SSIC Thermocouple Protection Tube

SSIC Thermocouple Protection Tube

The pressureless sintered silicon carbide thermocouple protection tube has the characteristics of oxidation resistance, high thermal conductivity, corrosion resistance, thermal shock resistance and excellent high temperature strength, etc.

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It can withstand high temperature and the erosion of strong corrosive substances, which is the best material for making thermocouple protection tube. Silicon carbide thermocouple protection tube is usually used with the thermocouple, thermostat, thermometer, etc., mainly for protecting the sensor from being damaged by external forces, preventing the internal components from being corroded by harmful substances in the environment, and quickly and accurately transferring heat energy. Silicon carbide has a strong ability in heat resistance, oxidation resistance, heat shock resistance, wear-resistance and chemical stability, etc. It is an ideal material for a high-performance thermocouple protection tube.

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.

heat SSIC tube

heat SSIC tube

What is SSIC tubes?

SSIC (Sintered Silicon Carbide) tubes are high-performance ceramic components renowned for their superior mechanical and thermal properties.

These tubes are extensively used in various industrial applications due to their exceptional hardness, thermal stability, and resistance to wear, corrosion, and thermal shock.

Indirect gas heating is an important method in the sintering, melting, heat treatment of metallic materials and glass industries. Compared with direct combustion heating, indirect gas heating can greatly improve the thermal efficiency and reduce the emission of NO and other harmful gases. At the same time, the temperature stability is improved to ensure the control of the atmosphere in the furnace. At the same time, many industrial heating processes require isolation of the workpiece and combustion environment. All of this must be heated by indirect radiation. Traditional indirect heating mainly uses metal or its alloy as the radiant tube of the heating system, but up to now, the upper limit of the maximum operating temperature of various metal radiant tubes is only 1000℃, which cannot meet the higher heating temperature required by many processes. At present, the main problem is the reliability problem of long-term use in higher temperature and more complex media.The pressureless sintered SiC radiant tube can be used stably for a long time in various corrosive media at a high temperature of 1650℃.

SSIC tubes are manufactured through a process of sintering silicon carbide powder with a siliconizing agent, resulting in a dense, hard material with a fine-grained structure.

Replied by clients:

Hi SumXu,
all the tubes were delivered unbroken so thanks for safe packing. Dimension are fine, so we will try heat them soon. Have a nice day.
BR David

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
SSIC tubes

Packing

SSIC tubes

Measure length

SSIC tubes

Out diameter

SSIC tubes

Wall thickness

SSIC tubes

Inside packing

SSIC tubes

Out diameter

SSIC tubes

Inside diameter

SSIC tubes

Inside diameter

SSIC tubes

Packing

SSIC tubes

Packing

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

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.