Quality of a laying of the furnace depends on correctness of preparation of a clay solution, a thickness of seams, bandaging of a brick and its quality.
The Solution for a laying should be average, or normal, plasticity. Such solution gives small usadku, drying up does not burst, strongly connects among themselves bricks and maintains a heat (to 1000°С) without collapsing.
very plastic, or fat, the solution is very convenient in work as it is levelled on a brick by a thin layer without rupture, but, drying up, bursts, gives big usadku, and in an operating time sticks to hands that complicates a laying.
Maloplastichnyj, or lean, the solution does not burst, almost does not give usadki, but unsteadily connects among themselves a brick, and from seams quickly vykroshivaetsja (is showered).
The Clay solution is better to prepare from a brick-raw. In such solution the demanded quantity of clay and sand contains.
Sand for preparation of clay solutions should be small, i.e. Mountain, cleared of vegetation and large particles (gravel). Such sand sift through a fine sieve with cells 1,5x1,5 mm. It is possible to apply a sieve and with larger cells - to 3x3 mm but then in a solution there will be grains of sand krupnostju to 3 mm that will not allow to receive a thin seam.
The Quantity of the sand added in a solution, depends on quality of clay. Experts-stove-makers define quality of clay, pounding it between fingers, but it is reached by the big practice. In house conditions clay can be checked up in the next ways.
the First way. In a bucket (10) with clay add water and mix ostrogannoj a long plate (oar) to smetanoobraznogo conditions (fig. 143). If the solution has covered an oar with a thin layer (1 mm) then he lean, maloplastichnyj and demands addition of fat clay. If the clay layer on an oar has reached 2 mm and it has stuck separate clots clay has normal plasticity. The thick layer of the clay which has stuck to an oar, testifies to its high plasticity and necessity of addition of sand. Sand should be added in the small portions, at first on a bucket an one-litre jar. Further sand in such portions add until the solution will not reach normal plasticity.
the Second way. the clay Cleared of large particles measure in the identical portions, for example an one-litre jar. Select five portions: the first leave in the pure state, in the second add the one tenth part sand banks, in the third - the one fourth part, in the fourth - three fourth, in the fifth - a full jar. This way apply to clay of average fat content. In fat clay sand add in following quantity: in the second portion - 0,5 banks, in the third - a full jar, in the fourth - 1,5 banks, in the fifth - 2 banks. The first portion remains without additives.
Sand carefully mix with clay and in the received mix add water until at hashing the solution which is well kneaded by fingers and not sticking to hands will not turn out. From every portion solution skatyvajut on five balls in diameter to 5 see From two balls every portion do flat cakes in the thickness on 2-3 Balls see and flat cakes dry indoors without draughts 8-12 sut, is better on a floor.
The Solution is considered suitable for a furnace laying if the dried up balls and flat cakes have not cracked, and balls, falling from height of 0,75-1 m, are not scattered on a floor. If on flat cakes along the edges there are small cracks such solution is still admissible to use for work.
Flat cakes and balls from a fat solution rastreskivajutsja along the edges. On balls from lean, it is not formed cracks, but, falling, they are scattered. At small pressing of a flat cake from such solution also are scattered on small slices.
To Check up suitability of a solution it is possible and so. The rolled balls on one put between stroganymi boards and press on top of them. By small pressing the ball from lean clay is scattered on pieces, and it occurs, when compression only begins. On a ball the big cracks are formed of a few more plastic clay at compression for 1/5-1/4 diameters (fig. 144, on a ball from normal clay same under the form, but more thin cracks appear at compression for 1/3 diameters (fig. 144,). At balls from fat clay thin cracks arise at their compression for 1/2 diameters.
From the same clay test, as balls, unroll hands zhgutiki in the thickness of 1-1,5 sm, in the length 15-20 These see zhgutiki check on extension or bending in the form of a ring round round wooden skalki in diameter 4-5 Zhgutiki from fat clay see the sharp ends (fig. 145 are extended smoothly and gradually utonshajutsja, forming in a rupture place. ZHgutiki from normal clay are extended smoothly and break, when the thickness in a rupture place reaches 15-20% of initial diameter (fig. 145,). ZHgutik from lean clay it is a little stretched or nearly so it is not stretched and gives rough rupture (fig. 145,).
At bending around skalki on zhgutike of fat clay it is not formed cracks (fig. 145, on zhgutike from the normal there are small cracks (fig. 145,), and on zhgutike from the lean there are many large cracks and ruptures (fig. 145,).
Having picked up a solution, begin its preparation, measuring clay and sand corresponding volume parts. Before preparation of a solution materials sift through a sieve. Clay to sift difficultly, therefore it is recommended to be measured at first in the necessary quantity, to load in a flank or a box and to fill in with water, carefully having mixed. Razmokshuju clay again well mix, add water before reception of density of liquid sour cream and filter through a sieve, it is better with cells no more 1,5x1,5 mm. In clay add the necessary quantity of sand, and the received mix carefully mix, and then filter through a sieve with cells to 3x3 mm to give to a solution uniformity. Well mixed clay solution easily slips from a steel shovel, without spreading on it. To the touch it is homogeneous, in it there should not be separate sandy or clay clots.
Density of a solution is regulated addition in it by waters and hashing. This operation carry out during a furnace laying, on a workplace. The solution should be, as sour cream of average density. Such solution is easily squeezed out under the influence of weight of the soaked brick or at small pressing it. From the sifted (filtered) clay solution it is possible to receive thin (3-5 mm) seams.
Clay solutions have low durability, therefore in them it is recommended to add table salt (100-250 g on a solution bucket) or cement (3/4. Salt preliminary dissolve in water, and cement shut water to density of sour cream and then carefully mix with a solution. The quantity of the solution going on an oven laying, is great enough. On the average consider that without losses on 100 pieces of a brick at its laying flatwise and a thickness of seams of 5 mm 20 l of a solution (2 ten-litre buckets) are necessary. Taking into account losses 2,5 buckets of a solution are necessary. It is necessary for Russian furnaces of a solution on 15-20% more.
We Will remind that only plastic the necessary density the solution well fills all roughnesses of a brick and seams become dense, strong, gas-tight.