plate disposed around the outward end or a second flange provided on the side of the outward end, through a low thermally-conductive material layer made of a low thermally-conductive material having a thermal conductivity at room temperature of 40 (W/(m.Math.K)) or less.

A blowing control method for maintaining a mushroom head of a bottom-blowing nozzle converter is disclosed. Considering the actual state of the mushroom head at the end of the bottom-blowing nozzle tip, the real-time molten steel overheating change during the blowing process, the process requirements of different stages of blowing conversion, and the macroscopic heat balance of the converter, the oxygen-carbon dioxide-lime powder blowing parameters of the inner tube of the bottom-blowing nozzle are dynamically adjusted during the converter smelting process of the bottom-blowing nozzle converter so as to control the cooling intensity, thus achieving precise control of the size of the mushroom head. The present invention maintains the basic stability of the size of the mushroom head at the end of the bottom-blowing nozzle tip, avoiding nozzle blockage caused by an oversized mushroom head and rapid erosion of the nozzle caused by an undersized mushroom head.

A gas injection nozzle refractory with one or more gas injection small metal tubes buried therein has improved durability. The gas injection nozzle refractory includes a MgO—C central refractory with a small metal tube buried therein, and a MgO—C peripheral refractory surrounding the central refractory. The central refractory on a plane of the gas injection nozzle refractory has an external shape of a circle with a radius in the range of R+10 to R+150 mm concentric with a virtual circle with a minimum radius surrounding all buried small metal tubes, R mm being a radius of the virtual circle.

A gas injection nozzle refractory with one or more gas injection small metal tubes buried therein has improved durability. The gas injection nozzle refractory includes a MgO—C central refractory with a small metal tube buried therein, and a MgO—C peripheral refractory surrounding the central refractory. The central refractory on a plane of the gas injection nozzle refractory has an external shape of a circle with a radius in the range of R+10 to R+150 mm concentric with a virtual circle with a minimum radius surrounding all buried small metal tubes, R mm being a radius of the virtual circle.