SiC Swirl Nozzle

RBSiC (SiSiC) desulphurization spray nozzles are the key parts of the flue gas desulphurization system in power generations and large boiler.

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SiC Swirl Nozzle

RBSiC (SiSiC) desulphurization spray nozzles are the key parts of the flue gas desulphurization system in power generations and large boiler.

Reaction Boned Silicon Carbide(RBSiC or SiSiC) ceramics adopt slip-casting technology. The Ceramics have high strength and excellent hardness, wear, corrosion resistance, oxidization resistance and thermal shock resistance, etc. It’s one of the most popular refractory ceramics. It can be made to beams, rollers, cooling air pipes, thermal couple protection tubes, sealing parts and special shaped parts.

They have been installed in the FGD system of many power generations and large boiler.
What I bring to you today is the knowledge about the characteristics of SiC vortex nozzle. I hope it will be helpful to you.

SiC Swirl Nozzle

At present, there are two series silicon carbide products of pressureless sintering silicon carbide (SSIC) and reaction sintering silicon carbide (SISIC), which are widely used in mining, metallurgy, chemical industry, electric power, petroleum, furnace, machinery, steel, energy, environmental protection, building materials, semiconductor, aerospace and other fields. Compared with reaction bonded silicon carbide, pressureless sintered silicon carbide has higher purity, better mechanical properties, more prominent corrosion resistance(Resistant to strong acid and alkali corrosion, It is also the only ceramic material which can resistant to hydrofluoric acid corrosion), higher wear resistance, because of there’s no free silicon in the material. It can be used longer service life in environments which other materials not meet.

Silicon carbide (SiC) is a lightweight ceramic material with high strength properties comparable to diamond. It has excellent thermal conductivity, low thermal expansion, and is resistant to acid corrosion. Silicon carbide is an excellent ceramic material suitable for applications requiring good corrosion resistance and wear resistance.

Silicon carbide is formed in two ways, reaction bonding and sintering. Each forming method greatly affects the end microstructure.

Reaction bonded SiC is made by infiltrating compacts made of mixtures of SiC and carbon with liquid silicon. The silicon reacts with the carbon forming more SiC which bonds the initial SiC particles.

Sintered SiC is produced from pure SiC powder with non-oxide sintering aids. Conventional ceramic forming processes are used and the material is sintered in an inert atmosphere at temperatures up to 2000ºC or higher.

Both forms of silicon carbide (SiC) are highly wear resistant with good mechanical properties, including high temperature strength and thermal shock resistance. Our engineers are always available to best advise you on the strengths and weaknesses of each ceramic for your particular needs.

The crystal structure of the SiC ceramic wear-resistant pipe is similar to that of the diamond tetrahedral structure. It is a compound composed mainly of covalent bonds. Its hardness is high (Mohs 9.3), its performance is stable, and its physical properties are similar to diamond. It is also known as emery. Black silicon carbide crystal Hardness is the second-order material for diamonds. It is mainly used for making abrasives and grinding wheels, and partly for the production of silicon carbide ceramics.

Selection Criteria for Silicon Carbide Nozzle Cleaners

Silicon carbide nozzles are used for desulfurization in power plants to remove sulfur dioxide and some polluting gases in the flue gas of power plants. The flue gas of coal-fired power plants and the gas in the gas turbine coal-fired combined cycle have a common task, which is desulfurization and denitrification (and of course dedusting).

SiC Swirl Nozzle

The flue gas emitted by the power plant without desulfurization and denitrification directly pollutes the atmospheric environment, while the combined cycle flue gas without purification treatment will cause damage to the hot-end components of the gas turbine, and the exhaust gas will also pollute the environment. The reason why silicon carbide nozzles are chosen instead of nozzles of other materials is that it has excellent properties such as high strength, high hardness, strong corrosion resistance, severe wear and high temperature resistance, and has a long service life under harsh conditions. However, after the silicon carbide nozzle works for a long time in a harsh environment, it is also necessary to clean up the dirt, otherwise it will affect the normal spraying. Let us explain how to choose an additive for cleaning silicon carbide nozzles.

  1. First, choose a product that cleans dirt quickly and dissolves it thoroughly. The cleaning agent itself has a strong ability to react, disperse or dissolve the dirt, and can remove the dirt more thoroughly in a limited period of time.
  2. The damage of the cleaned silicon carbide nozzle should be within the scope of production license, and corresponding measures should be taken to inhibit the corrosion that may be caused by the metal.
  3. Chemicals for cleaning are cheap and readily available, and are based on localization; cleaning costs are low and do not cause excessive resource consumption.
  4. The cleaning agent is non-toxic or low-toxic to organisms and the environment, and the generated waste gas, waste liquid and waste residue should be able to meet the requirements of relevant national regulations.
  5. The cleaning conditions are mild, and try not to depend on the strengthening conditions of the attachment port, such as temperature, pressure, mechanical energy, etc., and do not require too high requirements.
  6. The cleaning process will not leave insoluble matter on the surface of the object to be cleaned, will not produce new stains, will not form a new covering layer that is harmful to the subsequent process, and will not affect the quality of the product.
  7. Does not produce foam and odors that interfere with the cleaning process and on-site hygiene.
Silicon Carbide Products

Silicon Carbide Products

What is silicon carbide?

Silicon carbide (SiC) is a lightweight ceramic material with high strength properties comparable to diamond.

Silicon carbide (SiC) is a synthetic crystalline mineral containing silicon and carbon, generally produced in electrical resistance furnaces at high temperatures of 1700 – 2500 °C.

It has excellent thermal conductivity, low thermal expansion and is resisitance form acids. Silicon carbide ceramic is excellent for applications requiring good erosion and abrasive resistance. Consequently, it is useful in a variety of applications including spray nozzles, shot blast nozzles, ceramic tubing and cyclone components.

A mixture of a carbon material and a silica or quartz sand, it is made to react chemically, resulting in the formation of SiC, which develops as a solid cylindrical ingot around the core, with radial layers ranging from graphite in the inside to ­α-SiC (the highest-grade material with coarse crystalline structure), β-SiC, metallurgical grade and finally un-reacted material on the outside, which is remelted. SiC can be produced in either black or green, depending on the raw materials used.

Once it is cooled, the SiC ingot is sorted accurately and mainly manually by skilled workers and further processed for different applications. The solid SiC material is then carefully crushed, classified, and milled again if necessary. Another option is to further chemically treat the SiC to obtain specific properties for its applications.

The many features and applications of silicon carbide in a wide range of industries

Silicon carbide provides benefits for high-temperature, high-voltage and high-power applications.
These include:

  • Great mechanical strength, including high levels of hardness
  • Great high-temperature resistance, combined to low thermal expansion and high thermal consistency
  • Chemical inertness at all temperatures
  • Variable electrical conductivity, including semi-conductor properties and non-linear electrical resistance

Thanks to its versatile properties, silicon carbide is a widely used ceramic material in many high-temperature and wear-resistant applications in many industries, such as:

  • Refractory applications in the production of iron, steel, ceramics, nonferrous metals, energy, chemicals, etc.
  • A high-temperature gas sensor in devices in chemical production and in turbine or engine testing to detect flammable and combustible gases in harsh, high-temperature, and corrosive environments
  • Ceramic welding powders
  • Semiconductors in electronics for circuit elements thanks to its high-voltage resistance

We produce sintered SiC tubes, reaction bonded SiC tubes and recrystallized SiC tubes. Our recrystallized SiC products have a high purity, while our reaction bonded and sintered silicon carbide tubes have a high mechanical strength. Our silicon carbide tubes possess good wearability,a low thermal expansion coefficient, extreme corrosion resistance, wear resistance, thermal shock resistance, high hardness and self-lubricating properties.

Properties

Silicon carbide (SiC) ceramics have a set of unique physical-chemical properties, such as high hardness and mechanical stability at high temperatures, excellent thermal conductivity and low coefficient of thermal expansion, high resistance to corrosion and oxidation, wide bandgap, and others.

  • High hardness (second only to diamond)
  • Low density 40% the density of steel – approximately the same as aluminium
  • Low porosity
  • Good wear resistance in sliding and abrasive environments
  • Excellent corrosion resistance in most chemical environments
  • Low thermal expansion and high thermal conductivity leading to excellent thermal shock resistance.
Properties of Silicon carbide

Silicon carbide tube specifications

 Item Recrystallized SiC Sintered SiC Reaction Bonded SiC
Purity of Silicon Carbide 99.5% 98% > 88%
Max. Working Temp. (`C) 1650 1550 1300
Bulk Density (g/cm3) 2.7 3.1 > 3
Appearance Porosity < 15% 2.5 0.1
Flexural strength (MPa) 110 400 380
Compressive strength (MPa) > 300 2200 2100
Thermal expansion (10^-6/`C) 4.6 (1200℃) 4.0 (< 500℃) 4.4 (< 500℃)
Thermal conductivity (W/m.K) 35~36 110 65
Main characteristics High temp. High resistance.
High purity
Fracture Toughness Chemical Resistance

Properties of reaction bonded silicon carbide

Reaction Bonded SiC has the lowest cost production technique with a course grain. Reaction Bonded SiC provides somewhat lower hardness and use temperature, but higher thermal conductivity. Reaction bonded silicon carbide has high strength, high hardness, hig abrasion resistance, high temperature resistance, corrosion resistance, good oxidation resistance, good thermal shock resistance, good thermal conductivity, rapid cooling and rapid heat resistance and high temperature creep resistance, etc. It can be made into beam, roller, cooling air pipe, thermocouple protection pipe, temperature measuring pipe, burner nozzle, wear-resisting parts, corrosion-resisting parts, sealing parts and a variety special-shaped structural parts.

Properties of pressureless sintered silicon carbide

Properties of Silicon carbide

Compared with reaction bonded silicon carbide, pressureless sintered silicon carbide has higher purity, better mechanical properties, more prominent corrosion resistance ( Resistantto strong acid and alkali corrosion, It is also the only ceramic material which can resistant to hydrofluoric acid corrosion ), higher wear resistance, because of there’s no free silicon in the material can be used in other materials can not meet the environment, longer service life.

Silicon carbide ceramic inner sleeve custom size

Silicon carbide ceramic inner sleeve custom size

Advantages

At present, the use of our company’s high wear-resistant ceramic lined steel pipe dozens of thermal power plant practice shows that: ceramic lined steel pipe anti-wear ability, anti-fluid erosion ability.

  1. High strength: as the outer wall of the composite steel pipe is made of common ordinary steel pipe, the strength requirements of various processes are fully satisfied, under the support of the outer wall steel pipe.
  2. High wear resistance: Most of the inner wall of the steel pipe is a high wear-resistant ceramic which are selected according to the process requirements. The ceramic content is more than 95%. Thus, the product has good wear resistance.
  3. High anti corrosion: As the composite layer is made of corrosion-resistant materials, it seems to solve the main problems. It can be widely used in sites containing acid, alkali and salt.
  4. High bond strength: The matrix of the composite is made of organic polymer. On the basis of inorganic ceramic as a reinforcing agent, it is articulated under the environment of specific temperature, pressure and proper vacuum. At the same time, together with the inner wall of the steel pipe, the peeling strength is up to 14-16 MP which is is more than 100 times of the ordinary lining pipe. However, the difference of thermal expansion coefficient of composite layer leads to the phenomenon of inner liner falling off.
  5. Weather ability: This product can be used for 40 to 200 degrees for a long period of time. It can be as high as 260 degrees. This product is widely used in environmental protection, electric power, chemical industry, metallurgy, mining and other industries. It is an ideal substitute for lining plastic pipes.

And it has developed rapidly. When transporting the materials with the harder abrasion (such as ash dregs, slag, coal powder, mining dregs, the rest mines, cement, etc), it will exit the problem that the abrasion of pipes is too rapid. Especially, the abrasion of bent pipes is greatly more rapid.

When transporting the special abrasion materials or erosive materials, it will exit the problem that the damage of pipes is too rapid.

SiC Ceramic lined pipe and the traditional steel pipe, wear-resistant alloy cast steel pipe, cast stone pipe and steel, steel and other rubber pipe is essentially different. Ceramic lined pipe is the outer layer of steel, the inner layer is RBSiC ceramic. Moh’s hardness of up to 13. Wear resistance than carbon steel pipe more than 30 times higher.

In a duct, the elbow wear the fastest, in practice, Ceramic lined pipe used after 1 to 2 years to open the observation and measurement, the composite layer are no obvious wear or tear off, ceramic-coated steel pipe wear Than the thick-walled wear-resistant cast steel pipe increased by nearly 10 times.

silicon carbide

Parameter comparison

Silicon carbide (SiC) is a lightweight ceramic material with high strength properties comparable to diamond. It has excellent thermal conductivity, low thermal expansion, and is resistant to acid corrosion.

Comparison of parameters of silicon carbide ceramic products of different materials

Comparison of parameters of silicon carbide ceramic products of different materials

Liquid corrosion test data for different materials

Silicon carbide is an excellent ceramic material suitable for applications requiring good corrosion resistance and wear resistance.

Liquid corrosion test data for different materials

Remarks

Properties of Silicon carbide
Silicon carbide (SiC) Application

Applications

Silicon carbide (SiC) ceramics have a set of unique physical-chemical properties, such as high hardness and mechanical stability at high temperatures, excellent thermal conductivity and low coefficient of thermal expansion, high resistance to corrosion and oxidation, wide bandgap, and others.

Armor

Sintered Silicon Carbide has demonstrated an excellent performance record as ceramic material in composite armor protection systems. The properties of sintered silicon carbide, such as its high hardness, compressive strength and elastic modulus, provide superior ballistic capability when confronted with high-velocity projectiles. The low specific density of the material makes it suitable in applications where weight requirements are critical.

Heat Exchanger Tubes

Sintered Silicon Carbide tubes are used in shell and tube heat exchangers in the chemical process industry. The tubes used in these applications are often over 4 m in length.

Mechanical Seals

Pumps must operate in an infinite variety of demanding environments. Sintered Silicon Carbide offers a high performance seal face material that has proven successful in such diverse pumping applications as chemical processing, refining, mining and pulp and paper processing. The material provides superior corrosion and abrasion resistance; shock resistance; and low sliding friction against a wide range of mating materials.

Bearings

For state-of-the-art magnetically driven pumps, sintered silicon carbide is particularly suited for thrust and journal bearing components. Excellent corrosion resistance provides optimum performance in many chemical environments. High thermal conductivity minimizes the likelihood of failure due to thermal shock, and its specific strength makes it safe to use at high rotational speeds. Bearing components are usually produced as tight tolerance precision ground parts.

Automotive Components and Seal Faces

Due to their greater resistance to both wear and thermal shock, sintered silicon carbide seal faces for automotive water pumps are replacing seal faces made of materials such as aluminium oxide. In many cases the material has proven more suitable in meeting the performance demands of U.S. and European vehicles – i.e. lasting the lifetime of the vehicle without leaking. These components are manufactured by conventional high volume pressing and injection moulding methods to meet the economic constraints of the application.

Blast and Atomization Nozzles

Sintered Silicon Carbide is probably the most popular ceramic alternative to tungsten carbide for blast nozzle applications. Typically providing long life (50% over WC) due to excellent wear and corrosion resistance. The low wear rate maintains the internal nozzle geometry and provides maximum blasting effectiveness, minimum compressor requirements and reduced downtime due to replacement. Sintered silicon carbide is also about one fifth the weight of Tungsten Carbide, so the blasting operation is also easier for the operator. Nozzles are often produced as semi finished (non-ground) components thereby reducing costs.

Process Industry Valve Applications

The outstanding corrosion resistance of sintered silicon carbide, particularly in acids, makes it an ideal candidate for valve and valve trim applications. Typical demanding applications such as slurry flashing, HF acid handling and rare earth processing use sintered silicon carbide valve components.

Paper Industry Applications

The excellent corrosion and wear resistance of sintered silicon carbide provides hard surfaces that can be machined to smooth, highly polished finishes. These finishes offer low coefficients of friction and compatibility with forming fabrics. Tiles, inserts and palm guides are available in finished and semi-finished forms.

Centrifuge Tiles and Wear Parts

Often used in applications where tungsten carbide and alumina fail to provide optimum lifetime performance.

Semiconductor Production

The benefit of using silicon carbide for semiconductor components includes; the thermal expansion match to silicon, the resistance to wear and chemical corrosion which leads to reduced maintenance and component recycling. The material is well suited as a structural material for low mass silicon wafer handling components and rigid, dimensionally stable platforms due to its lightness in weight and high elastic modulus. Typical applications include vacuum chucks, chemical mechanical polishing blocks, wafer carriers, and thermocouple protection tubes.

Correct use of silicon carbide ceramics

Silicon carbide ceramics are widely used not only in industry, but also in other fields. So, what should be paid attention to when using silicon carbide ceramics?

The hardness of silicon carbide ceramics is very strong, although it does not look as eye-catching as other ceramics, but the use of ornamental ceramics is incomparable. In the process of use, as long as you follow the instructions, there is no need to pay special attention to. Just keep it clean.

If the method used is not correct, the silicon carbide ceramics will be damaged. We can extend its service life by regular maintenance.

Packaging

Our silicon carbide tube and fitting is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition. We guarantee intact during transportation, loading and unloading, and have measures to reduce vibration and impact, so as to ensure the integrity of the product during transportation.

Our Silicon Carbide Tubes (SiC Tubes) are carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition.

Packaging and delivery of carbide tube
Packaging and delivery of carbide tube Packaging and delivery of carbide tube
Packaging and delivery of carbide tube Packaging and delivery of carbide tube Packaging and delivery of carbide tube
Packaging and delivery of carbide tube Packaging and delivery of carbide tube

Working condition of silicon carbide ceramic wear-resistant pipe

Typical silicon carbide characteristics include:

  • Low density
  • High strength
  • Good high temperature strength (Reaction bonded)
  • Oxidation resistance (Reaction bonded)
  • Excellent thermal shock resistance
  • High hardness and wear resistance
  • Excellent chemical resistance
  • Low thermal expansion and high thermal conductivity

Typical silicon carbide applications include:

They are used more for operation with wear at low temperature than for high temperature behavior. SiC applications are such as sandblasting injectors, automotive water pump seals, bearings, pump components, and extrusion dies that use high hardness, abrasion resistance, and corrosion resistance of carbide of silicon.

  • Fixed and moving turbine components
  • Seals, bearings, pump vanes
  • Ball valve parts
  • Wear plates
  • Kiln furniture
  • Heat exchangers
  • Semiconductor wafer processing equipment

Metallurgy and power industry: The reason why these two industries are put together is mainly because the two industries have a large number of metal pipes for the transmission of coal powder, ash, mud, and the like. After using the wear-resistant elbow pipe, the advantages of strong wear resistance, long life and easy installation are immediately highlighted.

Mining industry: If the wear-resistant elbow pipe is not used, the ordinary pipe is used for the transportation of the ore powder. Due to the filling of the mine and the transportation of the concentrate powder, the wear of the pipe is relatively large, so that the life of these pipes is only about one year. After wearing elbow pipes, the life of such pipes will be extended by a factor of five.

Coal industry: If long-distance wet transport of coal is required, the pipe has the requirements of good wear resistance and high corrosion resistance, and the pipe with wear-resistant elbow can meet these requirements well.

【H】 Ceramic lined pipe

Ceramic lined pipe is made through self-propagating high-temperature synthesis (SHS) technique.

【H】 Cast basalt lined steel pipe

Cast basalt lined steel pipe is composed by lined with cast basalt pipe, outside steel pipe and cement mortar filling between the two layers.

【H】 Ceramic Tile Lined Pipes

Ceramic tile lined pipes have very uniform coating of specially formulated ceramic material that is affixed to the inner of the pipe.

【H】 Rare earth alloy wear-resistant pipe

The material of the rare earth alloy wear-resistant pipe is ZG40CrMnMoNiSiRe, which is also the grade of rare earth alloy steel.

【H】 Tubes Erosion Shields

Tubes Erosion Shields are used to protect boiler tubing from the highly erosive effects of high temperatures and pressures thereby greatly extending tube life.

【H】 ASTM A213 T91 Alloy Tube

The ASTM A213 T91 seamless tubes are primarily used for boiler, superheater, and heat-exchanger.

Ni-Hard Wearback Pipes Ni-Hard Wearback Pipes