Cases Archives - Global Refractory Brick Supplier & Factory-Rongsheng

How to Choose Refractory Bricks When Building Flues?

2024-09-142024-08-16 by globalrefractory

How to choose refractory bricks when building flues? In addition to weight, the selection of refractory bricks for flues should also be based on the flue gas properties, temperature reduction, and whether it is corrosive. kiln fire bricks. Therefore, lightweight refractory bricks are generally used, such as lightweight mullite bricks, lightweight clay bricks, lightweight silica bricks, etc. They are light in weight and have excellent fire resistance and heat insulation.

Refractory Bricks for Chimney Inner Wall

Refractory bricks are used for chimney inner wall. For round ones, special-shaped bricks, such as axe-shaped bricks or knife-shaped bricks, should be selected, and then some refractory casting materials should be added. For rectangular ones, standard refractory bricks are enough, and it is better to add casting materials.

The lining of chimney refractory bricks can be built with ordinary cement mortar, but it must be heat-resistant. Different industries may also have acid and alkali resistance requirements, and suitable refractory materials should be used.

How often should the acid-resistant bricks of chimneys be replaced? The quality and use conditions of acid-resistant bricks for chimneys produced by different materials and different manufacturers are different. Whether the chimney refractory bricks need to be replaced depends mainly on the degree of corrosion of the lining material of the chimney inner wall.

What are the Refractory Bricks Required for High-Temperature Flue Masonry?

Industrial chimneys are an important part of kilns. They are generally divided into red brick chimneys, concrete chimneys and steel chimneys, etc., and are lined with refractory bricks or refractory castables. kiln fire bricks. The size of industrial chimneys is determined according to the type of kiln and working conditions, and their shapes are mostly cylindrical.

The main function of industrial chimneys is to remove the waste flue gas in the kiln, and it also has the function of preventing the flame from burning in the furnace. When the temperature of the waste flue gas entering the chimney is high, its inner wall is generally built with a working layer. If the flue gas is acidic, acidic refractory bricks must be built, and lightweight refractory castables are also used. Rongsheng Refractory Material Manufacturer can provide high-quality high-temperature flue refractory bricks.

Since the temperature of flue gas is relatively high, the refractory bricks of flue should meet the characteristics of higher refractory bricks. However, some flue gas is corrosive when discharged, so refractory bricks need to be more corrosion-resistant. Therefore, when choosing refractory bricks for flue, in addition to considering the weight of flue, it is also necessary to choose according to the properties of flue gas produced by the medium. Such as the temperature of flue gas, whether it is corrosive, etc., so the refractory bricks of flue are generally based on lightweight refractory bricks. While reducing the weight of flue, it can also resist the scouring and corrosion of flue gas. Therefore, lightweight mullite bricks, lightweight clay bricks and lightweight silica bricks can be selected. In addition to light weight, these refractory bricks also have excellent fire resistance and thermal insulation. Ensure that the flue is not invaded by high-temperature heat flow, and at the same time, it can also resist the continuous scouring and corrosion of flue gas.

Refractory Bricks for High-Temperature Industrial Kilns

When choosing refractory bricks, you also need to make a reasonable choice based on the shape of the chimney, whether to use standard bricks or special-shaped bricks. If the chimney is round, you need to choose special-shaped refractory bricks, such as axe-shaped bricks or knife-shaped bricks. If the chimney is rectangular, standard refractory bricks can be used. kiln fire bricks. When laying bricks, you can choose to use high-temperature glue with the gap between bricks.

At present, the refractory bricks commonly used in chimney construction are: those that can absorb hydrogen fluoride should be alkaline refractory bricks, generally magnesia bricks. If the flue gas is acidic, refractory bricks resistant to acidic media should be selected. There are also common clay bricks, high-alumina bricks and silica bricks. When choosing, you should choose according to the properties of the flue gas.

The flue is the main device for high-temperature kiln exhaust gas emission, and it usually has to withstand the continuous scouring of high-temperature gas. Sometimes some flue gases are also corrosive, so when choosing flue refractory bricks, you usually have to choose bricks that are resistant to scouring and corrosion. At the same time, the bricks themselves also need to have a certain degree of fire resistance. Not only that, in order to reduce the pressure of the flue on the overall kiln and improve the stability of the flue, lightweight refractory bricks should be used as the main material.

Lightweight mullite insulation bricks

Currently, the refractory bricks that meet the above conditions mainly include lightweight mullite bricks, lightweight clay bricks and lightweight silica bricks. These bricks have good fire resistance, scouring resistance and corrosion resistance. Not only that, their weight is lighter than ordinary refractory bricks. Therefore, it is a good choice for building flues at present to ensure that the flue is not invaded by high-temperature heat flow, resist the continuous scouring and corrosion of flue gas, and reduce the overall weight of the chimney. When dealing with ordinary flue gas, we usually focus on lightweight mullite bricks and lightweight clay bricks. When facing gases with certain corrosive flue gas, we mainly focus on lightweight silica bricks because of its good corrosion resistance.

Lightweight clay bricks

When building flues, we need to choose according to the shape of the flue. Generally, for some round flues, special-shaped refractory bricks are mainly used, such as axe-shaped bricks or knife-shaped bricks. When facing some square flues, standard bricks can be used for masonry. When building, refractory mud is mainly used. Kiln fire bricks. It has a certain fire resistance and can ensure that the refractory bricks are closely connected. In the face of some occasions with corrosive flue gas, the refractory mud should also have a certain corrosion resistance.

Lightweight silica bricks

The above is the selection of flue refractory bricks. When choosing flue refractory bricks, in addition to considering the weight of the flue, you should also choose according to the properties of the flue gas produced by the medium. For example, the temperature of the flue gas, whether it is corrosive, etc., these are all things that need attention. kiln fire bricks. Choosing the right refractory bricks can not only improve the stability and thermal efficiency of the chimney, but also ensure the overall stability of the kiln. So pay special attention when choosing.

What are the Index Performances that Need to be Considered When Choosing Refractory for Glass Furnace?

2021-07-01 by globalrefractory

The glass furnace is thermal equipment for melting glass made of refractory materials. When choosing refractory materials for glass kilns, consideration should be given to the type of kiln, the location of use, the mechanism of damage, the types of molten glass, and the types of pigments. Refractories for glass kilns should first be able to resist the erosion of glass melt and gaseous substrates and should have a sufficiently high load softening temperature and thermal stability.

Generally, it is hoped that the refractory materials in various parts of the kiln do not show local premature corrosion, so as to ensure that the entire kiln has a sufficiently long service life. However, due to the different mechanical, physical, and chemical conditions of each part of the glass furnace, the properties of the refractory materials used must be adapted to it. At the same time, it is required not to adversely affect other types of adjacent bricks.

The glass kiln refractory bricks mainly include clay bricks, silica bricks, fused zirconia corundum bricks, fused corundum bricks, magnesia refractories, including magnesia refractories for regenerators. In addition, zirconia bricks have excellent properties such as high-temperature resistance, good thermal shock resistance, and corrosion resistance to molten glass. Alumina-Zirconia-Silica (AZS) fused-cast bricks and fired bricks have good corrosion resistance to molten glass and can be used for the wall and upper structure of glass kilns. Of course, there are also heat-insulating refractory materials for energy saving and heat preservation to save production costs.

What are the index performances that need to be considered when choosing refractories for glass kilns?

When selecting and purchasing refractory for glass furnace, what are the index performances that should be considered first?

(1) Organizational structure

Refractory material is a heterogeneous body composed of solid phases (including crystal and glass phases) and pores. The macroscopic structure of the product is the main factor that affects its high-temperature use properties.

① porosity

In refractory materials, there are often many pores of different sizes and shapes. The open pores (also known as apparent pores) that are in communication with the atmosphere, the interpenetrating pores are called communicating pores, and the ones that are not in communication with the atmosphere are called closed pores. The porosity is usually used to reflect the compactness of the refractory, that is, the percentage of the volume of the pores in the brick to the total volume.

Porosity is the basic technical index of refractory materials, it almost affects the performance of refractory products. The smaller the porosity, the better the corrosion resistance of the refractory and the higher the structural strength. The higher the porosity, the lower the thermal conductivity of the material.

②Bulk density

Bulk density is the mass of refractory material per unit volume (total volume including pores). It directly reflects the compactness of refractory products and is an important indicator to measure the quality of refractory materials and dense refractory products. Generally speaking, the higher the bulk density, the lower the porosity, and the better a series of properties such as strength and high-temperature load softening temperature.

③True density

The true density refers to the ratio of the mass of a porous material to its true volume (without pores). The true volume refers to the volume of the solid material in the porous body. Its value has nothing to do with density and porosity but is related to the chemical mineral composition of refractory materials.

(2) Thermal properties

① Thermal expansion

When the refractory is heated, the property that its volume expands with the increase in temperature is called thermal expansion. It is usually expressed by linear expansion coefficient or volume expansion coefficient.

When using refractory materials, we must pay great attention to their thermal expansion. Expansion joints should be reserved in the furnace structure according to the thermal expansion characteristics of refractory materials. When igniting the kiln, it is necessary to formulate a reasonable heating curve and adopt necessary measures such as adjusting the brace according to the thermal expansion of the refractory material.

② Thermal conductivity

Thermal conductivity represents the size of the thermal conductivity of the refractory material, expressed in terms of thermal conductivity. The so-called thermal conductivity refers to the rate of heat flow through a unit area of a material under a unit temperature gradient. It mainly depends on the chemical composition and organizational structure of the material.

③Heat capacity

Heat capacity, also known as specific heat capacity, refers to the amount of heat required to heat 1 kg of refractory materials to raise the temperature by 1°C under normal pressure. It is of great significance when designing and controlling the heating and heat storage capacity of the furnace.

For more product information and prices of furnace bricks for glass kilns, please contact us. Our Refractory for Glass Furnace and services will not let you down.

Repair Methods and Required Refractory Materials of Converter Lining

2021-05-11 by globalrefractory

Due to the unstable factors of the converter operation, some parts of the furnace lining will be damaged prematurely. At this time, the converter lining needs to be repaired, and the repair should be maintained until the life of the lining is terminated. Repairing the furnace lining is beneficial to balance the damage of the furnace lining, reduce production costs, and extend its service life. In the later period of use of the furnace lining, the number of repairs continued to increase, and the repair time continued to extend. If the stable operation of the converter has been affected, the life of the furnace lining has also come to an end at this time. In the consumption of refractory materials for the entire furnace lining, the reasonable amount of repairing refractory materials is 1/3-1/2. The repair methods of lining refractories can be divided into two types: the “feeding” repair method and the gunning repair method. Next, Rongsheng refractory manufacturers will introduce the two Repair Methods and Required Refractory Materials of Converter Lining.

Refractory Materials for the “Feeding” Repair Method

Put the filling material into the furnace from the furnace mouth, and shake the furnace body. The residual heat in the furnace makes the feeding material have a certain fluidity, and the feeding material is spread on the damaged part of the furnace lining. Refractory materials for the “feeding” repair method shall have the following characteristics:

(1) At the waste heat temperature of the converter lining (800-1200°C), the refractory for refilling should have good spreadability.
(2) The refractory material for the “feeding” repair method should be cured quickly after spreading.
(3) The solidified dosing material has good adhesion to the original furnace lining material.
(4) The feeding material itself should have good corrosion resistance.

The basic raw materials of refractory materials for the “feeding” repair method are magnesia sand and magnesia dolomite sand, and their performance mainly depends on the binder. Commonly used binders are resins, asphalt, and their mixtures. Asphalt is cheap and easy to use, so my country’s iron and steel enterprises favor the use of asphalt-combined refractory materials for the “feeding” repair method.

Refractory for Gunning Repair Method

When the partial part of the converter lining (such as the trunnion) is damaged, the refractory material can be sprayed to the part, and the refractory material and the lining brick can be sintered together, so as to achieve the purpose of repairing the furnace lining. Gunning methods are mainly divided into three types: wet method, semi-dry method and flame method. At present, most domestic and foreign steel companies adopt semi-dry gunning technology.

(1) Wet gunning. The wet gunning refractory is mainly made of magnesia, which is put into the gunning tank, mixed with an appropriate amount of water, and sprayed to the corroded part of the furnace lining, and the thickness of the gunning layer is 20-30mm. This method is easy to use, and it can be used 3 times in one shot.

(2) Semi-dry gunning. The gunning machine used in semi-dry gunning is composed of a storage tank, a compressed air transport mechanism, and a nozzle. The gunning refractory material in the storage tank is fed into the nozzle by compressed air, mixed with 10%-18% moisture, and sprayed on the working surface of the furnace lining at a certain speed under air pressure, and the gunning refractory material is bonded and solidified. The factors that affect the gunning effect include the following two aspects.

①Temperature. Furnace lining gunning is carried out in a hot state, and the residual temperature of the working face significantly affects the gunning effect. The suitable temperature is 800-1000°C.
②The particle composition, binder, water addition and air pressure of gunning refractory materials. The gunning material is magnesia or magnesia dolomite with a particle size of less than 0.1mm. The binding agent is powdered sodium silicate, sodium phosphate, calcium and potassium phosphate and chromate. Adding a bonding agent can increase the adhesion of the gunning material so that it can be effectively attached to the working surface of the furnace lining. At the same time, the binder can form a high-temperature mineral phase at high temperatures. This not only makes the gunning material and the lining working surface firmly sintered together, but also makes it own good corrosion resistance.

The adhesion rate of gunning refractories is generally greater than 85%, and the number of uses is 3-5 times.

Semi-dry gunning is a simple and feasible method to repair converter lining. However, in the gunning process, due to the residual heat, when the added moisture contacts the repaired working surface, a large amount of steam will be generated and a certain vapor pressure will be accumulated, which is not conducive to the bonding of the gunning refractory and the working surface.

(3) Flame method. Flame gunning does not add moisture, but add combustible materials (such as coke powder, coal powder), combustible gases (such as propane, methane, oxygen). Gunning refractory materials burn and generate heat during the injection process, and part of the materials become molten. When they come into contact with the high-temperature working surface, they will quickly melt and sinter together. Flame gunning is usually carried out in the working gap after the converter is tapped. The gunning time is very short, the residual temperature of the furnace lining is high, and the adhesion effect is good. The service life is also longer, generally 10-20 times of use.

Rongsheng refractories manufacturers have rich experience in the production and sales of refractories. We can provide the most suitable refractory materials for the construction and repair of refractory linings of various industrial kilns, as well as the design of refractory materials for refractory linings of various industrial kilns. If you have questions about refractory lining materials for industrial kilns, please contact us. We will provide you with the most suitable solution for kiln production needs.

About Monolithic Refractory

2020-05-27 by globalrefractory

$Monolithic Refractory - Rongsheng Company$

If you are here to find out more about what is monolithic refractory, you have come to the right place. In this article, you’ll discover everything you need to know about the monolithic refractory.

First and foremost, it is important for you to know that monolithic refractory is the general term used for all kinds of unshaped refractory products. In simple terms, monolith refers to big stone. Over the past few decades, these refractories have gained a lot of popularity for various reasons.

One of the biggest reasons for popularity of these types of refractories is that these tend to be cheaper as compared to some of the other types of refractories. The cost of raw material for making this type of refractory is cheaper, and its installation time is less as compared to other types of refractories. Also, far less manpower is required for installing these types of refractories. Also, there is wide availability of skilled people who can install this type of refractory anywhere.

Another reason for the popularity of this type of refractory is that they have a variety of industrial applications through various industries including petrochemical industry, waste disposal industry, cement industry and steel industry among others. These are also available in a variety of forms and formulations. Their relative popularity in various industries comes from their chemical inertness, abrasion resistance, mechanical integrity and thermal shock resistance at high temperatures.

There are many different types of monolithic refractories including castable refractories, ramming refractories, coating refractories and plastic refractories among others. The choice for a particular type of refractory depends on the end user as well as the industry.

If you want to know more about monolithic refractory, there are several resources available online that can help you learn a lot more about this particular product.

Indian Customers Import Refractory From Rongsheng

2019-10-102018-09-10 by globalrefractory

On August 12th, 2018, Indian customer visited our website for the first time. And then, the customer sent us the first inquiry on the 13th, we learned that the customer needs to repair the burning belt on the vertical lime kiln. The advice given by our salesmen is to use magnesia-alumina spinel bricks and magnesia bricks. Through several conversations, customers have a strong interest in our company’s products, and finally decided to come to our company for a field visit.

It’s an honor that Indian customers came to visit our factory from a long way on August 25th. After a visit to the factory equipment and production process, and with the cooperation of our professional team, the customer has established a good trust with our company and signed a contract with us on the second day after visiting the factory. Indian customers are so satisfied with our work that they expressed they are willing to continue to cooperate in the future if possible.

Indian customers also learned about our company’s other products during the visit: silica brick series, acid-resistant brick series and graphite electrodes, and indicated that if there is a need, they will first consider our products!

The Trust of Tajik Customers: Secend Order

2018-09-102018-09-10 by globalrefractory

In the year of 2017, Tajik customers saw Rongsheng products online, and showed interest in our products. And then, they had several conversations with our business staff online. During this period, our sales staff gave a professional introduction to products. Through the understanding of our qualifications and customer cases, Tajik customers immediately placed orders.

On August 19, 2018, our business staff received an email from Tajik customers, saying that they wanted to come to Rongsheng for a field trip to prepare for the next group of projects. Our staff immediately arranged the itinerary for the client. A group of 4 people from the Tajik delegation visited the performance, equipment and production process of Rongsheng in detail and was very satisfied with the results. Through this visit, they have a better understanding of Rongsheng refractories and are more optimistic about our products. It laid a good foundation for the next group of orders. Look forward to more cooperation.

During the visit to the factory, Tajik customers visited the production workshops of a variety of refractory and showed great interest in our various products: high alumina bricks, graphite electrodes, magnesia chrome bricks.

Japanese Customers Visiting to Our Factory

2018-07-26 by globalrefractory

Recently, Zhengzhou Rongsheng refractories usher several Japanese customers to visit our factory. They need products mainly alumina bubble bricks, high alumina bricks, etc., our foreign trade business manager warmly receive them.

To our production base, the customer has a better understanding of the production process, and the need to consult the specific physical and chemical indicators. Japanese customers mainly want our products to be able to fully meet their requirements. Our technical department to the customer to do a detailed answer in terms of technology.

Through the staff to show professional service, sincere attitude and professional interpretation of every detail of the product, get them greatly appreciated.Through this communication, we understand that Japanese customers in the product quality has strict requirements, customers also see the quality of our products.

Finally, the two sides sign a contract. We believe that in the days to come will have more customers choose
Rongsheng, with cooperation and common development.

South Korea GS Companies Import Refractory From Rongsheng

2018-07-26 by globalrefractory

South Korea GS companies need to import refractory products, through the Internet search to see our Zhengzhou Rongsheng Refractories Company, they have a great interest in the refractory bricks on our website, online contact our customer service staff of our foreign trade department and have a pleasant communication, since then, they have raised the problem of lime shaft kiln. Our Rongsheng Refractories Company is also timely and efficient given the corresponding program, they are very satisfied and put forward further cooperation.

Subsequently, the relevant personnel of Korea GS Company come to production base of Rongsheng Refractories, our company put quality control as the most important thing while pushing the production process control and optimizing the organization. Through this visit, they have a better understanding of Rongsheng Refractories, more positive for our products, and sign a long-term supply contracts.

Taiwan Customer Visit our Factory On June 2017

2018-07-262018-06-20 by globalrefractory

On June 2017, our customer from Taiwan have a good journey for visiting our factory for checking our Bricks quality and we have the deep discussion and comnunication each other for some questions about our refractory product, finally, our customer is very satisfied with our product and service and place the first order for our company, and hope we will have more cooperation with us in near future.