Advantages and Disadvantages of Silicon Carbide Refractory Castables

Rongsheng Refractory Manufacturer, solutions for high temperature industrial furnace lining refractory materials. Advantages and disadvantages of silicon carbide refractory castables. In the field of amorphous refractory materials, silicon carbide refractory castables have always been a product that has attracted much attention. Whether from raw materials to research and development, or from production to use, it is a product that users love and hate. Understanding the advantages, disadvantages and why silicon carbide refractory castables can resist slag erosion can help companies make better choices.

Advantages and disadvantages of silicon carbide refractory castable products

The biggest advantage of silicon carbide refractory castable is that it has high thermal conductivity, low thermal expansion, and does not react with slag. It has been used in kiln parts with severe slag reaction and high-temperature spalling since a long time ago.

Rongsheng Silicon Carbide Refractory Castables

The biggest disadvantage is that the chemical properties are very unstable in certain atmospheres. It is easily corroded in oxidizing gases such as (oxygen, water vapor, carbon monoxide, carbon dioxide), iron oxide, etc., and easily oxidized and decomposed in molten iron and vacuum. Another disadvantage is that silicon carbide refractory castables have poor water solubility. In water-based amorphous refractory materials such as castables, the poor fluidity sometimes causes the poor density of silicon carbide refractory castables. The third disadvantage is the lack of sintering and difficulty in obtaining high strength, but sometimes it is difficult to produce over-sintering and shrinkage, which is a strength in amorphous refractory materials.

Why is silicon carbide refractory castable resistant to slag erosion?

When considering the slag resistance and slag resistance of silicon carbide refractory castable, the following aspects must be considered comprehensively: (1) wettability to slag (contact angle) (2) slag invasion (3) reactivity with slag (4) melting point and viscosity of reaction products. Considering these four aspects, although alumina refractory materials are materials that easily react with slag, as raw materials of refractory materials, they are not materials with poor slag resistance. This is because there are not many low-melting point compounds generated by reaction with slag.

The reason why silicon carbide refractory castable is difficult to be wetted by slag is because of the material of silicon carbide itself. SiC has two crystal forms, α and β, and the crystal structure of β-SiC. Among them, α-SiC has about 120 polymorphs such as 4H, 15R and 6H, among which 6H polymorph is the most widely used in industry. In 6H-SiC, Si and C are stacked alternately in layers, the distance between Si layers or C layers is 2.5Å, and the atomic distance between Si-C is about 1.9Å. There is a certain thermal stability relationship between the various forms of SiC, and the α β crystal forms also transform into each other. When the temperature is below 1600℃, SiC exists in the form of β-SiC. When the temperature is higher than 1600℃, β-SiC slowly transforms into various deformation forms of α-SiC (4H, 15R, 6H, etc.) by recrystallization. For α-β transformation, higher pressure is required, while for β-α transformation, only lower pressure is required. The transformation between various types of silicon carbide does not produce volume effect. SiC is a compound with strong covalent bonds. It still maintains high bonding strength at high temperatures, so SiC has high hardness, large elastic modulus, excellent wear resistance, and will not be corroded by most acid and alkali solutions. For the intrusion of slag and the melting point generated after reaction with slag, when compared with oxides, the slag resistance is significantly better.

When using silicon carbide refractory castables in monolithic refractory materials, the advantages, disadvantages, and prices of use should be considered. Only after the use site is determined can the lining material be used more accurately. However, in the actual use environment of monolithic refractory castables, these favorable and unfavorable environments for silicon carbide are mostly mixed. The evaluation of many environments currently used is often inconsistent with the actual use environment.

Lightweight High-Strength Thermal Insulation Castable

Lightweight high-strength castable is a new type of refractory material newly developed by Rongsheng Refractory Material Manufacturer. Rongsheng Lightweight High-Strength Thermal Insulation Castable combines the advantages of lightweight materials and high-strength characteristics and is widely used in high-temperature industrial equipment. This material not only has good thermal insulation performance but also is comparable to heavy refractory bricks in strength. Contact Rongsheng for more information.

Lightweight High-Strength Insulation Castable

Basic Characteristics of Lightweight High-Strength Castables

Lightweight high-strength castables are composed of refractory aggregates (such as lightweight particles), binders, and additives (such as reinforcing materials). Its main characteristics include:

• Lightweight: The castable contains lightweight aggregates (such as lightweight bauxite, expanded perlite, lightweight silicates, etc.), which makes the overall weight of the material lighter and has a lower density.
• High strength: Although it is a lightweight material, after special formula design and process treatment, it can achieve strength similar to that of traditional heavy refractory bricks, and can withstand large mechanical loads and structural stresses at high temperatures.
• Thermal insulation: Due to the special structure of its lightweight aggregate, lightweight high-strength castables have excellent thermal insulation properties, which help to reduce heat loss and improve energy efficiency.
• High refractoriness: This type of castable is usually composed of refractory aggregates and binders, has high refractoriness, and can work stably in high-temperature environments.
• Thermal shock resistance: Due to its certain elasticity and toughness, lightweight and high-strength castables have good thermal shock resistance and can cope with working environments with large temperature changes.

Advantages of Lightweight High-Strength Castables

(1) Thermal insulation performance

Reduced heat loss: The lightweight aggregate of lightweight high-strength castables makes it have lower thermal conductivity, which can effectively reduce the conduction and loss of heat. This is of great significance for equipment that needs to maintain high temperatures for a long time (such as blast furnaces, hot blast furnaces, smelting furnaces, etc.), and can reduce energy consumption.

Lightweight High-Strength Castables

Improved temperature control: Good thermal insulation effect makes the temperature distribution in the equipment more uniform, avoids excessive temperature fluctuations, and reduces the occurrence of thermal shock.

(2) High strength

Withstand greater mechanical stress: The high-strength design enables lightweight high-strength castables to withstand greater mechanical stress and impact, especially in some areas affected by high temperature and pressure (such as the inner wall of the furnace, the bottom of the furnace, etc.), and can maintain stability.

Comparable to heavy refractory bricks: Traditional heavy refractory bricks have higher strength, but are often heavier and are not suitable for occasions where a lower dead weight is required. The strength of lightweight high-strength castables has been optimized to be comparable to that of heavy refractory bricks, while having a lower density.

(3) Convenient construction

Quick forming: Castables are constructed by pouring, vibrating or spraying, which is particularly suitable for irregular shapes and difficult-to-brick parts. This construction method not only saves time and manpower, but also avoids the existence of bricklaying joints during the construction process, improving the construction quality.

Adaptable to complex structures: Since the material is in a cast state, it is suitable for use in furnace bodies, furnace walls, furnace bottoms and other parts with complex shapes or difficult to cut and splice.

(4) Good thermal shock resistance

Lightweight and high-strength castables can better adapt to working environments with large temperature fluctuations due to the structural characteristics of their lightweight aggregates, avoiding thermal stress and cracks caused by drastic temperature changes. This enables it to effectively improve durability and stability in equipment such as hot blast furnaces and blast furnaces.

(5) Energy saving and maintenance reduction

Due to its excellent thermal insulation performance, lightweight high-strength castables help improve the energy efficiency of the equipment. It reduces energy waste and enables equipment to operate at a higher thermal efficiency, reducing operating costs.

Its good thermal shock resistance, high-temperature resistance, and strength also extend the service life of the refractory lining, thereby reducing the frequency of maintenance and replacement and reducing overall operating costs.

Rongsheng Refractory Castable Manufacturer

Rongsheng's lightweight high-strength castable is a refractory material that combines light weight, high strength, excellent thermal insulation and thermal shock resistance. It can provide good performance in high-temperature metallurgical equipment. Compared with traditional refractory bricks, it can provide similar or even stronger strength. And due to its lightweight structure, it has better thermal isolation effect, helping to improve the energy efficiency of equipment and reduce repair and maintenance costs. It is especially suitable for metallurgical equipment that requires high strength, good thermal insulation and high temperature resistance and thermal shock resistance. Such as blast furnaces, hot blast furnaces, coke ovens, steelmaking furnaces, etc.

Quality Requirements for Checker Bricks in Coke Oven Regenerators

The quality requirements of the checker bricks in the heat storage chamber are mainly as follows:

1. In order to reduce the friction resistance of the gas flowing in the checker bricks and make the resistance in each heat storage chamber consistent, it is convenient to master the heating system, and the holes of the upper and lower layers of the checker bricks are required to be aligned as much as possible.

2. Keep the checker bricks clean to avoid blockage of the brick holes and reduce the number of cleaning times during production to improve heating efficiency.

3. The bricklayer should be laid smoothly and have a good staggered width.

4. Maintain necessary expansion joints. The gas flow space at the top of the heat storage chamber should maintain a certain cross-sectional area according to the design to prevent vortexes from being generated when the gas is distributed at the top of the heat storage chamber.

Rongsheng Checker Bricks

Rongsheng Refractory Manufacturer, Regenerator Checker Brick, Magnesia Checker Brick. Contact Rongsheng for more information.

Construction of checker bricks

The laying time of checker bricks is divided into two construction methods according to the width of the regenerator: laying at the same time as the regenerator furnace wall (first laying) and laying after the entire furnace body is built and cleaned (latter laying). According to construction experience, when the net width of the regenerator is less than 310 mm (such as Otto coke oven), the construction method of laying checker bricks first should generally be adopted. This is because it is more difficult to lay checker bricks later in a narrow regenerator.

The construction method of laying checker bricks first has several advantages: First, because the workers are standing on the wall of the regenerator to lay checker bricks, the operating conditions are better, and it is easy to check after laying. Therefore, it can ensure that each checker brick hole is connected from top to bottom and has good staggered joints. However, due to the addition of many processes - cleaning protection and cleaning work, the construction progress is slow and it is more difficult to ensure cleaning.

The construction method of laying checker bricks is as follows: checker bricks can be laid in sections, that is, according to the convenience of construction, they can be laid in two sections on the entire height of the heat storage chamber, that is, divided into upper and lower sections according to the height of the replacement handrail. After the first section of the main wall is built, all the cleaning and brick joint finishing work on the wall surface is completed, and the grate bricks are cleaned, and the row numbers of the grate bricks are checked once, and then the first layer of checker bricks is placed on the grate foot platform according to the designed position, and the expansion joints on the four sides and the staggered joint width between the checker bricks and the grate foot platform are checked. Make sure that the checker bricks can be firmly placed on the grate foot platform, and finally lay each layer of checker bricks from the center partition wall to both sides according to the designed position.

During construction, the checker bricks are placed on the brick pad. The hook of the checker brick is inserted into the hole of the checker brick to place the checker brick in the heat storage chamber. Then use a long wooden stick to adjust its position. When storing, it can be laid from the center to the furnace head in a stepped shape, or it can be laid layer by layer. The heat storage chamber sealing wall is built after the checker bricks of this section are laid.

After the first section of checker bricks is laid, the checker bricks are covered with a checker brick protection board to prevent waste such as mortar from falling into the checker bricks. Then continue to build the heat storage chamber wall. When it reaches the top of the heat storage chamber, lay the second section of checker bricks and build the second section of sealing wall.

Lime Kiln Refractory Bricks - Refractory Materials for Kilns

Limekiln refractory brick is a kind of refractory material used in a lime kiln, usually made of high alumina, clay, or corundum. Because lime kiln has the characteristics of high temperature and strong corrosion, the performance requirements of refractory materials are relatively high, and lime kiln refractory brick is designed to meet these requirements.

Lime Kiln Refractory Brick Lining

Characteristics of lime kiln refractory bricks

1. High temperature performance. Limekiln refractory bricks can withstand high temperatures, have high thermal stability, and can be used in environments up to 1300°C or above.

2. Corrosion resistance. Since the gases and materials in the lime kiln are corrosive, lime kiln refractory bricks need to have good corrosion resistance.

3. Good thermal insulation performance. Lime kiln refractory bricks can insulate, reduce heat transfer, and improve energy utilization.

4. Wear resistance. In harsh environments such as high temperatures and corrosion, lime kiln refractory bricks need to have good wear resistance to ensure their service life.

Application of lime kiln refractory bricks

Lime kiln refractory bricks are widely used in various types of lime kilns, including vertical kilns, rotary kilns, etc. During use, it is necessary to select appropriate refractory brick models and specifications according to different furnace types and use environments. At the same time, the following points should be noted during use:

• 1. During installation, it should be carried out according to the drawings provided by the manufacturer to ensure the installation quality and service life.
• 2. Avoid collision and extrusion during use to avoid damage.
• 3. Regularly inspect and maintain, discover and solve problems in time, and ensure the normal operation of the lime kiln.

Rongsheng Refractory Brick Manufacturer

Lime kiln refractory bricks are an indispensable part of the lime kiln furnace. Their performance and service life are directly related to the normal operation and production efficiency of the lime kiln. With the continuous development and progress of technology, lime kiln refractory bricks will continue to innovate and develop, providing better support and guarantee for the development of the lime industry.

When choosing suitable lime kiln rotary kiln refractory bricks, we need to analyze the characteristics of different types of refractory bricks in detail. According to the production process and the actual situation of the lime kiln rotary kiln, Rongsheng refractory brick manufacturer can customize refractory lining bricks. For example, for high temperature and high pressure environments, we can choose high alumina refractory bricks or magnesium-alumina refractory bricks. For occasions that require corrosion resistance, we can choose silicate refractory bricks. In the selection process, we need to consider a variety of factors, such as refractoriness, stability, durability, and cost. Contact Rongsheng for free solutions and quotes.

Magnesia Spinel Refractory Brick Manufacturer

In the vast land of China, there is a powerful manufacturer and seller of refractory materials, Rongsheng Refractory Material Factory. Rongsheng Factory has its own unique concept, high-quality products and comprehensive customer service in the field of refractory materials. Magnesia refractory brick, magnesium spinel refractory brick manufacturer. Contact us for free samples and quotes.

RS Magnesia Spinel Refractory Brick Manufacturer

Magnesia Alumina Spinel Brick

Magnesium-aluminum spinel has a series of excellent properties such as high melting point, good thermal shock stability, and resistance to slag erosion. It has been widely used in refractory materials and other industrial fields.

At present, the most common method for preparing magnesium-aluminum spinel is solid-phase reaction synthesis. That is, oxides, chloride oxides or carbonates are used as raw materials, and the raw materials are mixed and pressed into billets and then reacted at high temperature (greater than 1400°C) to prepare spinel. The electric melting method is another commonly used method for synthesizing spinel in industry, which also has disadvantages such as high energy consumption. Although wet chemical methods such as sol-gel method and hydrothermal method can synthesize spinel at a lower temperature, their operation process is complicated, the equipment required is expensive, and the cost is too high to meet the needs of large-scale industrial production.

Magnesium-aluminum spinel bricks produced with magnesia sand and magnesium-aluminum spinel sand as raw materials are usually called magnesium-aluminum (periclite-spinel bricks). The magnesia sand raw material used to produce periclase spinel bricks is required to have as low an impurity content as possible (especially CaO).

Domestic sintered magnesia MS95, MS97, MS97.5, and DMS97 are widely used. Spinel sand is used as granular material, and magnesia sand is used as fine powder and part of the granular material. According to the mixing, forming, and firing process of high-grade magnesia-alumina bricks, products with good high-temperature performance and high thermal shock stability can be produced.

Magnesia-alumina spinel bricks are often used in cement rotary kilns, glass kiln lattices, mixed iron furnaces, and refractory kilns with large temperature changes.

Magnesium Aluminum Chrome Spinel Brick

The magnesium aluminum chrome spinel brick system is the periclase/magnesium aluminum chrome spinel system: MgO-R2O3 (Cr2O3, Al2O3) system. In order to facilitate the comparison of the production of magnesium aluminum chrome products, Cr2O3 is introduced into MgO in the form of chromite, and the manufacturing process often accompanies the appearance of sesquioxides such as Cr2O3, Al2O3, and Fe2O3.

First of all, from the perspective of high temperature resistance and slag resistance, the MgO-MgO·Cr2O3 system has advantages in the MgO-R2O3 system. In addition to its high eutectic temperature (2350℃), it also lies in the low solubility of Cr2O3 in the silicate liquid phase.

As we all know, lower solubility should have stronger crystallization ability. It can effectively reduce the intercrystalline interface energy, so that the silicate liquid phase tends to move into the intergranular gap in an isolated state. It is easy to achieve direct bonding between periclase grains or through magnesium chrome spinel bridges, which can effectively improve high temperature strength and inhibit slag penetration, and improve slag resistance. However, Cr2O3 is highly volatile and has poor stability at high temperatures, especially under vacuum conditions.

Secondly, from the perspective of thermal shock resistance, the MgO-MgO·Al2O3 system is more superior. Because the solid solution-peptization effect of MgO·Al2O3 or Al2O3 in MgO at high temperature is much weaker than that of MgO·Cr2O3 or Cr2O3, especially MgO·Fe2O3 or Fe2O3, and the high-temperature vapor pressure of MgO·Al2O3 above 1600℃ is also lower than that of MgO·Cr2O3. Therefore, the MgO-MgO·Al2O3 system material is more stable when the temperature fluctuates and has good thermal shock resistance.

When the MgO/R2O3 ratio is constant, the MgO-MgO·Al2O3 and MgO-MgO·Cr2O3 systems are compared. It can be inferred that in the molten MgO-MgO·Al2O3 system material, there are fewer precipitated spinels in the periclase grains, and more spinels between the grains. MgO-MgO·Cr2O3 system materials have more intracrystalline precipitated spinel and less intercrystalline spinel. Obviously, changing the proportion of each component in R2O3 can adjust the distribution of spinel phase and change the microstructure.

Magnesium Iron Aluminum Spinel Brick

Magnesia-alumina spinel bricks are mainly used in cement kiln firing zones. Traditional refractory materials used in cement kiln firing zones are mainly magnesia-chrome refractory materials. The highly toxic hexavalent chromium that can be dissolved in water in magnesia-chrome bricks after use will cause serious environmental pollution. Finding chromium-free alternative products for cement kilns has been recognized by experts. Magnesia-alumina spinel bricks were proposed by RHI in the 1990s. It is a mixture of magnesia sand and pre-synthesized alumina spinel, and fired at high temperature under certain processes. It has now been widely used in the lining of cement rotary kilns to replace magnesia-chrome bricks.

The microstructural characteristics of magnesia-alumina spinel are relatively complex, mainly a combination of magnesia sand microstructure and alumina spinel microstructure. The interface between magnesia sand and alumina spinel is closely combined through the mutual diffusion of Mg2+, Al3+, and Fe2+ ions, realizing direct bonding of materials.

Please contact us to purchase high-quality refractory products. Refractory lining materials, refractory services, and furnace lining materials for sale.

Unshaped Refractory Lining Materials for Cupola Linings

Different from the traditional cupola ladle lining, the two types of ladles built with refractory ramming material or refractory castable material can greatly increase the working life of the ladle lining and reduce the number of spare ladles. What are the specific material choices for the two new types of ladle linings?

High-Alumina Refractory Ramming Materials

Refractory Ramming Material Lining

Ramming material is a general term for plastic refractory materials composed of refractory aggregate, binder, and moisture. The mineral composition of refractory aggregate coated with ramming material is generally bauxite, corundum, quartz sand, and quartz powder. The chemical composition is mainly composed of alumina (Al2O3) and silicon oxide (SiO2) two parts. Due to the different mineral compositions and particle sizes, various suppliers have developed a variety of packaging ramming material specifications. At present, the chemical composition of the lining ramming material, among which the higher the alumina content, the higher the use temperature, the greater the drying density, the stronger the thermal conductivity of the lining, and the longer the life of the lining.

Bauxite, corundum, quartz sand, and quartz powder in the lining ramming material are materials with high thermal conductivity. In addition, due to the size grading of refractory materials, the compaction density of ramming materials is larger. Therefore, the thermal conductivity of the lining ramming material is higher. If the ramming material is used completely to build the lining, the heat conduction of the lining causes the temperature of the iron liquid to drop more. Therefore, before using the lining ramming material to build the lining, a heat insulation layer of a certain thickness should be designed inside the cladding.

The ramming die must be prepared in advance to build the packing lining with ramming material. The ramming die is specially designed according to the ladle structure and lining to be located, and either has a certain inclination or has the performance of split disassembly. When building the lining, first use the ramming material layer by layer, ramming the bottom to a certain thickness. Then, the ramming mold is placed in the shell, and the ramming material is filled layer by layer to the mouth of the bag. Finally, pull out or remove the ramming die, and brush the surface of the lining with graphite powder coating.

The construction quality of ramming material lining has a decisive influence on the life of the lining, and the difference in construction quality may make the same material have different life. When building the lining with ramming material, it should be rammed tightly. The ramming compactness must conform to the drying compactness range of the lining material. The drying and roasting temperature and time of the packaging should also meet the technical requirements of the relevant products.

SiC Refractory Castable Lining

Refractory Castable Lining

Refractory castable is a class of amorphous refractory materials with cement as binder. The mineral composition of the refractory aggregate is the same as that of the refractory aggregate used for lining ramming. Calcium oxide (CaO) is an essential component of cement as the binder lining cement castable is high alumina cement. Therefore, the calcium oxide content can indirectly represent the cement content in the castable. Cement-lined castable can be divided into general cement castable, low cement castable and ultra-low cement castable. The lower the cement content, the higher the refractoriness of the material. Chemical composition range of coated low cement and ultra low cement castables. Among them, the higher the Al2O3 and the lower the CaO, the higher the refractoriness and the longer the life of the lining.

Before building the lining with refractory castable, it is necessary to make the casting mold with thin steel plate in advance, and the casting mold needs a certain taper to facilitate smooth pulling out after pouring. A certain thickness of heat insulation layer is set in the interior of the cladding to improve the heat preservation property of the ladle before constructing the cladding with cement castable. During construction, the bottom is covered with castable to the required thickness. After vibrating with a vibrator commonly used in concrete construction, the casting mold is fixed in the cladding. The castable is then filled layer by layer between the insulation layer and the casting mold. At the same time, vibrator is used to vibrate to the envelope, and the casting mold is pulled out in time after the initial solidification of the castable. Finally, the coating surface is coated with graphite powder.

Using low cement or ultra-low cement castable to build the lining is short in construction time, less in physical exertion, and easy to ensure the construction quality. At the same time, the lining can be repaired after partial damage. Therefore, the lining life is long and the consumption of tons of liquid iron refractory is low.

Unshaped Refractory Lining Materials for Cupola

Selection of Amorphous Refractory Castable for Cupola Lining

Cupola is subjected to high temperature and chemical erosion during melting. The melting time of cupola is 6~10 hours, the furnace lining erosion is large, and the furnace condition is unstable.

The corrosive atmosphere of furnace lining has a high requirement on the selection of refractory castable. It is better to use refractory castable with 70%~80% aluminum content in the feeding area and flow channel. Because of the high aluminum content, the high temperature strength and wear resistance and thermal shock performance are good, and the resistance to alternating hot and cold shock is strong.

The main parts of the cupola are hearth, bridge and slag separator. These parts have slag contact, chemical erosion is serious. Refractory castables with high aluminum content, due to the purity of the substrate itself, less impurities, strong resistance to iron wash, and very good oxidation resistance.

When selecting castable material for cupola lining, the slag composition should be considered, because there is a certain proportion of limestone in the burned material. Limestone has an alkaline composition, so the refractory castable used should have the ability to resist alkali erosion. That is, there should be a silicon carbide component in the castable, silicon carbide wear resistance and slag erosion resistance.

If it is alkaline erosion, magnesium or spinel are good choices. If spinel and silicon carbide are added to the castable, then this composite material is the most ideal material. However, silicon carbide and spinel should be added in different proportions according to the different slag composition.

If the top of the furnace lining can also be selected plastic, so easy to construction. Plastic should also consider the composition of ceramic combination, it is best to use phosphoric acid combination of plastic, do not use water glass combination. Because phosphate bonded plastic, strength and high temperature resistance are good. If castable is selected, plastic is still used for daily repair, which can shorten the maintenance time.

It should also be noted that in the furnace production process if the coke does this cupola melting heat source. It is necessary to control the quality of coke to stabilize the use of furnace lining.

In the final analysis, the refractory castable selected for the lining is still a refractory castable with high aluminum content. Because the pure castable has good wear resistance, the castable with silicon carbide or spinel composition has better corrosion resistance.

Are There Any Lightweight Spraying Refractory Coatings?

During the construction process of refractory spray paint material, the material is compacted by repeated and continuous impact of the sprayed material. Therefore, the sprayed coating has a better density and mechanical strength. Refractory spray paint can be used in hot blast duct systems, blast furnace throats, furnace tops and gas outlet pipe systems, furnace bottom foundations, and blast furnace and hot blast furnace linings.

RS Spraying Refractory Coatings for Sale

What is Refractory Coating?

The construction of spray refractory coating actually combines transportation, pouring, or tamping into one process. It does not require or only requires a single-sided formwork. The process is simple, highly efficient, and has good adaptability. During the construction process of refractory spray coating, the repeated and continuous impact of cement, aggregate, and other constituent materials causes the sprayed materials to be compacted, so the spray coating has better density and mechanical strength.

Are There Any Lightweight Spraying Refractory Coatings?

High-temperature refractory coatings and spray coatings are unshaped materials among refractory materials. Therefore, there are also light, heavy, and semi-heavy ones.

Heavy refractory spray paint is relative to light refractory spray paint. Light spray paint refers to a density of 0.5-1.3g/cm3, and medium-heavy spray paint refers to a density of 1.3-1.8g/cm3. Then the density of heavy spray paint is the largest, and its volume density is greater than 1.8g/cm3. Lightweight spray coatings are used as thermal insulation and thermal insulation linings, while medium and heavy spray coatings can be used as both thermal insulation linings and working linings for low and medium-temperature atmosphere furnaces. Heavy spray coatings are mainly used as high-temperature service linings.

Lightweight Spraying Refractory Coating

Applications of High-Temperature Refractory Coating Products

Refractory spray paint is mainly used as a sealing material for the lining of thermal equipment in industrial furnaces. It can be used in hot blast duct systems, blast furnace throats, furnace tops and gas outlet pipe systems, furnace bottom foundations, and blast furnace and hot blast furnace linings.

The lightweight spray coating plays the role of thermal insulation, while the semi-heavy spray coating not only plays the role of thermal insulation, but also can be used as a working layer in furnace linings, chimneys, and pipes where the temperature does not exceed 1000°C.

Heavy refractory spray coatings are generally used for lining hot blast furnaces and blast furnaces and are also used for emergency repairs in lime kiln linings. At present, some domestic manufacturers also spray directly on the lining of the white ash shaft kiln as the working layer. The advantage of refractory spray paint is that it can be applied quickly.

Semi-heavy spray paint is used for flue and chimney linings because the temperature of the flue and chimney linings is not high and there cannot be adequate lining materials. Therefore, many manufacturers choose semi-heavy spray coatings for both thermal insulation and working layers. In this way, the inner diameter space is saved, and it can also prevent wind and smoke erosion.

The lightweight spray paint is used as a thermal insulation layer, and when used, if the area to be used is small, it can also be applied directly. Because the construction time of lightweight spray paint is short, in general, it is convenient and quick to use lightweight spray paint when the usage is large. Because hundreds of tons of spray paint will be sprayed within a few hours.

However, spray coatings have a rebound rate, and the national standard is 20%. However, the rebound rate of spray coatings currently on the market is around 8-10%. During construction, professionals must cooperate with the sprayer for normal use. A small amount can also be applied manually, and just use putty when applying.

Spray coatings are divided into neutral, acidic, and alkaline materials. When using, select the material suitable for the furnace lining for spraying according to the atmosphere of the furnace lining. Because the furnace lining atmosphere and materials are in the same atmosphere, the furnace lining atmosphere is good and the service life is long.

Rongsheng Refractory Materials Manufacturer is a powerful manufacturer and seller of refractory materials. Our environmentally friendly, fully automatic unshaped refractory material production line provides high-quality refractory lining materials for various industrial kilns. Product quality is guaranteed, and the spray refractory coating formula can be customized. The professional technical and construction team provides pre-sales technology and after-sales construction services for refractory lining solutions. Contact us to get free samples and quotes.