Reaction sintering silicon carbide ceramic sintering

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Reaction sintered silicon carbide is a process that the raw materials (silicon carbide powder, graphite, carbon black, binder and various additives) pass through the solid phase at 1720 ℃, and chemical reactions take place between the liquid phase and the gas phase. At the same time, densification and synthesis of specified components are carried out to obtain the predetermined sintered body. Reaction sintered silicon carbide is a kind of high-tech industrial ceramic material, which has high temperature strength, strong oxidation resistance, strong acid and alkali corrosion resistance, good thermal stability, high thermal conductivity, and high wear resistance after diamond. Now it has been processed into silicon carbide burner sleeve, silicon carbide beam roller, silicon carbide cold air pipe, silicon carbide radiation pipe, silicon carbide preheating pipe air guide sleeve , silicon carbide sandblasting nozzle, silicon carbide desulfurization nozzle, silicon carbide wear-resistant lining and other high-temperature, wear-resistant, corrosion-resistant products are widely used in power, steel, ceramics, high-temperature furnace, mine, coal, alumina, petroleum, chemical industry, environmental protection wet desulfurization, mechanical manufacturing and other industries, and widely recognized by the community.

I. reaction sintering silicon carbide burner sleeve
Silicon carbide burner set: the product has high temperature strength, oxidation resistance, wear resistance, cold and heat resistance, long-term high temperature use without fracture and deformation, and can effectively control the temperature balance in the kiln. It has been widely used in high-temperature kilns such as household porcelain, sanitary porcelain, building ceramics, etc. (roller kiln, tunnel kiln, shuttle kiln, etc.).

II. Reaction sintering silicon carbide desulfurization nozzle
Reaction sintering silicon carbide desulfurization nozzle is the key component of thermal power plant, large boiler, desulfurization and dedusting complete set of equipment. The localization of silicon carbide desulfurization nozzle has replaced the imported product, filling the domestic blank. The product has high strength, high hardness, strong corrosion resistance, severe wear, high temperature resistance and other excellent performance, and has extraordinary service life under severe conditions. The common types are as follows: Spiral nozzle and swirl nozzle are the main.

1. Silicon carbide spiral desulfurization nozzle
Working principle of spiral nozzle: as the liquid with a certain pressure and speed flows through the spiral nozzle from top to bottom, the outer part of the liquid impacts the spiral surface with a certain angle on the nozzle, so as to change the spray direction and leave the nozzle, the angle between the streamline and the center of the jet surface of different cone layers (spiral angle) decreases gradually, and there is no liquid in the channel from entering the nozzle cavity to the outlet There is no obstruction. The spray area of a spiral nozzle is a solid conical fog field composed of a series of continuous concentric axis hollow cones. The spiral series nozzles can provide different spray angles of 60, 90, and 120 degrees, so as to meet different engineering requirements, and at the lowest pressure, they still have high absorption efficiency and have been generally recognized by the desulfurization system.
The streamlined design of the nozzle cavity from the inlet to the outlet reduces the resistance coefficient to the minimum, so the advantages of the spiral nozzle are good atomization effect, and the disadvantages are easy to scale and block.

2. Silicon carbide swirl nozzle
Silicon carbide swirl nozzle is divided into silicon carbide one-way hollow cone, solid cone, silicon carbide one way double head high efficiency nozzle and silicon carbide bidirectional double nozzle. Swirl nozzle is the swirl chamber where the slurry enters the nozzle from tangential direction, and then the right angle jet hole is sprayed out. The whole grouting is formed without internal parts leaving, and the spray shape is hollow conical or solid cone. The spray area is annular, and there are various spray angles and flow designs. The swirl nozzle has small spray and uniform swirl channel, and the nozzle is not easy to jam.

During operation, the high-pressure pump is used to make the slurry obtain higher pressure and enter the swirl chamber of the nozzle from the tangential inlet. The slurry obtains rapid rotation movement in the swirl chamber. According to the conservation principle of rotation momentum moment, the slurry accelerates rotation to form a circular membrane around the rotation. The static pressure of the slurry can be converted into the kinetic energy of the rotating slurry moving forward at the nozzle. When the slurry is ejected from the nozzle, the slurry membrane will stretch and thin, and finally It splits into small droplets to form a conical slurry mist.

III. reaction bonded silicon carbide beam
Reaction Sintering SiC beam shuttle kiln, tunnel kiln, double roller kiln, industrial furnace and other high temperature furnaces.
The weighing frame support of sintered products has the characteristics of high temperature oxidation resistance, high bending strength, good thermal shock resistance, long-term use and long service life.

IV. reaction sintering silicon carbide roller and cold air pipe
Reaction sintered silicon carbide roller and cold air pipe have good thermal stability, thermal shock resistance, oxidation resistance, high temperature creep resistance, cold blast resistance under high temperature, long-term use is not easy to deform and bend, and their service life is far longer than other materials. They have been widely used in the high-temperature and cold section of high-temperature roller kilns in construction ceramics roller kilns, lithium batteries and other industries.

V. silicon carbide radiant tube and preheating tube heat exchanger
Silicon carbide radiant tube has good thermal conductivity, which is used in the production line of return processing in iron and steel metallurgy industry. It is also suitable for the heat conduction device and heat dissipation device under the condition of high temperature, high corrosion and wear.

Silicon carbide heat exchanger and preheating tube are a new type of tubular high-temperature heat recovery device, which can be widely used in metallurgy, machinery, building materials, chemical industry and other industries. They can directly recover the 850-1400 ℃ high-temperature flue gas waste heat discharged by various industrial kilns to obtain high-temperature combustion supporting air or industrial gas.

The product has good heat conduction performance, and is used in annealing production line of iron and steel metallurgy industry. It is also suitable for heat conduction device and heat dissipation device under the condition of high temperature, high corrosion and high wear.

Vi. silicon carbide frame type energy-saving kiln
Silicon carbide frame type energy-saving kiln furniture is a high-temperature load-bearing structure frame suitable for tunnel kiln, shuttle kiln, some roller kilns and other kilns. It has high-temperature strength and good thermal conductivity. The frame structure adopts the combination of porous column, main crossbeam, secondary crossbeam or ultra-thin kiln plate. The product layer height can be adjusted freely, and the frame structure greatly reduces the overall kiln furniture The weight is convenient to operate and greatly increases the loading density of the product. Due to the excellent thermal conductivity of reaction sintered silicon carbide, the energy-saving kiln furniture of silicon carbide frame type is at least 20% more energy-saving than the traditional kiln furniture, and its service life is greatly increased. At present, reaction sintered silicon carbide frame type energy-saving kiln furniture has been widely used in the ceramic industry such as daily ceramics, bathroom ceramics, high-voltage electric ceramics, etc Extensive application.

VII. High wear resistant silicon carbide lined composite pipeline
Carborundum wear-resistant lining: reaction sintered carborundum wear-resistant lining has high chemical corrosion resistance, Mohs hardness is about 9.6, the hardness is next to diamond with high wear resistance, high temperature resistance and self-lubricating performance, low friction coefficient, light weight and high strength. Its service life is several times of that of general wear-resistant materials. It has been widely used in hydrocyclone lining, mines, metallurgy and electrowinning Lining of wear-resistant and corrosion-resistant pipe fittings