Month: October 2019

High Quality Chrome Bricks

KilnRefractory

Chrome bricks are refractory material made of chrome ore with a chromium oxide content of more than 30%. In order to improve the high temperature performance of the brick, generally more than 10% of magnesia is added to the raw material.

Magnesia Chrome Brick
Magnesia Chrome Brick

Chrome bricks are neutral bricks. They have weak effects on acidic and alkaline refractories at high temperatures. Their load softening temperature and thermal shock resistance are lower than those of magnesia chrome brick. Chrome brick is mainly used for the isolation layer of acidic and alkaline refractories at high temperatures, and also for the lining of colored smelting furnaces, but it is not suitable for direct contact with molten iron and where the atmosphere changes frequently.

Chrome Bricks Application

Chromium oxide bricks (referred to as chrome bricks) were first used in non-ferrous metallurgical furnaces and gas slag furnaces, and have excellent corrosion resistance against furnace steel slag, colored smelting slag, coal gasifier slag and various glass liquids. In the past 10 years, this refractory material has been used in glass melting furnaces, but it is limited to dark-bottle glass melting furnaces or alkali-free glass fiber melting furnaces, and is mainly used in high temperature parts of glass melting furnaces. Such as: the upper pool wall, small furnace mouth, fluid hole, feeding port and so on. Because it can significantly extend the kiln age, it has caused widespread concern in the glass industry.

Mag Chrome Bricks

Magnesia-chrome brick is a refractory product containing magnesium oxide (MgO) and chromium oxide (Cr2O3) as the main components, and periclase and spinel are the main mineral components. This type of brick has high refractoriness, high temperature strength, strong resistance to alkaline slag, excellent thermal stability, and certain adaptability to acidic slag. The main raw materials for the manufacture of magnesia chrome bricks are sintered magnesia and chromite. The purity of the magnesia raw material should be as high as possible. The requirements for the chemical composition of the chromite ore are: Cr2O3: 30-45%, CaO: ≤ 1.0-1.5%.

Direct Combination of Magnesia Chrome Brick
Direct Combination of Magnesia Chrome Brick

Magnesia-chrome bricks are mainly used in metallurgical industries, such as the construction of open hearth furnace roofs, electric furnace tops, furnace refining furnaces, and various non-ferrous metal smelting furnaces. The high temperature part of the ultra high power electric furnace wall is cast and cast magnesia chrome brick. The high-erosion zone of the refining furnace outside the furnace is made of magnesia-chrome brick made of synthetic material. In the high-erosion area of the non-ferrous metal flash smelting furnace,magnesia chrome brick made of fused cast magnesia chrome bricks and synthetic materials are used. In addition, magnesia chrome bricks are also used in cement rotary kiln firing zones and glass kiln regenerators.

alumina chrome bricks
alumina chrome bricks

Aluminum chrome brick

Aluminum chrome bricks are based on corundum and chromium trioxide. It has low impurity content, stable high temperature chemical properties, high melting point, high hardness and high strength. Aluminum chromium has good corrosion resistance and thermal shock resistance, but the load softening temperature is lower due to higher impurity content.

Castable Refractory Mortar

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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.

Castable Refractory Mortar
Castable Refractory Mortar

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 Mortar
High Alumina Castable Refractory Mortars

Refractory Mortar Characteristics and Applications

  1. Good plasticity and convenient construction;
  2. Strong bonding strength and strong corrosion resistance;
  3. High refractoriness, up to 1650 ° C ± 50 ° C;
  4. Good resistance to slag invasion;
  5. Good thermal exfoliation.
  6. 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.

RS Castable Refractory Mortar Manufacturer
RS Castable Refractory Mortars Manufacturer

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

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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.

Casting Refractory Cement
Casting Refractory Cement

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

  1. 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.
  2. 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.
  3. 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 Castable
Low Cement Castable

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.

Low Cement Wear Resistant Castable
Low Cement Wear Resistant Castable

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.

Steel Fiber Reinforced High Alumina Castables

KilnRefractory

Steel fiber reinforced refractory castable, is the refractory castable made of refractory aggregate, powder, binder, admixture and steel fiber (heat resistant stainless steel fiber, generally 0.6%~2.5%). It has the characteristics of high strength, wear resistance and thermal shock resistance. Applicable to masonry at high temperatures with mechanical vibration, thermal shock, wear and other parts.

Steel Fiber Reinforced High Alumina Castables
Steel Fiber Reinforced High Alumina Castables

Steel Fiber Reinforced Refractory Castable Application

It is widely used in the steel, metallurgy, chemical and building materials industries in boilers and furnace outlets, tops, side walls, etc.; in CFB boilers, it is often used in furnace outlets and side walls, top, cyclone separators. , cyclone separator top, return feeder and other parts.

Theoretical basis for steel fiber reinforcement

For general refractory materials, they are not wear-resistant during use, have poor seismic resistance, and are prone to cracking and crushing at high temperatures. The addition of steel fiber can greatly improve the strength and the cracking of the structure, thereby achieving the purpose of prolonging the service life of the furnace. The addition of steel fibers to the amorphous refractory material results in a significant improvement in refractory properties.

The main features of steel fiber as a refractory reinforcement

(1) The strength of steel fiber is very high. According to the composite material rule, the toughness, crack resistance and peeling resistance of steel fiber after adding steel fiber increase, which is beneficial to the overall improvement of tensile strength and bending strength of refractory material.

(2) In the steel fiber reinforced refractory material, since the steel fiber is present as a crack arresting expansion, it is intended to prepare a gradual expansion process of the microcrack generated in the refractory material under the action of thermal stress and mechanical stress.

(3) Due to the action of the steel fiber in the refractory material, even in the case of cracking of the refractory material, it can be carried, thereby improving the fracture work of the refractory material and finally increasing the plasticity of the refractory material. The fracture work of the steel fiber refractory is more than several times greater than that of the steel fiber refractory. Therefore, the steel fiber increases the shock resistance and mechanical shock resistance of the refractory material.

Compared with non-reinforced refractory castables, heat-resistant steel fiber reinforced high-aluminum castables have excellent toughness, high strength, good impact resistance and thermal shock resistance. They can be used in key areas to significantly improve the performance of refractory castables. Extend the service life of refractory products.

The use of steel fiber reinforced high-aluminum castables can reduce the number of furnace inspections, save refractory materials, and reduce furnace costs and furnace fuel. At the same time, the operating rate of the kiln was increased, the production time was increased, the output was increased, and obvious economic benefits were obtained.

Website: https://kilnrefractory.com