Castables Refractory Archives - Kiln Refractories Blog

Refractory Material Manufacturers Respond – How to Correctly Choose Refractory Castables?

November 30, 2023 KilnRefractory

Refractory castables are divided into acidic, alkaline, and neutral castables according to their resistance to chemical attack. According to the volume density, it is divided into dense castable refractory and light castable. According to the materials used, it is divided into aluminum silicate, magnesium, magnesium chromium, corundum castables, etc. There are many types of refractory castables, and it is difficult to make a choice without clear indicators and operating temperatures. RS refractory material manufacturer responded to “How to correctly choose refractory castables” and gave some more reliable methods for reference.

(1) Refractory castables must meet the requirements of the kiln’s usage environment.

Dense refractory castables have different requirements depending on where they are used. When selecting, it should be selected according to the characteristics of the castable. For parts that come into contact with high-temperature flames, high-temperature-resistant castables should be selected. Castables with high-temperature resistance and strong penetration resistance should be selected for parts that come into contact with high-temperature solutions. The parts that come into contact with slag should use castables that are highly resistant to the chemical erosion of slag. High-strength and wear-resistant castables are used for parts that come into contact with the impact and friction of various materials. For parts with frequent temperature changes, castables with excellent thermal shock resistance should be used. As long as it meets the requirements of the main production conditions, it is a suitable refractory castable.

The main uses of lightweight refractory castables are heat insulation, reducing load-bearing structures, lowering furnace shell temperature, and reducing heat loss, thereby achieving energy-saving effects.

(2) Economy of investment cost of refractory castables.

After determining which refractory castable to choose, it is also necessary to economically reduce costs. For example, if the use temperature is 1500°C, castables with a use temperature greater than 1600°C will not be selected if the castables can meet the working conditions. If high alumina bauxite clinker is used as the main material in the wear-resistant parts to meet the wear resistance requirements, castables with corundum as the main material should not be selected. The main reason is that the price of refractory castables varies greatly depending on the content of the main materials used. There is no need to ignore economic costs in pursuit of high quality. This requirement is especially important for parts that are subject to daily wear and tear.

(3) Particle size selection of refractory castables.

The construction parts of refractory castables may be thick or thin, and the particle size ratios used are different. For example, when pouring a lining with a thickness greater than 100mm, more large-grained critical aggregates need to be added to improve structural strength and wear resistance. The parts with a thickness of 10mm when poured or painted have fewer large particles of aggregate. Avoid adding large aggregates to make them protrude from the lining, which not only affects the appearance but also causes large particles to wear easily in terms of use. This causes holes in the lining, which in turn affects the service life. Depending on the pouring thickness, the pouring method or the smearing method can be used. Therefore, the selection of particle size of refractory castables is also very important.

(4) The shelf life of refractory castables.

The storage time of refractory castables in dry areas is about 6-9 months. Before use, check whether there are any agglomerations. During transportation or handling, the castable will agglomerate due to extrusion. If it can be easily patted away, the use effect will not be affected. However, the shelf life of the castables is a secondary consideration, because the configuration processes of the castables are different and most parts are not in stock. All need to be produced according to user needs and the production process adjusted.

It can be seen from the above that the selection of refractory castables is variable and must be used flexibly. To quickly select castables, it is necessary to mention the specific use location, working conditions, use temperature, pouring thickness, and construction method of the castables. The main thing is to find the right method to choose high-quality refractory castables while reducing costs.

Performance Characteristics of Dense Refractory Castables

Dense refractory castable is a construction material used in high-temperature operations. Its main function is to fill and support the furnace while providing oxidation resistance at high temperatures. Dense castables refractory are further divided into aluminate cement castables, chemically bonded refractory castables, clay bonded refractory castables, low cement series refractory castables, self-flowing castables, and new technology refractory castables. The body density is generally around 1800Kg/m³-3500Kg/m³.

Dense refractory castables are generally used for furnace lining, working layer, and permanent layer. According to the use environment, use location, and use requirements, different refractory castables are used to extend the service life of the castables.

High-temperature antioxidant properties. Medium and Dense castables refractory can withstand high temperatures and high oxidation temperatures, and their oxidation resistance is better than other types of castables. Can be used in high-temperature furnaces for a long time.

Reusability. Medium and Dense refractory castables can be reused, reducing environmental pollution and waste of resources.

Density and weight. Medium-Dense castables refractory have a lower density and weight than other types of castables, making them easier to move and fill within the furnace.

chemical composition. The chemical composition of medium and Dense refractory castables can be adjusted according to different requirements to meet different high-temperature environments and application needs.

Stability and reliability. Medium and Dense castables refractory can withstand high temperatures and high oxidation temperatures and maintain stability and reliability over long periods of use.

manufacturing cost. Medium-Dense refractory castables are more expensive to manufacture than other types of castables, but their performance value and cost of use make them a popular high-temperature building material.

RS Kiln Refractory Factory

RS Kiln Refractory Factory can provide high-quality refractory lining materials for high-temperature industrial furnace linings, including various refractory bricks, refractory castables, refractory plastics, etc. If you need to buy Dense castables refractory, Dense refractory bricks for the working lining of high-temperature industrial furnaces. Please contact us. We can provide you with high-quality refractory materials at competitive prices.

Refractory Castable for All Kinds of Coal-Fired Boilers in Power Plants

June 5, 2023June 5, 2023 KilnRefractory

With the development of modern large power plant boilers, the requirement for refractory material for boiler wall structures has changed greatly. The refractory materials of furnace walls are developed from traditional firebrick to refractory concrete, refractory castable, plastic refractory, refractory ramming material, smearing material, spray coating, and so on. With the development of refractory materials for large power generation equipment and boilers, the use of these materials has promoted the development of refractory materials for domestic boilers. castable refractory for the boiler. Power plant boiler due to different parts of the temperature and use requirements, a boiler has 610 kinds of refractories with different performance requirements.

Refractory Castable for CFB Boilers in Power Plants

Refractory Castables for All Kinds of Coal-Fired Boilers in Power Plants

The furnace type of coal-fired boiler in power plants is related to the coal type. At present domestic refractories can basically meet the needs of various boilers.

The liquid slag-discharging furnace and cyclone furnace are used for burning coal with low melting point ash. Because of the high temperature of the furnace, the refractory should have the characteristics of high-temperature resistance, wear resistance, thermal shock stability, high thermal conductivity, and slag resistance. Generally use silicon carbide ramming material.

The combustion of low-volatile coal generally adopts a “W” flame, and the furnace is equipped with a backburner belt. Adopt wear-resistant, high thermal conductivity, and good thermal shock stability of refractory materials. General selection of silicon carbide, chromium coating material, and high aluminum plastic.

The circulating fluidized bed boiler burns coal with low calorific value and high sulfur content. High ash concentration, high flow rate, and serious wear. General selection of corundum, silicon carbide wear-resistant, refractory castable.

The incinerator of the waste power plant is affected by the burning condition, and the refractory material is required to have fire resistance, volume stability, heat shock resistance, corrosion resistance, high strength, and wear resistance. Therefore, spray coating, castable, silicon carbide brick (board) is selected.

The selection of refractory materials for the boiler, refractory materials with good performance, remarkable effect, and reasonable price. Such as boiler tube furnace wall, furnace top, and flue equipment lining, promote the application of fast hard (micro expansion) refractory castable plastic. The double arch “W” flame furnace flame belt is made of high aluminophosphate combined with refractory plastic and silicon carbide coating. Circulating fluidized bed boiler and HR collection box selection of jade, silicon carbide castable, and plastic.

Strengthen the research and development of new refractories. For example, the development of high-temperature resistance, high strength, and wear resistance of the refractory coating, ramming, and spray coating without heat treatment. To simplify the process and improve the quality of the project. The lightweight castable with fibrous, expanded perlite, and vermiculite gradation was studied.

Refractory Castable Material for Circulating Fluidized Bed Boilers in Power Plants

In the fluidized bed boilers of the power plant, high temperature, high pressure, and erosion are very serious. It requires high-quality refractory castables, resulting in longer life and more efficient vulcanization furnaces in power plants. The specific type and performance requirements should be adjusted according to the actual situation of the boiler and should be used with a firebrick. Please contact Rongsheng Refractory for high-quality monolithic castable refractory for the power plant.

The following information about the use of refractory castables for circulating fluidized bed boilers in power plants is for reference only. Case by case analysis, Rongsheng refractory manufacturers, according to your actual work needs, for you to customize the formulation of amorphous refractory. Burner: refractory castable refractory 120mm +215mm +lightweight castable refractory. Top: Refractory castable, refractory plastic 48mm ~60mm. Manhole door: refractory castable and water-cooled wall flat. Test hole: refractory castable and water wall flat. Boiler roof: refractory insulation slips. Smoke Angle: The refractory castable is water-cooled wall flat. Burner wall: refractory tamping material, refractory plastic. Top of heat seal cover: 20 ~ 40mm aluminum silicate felt + 50 ~ 60mm refractory plastic.

Expansion joint of ceiling pipe: filled with aluminum silicate cotton. Non-thermal seal cover top: 20mm aluminum silicate felt +100mm refractory plastic. Furnace top and top tube: aluminum silicate cotton felt, aluminum silicate tube shell, or silicate composite insulation products. E Gas, water connection box, all kinds of pipe baffle: refractory castable. Sanitary belt: tamper. Slag funnel lining, which requires high strength and good thermal shock resistance. 900 ~ 1200℃, steel fiber high alumina refractory castable. High-temperature furnace smoke pipe lining: aluminum silicate cotton felt insulation layer, refractory layer water glass fast refractory plastic or steel fiber high aluminum cement castable.

RS Steel Fiber Refractory Castable Manufacturer

Special castable for burner; Easy to burn parts: free roasting quick supplement, quick drying castable, outlet pipe, tube wall inner layer: expansion high aluminum castable, fast hard micro expansion plastic; Combustion chamber furnace: wear-resistant castable, slag resistant and wear-resistant castable, steel fiber reinforced castable, far infrared radiation coating, high temperature filling joint pressed into cement; Steering flue: wear-resistant castable; Cyclone separator: wear-resistant castable, corundum high strength wear-resistant castable; Coal nozzle.

Steel fiber reinforced castor refeeder: wear-resistant castable; Diaphragm wall: wear-resistant castable; Water-cooled chamber: wear-resistant castable; Ignition duct: wear-resistant castable; Furnace collection: wear-resistant castable in the furnace.

Rongsheng factory is a strong refractory manufacturer. Professional refractory technical team, environmental protection of automatic amorphous refractory production line. Specializing in the production of various castable refractory for boiler, such as lightweight castable refractory, refractory plastics, refractory ramming materials, high strength wear resistant refractory materials, etc. Please also contact the refractory castable manufacturer to compare RS Refractory Castable with Calderys castable. After all, you can shop around for affordable refractory products. If you also want to obtain better customer service, please choose the strength of Rongsheng refractory manufacturers, +86 185 3831 2977.

What Kind of Refractory Castables Can be Used When the Working Temperature is 1300℃?

April 27, 2023April 27, 2023 KilnRefractory

What kinds of refractory castable should be used when the refractory castable is used at a temperature of 1300°C? This is determined according to the different working conditions of different furnace types. But no matter what castable you choose, the ultimate goal is to save energy, reduce production costs, and prolong the service life of the refractory lining.

When choosing castables for high-temperature industrial furnaces, whether it is to choose castable manufacturers or distributors of monolithic refractory materials. First of all, the fuel used in the high-temperature industrial furnace and the material of the raw materials required in the production process must be considered. And whether there are highly corrosive substances in the raw material composition, it is also necessary to determine whether the corrosive substances are acidic or alkaline. In addition, there are external factors of the furnace type to be considered, whether there is wind speed, erosion and wear caused by mechanical stress, etc.

RS Monolithic Refractory Castable Factory

The furnace temperature of 1300°C is the direct contact temperature of the flame, not the refractoriness. This temperature definition is very important. High alumina castables are also divided into different grades and different substrates. If the castable solidifies too quickly in the early stage, it proves that the amount of cement added is too large, or there is a problem with the control ratio of the binder and the micro-powder, which will affect the strength of the castable later.

If the setting time is too slow, the construction temperature should be considered, and the amount added should be well controlled when adding water. When the temperature is low, the drinking water should be heated to 30°C, and then added to the material and mixed for use. If congealed within 40 minutes. Then bake according to a reasonable baking system to ensure the service life of the refractory castable.

Generally, high-alumina castables can be used for the furnace temperature of 1300°C, but if the corrosion is severe, it is necessary to choose acidic or alkaline corrosion-resistant castables according to the nature of the corrosion. If it is acidic corrosion, you can choose water glass bonded castable or phosphoric acid bonded refractory castable, if it is alkaline corrosion, you can choose high wear-resistant castable. Because the high wear-resistant castable is added with silicon carbide, it can resist erosion and play a role in wear resistance.

Application Advantages of Low Cement Castables

The prominent feature of low-cement castables is their dense and high strength, which brings benefits to use but brings troubles to baking, that is, improper baking, prone to peeling or bursting. Therefore, it is very important to formulate a reasonable oven curve and use an excellent explosion-proof admixture, so that the moisture in the molded refractory castable can be removed smoothly without causing any side effects.

The thermal expansion coefficient of low cement refractory castables shows the characteristics of expansion during the whole heating process. It can be seen that as the heating temperature increases, the thermal expansion rate increases, reaching a value of about 0.68% at 1250 °C. Then it began to shrink slowly, and the thermal expansion rate at 1400°C was 0.43%. When the temperature is 1500°C, the thermal expansion rate returns to 0.5%.

Low-cement refractory castables have a wide range of applications. In industrial kilns such as metallurgy, petrochemicals, machinery manufacturing, electric power, and building materials, such castables have been widely used to replace traditional fired refractory products as linings. Low-cement and ultra-low-cement refractory castables are mainly used as linings of thick dimensions, such as linings for heating furnaces, various heat treatments, electric furnace covers, shaft kilns, rotary kilns, blast furnace tapping hooks, ladles, ladles, etc. The self-flowing low and ultra-low cement refractory castables are mainly used as thin linings and linings of high-temperature refractory components with metal anchors, such as outer linings of water-cooled pipes for heating furnaces, and integral spray gun linings for spray metallurgy.

As the heating temperature rises, the cement stone is gradually sintered, and the crystal form of the castable body begins to transform into mullite crystals. As the temperature continues to rise, the mullite crystals continue to grow, and the matrix glass phase in the castable is in a liquid state, forming a high-temperature ceramic sintered shape, and the strength is significantly improved.

Low-calcium high-alumina cement is a hydraulic material like ordinary cement, and it undergoes hydration reaction and hardening after contact with water. Low cement castable, its main feature is high early strength, 3-7 days room temperature compressive strength can reach more than 30MPa. The disadvantage is that the medium temperature volume stability is poor, and the strength is reduced, and the decline can reach about 40%. Therefore, it is required that the compressive strength at room temperature must meet the requirements of design and national standards. The main factor for the decrease in medium temperature strength is. When the low-calcium and high-alumina cement of the castable body reaches a certain temperature (about 350°C) during the heating process of the heating furnace, the hydrates begin to dehydrate and transform to reduce the cement stone structure, compactness, and strength of the hydrates. The volume of the castable changes and the strength of the castable body drops to a low point at this time and then tends to be stable.

For high-quality refractory manufacturers, please choose RS Kiln Refractory Factory, at sales@kilnrefractory.com to purchase refractory materials with high-temperature resistance of 1300℃.

What is the Bulk Density of Refractory Castables?

April 29, 2021 KilnRefractory

What is the bulk density of refractory castables? This is mainly based on the specific construction site and high-temperature resistance requirements. The preparation of refractory castables is customized according to the index requirements provided by users. These indicators mainly include refractoriness, material chemical composition, bulk density, compressive strength, flexural strength, and so on. Bulk density or bulk density is one of the important indicators, which intuitively reflects the compactness of refractory products and characterizes the mass of refractory materials per unit volume. It is an important measure of the quality level of refractory raw materials and dense refractory products.

The Significance of the Bulk Density of Refractories

Bulk density is the ratio of the dry mass of the refractory material to the total volume. The higher the volume density, the higher the density. The bulk density of the material has a significant effect on many other properties, such as porosity, strength, corrosion resistance, load softening temperature, wear resistance, thermal shock resistance, etc. For lightweight thermal insulation materials, such as thermal insulation bricks, light weight castables, etc., the bulk density is also closely related to its thermal conductivity and heat capacity. Generally speaking, the bulk density of the material is high, which is beneficial to its strength, corrosion resistance, wear resistance, and load softening temperature.

Therefore, with regard to the volume density of refractory castables, each manufacturer has its own standards. In order to increase the bulk density of refractory castables, a reasonable ratio of multi-stage particles should be adopted, which should meet the requirement of “large at two ends and small in the middle”. That is, under the premise of not affecting the performance of refractory castables, adding fine powder matrix or using silicon powder to replace part of the binder material, reducing the amount of water added to increase its bulk density.

Bulk Density of Refractory Castables

The bulk density of refractory castables is different depending on the location of use. It is mainly divided into two parts, namely dense refractory castable and light refractory castable. Dense refractory castables are used for parts that are exposed to high temperature, molten slag, scouring, and thermal shock stress. The use of castables with high bulk density can improve structural strength, wear resistance, slag penetration resistance, thermal shock resistance, etc. Lightweight refractory castables are only used for the material of the thermal insulation layer close to the furnace shell, with the main purpose of thermal insulation. Its strength is low, density is small, porosity is high, and it can’t touch slag or chemically corroded parts.

The density of dense refractory castables configured by different materials is different. For example, the bulk density of clay refractory castables is 2.1~2.2 g/cm3. The bulk density of high-aluminum refractory castables is generally 2.5~2.85 g/cm3, which increases with the increase of aluminum content. The bulk density of clay low cement castable is 2.2~2.3g/cm3. The bulk density of corundum low cement castable is 3.0~3.1g/cm3, etc.

The lightweight refractory castables configured by different materials are different. For example, the bulk density of lightweight floating bead castables is 0.6~1.0g/cm3. The bulk density of the castable prepared with clay porous clinker is 0.8~1.3g/cm3. The volume density of the castable configured with mullite porous clinker is 1.2~1.6g/cm3, etc.

In short, the bulk density of refractory castables depends on the temperature and location of use. For example, the bulk density of high alumina refractory castable is 2.5g/cm3 or 2500kg/m3, which means that a cubic high alumina refractory castable weighs about 2.5 tons. The bulk density of lightweight castables is 0.8g/cm3 or 800kg/m3, representing a cubic weight of 0.8 tons. The volume density of refractory castables is the specific manifestation of bulk density, and the weight of materials required for construction parts can be calculated through this index. Refractory castables will inevitably be lost during the construction process. In order to prepare all the materials at one time, the total quantity can be increased by about 0.5 tons to avoid suspension due to insufficient construction materials.

Refractory Castable Manufacturer and Sales Manufacturer

This is the introduction about the appropriate density of the castable. I hope it will be helpful to you. If you have any other questions, please feel free to contact us. Purchasing suitable refractory materials for the kiln lining, and looking for a suitable refractory lining material solution, the strength of the Rongsheng refractory manufacturer is your reliable guarantee. Our experienced technical team and our advanced refractory production line have won us many return customers and long-term cooperative customers. If you have any questions about refractory materials or refractory lining materials, please contact us or follow our blog.

Detailed Information of Alumina Silicate Refractory Mortar

July 8, 2020 KilnRefractory

Alumina Silicate Refractory Mortar includes clay, mullite, and high alumina refractory mortar. All alumina silicate refractory mortar is added with clay, the main purpose is to improve its adhesion.

The alumina silicate refractory mortar is made of 160-200 mesh powder. In general, different grades of refractory mortar are based on the grade of alumina silicate fire brick built with a refractory lining. For example, 75 high-alumina bricks, the refractory mortar with the aluminum content of 65 is used, and the 65-high-aluminum bricks are prepared with 55-60 high-alumina mortar. High alumina bricks with an alumina content of 55 are formulated with a slurry content of 45-50. Some refractory bricks with high alumina content also need to add corundum powder when configuring brick fire clay to meet the needs of brick distribution.

If it is used in the blast furnace hearth and other parts, phosphate combined refractory mortar is also used. In this way, the service life can be more guaranteed, and the gray seam does not shrink during use.

RS Castable Refractory Mortar Manufacturer

Some of the refractory mortar used in large-scale blast furnaces, many of which are added with andalusite, quartz powder, or kyanite, is to ensure that the crevice does not shrink when sintered.

Some refractory mortars with low aluminum content generally do not add a binder. However, in order to improve the bonding strength, a certain proportion of bonding agents will be added, such as phosphoric acid, water glass, polyphosphate, etc. With the change of the addition of the binding agent, the bonding strength also changes after firing, but the strength at the high temperature and hot state is opposite. Adding the binding agent will cause the liquid phase in the refractory mortar to increase at high temperatures. Sodium polyacrylate and methylene naphthalene sulfonate are added to the binder to prevent solid-liquid separation of the prepared refractory mortar during standing. The addition of methylcellulose can also be prevented.

Aluminum silicate refractory mortar belongs to a water-based refractory mortar and cannot be built with carbon bricks or the like. Because the water vapor volatilized by the water-based mortar in the oven and use has a destructive effect on the carbon brick masonry. Therefore, the non-aqueous refractory mortar is used. learn more from Rongsheng Refractory mortar manufacturer.

Volume Stability of High Alumina Castables

June 30, 2020June 30, 2020 KilnRefractory

For a long time, high silica bricks have been used for tundish refractory. Today, low-cement and high alumina castables have widely replaced high-silica bricks by increasing life to reduce costs and improve working conditions. Because MgO coating must be applied to the tundish permanent castable. For high aluminum castables, volume stability is very important.

Although high-alumina refractory castables have higher mechanical strength and better corrosion resistance, cracks occur due to insufficient volume stability. Metal attachments penetrate through the cracks, resulting in a reduction in their life and an increase in local maintenance.

Performance of Light-weight High Alumina Castable

High-performance light-weight high-aluminum castable improves its strength and reduces thermal conductivity. The castable has better construction performance and higher medium-high temperature strength. The compound combination method of hydration combination and coagulation combination can improve the normal temperature and high-temperature performance of the castable. The developed high-performance light-weight high-aluminum castable has low thermal conductivity, high high-temperature strength and volume stability. It is used in high-temperature parts of various industrial furnaces from 1200 to 1500 ℃ and has achieved good results. The energy-saving effect is obvious.

Experiments have shown that:

(1) The method of adding ultra-fine alumina powder can improve the construction performance of high-aluminum castables. However, as the ultrafine alumina content increases, the volume stability after firing decreases.

(2) If mullite is added to the matrix instead of alumina, the volume change after firing will decrease, but the construction performance will also decrease with the increase of mullite content.

(3) When andalusite is added to the matrix, the construction performance is reduced a lot, but the volume stability is greatly improved. Therefore, if the plasticity of andalusite is improved, andalusite is a good material of choice for the matrix of high-alumina castables that require high volume stability.

The high-performance light-weight high alumina castables are fully considered, and various related factors that affect the castables are fully considered. In the case of reducing production costs and meeting the conditions for the use of castables, optimize the composition and configuration of castables, formulate a reasonable production process, and strengthen process control. Castable manufacturers have produced a series of high-performance light-weight high-aluminum castables with a bulk density of 1.30 g/cm3, 1.50 g/cm3, and 1.80 g/cm3 to meet various working conditions.

Application of Lightweight High Alumina Castable

The performance of lightweight high-aluminum castables determines the energy-saving effect of thermal kilns. With the rapid development of various industries, the number and scope of light-weight castable applications are gradually expanding. From the permanent layer, the heat insulation layer to the working layer, from the low-temperature part to the high-temperature part, the transition from low load environment to high load environment. insulating castable. At present, the technology of lightweight high-alumina castables used in the working layer in the middle and low temperature (<1 200 ℃) and high temperature (>1 500 ℃) parts has basically matured performance. However, the performance of lightweight castables used in the medium and high-temperature range (1 200 to 1 500 ℃) needs to be improved to meet the new requirements for the use of lightweight high aluminum castables.

Rongsheng Refractory Castable Manufacturer

Rongsheng refractory castable manufacturer has a fully automatic refractory castable production line. The high-performance light-weight high alumina castables produced by Rongsheng are characterized by high strength, low thermal conductivity, and excellent construction performance in the working environment above 1200 ℃. And it has great significance in the research and application of energy-saving technology, energy-saving equipment, and energy-saving materials.

Application of Corundum Refractory Castable

March 30, 2020 KilnRefractory

Corundum refractory castables have a higher aluminum content than other castables. Therefore it has higher abrasion resistance and mechanical strength. Speaking of the application of corundum refractory castables, it is mainly used for lining materials of various furnaces such as boilers, blast furnace hot blast stoves, heating furnaces, ceramic kiln and so on. In other words, it is used in parts with more mechanical shock and wear. In addition, this castable is mainly used in thermal equipment such as synthetic ammonia gasification furnaces and carbon black reaction furnaces, and can also be used in repairing furnace linings. RS refractory castable manufacturers will introduce you the application of corundum refractory castable. Rongsheng refractory manufacturer’s refractory castable products have guaranteed quality and strong performance.

The Main Application of High Purity Corundum Refractory Castable

High-purity corundum refractory castables are mainly used in large and medium-sized ultra-high power electric furnace cover triangle areas and LF refining ladle covers. It is mainly used to produce breathable bricks and nozzles. It is widely used in the steelmaking industry, and SH benefits and economic benefits are very good.

High-purity corundum (white corundum, brown corundum) refractory castable is an excellent refractory material, mainly used in the working layer of large ladle. It can be pre-made into bricks or can be cast in one piece. The proportion of the latter construction method is increasing. The damage of high-purity corundum refractory castables during use is mainly thermal spalling. However, if microcracks occur in the ladle material used, it will cause the molten steel to penetrate the molten steel during the cooling process, causing the ladle to peel off.

Corundum Refractory Castable Features

High-purity fused white corundum, plate-shaped corundum and dense corundum are used as aggregates, dense corundum and white corundum are used as powders, and appropriate amounts of active SiO2 fine powder and α-Al2O3 powder are added, and a dispersant and a water reducing agent are added at the same time. With the proper formula and molding process, high-purity corundum refractory castables with a life span equal to or exceeding that of imported similar products can be produced.

The main component of corundum is α-Al2O3, which belongs to the triangular crystal system. The crystals are short columnar, the true density is 3.85 ~ 4.01g / cm ~ 3, the hardness is 9, and the melting point is about 2050 ℃. In addition, corundum itself has high thermal conductivity and insulation, good chemical stability and ability to resist reducing agent action. Therefore, corundum can be used as a raw material for advanced refractories. Adding corundum to the refractory castable can make the aluminum content of the castable reach more than 90%, which improves the hardness and strength of the castable. But adding corundum and mullite to the castable, the aluminum content can reach 99%, the hardness, strength and wear resistance can reach a certain range, and the application effect is also significant.

Corundum refractory castable manufacturer

Rongsheng refractory manufacturer, specializing in the production of refractory castable, high alumina castable, corundum castable, mullite castable, rigid fiber castable and other castables. The company has passed ISO international 9001 quality system certification. The product quality conforms to international standards and is sold throughout the country and exported to Southeast Asia, South America, Africa and other countries and regions. We provide customers with guaranteed services: reliable quality, timely delivery and reasonable prices. Save your money without affecting product quality.

Advantages and Disadvantages of Silicon Carbide Castable Refractory

December 21, 2019 KilnRefractory

In the production and sales of unshaped refractories, RS refractories manufacturer has concluded through the accumulated experience of more than ten years. When using silicon carbide castable refractory, not only the Advantages and disadvantages of silicon carbide castable refractory, the refractory castable price, but also the working environment of the refractory material need to be determined.

Silicon carbide (SiC) is an excellent wear-resistant and refractory raw material. In order to improve the wear resistance when configuring refractory castables, in addition to corundum, an appropriate amount of silicon carbide can be added to improve its wear resistance. Silicon carbide is made of natural silica and coke with SIO2 content greater than 97% as basic synthetic raw materials, and is synthesized at 2000-2500 ° C using an electric furnace. It has the advantages of small thermal expansion coefficient, Mohs hardness 9.0 ~ 9.5, and strong chemical stability.

Silicon Carbide Castable Refractory Advantages

The biggest advantage of silicon carbide refractory castables is that it has high thermal conductivity, low thermal expansion, and does not react with slag. It has been used as a slag reaction and high temperature spalling kiln parts very early.

Silicon Carbide Castable Refractory Disadvantages

The biggest disadvantage is that, it is chemically unstable under certain atmospheres. Silicon carbide castable refractory is easy to be corroded in the atmosphere of oxidizing gas such as (oxygen, water vapor, carbon monoxide, carbon dioxide) and iron oxide. And it is easy to be oxidized and decomposed in the molten iron and vacuum.
Another disadvantage, due to the poor water solubility of silicon carbide, in water-based monolithic refractories such as castables, the silicon carbide refractory castables may have poor fluidity, resulting in poor density of the silicon carbide refractory castables.
The third disadvantage is the lack of sintering and difficulty in obtaining high strength. However, silicon carbide refractory castable are sometimes difficult to cause over-sintering and shrinkage, but they have advantages in unshaped refractories.

In the actual environment of the use of unshaped refractory castables, Advantages and disadvantages of silicon carbide castable refractory may have an impact on specific production. If we can carry out the production operations correctly and carry out the correct construction of refractory castables, we can avoid bad situations. Therefore, the construction party must follow the construction instructions for refractory castables. The production process also requires careful operation. If you want to know more about silicon carbide castable refractory, please contact us. Rongsheng refractory manufacturer is looking forward to cooperate with you.

Castable Refractory Mortar

October 23, 2019 KilnRefractory

The castable refractory mortar consists of refractory powder, binder and additive. Almost all refractory materials can be made into powders used to make refractory mortar. The particle size of the refractory mortar will vary according to the requirements of use. The ultimate particle size is generally less than 1 mm, and some are less than 0.5 mm or less.

Forming Method of Castable Refractory Mortar

Almost all refractory materials can be made into powders used to make castable refractory mortars.

The ordinary refractory mortar made of refractory clinker powder and appropriate amount of plastic clay as a binder and a plasticizer has a low room temperature strength and a high strength under the formation of a ceramic bond at a high temperature.

A chemically bonded refractory mortar using a hydraulic, gas-hard or thermosetting bonding material as a binder, hardens before a certain chemical reaction occurs before the ceramic bonding temperature is formed.

High Alumina Castable Refractory Mortars

Refractory Mortar Characteristics and Applications

Good plasticity and convenient construction;
Strong bonding strength and strong corrosion resistance;
High refractoriness, up to 1650 ° C ± 50 ° C;
Good resistance to slag invasion;
Good thermal exfoliation.
Bulk density: 1.8-2.2g/cm3.

The castable refractory mortar is mainly used in coke ovens, glass kiln furnaces, blast furnace hot blast stoves, and other industrial kiln furnaces. The applied industries are: metallurgy, building materials, machinery, petrochemical, glass, boiler, electricity, steel, cement, etc.

Refractory Mortar Selection

According to the material, refractory mortar can be divided into clay, high-aluminum, siliceous and magnesia refractory mortar. When selecting the material of the refractory mortar, it should be considered to be consistent with the material of the refractory product of the masonry. In addition to the crevice material, the castable refractory mortar can also be used as a protective coating for the lining by smearing or spraying.

Castable Refractory Mortar Manufacturer

Rongsheng is a manufacturer of refractory materials with rich experience in production and refractory lining construction. Our castable refractory production line is 150 tons per day, and our refractory brick products are also exported to 62 countries. And received the customer’s praise! Our refractory technology team provides custom refractory brick and castable products for a wide range of thermal equipment. Looking forward to your order and visit! Website: kilnrefractory.com

Casting Refractory Cement

October 16, 2019 KilnRefractory

Refractory castables are made of refractory cement (10%~15%, weight ratio) and refractory aggregates, so casting refractory cement is also an indispensable part.

The Role of Casting Refractory Cement

The role of casting refractory cement in refractory castables is the binder. It affects the setting time of the refractory castable. At the same time, due to the nature of the castable refractory cement itself, it also causes a series of performance degradation of the refractory castable.

Main Properties of Castable Refractory Cement and Its Effect on Refractory Castables

In order to completely hydrate the cement, excessive addition of water (10%~15%) is required to cause the ceramic refractory castable to have a high porosity and a decrease in density.
Calcium aluminate hydrate has strong dehydration and recrystallization effects in the middle temperature stage, which destroys the microstructure of the hard spots in the castable, and the strength of the refractory castables drops sharply in the middle temperature stage.
The cementitious binder brings more calcium into the castable, which leads to a decrease in the load-softening temperature of the ceramified refractory castable, and the thermal shock stability index deteriorates.

Low Cement Castables Properties

In view of the problem of poor high temperature performance of ordinary refractory castables, low cement refractory castables effectively avoid the regret of high temperature performance. The low-cement refractory castable, often mentioned, has a cement content of less than 8%, while less than 4% is called an ultra-low cement refractory castable.

In contrast, the deficiencies described above for conventional refractory castables translate into the advantages of low cement refractory castables. Its structure is dense. The apparent porosity is low, the refractoriness is high, the load softening temperature is high, the high temperature strength is high, and the thermal shock stability is good. However, due to its low cement content, the condensation time is long, and the early strength is low, which is particularly unfavorable in winter and low temperature conditions. Therefore, pay full attention when construction lining.

Casting Refractory Cement Manufacturer

As a manufacturer of refractory materials, Rongsheng is committed to the production and development of refractory bricks and refractory castables. It is designed to provide customers with refractory castable products that meet the needs of customers’ thermal equipment. Our casting refractory cement with low cement Can also help you more. Email to Us for free quote.