How much does refractory weigh? Refractory brick - technical characteristics, application. Composition and applications of refractories
Description
Chamotte brick ShA-8 (SHB-8) is a molded refractory product used in structures whose operation is associated with high temperatures. The brick is molded from refractory clay with the addition of chemical components, which helps to avoid cracking of the masonry when the temperature changes.
Given the technical characteristics of the material and its durability, it is widely used in the construction of various types of gas boilers, combustion chambers, various furnaces and chimney arches. The correct geometry of the brick, its color and pleasant texture gave rise to the use of the material in private construction.
Storage of bricks is carried out on pallets, in conditions that exclude moisture products. Regulatory documents do not regulate the shelf life of this building material. Before you buy a fireclay brick, you should study its physical and chemical characteristics and standard sizes.
Application
Refractory brick SHA-8 (ShB-8) - designed for laying various thermal units, with a maximum temperature of 1250-1400 C o . Bricklaying is carried out on a special mortar, fireclay mortar and refractory clay.
Characteristics
Name of indicator | Norm for the brand | |
USA | SB | |
1 Mass fraction, %: | ||
Al 2 O 3 not less than | 30 | 28 |
SiO2 | - | - |
2 Fire resistance, °С, not lower | 1690 | 1650 |
3 Additional linear shrinkage or growth, %, no more | - | - |
at temperature, °C | - | - |
4 Open porosity, %, no more, for products of the group: | ||
I | 24 | 24 |
II | 30 | 30 |
5 Compressive strength, N / mm 2, not less, for products of the subgroup: | ||
I | 20 | - |
II | 15 | - |
6 Softening start temperature, °C, not below | 1300 | - |
Chamotte brick is an excellent refractory building material. Its natural base consists of white refractory clay (kaolin), which, thanks to feldspars in its composition, has a fine dispersed structure. Therefore, the use of fireclay bricks is so common in the construction of fuel chambers, chimneys, stoves, fireplaces and other buildings that can often come into contact with flames and temperature changes. After all, such a brick can withstand the temperature of fire in furnaces of 1200 degrees.
Fireclay bricks are used for the construction of stoves and fireplaces, because they can withstand temperatures up to 1200 degrees.
In the industrial production of refractory bricks, powdered kaolin and refractory clay undergo a firing process until their elastic properties are completely lost. Sometimes coarse quartz sand, graphite or coconut powder can be added to the brick. The technology for the production of fireclay bricks must be observed correctly, otherwise, when it is overexposed, the properties will gain even greater strength, but the overexposed brick will become unsuitable for laying chimneys. If it is underbaked, then laying from such a brick will become impossible due to its loose structure.
Types and sizes of fireclay bricks.
During the firing process, kaolin white clay retains its natural white color up to a temperature of 1200 degrees. Above 1300 degrees, it blushes, then, with an increase in temperature, it acquires a brownish tint and a granular basis. This color is considered acquired during production, it will be stable during further use of fireclay bricks.
With the appearance of brown color, the shape of the product may also change. At the exit, it has the correct geometry of the bar, and due to its low weight, it does not significantly affect the load of the foundation.
General properties of fireclay bricks:
- Release according to GOST 390-96, the specific gravity of one brick bar is from 3.4 to 4 kg.
- It has the shape of a rectangle or a wedge-shaped and trapezoidal bar.
- Durable, does not crumble when broken, but only breaks into large pieces.
- The strength is 1700-1900 kg/m.
- Resistant to open fire, able to withstand up to 1500 degrees of surface heating.
- Great for holding and dissipating heat.
Table of properties of fireclay bricks.
Due to its ideal physical qualities, refractory bricks have a high cost. However, its masonry does not always require a huge number of units.
The weight of fireclay products may vary. It depends on the brands of the product. At modern construction enterprises, two grades of refractory bricks are produced: ShA and ShB. The thermal conductivity of the bricks depends on the weight: it will be higher with less weight, and, accordingly, the absorption of moisture and adhesion with the mortar will be better.
When laying chimney buildings using fireclay bricks, the use of an appropriate viscous mortar with a high degree of frost resistance is required.
Therefore, the involvement of professional stove-makers is necessary.
From the author: welcome to our repair and construction site, dear reader. From the article you will find out what size of fireclay bricks is the standard according to GOST. In addition, we will talk about how much fireclay bricks weigh, how fireclay bricks are made, and what properties this building material must have in order for it to perform its functions correctly.
But first, you will find out exactly why you came here - what are the dimensions of fireclay bricks for a stove or fireplace.
Brand and dimensions of products
Refractory bricks are divided into grades. First of all, these are SHA and SB. What are their differences? In short (and we need it), they differ in their production technology. And that is insignificant. The content of the Al203 component in SB is 28%, and in SHA it is 30%. Now there is not much point in delving into these details, we will limit ourselves to what we note: the fire resistance of ShB is 1650 ° C (3002 ° F), and for ShA it is not less than 1690 ° C (3074 ° F). That's probably all we need to know about these notations.
Now - about the sizes. Below in the list - there are several options for the most popular and common types of this building material on the market:
- SHA-8 - 250 × 124 × 60 mm;
- SHA-6 - 230 × 114 × 60 mm;
- SHA-5 - 230 × 114 × 65 mm.
The parameters of the ShA and ShB brands are identical. That is, their sizes are the same.
We also offer you a table of sizes with other varieties. List courtesy of Dimensions Info.
Now you have the necessary information about brands and sizes. And now, as promised in the introduction, we will reveal the topic of the weight of this building material.
Fireclay refractory brick weight
In accordance with GOST, - the specific gravity of one element is 3.4–4 kg. We also give examples of popular brands:
- ShB-8 - 4 kg (250 × 124 × 65);
- ShB-6 - 2.7 kg (230 × 114 × 40);
- ShB-5 - 3.4 kg (230 × 144 × 65).
How is fireclay brick made?
This question is also asked quite often, so in the article we considered it necessary to give a detailed answer to it. In the Russian Empire, refractory bricks began to be used as early as the 17th–18th centuries. The beginning of its use was due to the development of technology and the need to obtain a heat-resistant material that could be used in industry.
Externally, the fire-resistant bricks of the Enlightenment did not differ from those that were used everywhere, but, unlike them, they could withstand temperatures of 1200 ° C and above without damage.
We found such a solution experimentally, but nothing has fundamentally changed in the production technology of this building material since those distant times. It was just that clay was present in its composition, which had passed through the firing procedure. She was the basis of the composition. Its content in the product could be 70% or even more.
Graphite was most often used as a binder (could be replaced by coke powder). But the general standard was adopted only in the 20th century, or rather, in 1927. As a sample, a German-made brick was used, with dimensions of 250 × 120 × 65.
Chamotte, a material used in the production of refractory bricks, is formed by firing clay at high temperatures - 1300–1500°C. This procedure, as a rule, takes place in shaft or rotary production furnaces. In a word, the task of firing is to rid the material of plasticity and to give it subsequent refractoriness.
Chamotte can be conditionally divided into two types - "highly annealed" and "low annealed". Their differences lie in the fact that the first type has a degree of water absorption - up to 10%, and the second - up to 25%.
Fireclay products are used for internal lining of fireplaces, chimneys, stoves. Also, the material has become quite widespread in architecture and even sculpture (second half of the 20th century).
In appearance, it is quite easy to recognize a product made of fireclay. It has a sandy yellow color and a slightly grainy texture. Such material can be used not only in terms of functionalism, but also aesthetics. Let's just say that in appearance, brickwork made of refractory elements looks quite presentable. These bricks not only perform their direct function - the accumulation, preservation and release of heat without damage to themselves and deformations, but also give the fireplace an attractive authentic look. In general, to put it simply, it is not only functional, but also quite beautiful. Let's just say that the masonry will fit perfectly into the design of a cozy interior.
What properties should refractory bricks have? First of all, it is resistance to high temperatures, which is quite logical. Without prejudice to itself, the material must be able to withstand a lot of heating and cooling. It must also have a low thermal conductivity in order to retain heat inside the stove and/or fireplace. In addition, the material must have a large thermal inertia so that it can slowly release heat to the environment, as well as a large heat capacity - in order to be able to accumulate a large amount of heat.
Laying fireclay bricks
There are no special restrictions on its use. The main thing is that it should not be used in rooms with high humidity - more than 80%. To make masonry, the skills that you could get when working with ordinary bricks are enough. But the process of preparing the solution is somewhat specific.
It is necessary to soak refractory clay in water for up to three days. Water should completely cover the material, while it should be stirred at least once every ten hours.
After this procedure, the clay must be passed through a sieve with a mesh diameter of 3 × 3 mm. Then you need to mix the sand, which also went through the screening procedure. The proportions of clay and sand should ideally be as follows: 1:2, that is, one part clay to two parts sand.
These two components should be thoroughly mixed, after which - add water, while constantly mixing the composition. Water is added until the composition is similar to thick mayonnaise in consistency. To increase strength, it is desirable to add salt - 150 g per bucket (10 l), cement (no more than one trowel) of a grade of at least 150. You can also mix liquid glass in an amount of no more than 3% of the total mass.
The laying process does not imply anything specific. Just bricks are laid on the mortar in the dressing. At the same time, during the construction of masonry, it is necessary to control its evenness. First, the bricks must be moistened. Then - apply the solution in a thin layer, as if priming the surface. This is necessary so that the solution penetrates the structure of the refractory brick. Moreover, the solution should be applied both to the brick that will be laid and to the place where it will be placed. And after this “priming”, - you need to apply the main layer of the mortar - and, finally, lay the brick and tap it with a hammer from above, so much so that excess bonding mortar comes out of the gap. After completion of work, the masonry should be wiped with a damp cloth to clean it from contamination with the solution.
Depending on the temperature regime, four categories of seams can be distinguished. They differ from each other, of course, in thickness:
- Not more than 1 mm.
- 2 mm.
- 3 mm.
- 4 mm or more.
The higher the temperature, the thinner the seam should be. As the saying goes, it is better to see once than to hear/read a hundred times. Therefore, below is a video on the topic "How to lay refractory bricks with your own hands":
How much does fireclay brick cost? The average price can vary from 20 ₽ to 40 ₽ or 5–20 ₴. In any case, such prices were in 2017. But if you want, you can find cheaper or more expensive. When purchasing a batch, take into account the fact that truly high-quality products cannot be too cheap. And, as a rule, this building material does not require so much to significantly save. Therefore, do not buy suspiciously cheap building materials. And this applies not only to bricks, but also to other building materials.
logical conclusion
From the article, you learned what dimensions and weight fireclay bricks have, and we also found out some of the nuances of its production, scope and characteristics that a fireclay product should have. Thank you for reading the article to the end, dear reader. I hope it has been useful to you.
P.S. Below is a video from which you will get an idea of how to glue fireclay bricks:
The presence on sale of a large assortment of heating equipment does not reduce attachments to well-made, familiar to all stoves. The ability to fold the stove used to be passed from mouth to mouth.
Now there are more opportunities for learning. In addition to masonry, the master must know how to choose and use the right material.
Not everyone is suitable for the construction of the furnace, but only refractory bricks, which have special characteristics. A mistake, inattention when buying can bring all the work down the drain.
Production
For the production of many building materials with refractory characteristics, clay is used - an inorganic fossil from sedimentary rocks. Clay raw materials are diverse. It is a mixture:
- salts of silicic acid (silicates);
- oxides of silicon, aluminum;
- water from underground sources.
Sedimentary rocks contain admixtures of colored components inherent in each locality.
In the production of refractories, raw materials are necessarily fired at high temperatures. As a result, all moisture evaporates, the mineral components are sintered. The product loses plasticity, turns into a particularly dense stone with refractory characteristics.
The subsequent stages of the technological process include grinding raw materials; introduction of additives: graphite, coarse coke or quartz powders; adding small amounts of water (no more than 10%) to the stage of formation of the required consistency.
The resulting mass is immersed in the hopper, from which it enters the dispenser. A brick made from a portion of the mineral mass is pressed and fired.
The presented technological scheme is widespread and well developed. All characteristics, including the weight of refractory bricks obtained by this method, are stable and meet the requirements of GOST.
Properties
Refractory properties are: ordinary (1580 - 1770 ℃), high (1700 - 2000 ℃), higher (more than 2000 ℃).
According to the volume fraction of cavities, products are divided into several groups:
- especially dense products have a porosity of less than 3%;
- high density - 3 - 10%;
- dense - 10 - 20%;
- ordinary - 20 - 30%;
- lightweight and heat-insulating - 45 - 85%.
According to the type of raw materials and characteristics, features of the application, heat-resistant bricks are usually divided into several types.
The main (basic) refractory brick contains calcium and magnesium carbonates, it is used for finishing steelmaking furnaces. It has the highest strength and thermal conductivity compared to other refractories.
The characteristics create ideal conditions for the smelting of Bessemer steel. There are other types of refractory bricks with specific characteristics.
Types of refractories
Carbon bricks differ in composition from other refractory products. It is based on graphite or coke, the content of which approaches 92%. Carbon brick products have a narrow purpose. Blast furnaces are made from it.
Quartz brick is made from a mixture of quartz and sandstone. The main advantage is the high density. From quartz products, reliable chimneys, fireplace walls, and some types of stoves are obtained.
The material is chemically unstable; can react with acidic, alkaline substances; metal oxides.
Dinas refractory brick is 94% silicon oxide, retains strength well at high temperatures up to 1690℃. The material, in accordance with the characteristics, is ideal for open-hearth furnaces, regenerators.
Semi-acid brick refers to fireclay. Its composition is represented mainly by oxides of aluminum and silicon. The material can be heated in an oven up to 1670℃. It tolerates mechanical loads well; has a large number of pores (up to 30%), less density than other refractories.
Products with a predominant (62%) content of aluminum oxide are called mullite. If the mass fraction of aluminum oxide (alumina) exceeds 90%, then the products are called corundum.
High-alumina bricks are used for laying linings in the construction of metallurgical enterprises.
Alumina brick, which is often referred to simply as fireclay, has found the widest scope. It contains a large concentration of clay (chamotte), able to withstand temperatures up to 1400 ℃.
It tolerates temperature extremes, is inert to the action of alkaline components. Alumina fireclay products are used everywhere in everyday life and industry, due to their good performance.
Fireclay products
Special clay raw materials necessary for the production of fireclay bricks are mined by open methods. Development does not require large financial investments.
Energy costs for the manufacture of products are moderate, which is facilitated by well-established technology.
As a result, fireclay bricks have a price that is quite affordable for the main part of the population. It is this type of refractory products that is most often used for laying furnaces in private housing construction.
The technology is implemented with some features. Therefore, the products have a wide range of density values. Average values vary from 1700 kg/m 3 to 1900 kg/m 3 . There are products with a minimum density of 300 kg/m3 and a maximum of 2100 kg/m3.
Ordinary chamotte refractory bricks withstand temperatures from +1250℃ to +1690℃. There is a chamotte refractory brick that has a maximum temperature of 1800℃. Such products are used in industrial facilities.
The material can withstand from 15 to 50 freezing cycles without change. The average porosity in the group is 8%. The thermal conductivity is 0.62 W/m℃.
The ability to absorb water in refractory fireclay bricks depends to a large extent on porosity. This characteristic in light varieties leaves much to be desired, reaching a value of 25%. Materials with a high density, a minimum content of pores, can absorb moisture in an amount not exceeding 7%.
Typical dimensions and weight
Each size of a single refractory brick has its own index. This is stipulated in the state standard. In total, there are 11 sizes for single products.
If the marking indicates series from 1 to 6a, then the length will be minimal (from 230 mm). For representatives of the 10th series, the length is 345 mm.
The width of the refractory brick varies from 65 mm to a maximum of 160 mm. The usual height falls within the range from 40 mm to a maximum of 75 mm. There is a special type (third) of refractory products with a height of 100 mm.
An important characteristic of a brick is its weight. Due to the variety of refractory brick products, this figure varies greatly. For example, you can take a class 10 unit with dimensions of 34.5 × 15 × 7.5. The weight of such a refractory brick is 7.8 kg.
Due to the great demand and diverse areas of application, the production of bricks with other shapes and sizes has been established: one-and-a-half, three-quarter, trapezoidal, wedge-shaped products. The designations contain mandatory information about the batch parameters.
Due to the fact that fireclay refractory bricks have high strength characteristics, it is extremely difficult to cut them.
Manufacturers, taking into account the needs, produce bricks, which would be more correctly called decorative stones, of various shapes. This kind of product is designed for laying out rounded shapes inside fireplaces and stoves.
In the construction of stone structures operating under the influence of high temperatures, refractory bricks are used. Special additives are introduced into the composition of products in order to prevent the appearance of cracks during strong heating. For the construction of industrial installations using combustion energy, chimneys and fireplaces, refractory bricks of various classes and sizes are required.
Refractory brick dimensions
Depending on the type of additive, firing method and purpose with refractory properties, products are divided into 4 classes:
- quartz (from sandstone or quartz);
- fireclay or alumina (clay products with the addition of fireclay);
- basic (differs in lime-magnesian composition);
- carbonaceous (from pressed graphite or coke).
The last two types are used in industrial enterprises. They withstand significant temperatures. For home stoves, baths and saunas, a fireclay sample is usually taken. Quartz brick withstands temperature well, but is destroyed by acids and other chemical factors.
ShB-5
Outwardly, it looks like a rectangle of golden color.
It has dimensions of 230x114x65 mm. The volume of this brand of brick is 1704 m 3. According to GOST, the product must comply with the following parameters:
- share of aluminum oxide - 28%;
- fire resistance - not lower than 1 650 °C;
- the temperature at which softening begins is absent.
The weight of one piece of such a product is 3.5 kg. Price - from 35 rubles.
SHA-8
The product is used in industrial and private construction. It has a high content of aluminum oxide and is fire resistant. Used for internal masonry (lining) of furnaces and chimneys. Product Feature:
Weight 4.0 kg. Dimensions - 250x124x65mm. Price - from 32 rubles apiece. The cost may differ from the indicated, it depends on the manufacturer and the volume of purchase.
You can learn more about red solid brick and its price per piece from this
ShA-6 (narrow)
Suitable for the construction of heating units with temperatures up to 1,690 °C. The main characteristics of the product do not differ from the ShA-8 brand. The difference is in size. The mass of one product is 3.4 kg. Dimensions - 230x114x40 mm. Price - from 30 rubles apiece.
SHA-5
The dimensions of a unit of goods are 230x114x65 mm. On a pallet of such bricks, 385 pieces are placed. Unit weight - 3.4 kg. The cost of refractory of this brand is from 30 rubles apiece. The laying of this and other types of bricks is carried out on a special refractory mixture.
Size is an important criterion for choosing a building material. The quality of the masonry, durability, practicality and safety of the finished structure depend on the accuracy of the fit. Loose fit of bricks should not be allowed, and areas with a too thin layer of mortar should also be avoided. The calculation of the consumption of refractory bricks is carried out according to the masonry scheme using construction drawings. It is also useful to read about what else is.