RU2406050C2 - Method and device for optimal use of furnace for ceramic tiles - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: method for control and feedback adjustment of tunnel furnace for baking of ceramic tiles, comprising burners arranged over roller bed plane and underneath, nozzles that distributed forcedly supplied cold air in exit part of furnace, and means of temperature measurement in working space of furnace, by means of processor, where the following stages are carried out: processor is adjusted for required temperature curve, information is entered into the first memory of processor about standard defects of shape and size of tiles, changes in furnace control made to eliminate defects are stored in the second memory for each of standard defects, flatness and dimensions of each tile are monitored at certain time intervals in one and the same transverse row of tiles outgoing from furnace to determine type of defect by comparison with data available in the first memory, and message is sent about detected defect into processor, which identifies defect by means of its comparison to data available in the first memory, and changes supply of burners and nozzles with cooling air on the basis of data available in the second memory.

EFFECT: invention makes it possible to develop method and device with feedback for control of tunnel baking surface in compliance with quality of products detected at the exit from furnace.

38 cl, 2 dwg

Description

Technical field

The invention relates to kilns for firing ceramic tiles and, in particular, to controlling the quality of products processed in these kilns.

State of the art

The positive result of firing tiles in kilns, known as tunnel kilns, almost exclusively depends on observing the longitudinal temperature curve maintained in each furnace cross section throughout its volume.

In this context, the term longitudinal temperature curve means a temperature curve in the direction of advancement of the tiles, i.e. in a direction parallel to the axis of the furnace.

The kilns to which this invention relates include a roller conveyor for transporting material located in a tunnel structure having side walls, as well as two sets of burners directed towards the axis of the furnace and located on the side walls along the entire length of the furnace. One set of burners is located above the roller table, the other is below it, each set having alternating burners of the first type, known as radial burners and intended primarily for heating the zone near the side walls, and the second type, known as axial burners, and intended primarily for heating middle zone of the furnace.

In the final part of the furnace, in close proximity to the outlet of the processed material, there is a device for quick cooling of tiles. This device consists of differently oriented nozzles distributing cold compressed air, which is supplied by a compressed air source, for example an axial or radial fan.

All product quality indicators depend on the longitudinal temperature curve, for example, the flatness of the tiles leaving the furnace and the correctness of their dimensions.

In prior art solutions, processes are described that automatically maintain a constant longitudinal temperature curve even when there are interruptions in loading. This ensures that product quality is maintained within commercially acceptable limits.

In known processes, the correction of the temperature curve is carried out in feedback mode by acting on the burners heating the kiln; those. intervention in the heating path of the furnace occurs on the basis of a defect found in the product after it leaves the furnace.

Known processes provide certain results in eliminating deviations in size, however, they turned out to not meet the requirements for deviations in flatness.

It has also been found that known processes have limitations regarding size deviations in the case of an increase in the transverse dimensions of the kiln.

An object of the present invention is to provide a feedback method and apparatus for regulating a tunnel kiln in accordance with product quality determined at the outlet of the kiln.

As mentioned above, with regard to eliminating deviations in size, temperature control in the furnace above and below the roller table provides some positive results, however, such a positive result was not noted with respect to flatness.

This is due to the fact that the tiles, due to their ductility at a high firing temperature, show a tendency to relax on the live table under the influence of their own weight, which leads to their not very high sensitivity to the temperature difference above the plane of the live table and under it.

Tiles show a tendency to shrink, increasing as the firing temperature rises. This shrinkage is due to gas evolution and pore healing during partial sintering, so that controlling the temperature in the furnace cross section gives good results in maintaining tile sizes at a commercially acceptable level even close to the walls of the kiln.

Flatness deviations detected at the furnace exit also occur, moreover, mainly in the rapid cooling zone and can be attributed to different shrinkage of the material in the tile parts located closer to its upper and lower surfaces.

The greater the coefficient of thermal expansion of the material in the above areas, the stronger the reduction in size during cooling.

In this regard, the invention consists in influencing the coefficient of expansion of the material in order to influence the flatness of the tile.

The expansion coefficient of materials having a glassy component, i.e. such as ceramic tile material, increases significantly with decreasing cooling rate.

In accordance with this, the mentioned effect should be implemented through the influence on the cooling rate at the stage of rapid cooling, but this effect should be different for the upper and lower surface of the tile.

This makes it possible to achieve the object of the invention by combining the features listed in independent claim 1 of the invention regarding the method and independent claim 35 of the invention relating to the device.

The dependent claims relate to preferred embodiments of the invention.

Disclosure of invention

In fact, the method according to the invention includes the experimental determination of the optimum longitudinal temperature curve CT _{0 of} firing, depending on the material being processed, as well as on the size and characteristics of each batch of tiles to be fired.

In accordance with the aforementioned curve, at the beginning of the firing operation of the next batch of material, the thermal power units of the kiln are set to a certain heating and cooling mode.

During the entire process of firing the material, the internal space of the furnace is monitored with registration of the following parameters at discrete critical points: temperatures T _IST along the axis of the furnace and at least one of the side walls along a line parallel to the axis, both measurements being carried out on the roller table and under it.

In various sections of the furnace, deviations ΔT of the monitored temperature T _IST from the optimal curve stored in the memory are stored and transmitted to the processor controlling the furnace, which performs the first correction of thermal power units in order to maintain the values within the acceptable range.

With a pre-set interval at the exit of the furnace, the flatness and dimensions of each tile from those in the same outgoing row are controlled.

In particular, two groups of control tools are provided: the first group for flatness control and the second for size control.

The measured data are compared with the standard, stored values typical of each type of product. As a result of the comparison, a deviation from a predetermined range is determined, and a signal about the type of deviation is supplied to the processor. The processor, according to the program laid down in it, then changes the power of the burners and cooling air supply devices, which affects the deviation.

In particular, the processor is at least equipped with:

- the first memory containing the most common standard tile defects, determined statistically;

- a second memory containing firing and cooling temperature adjustments made to reduce defects of any type;

- a program for establishing the relationship of detected defects with defects stored in the first memory, and for quickly issuing commands to the burners and cooling air sources in order to achieve an adequate reduction in the magnitude of the detected defects in accordance with the data contained in the second memory.

The equipment related to the scope of the invention includes all the means necessary for the implementation of actions to adjust the process.

Brief Description of the Drawings

The correlation between the standard defects of the tiles after firing and the changes to be made to the firing curves will become clearer when considering the following examples, illustrated by the accompanying illustrative materials (drawings), given as particular examples.

Figure 1 is a horizontal projection of the plane of the roller table of the furnace with burners and devices for generating cooling air located above the plane of the roller table.

Figure 2 is a horizontal projection of the plane of the roller table of the furnace with burners and devices for generating cooling air located below the plane of the roller table.

Preferred Embodiment

The drawings show the plane of the rolling table (1), along which the tiles move from left to right in the plane of the picture.

Above and below the plane of the roller table are axial burners (2, 20, 3 and 30) of a known type, designed to heat the middle zone of the furnace, and radial burners (4, 40) of a known type, designed to heat zones near the side walls of the furnace.

The burners are oriented towards the side walls of the furnace, and the burners on one wall are staggered relative to the burners on the opposite wall. Axial burners (2) and (20), located near the entrance of the furnace, are designed for pre-heating the tiles, while the tiles are fired using burners (3), (30), (4) and (40).

The rapid cooling of the tiles begins after the burners (4) and (40) as a result of the supply of cold air (room temperature) through nozzles directed towards the plane of the roller table. The nozzles are located on two upper (5) and (6) and two lower (50) and (60) transverse collectors, as well as on two longitudinal collectors (70) parallel to the axis of the furnace and below the plane of the roller table.

It is desirable that each collector be connected to a cooling air source independent of the sources supplying the other collectors.

The burners (2), (20), (3), (30), (4) and (40) are connected individually or in pairs with the central processor P (not shown in the drawing), which controls the operation of the furnace and gives commands to power each from burners with fuel and air for burning fuel.

The cooling air sources for the collectors (5), (50), (6), (60) and (70) are individually connected to the same processor P, which also controls the working pressure of each of them.

Temperature sensors in the furnace (11) and (11a) are located above the plane of the roller table along the axis of the furnace and near the side walls, respectively.

Temperature sensors (110) and (110a) are located below the plane of the roller table along the axis of the furnace and near the side walls, respectively.

The transverse rows of tiles entering the kiln are moved in turn by a conveyor 8, the axis of which is perpendicular to the axis of the kiln. As a result of this, separate rows of tiles 81 are formed.

The first measuring tool (10) is designed to control deviations in flatness and is located above the conveyor (8), and the second measuring tool (9) of a known type is used to control deviations in size and is also located above the conveyor (8). Both tools are connected to the central processor P, where signals are recorded for each deviation (defect).

The standard defects stored in the processor memory and the corresponding remedies are listed below.

A. Large size or small size

This is the case when the dimensions of the product are larger or smaller than required. A defect of this kind is eliminated by increasing or, accordingly, lowering the flame temperature of the burners (3), (30), (4) and (40) by 1-5 ° C on both sides of the plane of the roller table.

An increase in flame temperature leads to a decrease in the size of the product.

B. The effect of trapezoidal lengthening of the side close to the wall of the furnace

This defect is eliminated by increasing the flame temperature of the radial burners (4) and (40) on both sides of the roller conveyor plane.

B. The effect of trapezoidal shortening of the side close to the wall of the furnace

This defect is eliminated by lowering the flame temperature of the burners (4) and (40).

G. Evenly concave shape - upward concavity

This defect is eliminated by exposure in the rapid cooling zone. The cooling air pressure decreases in the collectors (50) and (or) (60) and increases in the collectors (5) and (or) (6). The flame temperature of the burners (30) and (40) located below the plane of the roller table simultaneously increases, while the flame temperature of the burners (3) and (4) located above the plane of the roller table decreases in the zone of the end of firing.

D. Concave shape in planes perpendicular to the plane of the roller table

This defect is eliminated in various ways, depending on the material of the tiles.

In the case of single-fired white and red tiles or glazed ceramic tiles, the flame temperature of the burners (20) and (30), located below the plane of the roller table, decreases in the preheating zone and at the beginning of the firing zone, while the temperature of the burner flame (2) and (3 ) above the plane of the roller table rises. At the same time, at the beginning of the rapid cooling zone, the pressure in the collectors (50) and (or) (60) located below the plane of the roller table decreases, and the pressure in the collectors (5) and (or) (6) above the plane of the roller table increases.

In the case of monoporous or double-fired tiles in the zone of the end of firing, the flame temperature of the burners (3) and (4) above the plane of the roller table decreases, and the flame temperature of the burners (30) and (40) below the plane of the roller table increases by the same amount.

At the same time, the pressure in the lower manifolds (50) and (or) (60) at the beginning of the rapid cooling zone decreases, and the pressure in the upper manifolds (5) and (or) (6) increases.

E. Concave shape in planes parallel to the plane of the roller table

This defect is eliminated by various actions depending on the material of the tiles.

In the case of single-fired white and red tiles, as well as glazed ceramic tiles, the pressure in the lower collectors (50) and (or) (60) decreases, and in the upper collectors (5) and (or) (6) it increases by the same amount.

In the case of monoporous and double-fired tiles in the preheating zone, the flame temperature of the burner (20) decreases (below the plane of the roller table), and the burner (2) located above the plane of the roller table increases by the same amount.

At the same time, at the beginning of the rapid cooling zone, the pressure in the lower manifolds 50 and (or) (60) increases, and in the upper manifolds (5) and (or) (6) it increases by the same amount.

G. Uniformly convex shape - downward concavity

This defect is eliminated by various actions depending on the material.

In the case of single-fired white and red tiles, as well as glazed ceramic tiles at the beginning of the rapid cooling zone, the pressure in the lower collectors (50) and (or) (60) increases, and in the upper collectors (5) and (or) (6) decreases by the same amount.

At the same time, in the firing end zone, the flame temperature of the lower burners (30) and (40) decreases, and the upper burners (3) and (4) increase by the same amount. Further and also at the same time at the beginning of the firing zone, the flame temperature of the burners (30) located below the plane of the roller table rises, and the burners (3) above the plane of the roller table decreases by the same amount.

In the case of monoporous and double-fired tiles, the flame temperature of the burner (3) above the plane of the roller table decreases at the beginning of the firing zone, while for burners (3) and (4) at the end of the firing zone, the flame temperature rises.

Below the roller table, the temperature of the burner flame (30) rises at the beginning of the roller table (at the beginning of the firing zone), and at the end of the roller table (at the end of the firing zone), the flame temperature of the burners (30) and (40) decreases.

At the beginning of the rapid cooling zone, the pressure in the lower manifolds (50) and (or) (60) increases, while in the upper manifolds (5) and (or) (6) it simultaneously decreases.

H. Convex shape in planes perpendicular to the plane of the roller table

To reduce this defect, the flame temperature of the burners (20) and (30) increases in the preheating zone and at the beginning of the firing zone below the plane of the roller table, while the temperature of the burners (2) and (3) above the plane of the roller table decreases.

At the same time, the pressure in the collectors (50) and (or) (60) below the plane of the roller table increases, and the pressure in the collectors (5) and (6) above the plane of the roller table decreases.

I. Convex shape in planes parallel to the plane of the roller table

This defect is eliminated in various ways, depending on the type of material.

In the case of single-fired white and red tiles, as well as glazed ceramic tiles at the beginning of the rapid cooling zone, the pressure in the lower collectors (50) and (or) (60) increases, and in the upper collectors (5) and (or) (6) decreases by the same amount.

In the case of monoporous and double-fired tiles, the flame temperature of the burner (2) above the plane of the roller table in the preheating zone decreases, while for the burner (20) located below the plane of the roller table, the flame temperature rises by the same amount.

At the beginning of the quick cooling zone, the pressure in the lower manifolds (50) and (or) (60) increases, while in the upper manifolds (5) and (or) (6) it simultaneously decreases by the same amount.

K. Convex shape of products located near the walls of the furnace

If the bulge is limited to products near the walls of the furnace at the beginning of the rapid cooling zone, then the pressure in the manifolds (70) decreases.

It is advisable to carry out temperature and pressure adjustments, both upward and downward, in each case in the same doses or in multiples of them, so that after a small number of repeated exposures, the oven goes to the required mode and the tiles being processed are in a commercially acceptable range of quality indicators .

Claims (38)

1. The method of control and regulation through feedback of a tunnel kiln for firing ceramic tiles, including a roller table for moving tiles, rows of burners above the plane of the roller table, rows of burners below the plane of the roller table, rows of manifolds equipped with nozzles distributing the cooling air supplied under pressure in the end part the furnace and located above and below the plane of the roller table, measuring means for measuring the temperature in the working space of the furnace and the processor, which in order to maintain the temperature ry in the furnace according to the required temperature curve controls the supply of fuel and air to the burners, individually or in pairs, and also controls the pressure of the air sent to the collectors, in which the following steps are carried out: adjust the processor to the required temperature curve for each batch of tiles to be fired, place in the first processor memory, information about standard defects in the shape and size of tiles; for each of the standard defects, the necessary changes are specified in the second compressor memory in the direction of increasing silt and lowering the temperature of the flame of the burners and / or the pressure of the cooling air by an amount that should reduce the defectiveness of the tiles, at the exit from the furnace, the flatness and dimensions of each tile of the same transverse row of tiles coming out of the furnace are checked at regular intervals to determine the type of tile detected defect by comparison with the data on standard defects contained in the first memory, transmit a signal of detected defects to the processor, which identifies the defect by comparing with data contained in the first memory and adjusts the power of the burners and / or cooling air nozzles to influence the detected defects on the basis of control signals contained in the second memory and on the basis of the processor program, while the cooling speed is set different for the upper and lower sides tiles. 2. The method according to claim 1, characterized in that the standard deviations in the size of the tiles, which are stored in the first memory, are as follows: calibration size, the trapezoidal lengthening of the side close to the furnace wall, the trapezoidal shortening of the side close to the furnace wall. 3. The method according to claim 1, characterized in that the standard defects in the shape of the tiles that are stored in the first memory are as follows: uniformly concave or convex shape; concavity or convexity in planes parallel to the plane of the roller table; concavity or convexity in planes perpendicular to the plane of the rolling table; convexity of products close to the walls. 4. The method according to claim 1, characterized in that the flatness control of the tiles of each row is performed simultaneously on all tiles in the row. 5. The method according to claim 1, characterized in that the flatness of the tiles of each row is controlled alternately on each tile in the row. 6. The method according to claim 1, characterized in that the size control of the tiles of each row is performed simultaneously on all tiles in the row. 7. The method according to claim 1, characterized in that the size control of the tiles of each row is performed alternately on each tile in the row. 8. The method according to claim 1, characterized in that, in order to eliminate the differences in the size of the template and the workpiece, if the products were larger than required, the second memory contains the following control signals that must be transmitted to the processor: increase the firing temperature by 1- 5 ° C above and below the plane of the roller table. 9. The method according to claim 1, characterized in that, in order to eliminate differences in the size of the template and the workpiece, if the latter turned out to be less than required, the second memory contains the following control signals that must be transmitted to the processor: lower the firing temperature by 1- 5 ° C above and below the plane of the roller table. 10. The method according to claim 1, characterized in that, in order to eliminate deviations in size, expressed in the occurrence of trapezoidal lengthening of the side close to the wall of the furnace, the second memory contains the following control signals that must be transmitted to the processor: increase the temperature of the radial flame burners (4) and (40) in the zone of the end of firing. 11. The method according to claim 1, characterized in that, in order to eliminate deviations in size, expressed in the occurrence of a trapezoidal shortening of the side close to the wall of the furnace, the second memory contains the following control signals that must be transmitted to the processor: lower the flame temperature of the radial burners (4) and (40) in the zone of the end of firing. 12. The method according to claim 1, characterized in that, in order to eliminate flatness deviations in the form of uniform concavity (upward concavity), the second memory contains the following control signals that must be transmitted to the processor: reduce the pressure of the cooling air in the collectors ( 50) and (60) located below the plane of the roller table, and increase the pressure in the collectors (5) and / or (6) located above the plane of the roller table. 13. The method according to p. 12, characterized in that the second memory contains the following additional control signals that must be transmitted to the processor: increase the flame temperature of the lower burners (30) and (40) and lower the flame temperature of the upper burners (3) and ( 4) in the zone of the end of firing. 14. The method according to claim 1, characterized in that, in order to eliminate deviations in flatness in the form of concavity in planes perpendicular to the plane of the rolling table, in the case of once fired red and white tiles, as well as glazed ceramic tiles, the second memory contains the following control signals to be transferred to the processor: lower the flame temperature of the lower burners (20) and (30) in the preheating zone and in the firing start zone and increase the temperature of the burner flame (2) and (3). 15. The method according to 14, characterized in that the second memory contains the following additional control signals that must be transmitted to the processor: reduce the pressure in the lower manifolds (50) and / or (60) in the zone of the onset of rapid cooling and increase the pressure in upper collectors (5) and / or (6). 16. The method according to claim 1, characterized in that, in order to eliminate deviations in flatness in the form of concavity in planes perpendicular to the plane of the rolling table, in the case of monoporous ceramic tiles or double-fired tiles, the second memory contains the following control signals that must be transmitted to the processor: in the firing end zone, lower the flame temperature of the lower burners (30) and (40) and increase the flame temperature of the upper burners (2) and (3) by the same amount. 17. The method according to clause 16, characterized in that the second memory contains the following additional control signals that must be transmitted to the processor: reduce the pressure in the lower manifolds (50) and / (or) (60) and increase the pressure by the same amount in the upper collectors (5) and / or (6) in the zone of the onset of rapid cooling. 18. The method according to claim 1, characterized in that, in order to eliminate deviations in flatness in the form of concavity in planes parallel to the plane of the roller table, in the case of once-fired white and red tiles, as well as glazed ceramic tiles, the second memory contains the following control signals to be transferred to the processor: reduce the pressure in the lower manifolds (50) and / or (60) and increase the pressure in the upper manifolds (5) and / or (6) by the same amount in the area where the rapid cooling starts. 19. The method according to claim 1, characterized in that, in order to eliminate deviations in flatness in the form of concavity in planes parallel to the plane of the roller table, in the case of monoporous ceramic tiles or double-fired tiles, the second memory contains the following control signals that must be transmitted to the processor: lower the flame temperature of the lower burners (20) in the preheating zone and increase the flame temperature of the upper burners (2) by the same amount. 20. The method according to claim 19, characterized in that the second memory contains the following additional control signals that must be transmitted to the processor: reduce the pressure in the lower manifolds (50) and / or (60) and increase the pressure in the upper collectors (5) and / or (6) in the zone of the onset of rapid cooling. 21. The method according to claim 1, characterized in that, in order to eliminate flatness deviations in the form of a uniform bulge (downward concavity) in the case of once-fired white and red tiles and glazed ceramic tiles, the second memory contains the following control signals, which must be transferred to the processor: increase the pressure in the lower manifolds (50) and (60) and lower the pressure in the upper manifolds (5) and / or (6) in the area where the rapid cooling starts. 22. The method according to item 21, wherein the second memory contains the following additional control signals that must be transmitted to the processor: lower the flame temperature of the lower burners (30) and (40) in the firing zones and increase the flame temperature by the same amount upper burners (3) and (4). 23. The method according to p. 22, characterized in that the second memory contains the following additional control signals that must be transmitted to the processor: increase the flame temperature of the lower burners (30) and lower the flame temperature of the upper burners (3) by the same amount. 24. The method according to claim 1, characterized in that, in order to eliminate flatness deviations in the form of a uniform convexity with a downward concavity in the case of monoporous ceramic tiles or double-fired tiles, the second memory contains the following control signals that must be transmitted to the processor : Increase the flame temperature of the lower burners (30) in the firing end zone and lower the flame temperature of the upper burners (3) by the same amount. 25. The method according to paragraph 24, wherein the second memory contains the following additional control signals that must be transmitted to the processor: increase the pressure in the lower manifolds (50) and / or (60) and lower the pressure in the upper collectors (5) and / or (6) in the zone of the onset of rapid cooling. 26. The method according to claim 1, characterized in that, in order to eliminate deviations in flatness in the form of convexity in planes perpendicular to the plane of the roller table, the second memory contains the following control signals that must be transmitted to the processor: increase the flame temperature of the lower burners (20 ) and (30) and lower the flame temperature of the upper burners (2) and (3) by the same amount in the preheating and firing start zones. 27. The method according to p. 26, characterized in that the second memory contains the following additional control signals that must be transmitted to the processor: increase the pressure in the lower manifolds (50) and / (or) (60) and lower the pressure by the same amount in the upper collectors (5) and / or (6) in the zone of the onset of rapid cooling. 28. The method according to claim 1, characterized in that, in order to eliminate deviations in flatness in the form of a convexity in planes perpendicular to the plane of the roller table, in the case of once-fired white and red tiles, as well as glazed ceramic tiles, the second memory contains the following control signals to be transferred to the processor: increase the pressure in the lower manifolds (50) and ((or) (60) and lower the pressure in the upper manifolds (5) and / or (6) by the same amount in the area where the rapid cooling starts. 29. The method according to claim 1, characterized in that, in order to eliminate deviations in flatness in the form of a convexity in planes parallel to the plane of the roller table, in the case of once-fired white and red tiles, as well as glazed ceramic tiles, the second memory contains the following control signals which must be transferred to the processor: increase the pressure in the lower manifolds (50) and / or (60) and lower the pressure in the upper manifolds (5) and / or) (6) by the same amount in the zone where the rapid cooling starts. 30. The method according to claim 1, characterized in that, in order to eliminate flatness deviations in the form of convexity in planes parallel to the plane of the roller table, in the case of monoporous ceramic tiles or double-fired tiles, the second memory contains the following control signals that must be transmitted to the processor: lower the flame temperature of the upper burners (2) in the preheating zone and increase the flame temperature of the lower burners (20) by the same amount. 31. The method according to p. 30, characterized in that the second memory contains the following additional control signals that must be transmitted to the processor: increase the pressure in the lower manifolds (50) and / or (60) and lower the pressure in the upper collectors (5) and / or (6) in the zone of the onset of rapid cooling. 32. The method according to claim 1, characterized in that, in order to eliminate deviations in flatness in the form of convexity of products located near the walls of the furnace, the second memory contains the following control signals that must be transmitted to the processor: increase the pressure in the longitudinal manifold 70. 33. The method according to claim 1, characterized in that the increase or decrease in temperature and pressure is carried out by the same amount under all influences in such a way that as a result of a small number of repeated exposures, the oven reaches the required mode and the processed tiles fit into a commercially acceptable quality standard. 34. The method according to p. 33, characterized in that the increase and decrease in temperature under all influences is carried out by a multiple of one and the same value. 35. A device for regulating by feedback a tunnel kiln for firing ceramic tiles, including a roller table for transporting material, located in a tunnel structure equipped with longitudinal walls, in which there are two sets of burners, one set above and below the plane of the roller table, while the burners are directed to the middle of the kiln and distributed along the length of the furnace, two sets of collectors, respectively, above and below the plane of the roller table, equipped with nozzles for directing cold air towards the rolling table and located in the final zone of the furnace from which the processed products exit, devices for generating compressed air connected to the collectors, means for controlling the temperature distribution along the entire length of the kiln, a processor for controlling the operation of the burners in accordance with the signals supplied by the temperature sensors, characterized in that the device further comprises a first means of controlling the flatness of the tiles exiting the kiln, and a second means of controlling the size of the tiles exiting kiln, while the processor, capable of receiving signals from the first and second control means, contains a first memory that stores standard tile defects in size and flatness, a second memory containing control signals supplied to burners and devices for generating compressed air in order to reduce tile defects for each of the standard defects stored in the memory and a computing unit, which, in accordance with the data received from the first and second measuring means, and data containing In the first and second memory, it controls the operation of individual burners and individual compressed air generators, while the computing unit sets the cooling rate different for the upper and lower sides of the tiles. 36. The device according to clause 35, wherein each collector is equipped with a device for generating cooling air. 37. The device according to p. 35, characterized in that at the outlet of the kiln there is a conveyor, the axis of which is perpendicular to the axis of the furnace, while the tiles leaving the furnace are arranged in a row along the axis of the conveyor, while the first and second measuring devices are located above the conveyor to control the flatness and size of tiles. 38. The device according to p. 35, characterized in that it has temperature sensors located close to the side walls of the kiln.

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