Oven made of brick, despite several centuries of use and development of new technologies, we have not lost their popularity and today, especially in rural areas. Brick oven - heating complicated construction, the inner volume of which consists of several zones, exposed to high temperatures of different ranges. But even in the most heated compartments are very important strength, tightness of the furnace body and the chimney as flue gas leakage in the room threatening the life of the residents poisoning or fire.
Pictures making stone furnace brick is of two types - red and a conventional refractory, stacked on the specified composition solution (depending on the heating zone). Russian, Dutch or Swedish oven - massive structures, and the consumption of materials in their construction significant. In this case, the cost of acquisition of bricks can not be avoided, but you can save on masonry mortar - not buy ready-made heat-resistant mixture, tempted by deceptive cheapness, and to prepare them independently.
Strength and uniformity is controlled by brick producer in the production, so rarely questioned. But the quality of home-made solution - the second most important material in the construction of the furnace depends on the characteristics of components and accuracy of manufacture.
Let us consider the furnace masonry mortars, and what should be a clay furnace brickwork.
Types of clay solutions for stoves and fireplaces
When laying the furnace, depending on the temperature zone arrayed is used several types of solution:
- 1200-1300 0C - clay-fireclay and fireclay cement;
- 1100 0C - clay-sand mixture;
- 450-500 0C - sand-lime;
- 220-250 0C - cement and lime;
- range of atmospheric temperature (furnace foundation) - a cement-sand mixture.
Of these mortars clay or made from chamotte it are part of three mixtures of clay and sand, chamotte, clay, cement-chamotte).
Consider these important components of the furnace mixtures for masonry.
Clay brick components solutions heaters
Clay - sedimentary rock grain structure forming substance of which is kaolinite, consisting of a mixture of silicon oxide (47%), aluminum (39%) and water (14%). The name comes from the Chinese kaolin Kaolin area, where it was first discovered this white clay. In the presence of kaolin clay, iron ions of different valences color of this material may be another - yellow, red, brown, blue, green, but the physical properties it is not enough It reflected. The dry clay is lumpy material from fractions of different sizes, when mixed with water forms plastic mass with good adhesion.
Chamotte - a powder obtained by crushing clay pieces spokshihsya during high temperature firing, and thus lost molecularly bound water. chamotte crumb size fractions after crushing or grinding of 0.2 to 2.5 mm. Sifting fireclay powder allows you to divide the size of the fraction, and then finely ground powder is often called fireclay clay, and large - fireclay sand, but the chemical composition and properties of these materials are identical - the high heat resistance and low water absorption.
The degree of sintering depends on the amount of clay (or) and the duration of exposure to high temperature, which causes a division on chamotte:
- nizkozhzhonny - firing temperature of 600-900 0C, water absorption of 25%;
- vysokozhzhonny - a conventional firing at 1300 0C and water absorption of less than 5%, in osobokachestvennogo - at 1500 0C to obtain a water absorption less than 2%.
Important! Shrinkage solutions using nizkozhzhonnogo chamotte makes up 16%. However, the porosity of such solutions after cure is much lower than in the mixtures with vysokozhzhonnym filler, since the difference in shrinkage nizkozhzhonnogo chamotte and a binder (clay) is very small. Therefore, to obtain low porosity refractory bricks, high compressive strength and fracture nizkozhzhonny used chamotte and for masonry mortars - vysokozhzhonny.
Characteristics clay kiln mixtures
The main characterizing parameter of this material is the greasiness, combining the degree of plasticity, strength, water resistance, and adhesion before and after curing.
In nature, the clay is of three kinds - thin, medium fat and oily, clear boundaries between them are not present.
Material belonging to one of the species is determined by simple mechanical manipulation, the most accurate of which is as follows.
Approximately pound of clay is mixed with water until a homogeneous dough-like consistency, after which the resulting mass is formed from a ball diameter of about 5 cm.
The ball is placed between two pieces of glass that slowly squeezing it by observing the formation of cracks on clay:
- the destruction of the ball at the beginning of compression talks about low-fat - thin clay;
- occurrence of fine cracks after reducing the diameter of the sample to 1/3 of the initial value indicates that the clay normal fat content;
- If cracks appeared only when squeezed to half the diameter of the ball - high fat mass.
The main factor affecting the fat content of the clay is the percentage by weight of sand in it:
- from 15 to 30% - lean;
- from 5 to 15% - average fat content;
- up to 5% - fat.
Manufacturing of clay masonry mortars
One or another type of furnace a mixture of clay, acquired in the shop, prepared according to instructions on the package, questions arise here.
If it decided to use for masonry furnace makeshift solution, the basic conditions on which depends on the quality of mixing two - Component correct preparation and compliance proportions components.
On an example of a clay-sand mortar and consider the preliminary step of mixing rules.
Harvested for natural clay oven must be cleaned of impurities - manually removed all extraneous (remains of plants, stones, debris), and large clumps are broken. The mass was then forced through a metal grid with a cell size of about 3 mm.
This "punching dry" - the procedure is time consuming, so rationally cleaned manually clay pre-soak for 2-3 days in a tin trough - stacked layers of 12-15 cm, their abundant wetting, then cover the entire tab water (approximate ratio of 1 part water to 4 parts clay). After 2 days, mixed thoroughly stirred and feet or rubbed through a sieve of 2-2.5 mm cell.
During soaking preparing sand. Fireclay sand training is required, unless Sift if purchased in bulk. A river sand must sift through a sieve with a mesh size of 1-1.5 mm, and then rinsed in running water capacitance to turbidity disappearance and put on a clean inclined plane to remove as much as possible residual moisture.
Strict volume ratio of these components did not exist, as in any clay originally in any amount present sand. Therefore, the proportion may be from 1: 2 to 1: 5, and ideally should only clay to fill the voids between the grains in the solution.
To have a rough idea of the volumetric ratio of the components in the bucket is filled 1/3 of the clay slurry on its availability, and then fill up on the edge of the sand. The materials are thoroughly mixed in any capacity to the desired consistency with the addition of the required amount of water. Readiness mixture for masonry furnace is checked as follows: - it must be kept on the trowel after its plane of revolution 1800 and slide off it during vertical position.
If the mixture is falling from the inverted 1800 base, then it is necessary to add clay. If the solution does not slide off vertical plane - to bring sand. After adjustment check is repeated.
Testing the solution thus obtained approximate volumetric ratio of the components.
Clay-sand mortar is applied in areas of the furnace having a temperature up to 1000 0FROM. Complete or partial replacement of river sand on chamotte can be used for the mixture with the masonry furnace operating temperatures up to 1800 0With, including in the areas of direct contact with the flame.
Important! Clay solutions without the use of cement allows to disassemble heater brick after curing and assemble it again without destroying the elements.
More clearly answer the question of how to prepare a solution for masonry furnace is given in this video:
conclusion
Availability clay in nature does not mean its primitiveness as a building material - solutions based on this mineral, cooked correctly, served in the stone heaters centuries. Therefore, the use of mixtures based on clay - sign of professionalism stove-maker, and no cause for skepticism.
The main essence of the article
- Stone oven - a complex engineering structure, the effective use of which depends, in particular, and the quality of the materials used for its construction.
- Clay - a natural material available, and today has not lost its demand and surpassing portland cement on a number of characteristics.
- For quality brickwork is necessary not only to choose the right clay for the oven is being built, but it is qualitatively prepare for the introduction of the solution.
- High quality components of the solution for laying the furnace ensures the functionality of the mixture only if the necessary proportions.
- The advantage of clay, among others, is the ability to fully sort out the clutch again without prejudice to the dismantled materials.