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.

Rongsheng Refractory Plastic Manufacturer

Refractory plastic is composed of refractory (bauxite) aggregate and refractory powder, mixed in proportion, adding binders such as plastic white mud or clay and an appropriate amount of plasticizer. It is an unshaped refractory material that is in the form of bulk material or paste and maintains high plasticity for a long time.

Classification of refractory plastics: According to the types of refractory aggregates, they are divided into clay, high alumina, mullite corundum, chromium, silicon carbide, and zirconium. According to the type of binder, it is divided into composite binders such as raw clay and aluminum sulfate, phosphoric acid, phosphate, water glass, and resin. According to the normal temperature hardening properties, it is divided into air-hardening and thermosetting refractory plastics.

RS High Alumina Plastic Refractory

Refractory Plastic Properties

To ensure normal use at high temperatures and smooth construction, refractory plastics should have the following basic characteristics:

1. It has a shelf life of construction time to ensure that the molding performance remains unchanged during the specified storage period.

2. It has good plasticity for easy construction.

3. It has good strength after curing at room temperature so that the frame can be dismantled after construction.

4. It has good high-temperature volume stability to prevent damage to the furnace lining structure due to excessive deformation.

Applications of Refractory Plastics

Refractory plastics are mainly used in the linings and maintenance of furnaces, cyclones, superheaters, flues, etc. of various power station boilers, and in the linings of heating furnace roofs, water-cooled walls, etc. Materials can be divided into high aluminum, clay, corundum, corundum silicon carbide, silicon, magnesia, chromium, etc. According to the classification of binders, there are white mud binders, aluminum phosphate binders, water glass binders, sulfate binders, aluminate binders, etc.

Advantages of Rongsheng Refractory Plastics

Application Advantages of Rongsheng Refractory Plastics

The characteristic of refractory plastic is that it can be constructed into any shape and the construction period is short. It can be constructed by ramming, or it can be repaired according to the damaged location. Moreover, it can be put into use directly according to the furnace temperature without baking. It is a good repair material.

Fire-resistant plastic has good wear resistance, strong plasticity, and good bonding properties. It is mostly used in circulating fluidized bed boilers or heating furnaces. Plastics can be produced in many forms during the production process. If the construction is to be put into use immediately, one-third of the cementing material can be added during production. Trapped materials first, go to the construction site and add the other two-thirds of the PA80 glue, and then the construction can be started. You can also add all the glue into the material, but the packaging must be scientific. Open the plastic packaging at the construction site and put it into use.

The raw material of refractory plastic can be corundum, burnt gemstone, or high-aluminum aggregate. It can be made into plastics of different grades and qualities. However, the cementing material used must be PA80 glue. Glue is made by boiling aluminum dihydrogen phosphate and phosphoric acid. It can be added first or on-site. If it is added on-site, there still needs to be a process of trapping the material to achieve the best results.

Different grades of refractory plastics are determined according to the furnace lining atmosphere, temperature, and wear resistance of the used parts. If the temperature is low, materials suitable for the temperature can be made and produced, and the price is relatively cheap. If the temperature is high or too high, corundum or even zirconium corundum must be used to make it meet the needs of the furnace lining.

The function of refractory plastic is that it has strong plasticity and can be used on the stovetop. It can also be used for pounding on the furnace wall.

To purchase high-quality refractory materials and refractory plastic products, please contact us. Get free samples and quotes.

High Performance Lightweight High Aluminum Castable

To improve the energy-saving effect of thermal kilns, the number and scope of applications of lightweight castables are gradually expanding. From the permanent layer, the insulation layer to the working layer, it extends from the medium and low-temperature areas to the medium and high-temperature areas and transitions from a low-load environment to a high-load environment. At present, the technical performance of lightweight high-aluminum castables used in working layers at medium-low temperatures (<1 200°C) and high temperatures (>1 500°C) has been basically mature. However, the performance of lightweight castables used in the medium and high-temperature range (1 200 ~ 1 500 ℃) needs to be improved. To meet the new requirements for the use of lightweight high-aluminum castables, it is first necessary to understand the impact of the selection and configuration of lightweight aggregates on their performance. RS refractory material manufacturer can provide high-quality refractory lining products for high-temperature industrial furnace linings.

Lightweight High Aluminum Castable

The raw material configuration of traditional lightweight high-aluminum castables mainly uses lightweight aggregates and heavy fine powders. The lightweight aggregate used has larger pore diameters and lower strength, so the thermal conductivity of the lightweight castable is higher. At the same time, the low strength of the aggregate affects the overall strength of the lightweight castable, limiting its use at higher temperatures. Therefore, microporous aggregates and high-strength aggregates are used. The raw materials used mainly include microporous lightweight mullite and complex-phase hollow spheres. High alumina bauxite, floating beads, kyanite, silica micro powder, alumina micro powder, pure calcium aluminate cement, raw bauxite powder, andalusite, pore-forming agent D, pore-forming agent C, etc.

The Choice of Lightweight Aggregates

To meet the construction and high-temperature performance of lightweight castables, lightweight mullite, and complex-phase hollow balls are selected as lightweight aggregates. Multiphase hollow spheres were used to gradually replace lightweight mullite to study the effect on the properties of the castables. The wall thickness of the multiphase hollow spheres is 0.3~0.5 mm, the particle size is 3~7 mm, and its packing density is 0.60 g/cm3. The packing density of microporous mullite is 0.80 g/cm3.

Effect of adding amount of multi-phase hollow spheres on the volume density of castables

When the amount of multiphase hollow spheres increased from 0 to 40%, the bulk density of the sample dropped from 1.86 g/cm3 to 1.68 g/cm3 after baking at 110 °C × 24 h. The bulk density also shows the same trend after high-temperature firing. Since the packing density of the composite hollow spheres is smaller than that of the lightweight mullite aggregate, the bulk density of the castables shows a downward trend as its addition amount increases. That is, the effect of complex-phase hollow balls on reducing the volume density of castables is greater than that of lightweight mullite.

Effect of the Adding Amount of Complex Phase Hollow Balls on the Normal Temperature Compressive Strength of Castables

The changing trend of normal temperature compressive strength of castables after adding different proportions of multi-phase hollow spheres. As the amount of composite hollow balls increases, the normal temperature compressive strength of the castables after baking and high-temperature firing shows an upward trend. Since the strength of the composite hollow sphere, aggregate is higher than that of the lightweight mullite aggregate, and the surface of the composite hollow sphere is dense, its water absorption rate is lower than that of the lightweight mullite aggregate. At the same time, the spherical aggregate is beneficial to improving the fluidity of the castable, reducing the amount of water added to the castable, and is also beneficial to improving the strength of the sample. Therefore, the reinforcing effect of complex hollow spheres on castables is greater than that of light mullite.

Effect of the Adding Amount of Complex Phase Hollow Spheres on Thermal Conductivity of Castables

As the amount of multiphase hollow spheres increases, the thermal conductivity of the sample shows a downward trend. Since the complex-phase hollow balls have a hollow structure, the air is enclosed in the holes, which has a good heat insulation effect. Therefore, the thermal conductivity of the castable decreases after adding complex-phase hollow balls. Since the pore diameter of the multi-phase hollow sphere is larger, the effect of convective heat transfer will increase at high temperatures. As a result, the effect of reducing the thermal conductivity of the castable at 1000°C is not as obvious as that at 700°C.

Microporous lightweight mullite aggregate is beneficial to reducing the thermal conductivity of castables, but its strength is low. Complex-phase hollow spheres are beneficial to improving the strength of castables, but their effect on reducing thermal conductivity is limited. Due to the low density of composite hollow spheres, taking into account the uniform dispersion of different aggregates and taking into account various properties, the appropriate addition amount of both aggregates is 20% to 30%.

To purchase high-quality lightweight high-aluminum castables, please contact Rongsheng Refractory Materials Manufacturer. Our refractory products are of reliable quality and our after-sales service is guaranteed.

Aluminum-Magnesium Castables Combination Methods

 Aluminum-magnesium castable is a refractory castable with bauxite and magnesium oxide as its main components. It is widely used in the industrial practice of out-of-furnace refining and ladle refractory materials. The MgO can be added in the form of magnesia or pre-synthesized spinel. Aluminum-magnesium castables can be divided into different types. According to different raw materials, it is divided into high-purity corundum-spinel castables and low-purity bauxite-spinel castables. According to the different ways of introducing spinel, it can be divided into aluminum-spinel castable (Al2O3-MA castable) and aluminum-magnesium castable (Al2O3-MgO castable). According to the bonding method, it can be divided into cement-bonded, hydrated bonded, silica powder bonded, magnesium silicon water bonded, and other castables.

Aluminum-Magnesium Castables

How to Combine Aluminum-Magnesium Castables

Binders are also an important component of aluminum-magnesium castables. The bonding methods used in aluminum-magnesium castables are generally calcium aluminate cement bonding, silica powder bonding, hydrated alumina bonding, sol bonding, magnesium silicon water bonding, etc.

(a) Cement bonding

In the early stages of the development of aluminum-magnesium castables, pure calcium aluminate cement was used for bonding. This is because cement calcium aluminate reacts with Al2O3 in the matrix to form CA6, which is a highly refractory phase. However, as the amount of cement added increases, the fluidity of the castable decreases. At the same time, due to excessive CaO content at high temperatures, it will react with SiO2, Al2O3, and MgO in the matrix to form a low melting phase. As a result, the high-temperature performance of the castable is reduced. Zhang Wenjie et al. studied the effect of the amount of water added to cement on the thermal expansion behavior of aluminum-magnesium castables after high-temperature firing. The results show that as the amount of cement added increases, the CA2 and CA6 phases in the sample increase, and the linear change rate of the sample after high-temperature heat treatment increases. Gu Huazhi et al. studied the effects of silica powder, magnesia, and cement on the properties of high-purity aluminum-magnesium castables. Studies have pointed out that pure calcium aluminate cement and Al2O3 fine powder in the matrix begin to react at about 1000°C, and the reaction generates CA2 and CA6. The reaction is accompanied by volume expansion, which can reduce the strength ratio after high-to-medium temperature firing and also contribute to the improvement of the high-temperature performance of the sample.

(b)MgO-SiO2-H2O combination

There are many studies on MgO-SiO2-H2O bonding and condensation bonding. The combination of MgO-SiO2-H2O is used in aluminum-magnesium castables. On the one hand, due to the polymerization of SiO2 gel formed by the interaction between SiO2 powder and water, the amount of water added is reduced and the fluidity of the castables is greatly improved. On the other hand, the combination of MgO-SiO2-H2O can inhibit magnesia hydration. However, if too much silica powder is added, it will form a low melting point phase with impurities in the matrix. At the same time, the forsterite phase formed by the reaction of magnesia and silica powder in the matrix has poor thermal shock stability at high temperatures.

What is Lightweight Insulating Refractory Castable - RS Refractory Materials Manufacturer

 Lightweight castables are lightweight, have low thermal conductivity, are easy to use, and are cheap. Lightweight castables are also continuously developed according to the different needs of the market. Composite lightweight refractory castables are continuously developed to meet the use of furnace linings.

What is Lightweight Insulating Refractory Castable?

Lightweight Insulating Refractory Castable is a refractory castable with lightweight, high strength, and excellent thermal insulation properties. It is mainly composed of lightweight aggregates (such as perlite, vermiculite, etc.), high-temperature stable materials, binders, and additives.

lightweight insulating refractory castable

Introduction to Lightweight Insulating Refractory Castables

Lightweight insulating refractory castables have many advantages, such as low thermal conductivity, low heat capacity, good thermal insulation properties, earthquake resistance, impact resistance, erosion resistance, etc. It is widely used in various high-temperature industrial equipment, such as industrial furnaces, heat treatment furnaces, steel furnaces, glass melting furnaces, etc. To improve the energy efficiency of equipment and reduce energy consumption.

According to the material composition and performance characteristics of lightweight insulating refractory castables, they can be divided into different types. Such as perlite lightweight heat-insulating refractory castables, vermiculite lightweight heat-insulating refractory castables, high-aluminum lightweight heat-insulating refractory castables, etc. Each type of lightweight insulating refractory castable has its own unique characteristics and scope of application, and users should choose according to specific circumstances.

When using lightweight insulating refractory castables, you need to pay attention to the following points:

The mixing ratio. The mixing ratio of lightweight insulating refractory castables should be in accordance with the instructions for use. Different types of lightweight insulating refractory castables have different mixing ratios, and users should choose according to specific conditions.

Construction method. The construction method of lightweight insulating refractory castables can be selected according to specific conditions, and methods such as manual construction, mechanical construction, and pumping construction can usually be used. Different construction methods will affect the density and uniformity of castables.

maintenance. Lightweight heat-insulating refractory castables should be kept moist during the curing period, and the curing time is generally more than 24 hours. During the curing period, it is necessary to prevent the castable from drying out prematurely and causing cracking.

lightweight high-strength insulating refractory castable

Lightweight Refractory Castables with a Bulk Density of Less than 1.5g/cm3

Refractory castables with a bulk density of less than 1.5g/cm3 are lightweight refractory castables. Lightweight refractory castables mainly play the role of thermal insulation. Refractory castables with a bulk density greater than 1.5g/cm3 and less than 1.8g/cm3 can be called semi-lightweight castables. Castables greater than 1.8 are heavy castables.

The raw materials of lightweight castables are lightweight aggregates and powders added in proportion, and the binding agent is also combined with high alumina cement. There is also a combination of water glass and phosphoric acid. However, the amount of binder added to lightweight castables is large, and the proportion of water added during construction is also larger than that of heavy castables.

The characteristics of lightweight castables are low density, lightweight, low thermal conductivity, and good heat insulation effect. There are many varieties of lightweight castables, and their properties can be divided into neutral and acidic.

Application of Lightweight Refractory Castables in Kiln Linings

The lining of the kiln is basically equipped with a heat insulation layer. The lightweight castable used in the heat insulation layer cannot directly contact the flame. The outer layer of the insulation layer usually has castables or refractory bricks for the working layer. Lightweight refractory castable has a good heat insulation effect, slow heat dissipation, and a good heat preservation effect. And it (http://www.aluminabricks.com/refractory-castable/lightweight-refractory-castable/) can save the fuel used by the kiln. In different kiln linings, different lightweight castables or lightweight castables with different properties are used.

Some high-grade lightweight refractory castables can also be used as the working layer in the furnace lining. For example, acidic acid-resistant lightweight castables with a specific gravity of 1.5 can be used in chimneys or flues, and the effect is quite good. Using this lightweight castable will make the chimney lighter and reduce stress. There is also an alumina hollow ball refractory castable, which is a high-end material among lightweight castables. Can be used within special lightweight kiln linings that are not only high-temperature resistant but also lightweight.

To purchase high-quality lightweight refractory castables, please choose Rongsheng Refractory Materials Manufacturer. We can provide you with comprehensive refractory lining material services and good customer service to ensure long life and efficient operation of high-temperature industrial furnace linings.

Precautions for Using Ladles

When the ladle is used for the first time, all parts of the ladle must be thoroughly inspected. Parts such as gantry hooks, various protective devices, and safety forks should be inspected in particular detail. If damage is found, it should be replaced in time. The steel ladle must be inspected with 2 times the load during initial use.

Precautions for Using Ladles

Precautions Before Using the Ladle

Repair of ladle lining. Refractory materials, including refractory bricks, refractory mortar, and refractory mud, should be appropriately selected according to the type of molten steel. For example, ordinary carbon steel uses silicon refractory materials; ordinary alloy steel uses aluminum refractory materials; manganese steel uses magnesium refractory materials.

When using a plug-rod ladle, the ladle nozzle and refractory layer must be constructed in the following order.

(1) Install the sprue brick at the nozzle at the bottom of the package. The sprue brick should be paired with the plug brick and ground before installation.

(2) Install the seat brick.

(3) Use refractory bricks to build the bottom and walls of the ladle. The bottom part of the bag should be sloped 1/20 towards the water outlet. For the used package body, if the corrosion of the refractory layer is not large, you can only replace the refractory bricks at the nozzle and repair part of the refractory layer.

Refractory Bricks for Steel Ladle

(4) Before using the plug rod, the resistant material must be constructed in the following order. Insert the stopper rod through the ground stopper brick and secure it in place. Place the sleeve brick on the plug rod, and fill the space between the sleeve brick hole and the plug rod with dry fine sand or asbestos powder. The contact surfaces of plug head bricks and sleeve bricks should be coated with refractory mud. Add a pressure cap to the end of the sleeve brick, and use a nut to tighten the sleeve brick through the gland.

Installation of sliding spouts. First, install the sliding nozzle well bricks, and then build the refractory material according to the specified thickness of the refractory material.

Ladle baking

Install the plug rod filled with refractory material on the cross arm. During installation, the concentricity of the plug brick and the sprue brick must be adjusted to ensure sealing. After the adjustment is completed, use nuts to reliably fix the plug rod and the transverse hip.

After assembly, the newly repaired refractory ladle should be thoroughly baked 6 hours before use. The baking temperature should be gradually increased from low to high (800℃, constant temperature for 1 hour).

Lower the hanger while the ladle is baking. The drying bag can be used with gas or natural gas. The baking time of used ladles can be shortened. However, the baking time should not be less than 2 hours, and the baking temperature should not be lower than 800℃.

Precautions for Casting Use

1. Before casting, first check whether the safety fork is reliable.

2. Align the pouring opening of the pouring ladle with the opening of the pouring cup of the mold.

3. Before pouring, use the lever to press the plug rod and loosen the locking bolt at the same time to make the pouring ladle in the poured state. When pouring, slowly lift the plug rod, and the molten metal will flow out from the bottom nozzle. The greater the lifting distance of the stopper rod, the greater the flow rate of molten metal. Therefore, the pouring speed can be controlled using a lever.

4. After pouring, check whether the sprue bricks, plug bricks, and sleeve bricks at the nozzle are severely corroded, cracked, or otherwise damaged. If it is damaged, it should be replaced. If it is not damaged, the adhered metal residue or other adherents should be cleaned and maintained for use. Under normal circumstances, the sprue bricks, plug bricks, and sleeve bricks need to be replaced after one package of molten steel.

5. When using the sliding nozzle ladle, pay attention to the drainage sand in the nozzle. When pouring a casting, first open the sliding nozzle mechanism to release a portion of the molten steel (release the drainage sand). Prevent the drainage sand from rushing into the casting and affecting the quality of the casting.

After the ladle is used, the bad refractory materials should be removed and the refractory materials should be rebuilt. At the same time, inspect the pouring ladle, including hoists, lifting rings, beams, safety devices, stopper rods stopper rod driving devices, and sliding nozzle devices.