How to choose the right brick for masonry stoves

For the construction of heating stoves in individual houses widely used ceramic bricks. The construction industry produces a wide range of brick masonry stove, but what to choose from the proposed items? Before we consider this question, you need to understand the fact that for masonry stoves use two types of bricks is a simple ceramic brick, but with certain characteristics that is used for masonry elements, furnaces, chimneys and refractory or fireclay brick used for masonry hearth furnace.





  What properties should have the bricks used for masonry furnace

Brick kiln needs to meet the following technical requirements:

  • Resistance to high temperatures and exposed to open flame.
  • The ability to store heat and keep it for a long time.
  • Sufficient mechanical strength.
  • Resistance to significant temperature fluctuations.
Solid fuel furnaces built of ceramic brick that meets the requirements of GOST 390-96. This standard entered into force on 1 July 1997 and establishes the technical conditions that must be met for these products in shape and size. Regulatory document defines requirements for the use of products depending on temperature.

Ceramic bricks intended for the construction of thermal units, the requirements are more stringent than for other building materials. In the furnace of the furnaces, the flame temperature may exceed 1000 °C, consequently its walls are subjected to considerable thermal stress. Thermophysical parameters of the material used should be above the specified value.

In the operation of fired heaters is their regular cooling in some cases to negative temperatures. Brick when it is exposed to significant temperature changes in the external environment, which leads to thermal expansion, with subsequent compression. The product must have enough strength to successfully withstand this phenomenon and to avoid the deformation and destruction.

Bricks used for masonry stoves must have a sufficiently high conductivity and the ability to store heat. The first property is required for rapid heating of premises and transfer of energy unburned fuel into the environment. The second quality allows to support the process after the termination of combustion in the furnace for a long time. This allows long enough to maintain a comfortable thermal conditions.

The use of different types of brick masonry elements of different furnaces, Solid fuel furnaces have a fairly complex design, parts which operate in certain conditions. The question arises, what is the need for brick masonry stoves and its elements?

The device of the heating furnace are the following:





1. The firebox and ash pit.

The combustion chamber preferably has a double-layered wall, the inner runs of fire-resistant (refractory) bricks, exterior – facing ceramic bricks. The furnace erected from refractory brick with a maximum fire-retardant properties. Exterior finish furnace working in less stressful conditions and it is possible to use facing bricks, with excellent decorative characteristics.

2. Flues.

Flues are a large heat exchanger and the temperature in them, though lower than in the furnace, but still quite high. For laying of these elements oven used refractory brick. Outside design can be covered with ceramic tiles or facing bricks.

3. Chimney.

The chimney is in direct contact with the atmosphere and experiencing large temperature changes. Therefore, it is used for ceramic bricks with maximum hardiness. Typically, this item also has a two-layer structure with a decorative outer finish of a ceramic brick or a metal box.



The process of a laying of the furnace and an example of using the firebrick to build the heavy-elements and vneshnei of facing ceramic brick.

The use of brick with appropriate characteristics for the device of individual elements of the furnace will provide maximum durability and excellent thermal properties. Experienced potters when selecting material, give the matter special attention. This made a thorough inspection and culling bricks with large cracks and deep damages and splits.

What characteristics should have a ceramic brick masonry kiln and fireclay bricks for masonry fireboxCharacteristics of ceramic bricks for masonry elements of the furnace, flues and trubek we said earlier, the masonry stove is a particular kind of ceramic bricks, now consider what are the main characteristics should have this brick.

Brand density. The first thing to look for when choosing ceramic bricks for furnace is a brand of density. Brand ceramic bricks in density is set in accordance with the requirements of GOST 530-2012. To denote the use of alphanumeric encoding, consisting of the letter "M" and the number from 25 to 1000. Please note that this figure does not indicate the quality of the brick, and only shows its density with pressure. This indicator is important because the more dense the brick is, the more slowly it heats up and therefore cools down slower. The fact that the brick will slowly cool down is nice, because the stove will give off heat longer. But to heat the oven built of brick too dense is harder, especially when it is completely cooled. Here a balance is important, therefore, for masonry stoves use bricks with a density not lower than M-150 and not more than M-250.

Frost. Frost products is defined as the ability to withstand cycles of heating and cooling. This indicator is denoted by a Latin letter F with the addition of the numbers from 25 to 300. The rate of frost resistance of ceramic bricks is important in the construction of external elements of the heating furnace, such as flue pipe. The thing is that this is an integral part of the furnace is in a very hard conditions of constant temperature difference. This has an enormous impact on the brick used for laying pipe. For the construction of such structures it is best to use ceramic brick with frost from F75 to F100.

The thermal conductivity. The thermal conductivity of ceramic bricks will depend on its density and for products used for masonry furnace it must be in the range of 0.59 to 0.72 W/(m×°C).

Full-bodied. Masonry stove is only used solid ceramic brick.



Ceramic brick kiln.

For masonry combustion chamber ovens used refractory brick with the following characteristics
  • Brand products: SHAQ, PB, SA, SB, PV, SWISS and SHUS.
  • Softening temperature not lower than 1300 °C.
  • The uniformity of blocks in the entire volume.
  • High density and low porosity products.
The operating characteristics of the furnace and the duration of its use depends on the quality of the refractory bricks of which built the furnace.

The market of building materials offers a wide range of products that are suitable for masonry fire boxes. The question arises, what is better to lay down a brick oven, so it was durable and retained its properties for a long time. Experts recommend to use a brick, refractory fireclay politicly. These products have the best ratio between the performance cost and thermophysical properties and quality.

Main technical characteristics of ceramic brick, used for construction of solid fuel furnaces, are summarized in the table below:

INDICATORS NORMAL values FOR BRANDS SHAQ SHA SB SWISS SHUS PB PV Resistance, °C 1600 1650 1730 1630 1580 1580 1657 Porosity, % not higher than 23 24 24 24 30 24 25 the tensile strength of product, N/mm2 23 20 - 20 12 20 13 the Temperature of beginning of softening, °C 1320 1300

Fireclay brick.

The choice of the manufacturer of the furnace of the brickMarket of this kind of building materials is extremely rich in the productions of domestic and foreign companies. In this segment is widely represented by products produced by enterprises of Russia, Belarus and the Baltic republics.

 

VITEBSK BRICK FACTORY PLANT # 1.

Ceramic bricks of the manufacturer meet the requirements of the material for furnaces by brand density. Frost products is extremely low. Mark density 180 — 200. Bricks can be used for lining the furnace and flue channels, for other items it the. We can say that this is one of the most common, to date, materials for the construction of the furnace. Use it for laying of the furnace and the first furnace flue is impossible. Need to make the lining of the furnace and the first chimney of refractory fireclay brick.

At a constant direct contact with the fire brick quickly decays. As the products has a low frost resistance, the use of the bricks for the masonry of the outer walls of the flue pipe street, is also excluded. The advantages of this material include the fact that it is one of the budget options and given all the details to use it for a laying of furnaces is possible. Has 2 work surfaces. In General, the quality of the brick can be described as satisfactory.

LODE.

Brick trade mark LODE is in the Baltic States. Ceramic brick has a high density of mark — 500 and frost resistance. The product is used for facing external surfaces of the stove and chimney. Brick this brand has various forms and it is often used to create various decorative elements of the furnace. In its basic purpose, this facing brick.

BOROVICHI BRICK FACTORY.

Products Borovichi brick factory, located in the Novgorod region. Mass production started in 2011, experts estimate its quality as good. Mark-density ceramic bricks M-250, frost indicators at the level of F25. There are significant deviations of products from the measurements of the standards, up to 10 – 12 mm in the same party. This should be considered when masonry stoves and it is best to take a little more brick than you need. Then all depends on the professionalism of the Builder and his ability to select the right product. Brick has rounded upper and lower edges and 3 worktops.

REFRACTORY OR FIRECLAY BRICK MANUFACTURED IN RUSSIA.





Product quality varies greatly, since Frank marriage to quite decent products. Fireclay brick has a smooth color is cream-colored and high density, the right shape with right angles. As we have seen earlier, the brick required for lining the combustion chambers classic stoves, hearths and fireplaces. But the highlight here certain manufacturers quite difficult.

The answer to the question, what is the better brick for furnace usually solves the customer is in agreement with the master. Taking into account several factors, among which the main ones are compliance and cost. On the correct choice of refractory Wichita influencing the performance properties of the construction, savings at the expense of quality is expensive.

Methods of determining the quality of the furnace bricksto check the compliance of the construction materials to requirements of normative documents is carried out according to methods that are approved by a series of Standards. Each of them intended to identify the individual characteristics of refractory bricks:

  • GOST 5402.1-2000. Method of determining residual strain after heating.
  • GOST 4069-69. Method of monitoring the fire resistance of products.
  • GOST 151136-78. Methods of measuring damage to the corners and edges of ceramic blocks.
Research bricks are produced in laboratories using special equipment. At home to check the quality of the refractory brick by the methods described in the standards is impossible. The buyer has to rely on the certificates and qualification of the master, which it is desirable to involve the decision on the choice of material for the construction of the furnace.

Experienced potters are able in many cases to determine the quality of refractory brick according to some criteria. Furnaces are constructed only from solid ceramic bricks with the brand from M150 to M250. In the certificate should be a record that the specified product is designed for this type of work.

To determine the properties of bricks using the following methods:

The vibration and sound. By and large the faces of the brick that held the weight of the applied weak punch with a hammer. The tool needs to rebound from the surface with a crash. This indicates the existence of internal cracks.

Inspection of appearance. Brick must have the correct form with maximum deviation from the standard size in the range of 2 mm to one side or the other.

Internal structure. Is estimated as of the cleavage, the color of the section should be uniform throughout the area. The presence of spots indicates the presence of areas of stress in the array of bricks that can cause its destruction during heating. From the internal structure of the material should not occur spalling of fireclay.

The use of the above methods of assessing the quality of refractory ceramic brick for the construction of the furnace allows to choose the necessary material. The use of building bricks corresponding to requirements of GOST will ensure thermal unit is the appropriate level of strength and reliability. published

 

Source: srbu.ru/stroitelnye-materialy/272-kakoj-kirpich-vybrat-dlya-kladki-pechi.html