silicon carbide thermocouple protection tube

Types of Silicon Carbide Thermocouple Protection Tubes

Thermocouple protection tubes are an essential element in any industrial kiln using metals such as aluminum, zinc and copper. They shield thermocouple terminals from harsh environments, thermal shocks and direct flame impingements.

German physicist Thomas Seebeck discovered that when two dissimilar metals with different temperatures came into contact, an electric current flowed between them – this phenomenon is known as the Seebeck effect.


Oxide-bonded silicon carbide thermocouple protection tubes are an excellent choice for applications involving molten metal, offering exceptional corrosion resistance, flexing strength and high thermal conductivity. Furthermore, their excellent corrosion resistance, flexing strength and thermal conductivity make them perfect for industrial kilns used to produce ceramics, metal or large boiler applications as they resist extreme heat without expansion and chemicals without expansion – perfect for large boiler applications or ceramic manufacturing facilities. They come available as reaction bonded versions (nitride-bonded), carbon (isopressed). Finally for added flexibility they come as reaction bonded (nitride bonded) varieties for greater versatility of use.

Oxide-bonded silicon carbide protection tubes are the most frequently utilized kind, fabricated using black alpha/beta silicon carbide powder mixed with SiO2. After sintered at high temperatures to ensure no air pockets remain within the material, oxide-bonded tubes can provide maximum wear resistance even in environments with high levels of abrasion or wear.

Hexoloy SE is a single phase, low porosity refractory ceramic made with Hexoloy alpha silicon carbide that offers one of the strongest and most reliable protection tubes available today. Ideal for environments exposed to chemically reactive environments containing acids, bases or oxidizers; Hexoloy SE features excellent flexing strength at elevated temperatures as well as superior corrosion and abrasion resistance as well as outstanding thermal shock resistance; plus stronger and more flexible performance than commercially available ceramics or metal alloys while withstanding higher pressures than conventional materials can.


Nitride-bonded silicon carbide exhibits superior mechanical strength and is capable of withstanding creep, oxidation, corrosion and thermal shock. Furthermore, this material boasts superior fracture toughness with low coefficient of expansion at high temperatures; making it the ideal material for kiln furniture due to its non-wetting characteristics against aluminum melts and other metal alloys.

Hexoloy SE sintered silicon carbide is made through pressure-less sintering of submicron powder in a special extrusion process, producing a fine-grained, dense (85%) product with exceptional resistance to corrosion, oxidation and high temperatures. Highly durable and inert with most acids or alkalis; available in various outer diameters and lengths to fit different temperature sensor types.

The thermocouple is a device for measuring temperature by monitoring differences in electrical potential between dissimilar metals joined at their ends, such as furnaces or metal casting machines. A thermocouple can be found in many applications to measure temperatures such as furnaces or metal casting shops.

Hexoloy SE tubes feature one closed end with a standard threaded connection for fittings or mounting flanges, as well as excellent thermal conductivity and fast response time to changes in temperature – making it an excellent choice for measuring liquid and gas temperatures in process applications. Furthermore, its extremely resistant surface and inert material properties eliminate iron pick-up risks associated with cast iron tubes.

Hexoloy SE Sintered

Hexoloy SE is an advanced sintered alpha silicon carbide material designed for superior performance in harsh and corrosive environments. With high purity results in superior hardness and strength as well as low porosity compared to traditional ceramics or metal alloys. Hexoloy SE features self-lubricating surface features with spherical pores to lubricate moving parts or mechanical seal faces, helping reduce wear in friction applications while offering exceptional resistance against corrosion, high temperatures and good thermal conductivity properties.

Hexoloy is produced through a pressure-less sintering process that converts powdered material directly into solid material without melting it first, replicating what happens naturally under intense heat and pressure in Earth’s crust over millennia – crystal formation under high heat pressure, etc.

The result is a material as hard as diamond, yet 2.5 times lighter, resistant to abrasion and corrosion and capable of withstanding temperatures up to 1,950 degC when placed under inert gas conditions such as air or nitrogen. Furthermore, its coefficient of thermal expansion is extremely low allowing it to withstand temperature shock better than tungsten carbide, aluminum oxide or Reaction Bonded silicon nitride materials.

Saint-Gobain Ceramic Materials engineers spent decades perfecting Hexoloy into an excellent ceramic material that can outperform conventional ceramics and metals under armor, high temperature, chemical and abrasive conditions. Working closely with customers, Saint-Gobain engineers specialize in developing engineered solutions tailored specifically for each application – offering tailored engineered solutions tailored specifically to customer applications and meeting all their specific requirements.

Reaction Bonded

Reaction bonded silicon carbide (RBSC) is an advanced technical ceramic made by pressureless sintering of submicron-sized silica particles, featuring excellent dimensional stability and temperature resistance, as well as outstanding chemical resistance for both oxidizing and reducing conditions, including acid corrosion resistance. Furthermore, this material’s thermal conductivity enables fast heat transfer even at elevated temperatures in harsh environments, with wide bandgap properties that make it highly durable.

Reactive-bonded silicon carbide offers the lowest production costs and is course-grained, providing superior wear resistance and corrosion resistance with strength 1.5 times that of tungsten carbide. Its superior wear resistance makes it suitable for temperature measuring equipments used in industrial kilns for ceramic, metallurgy and large boiler applications while its fast cooling time and rapid heat impingement capabilities allow rapid heat impingement processes to take place quickly.

Attractant for mechanical seals, flow control chokes, pipe liners and larger wear parts used in mining industries is made of hard, tough material with great abrasion-resistance that is light in weight with density half that of steel; its hardness and tensile strength rival both titanium and tungsten carbide materials. It has excellent thermal shock and wear resistance properties. As it resists chemical corrosion as well as thermal shock shock and wear resistance – ideal qualities when used in components with complex shapes. Titanium carbide also compares well against both titanium and tungsten carbide materials in terms of wear resistance compared to their respective counterparts – ideal for mechanical seals, flow control chokes, pipe liners and larger wear parts used across industries. Titanium carbide has superb chemical corrosion resistance properties as it has excellent chemical corrosion resistance as thermal shock and wear resistance properties similar to titanium and tungsten carbide materials while having comparable hardness/tensile strength ratings comparable to titanium/tungsten carbide materials with regard to thermal shock/wear resistance properties as well as light density comparable to steel while possessing comparable hardness/tensile strength properties comparable to both titanium/tungsten carbide materials when exposed.

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