(1) Steelmaking system

 The steelmaking system includes equipment such as converters, electric furnaces, out-of-furnace refining furnaces, ladle and tundish. In the electric furnace, dry vibrating material, prefabricated or cast-in-place furnace cover or furnace cover: triangle area and other parts have good results; in converters and electric furnaces, fire-resistant spray coatings are generally used to repair the damage. The methods are as follows: Manual filling, wet, dry or flame spraying and slag splashing to protect the furnace, etc. In converters, slag splashing protection technology is commonly used, and the furnace age can reach more than 10,000 times; there are many types of refining furnaces outside the furnace, and the insertion tube lining of the RH method and DH method degassing device is generally made of high-aluminum refractory casting The material is poured into a whole, and the service life is 20 to 80 times. Ladle and tundish are important ancillary equipment for steelmaking furnaces, as well as thermal equipment that consumes a lot of refractory materials. In the past, the ladle was generally built with fired bricks such as clay refractory bricks, high alumina refractory bricks, semi-silica bricks and wax stone bricks, with a service life of 10 to 70 times. When ladle blowing or continuous ingot casting is used, the age of the ladle drops sharply due to reasons such as high steel temperature and long residence time. Therefore, various countries attach great importance to the development of lining materials, and significant progress has also been made. Anshan Iron and Steel's converter uses 200t ladle, which is lined with aluminum-magnesium castable and self-flowing material, and the ladle age is about 95 and 80 times respectively; Baosteel uses a 300t ladle for converter, which is lined with high-purity aluminum-magnesium castable, and the ladle age is average after repair At about 260 times, the unit consumption of refractory materials is less than 1.78kg; many steel plants in the country use new technology aluminum-magnesium refractory castables for ladle not larger than 100t, and the ladle age is about 90 times, and the cost of casting steel is 5.50~ per ton of steel. 7.50 yuan. The tundish bag lining is made of thermal insulation board or magnesia paint, and the slag barrier is made of mullite, aluminum-magnesium and magnesia refractory castables, which can meet the technical requirements of continuous steel casting. Integral spray gun for refining outside the furnace, used for ladle argon blowing or ladle powder spraying, etc. The part above the slag line is made of high-aluminum refractory castable, and the part from the slag line to the nozzle is made of low-cement corundum refractory castable, which is vibrated to form an integral wrapping lining. Shanghai Baosteel uses this gun to blow argon. The argon blowing time for each furnace is 3 to 5 minutes, and the life of each spray gun is about 50 furnaces, which is 150 to 250 minutes; Shougang is used for powder spraying, and its life is 30 to 55 minutes.

(2) Ironmaking system

The iron system includes sintering, coking, blast furnace and its auxiliary equipment. The ignition furnace of the belt sintering machine is made on-site with refractory plastic and clay combined with refractory castables, or hoisted with *acid refractory castable prefabricated blocks, and its service life is 3 to 6 years. When the linear ignition device is used, the furnace top pressure is more and the furnace working conditions become better. It can be lined with light-weight high-* refractory castables or refractory fibers and their products to obtain better results; coke oven roof insulation Layers, cladding layers and furnace doors are poured with refractory castables. When the furnace head is damaged, spray paint is used to repair. In addition, CDQ equipment also uses heavy or light refractory castables; blast furnaces are ironmaking equipment for continuous production. Small-scale blast furnaces were once hoisted and built with aluminate cement and high-acid high-alumina refractory castable prefabricated blocks, and now they are generally built with resin-bonded aluminum-carbon non-burning bricks. Large-scale blast furnace water walls use silicon carbide castables, furnace bottom cushions and surrounding brick joints use refractory castables and silicon nitride fillers. When the furnace lining is damaged, use refractory press-fittings and refractory spray coatings to repair, in order to extend the service life. Make the furnace age 10 or even 15 years. The taphole of the blast furnace is generally blocked with loose Al2O3-SiC-C gun mud, which can ensure the stable tapping of the taphole and normal operation. The blast furnace tapping hook was originally rammed with refractory ramming material, and the unit consumption of ditch material t iron is about 1.1kg. At present, low-porosity compact refractories are used for casting, and the amount of iron passing through once reaches about 100,000 tons. The cumulative iron passing volume of one generation of ditch age is about 900,000 tons, and the unit consumption of refractory t iron is less than 0.38kg. At the same time, artesian refractory castables and baking-free refractory castables have also been used on the tap hooks of blast furnaces. Hot blast furnaces are key ancillary equipment for ironmaking blast furnaces. The lining of medium and small blast furnace hot blast furnaces is built with refractory castable prefabricated blocks. The burner of the hot blast stove can be built with refractory castable prefabricated blocks or cast on site, and the spherical top is casted with castable for the working lining. The furnace body of the large-scale hot blast stove depends on the furnace shell* a layer of lightweight spray paint with a bulk density of about 1.3g/cm3, and the dome is sprayed with a layer of acid-resistant spray paint to form an overall inner lining, using corundum refractory castables and other materials on site. Pouring has achieved better results; Torpedo-type hot metal ladle and mixing furnace generally use refractory castables partially or completely, and can also be repaired with refractory spray coatings, with better results.

(3) Building materials system

The building materials system includes industrial sectors such as cement, glass and ceramics. The cement kiln lining is made of high-acid high-alumina or magnesia and magnesia-chromium non-burning bricks, with a service life of 6 to 18 months, and unshaped refractory materials are used locally. Large-scale cement plant rotary kilns such as Jidong and Liuzhou use 19*~35* refractory castables. The main varieties are low-cement refractory castables, aluminate cement refractory castables, silicon carbide refractory castables and heat insulation Castables, etc.; in the glass industry, the tin bath on the float glass production line is made of refractory castables. In addition, when the glass tank kiln is damaged, it is repaired with siliceous repair material. When building a new tank kiln, generally use silicon-based heat-insulating castables; kilns used in the ceramic industry sometimes use silicon carbide-based refractory castables and light-weight refractory castables.

(4) Steel rolling system

There are many types and large quantities of industrial furnaces in the steel rolling system, and the operating temperature is generally below 1400 ℃, all of which are flame furnaces. The kilns of the system can be lined with unshaped refractory materials, and good economic effects have been achieved. The steel rolling heating furnace is lined with refractory plastic and has a long service life. For example, the large-scale walking beam heating furnace of Wuhan Iron and Steel has been used for more than 25 years and is still in use. The furnace lining is poured integrally with clay combined with refractory castables, and the service life is generally 4 to 10 years. For the regenerative heating furnace, the micro-expansion refractory castable should be used as the lining, which has been used for more than 2 years and is intact. Forged steel heating furnaces generally operate intermittently, with large temperature fluctuations and vibrations. They are lined with bricks and used for 2 to 5 months. It can be used for more than 2 years with adhesive and refractory castables. It is well known that the operating temperature of steel rolling furnaces is less than 1400℃ and intermittent operation, domestic and foreign production practice has proved that the lining material should be Al2O3≤65*, and the compressive strength after drying and 1400℃ firing is 20-25Mpa and not less than 60Mpa respectively, which can achieve the purpose of longevity. Because refractory castables with high aluminum content and high strength have poor thermal shock resistance and are easy to peel and crack during use, which affects their life.

(5) Other industrial systems in the petrochemical industry

Tubular heating furnaces use lightweight refractory castables with a bulk density of 0.5~1.0g/cm3, which are applied by hand painting or spraying, and the service life is about 5 years. The use of refractory spray paint to build the lining has also achieved better results. Unshaped refractories are also widely used in platinum reformers and ethylene plants. In particular, wear-resistant and refractory castables have been used in platinum reforming devices, and the heat-resistant steel tortoise shell net system can be eliminated, and its lifespan has also been improved. The lining of various reforming furnaces, the use temperature is 600~1500℃, generally use aluminate cement refractory castable, low cement refractory castable and corundum castable, etc. The service life is 3~6 years; in the non-ferrous metallurgy industry, lead For thermal equipment such as zinc airtight blast furnace, flash furnace, electrolytic cell and rolling heating furnace, unshaped refractory lining is used locally. *Recently, anti-permeable refractory castables are widely used in aluminum reduction cells, and satisfactory results have been achieved; on the lining of steam boilers, the use of unshaped refractory materials is the earliest and *common. Generally, aluminate cement heavy or light refractory castables are used, with a service life of about 10 years. The high-aluminum, corundum and SiC-based refractory castables and refractory plastics used in fluidized bed power boilers have high strength and good wear resistance, which meet the design and use requirements. In addition, unshaped refractory materials are also used in machinery, refractory and garbage incineration industries, and have achieved good results. Friends from all walks of life are welcome to negotiate business and order products.