Application of Silicon Carbide Reaction Sintering

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The silicon carbide reaction sintering process is to add silicon powder and carbon (graphite, carbon black, etc.) to silicon carbide, and burn it at 1450℃ to make the silicon powder and carbon react to form low-temperature β-SiC, which combines the original silicon carbide particles As a result, the SiC products prepared by this process have good performance and greater strength. Since the product generally contains 8%-15% free silicon and a small amount of free carbon, the operating temperature is generally lower than 1400°C. Its thermal conductivity and impact resistance are good, but its strength, hardness, and corrosion resistance are poor. Reaction sintered silicon carbide products have almost the same size before and after sintering. Therefore, they can be processed into any shape and size after forming, which is especially suitable for large-scale and complex-shaped products.

Silicon carbide reaction sintering is a high-tech industrial ceramic material with high high temperature strength, strong oxidation resistance, strong acid and alkali corrosion resistance, good thermal stability, high thermal conductivity, hardness second only to diamond, and high wear resistance , Has been processed into silicon carbide flame nozzle burner sleeve, silicon carbide beam roller, silicon carbide cold air tube, silicon carbide radiant tube, silicon carbide preheating tube wind guide sleeve, silicon carbide sandblasting nozzle, silicon carbide desulfurization nozzle , Silicon carbide wear-resistant linings and other wear-resistant, high-temperature, and corrosion-resistant products are widely used in various industries such as electric power, steel, ceramics, high-temperature equipment, petroleum, chemical, environmental protection, machinery manufacturing, etc. Widely recognized.

1. Silicon Carbide Reaction Sintering Flame Nozzle Burner Sleeve

Silicon carbide burner nozzle cover: This product has high high temperature strength, oxidation resistance, abrasion resistance, rapid cold and rapid heat resistance, long-term high temperature use without breaking or deformation, and can effectively control the temperature balance in the kiln. It has been widely used It is applied to fire-spray kiln furniture of daily-use porcelain, sanitary porcelain, architectural ceramics and other high-temperature kilns such as (roller kiln, tunnel kiln, shuttle kiln, etc.).

2. Silicon Carbide Reaction Sintering Desulfurization Nozzle

The reaction sintered silicon carbide desulfurization nozzle is a key component of thermal power plants, large boilers, and complete sets of desulfurization and dust removal equipment. The localization of silicon carbide desulfurization nozzles has replaced imported products and filled the domestic gap. This product has high strength, high hardness and strong resistance. Corrosion, severe abrasion, high temperature resistance and other excellent performance, have an extraordinary service life under harsh conditions, the common types are mainly spiral nozzles and vortex nozzles.

2.1. Silicon carbide spiral desulfurization nozzle

When the nozzle is rotated, part of the outer layer of liquid hits the spiral surface at a certain angle on the nozzle, thereby changing the spray direction and leaving the nozzle. The angle between the streamline of the spray surface of the different layers of cones and the center (helix angle) gradually decreases, and the liquid is entering from There is no obstruction in the passage from the nozzle cavity to the outlet. The spray area of ​​a spiral nozzle is a solid cone fog field composed of a series of continuous concentric hollow cones. The spiral series nozzles can provide 60, 90 Different spray angles such as, 120 degrees, so as to meet different engineering needs, and still have a high absorption efficiency under the lowest pressure, which has been universally recognized by the desulfurization system. The streamlined design of the nozzle cavity from the inlet to the outlet minimizes the drag coefficient. Therefore, the spiral nozzle has the advantage of good atomization effect, but the disadvantage is that it is easy to foul and block.

2.2. Silicon carbide swirl nozzle

Silicon carbide vortex nozzles are divided into silicon carbide unidirectional hollow cones and solid cones, silicon carbide unidirectional double-headed high-efficiency nozzles and silicon carbide bidirectional double-headed nozzles. The nozzle sprays at right angles to the inlet direction, integral grouting, without internal separation parts, the spray shape is hollow cone or solid cone, the spray area is annular, there are multiple spray angles and flow designs, and the spray of the vortex nozzle is small. And even and the vortex channel is large, the nozzle is not easy to be clogged.

When working, the high-pressure pump is used to make the slurry obtain a higher pressure, and enter the swirling chamber of the nozzle from the tangential inlet. The slurry obtains rapid rotating motion in the swirling chamber. According to the principle of conservation of rotational momentum, the slurry accelerates and rotates to form a rotating annular film. , The static pressure energy of the slurry is transformed into the kinetic energy of the rotating slurry moving forward at the nozzle, and the slurry film stretches and becomes thinner when ejected from the nozzle, and finally splits into small droplets, thereby forming a tapered slurry mist.

3. Reaction Sintered Silicon Carbide Beam

Reaction sintered silicon carbide beam shuttle kiln, tunnel kiln, double-layer roller kiln, industrial furnace and other high temperature kiln sintered products weighing frame support, with good high temperature oxidation resistance, bending resistance, thermal shock resistance , Long-term use is not easy to deform and other characteristics.

4. Reaction Sintered Silicon Carbide Rollers, Cold Air Ducts

The reaction sintered silicon carbide roller and cold air tube have good thermal stability, thermal shock resistance, oxidation resistance, high temperature creep resistance, resistance to rapid cold wind impact at high temperatures, long-term use, and non-deformation and bending. The service life is much longer than other materials. , Has been widely used in the high temperature quenching section of high temperature roller kiln in construction ceramic roller kiln, lithium battery and other industries.

5. Silicon Carbide Radiant Tube, Preheat Tube Heat Exchanger

Silicon carbide radiant tubes have good thermal conductivity and are used in the return processing production line of the iron and steel metallurgical industry, and are suitable for heat conduction devices and heat dissipation devices under high temperature, high corrosion, and abrasion conditions. Silicon carbide heat exchangers and preheating tubes are a new type of tubular high-temperature heat recovery device, which can be widely used in metallurgy, machinery, building materials, chemical industries and other industries to directly recover the high temperature of 850-1400℃ discharged from various industrial kilns The flue gas waste heat is used to obtain high-temperature combustion-supporting air or process gas.

This product has good heat conduction performance, is used in the annealing treatment production line of the iron and steel metallurgical industry, and is suitable for heat conduction devices and heat dissipation devices under high temperature, high corrosion, and high wear conditions.

6. Silicon Carbide Frame Energy-saving Kiln Furniture

Silicon carbide frame energy-saving kiln furniture is a high-temperature load-bearing structural frame suitable for tunnel kilns, shuttle kilns, some roller kilns and other kilns. The interspersed combination of beams, secondary beams or ultra-thin kiln plates, the height of the product layers can be adjusted freely, and the frame structure greatly reduces the overall weight of the kiln furniture, is convenient to operate, and greatly increases the loading density of the product, and the silicon carbide is sintered due to reaction The excellent thermal conductivity of the material makes the silicon carbide frame energy-saving kiln furniture save at least 20% more energy than the traditional kiln furniture, and the service life is greatly increased. At present, the reaction sintered silicon carbide frame energy-saving kiln furniture has been used in daily-use porcelain, sanitary ceramics, and high-pressure It is widely used in the ceramic industry such as electric porcelain.

7. Silicon Carbide High Wear-resistant Lined Composite Pipe

Silicon carbide wear-resistant lining: reaction sintered silicon carbide wear-resistant lining has high chemical corrosion resistance, with a Mohs hardness of about 9.6, which is second only to diamond with high wear resistance, high temperature resistance and good self-lubricating performance , Its low friction coefficient, light weight and high strength. The service life is several times that of general wear-resistant materials. It has been widely used in cyclone linings, mines, metallurgical power and other wear-resistant and corrosion-resistant pipe linings.