Heat storage brick for electric heating furnace

Abstract

The utility model discloses a heat storage brick for an electric heating furnace. The heat storage brick comprises a heating brick, a ventilation brick, a corner brick and the like. The heat storage brick comprises a brick body and an inner hole, and the matching end of the brick body is provided with a convex connecting table and a concave connecting groove correspondingly. And the matching outer circle of the convex connecting table and the matching inner circle of the concave connecting groove are matched and positioned. Protrusions are designed on the boss face and the circular ring face of the convex connection platform, grooves are designed in the inner end face and the outer end face of the concave connection groove, the positions and the sizes of the protrusions and the grooves correspond to each other, curved surface sealing is formed in a matched mode, and the effect of isolating furnace gas is achieved. The positions of the protrusions and the grooves can be interchanged, and the protrusions and the grooves can be triangular, semicircular, trapezoidal and rectangular. The electric heating element is placed in the inner hole, the groove and the protrusion are matched and sealed, trace inert gas is introduced to protect the electric heating element, and the service life of the electric heating element is prolonged.

Description

Technical Field

[0001] The utility model is applied to the field of heating furnaces and relates to an electrically heated heating furnace, in particular to a radiation-heated heat storage brick. Background Art

[0002] The electric heating elements of electric heating furnaces include electric furnace wires, resistance strips, silicon carbon rods, molybdenum wires, silicon molybdenum rods, etc. Electric furnace wires and resistance strips mainly include two categories: iron-chromium-aluminum alloy electric furnace wires and nickel-chromium alloy electric furnace wires. The former is an alloy material with ferrite structure, and the latter is an alloy material with austenite structure. From room temperature to high temperature, there is no phase change. The disadvantage is that it is in a hot state under working conditions and is easily oxidized and burned out in the air. Silicon carbon rods are rod-shaped non-metallic high-temperature electric heating elements made of high-quality silicon carbide materials, processed, high-temperature silicified, and recrystallized. Silicon carbon rods have a large specific resistance, with a negative characteristic curve from room temperature to 800℃ and a positive characteristic curve above 800℃. When heated in air, the surface temperature of the heating part can reach 1450℃. At high temperatures, water vapor, hydrogen, halogens, sulfur, etc. also have oxidation and corrosion effects on it. In order to ensure that the furnace temperature and the rod bear the load evenly, resistance matching must be carried out before installation to keep the resistance consistent by ±10%. Silicon molybdenum rod is a kind of resistance heating element. It is brittle and easy to break at room temperature. When heated to a high temperature in an oxidizing atmosphere, a dense quartz glass film is generated on its surface to prevent the product from oxidation. The surface temperature of the heating part can reach 1900°C, and the maximum operating temperature is 1750°C in an oxidizing atmosphere. The resistance of the silicon molybdenum rod does not change with the length of use (resistance increases with increasing temperature), that is, it does not age, so new and old components can be mixed and used. According to the temperature of the electric furnace and the requirements of the atmosphere medium, the heating element can use molybdenum wire or tungsten wire, but it is expensive. In summary, the main factor affecting the service life of the electric heating element is the atmosphere in the furnace. Isolating the adverse effects of the atmosphere in the furnace on the electric heating element is the main purpose of this application.

[0003] CN206300253U provides a self-anchoring heat storage brick, in which the self-anchoring block cooperates with the self-anchoring notch, and the self-positioning block cooperates with the positioning groove, which not only improves the masonry efficiency, but also increases the stability of the masonry. CN207849526U provides a solid heat storage brick with a similar structure, in which the positioning protrusion and the positioning groove engage to achieve self-positioning, shortening the construction time. The staggered seams of the heat storage brick increase the stability of the heat storage body. The above two patents use low-peak electricity to heat the heat storage brick, and release heat during peak electricity consumption to save electricity, and there is no sealing requirement for the ventilation channel.

[0004] CN202166319U provides a new type of refractory brick for introducing steam into a crematorium. The design of a convex platform and a concave groove is used to prevent the heat diffusion of steam. A convex eave is set on the brick side wall of the steam hole to prevent dust and other debris from clogging the steam hole. CN215766482U discloses a kiln refractory brick that can fully exchange heat. It is arranged in a split form of an upper brick shell, a lower brick shell, a first heat storage plate, and a second heat storage plate. It is assembled into a whole through a snap-on assembly and an installation structure. Cold air enters the third and fourth air holes from the first vent and is then discharged from the second vent, which greatly extends the circulation distance, increases the heat storage area, and can achieve full heat exchange. The above two patents both use step-type sealing, and the disadvantage is that only one curved surface seal is used, and the sealing effect is slightly poor.

[0005] CN207962808U discloses an electrically heated heat storage brick structure, in which the ventilation duct and the heating component are arranged at different positions to solve the problem of reduced service life of the heating component due to oxidation. Although this patent solves the problem of air volume of the heating component, the heating component is still heated in oxidizing air.

[0006] After searching, no patent application was found that the heating components are protected by inert gas to avoid oxidation or corrosion by furnace gas so as to increase the service life. Utility Model Content

[0007] The technical problem solved by the utility model is to provide a heat storage brick for an electric heating furnace, place an electric heating element in the heat storage brick, use the heat storage brick to isolate the atmosphere in the furnace, avoid the adverse effect of the atmosphere in the furnace on the electric heating element, and use the heat of the heat storage brick to increase the furnace temperature.

[0008] The technical solution adopted by the utility model is: the types of heat storage bricks for electric heating furnaces include heating bricks, ventilation bricks, corner bricks, etc. The heat storage bricks include a brick body and an inner hole, and the masonry matching end of the brick body is designed with corresponding convex platforms and concave grooves. The matching outer circle of the convex platform and the matching inner circle of the concave groove are matched and positioned. The convex platform surface and the annular surface of the convex platform are designed with protrusions, and the inner end surface and the outer end surface of the concave groove are designed with grooves. The positions and sizes of the protrusions and the grooves correspond to each other, and they cooperate to form a curved surface seal to achieve the effect of isolating the furnace gas.

[0009] The inner hole of the heating brick is a straight through hole, which is convenient for the arrangement of the electric heating element. The inner hole of the corner brick is a vertical through hole, which is used to connect the electric heating element and the conductive sheet. The ventilation brick is a ventilation hole processed on the side of the heating brick. The ventilation hole is a double-step structure. Ceramic filter discs are placed on the steps. Refractory cotton is filled between the ceramic filter discs. The refractory cotton can keep warm and reduce the ventilation pressure and ventilation area of ​​the inert gas, thereby saving the inert gas.

[0010] Preferably, the positions of the protrusions and the grooves are interchangeable, and the shapes of the protrusions and the grooves are triangles, semicircles, trapezoids, or rectangles.

[0011] The beneficial effects of the utility model are as follows: the utility model places an electric heating element in the inner hole of the heat storage brick, and the groove and the protrusion of the matching surface cooperate to form a curved surface seal, which can prevent the infiltration of furnace gas, and at the same time, a trace amount of inert gas can be introduced into the inner hole to ensure that the electric heating element is not oxidized or corroded, greatly improving the service life of the electric heating element. The heat storage brick radiates and heats up the temperature of the heating furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a front view of the heat storage brick of Example 1;

[0013] Figure 2 yes Figure 1 Schematic diagram of the left side;

[0014] Figure 3 This is a schematic diagram of the docking structure of Example 1;

[0015] Figure 4 This is the front view of the heat storage brick of Example 2;

[0016] Figure 5 This is a schematic diagram of the structure of the ventilation brick in Example 3;

[0017] Figure 6 This is a schematic diagram of the corner brick structure of Example 4;

[0018] Figure 7 This is a schematic diagram of a masonry structure of the utility model;

[0019] Figure 8 This is another schematic diagram of the masonry structure of the utility model;

[0020] In the figure: 1-brick body, 2-inner hole, 3-groove, 4-protrusion, 5-inner end surface, 6-outer end surface, 7-matching inner circle, 8-matching outer circle, 9-convex table surface, 10-annular surface, 11-ceramic filter, 12-refractory wool, 13-vent;

[0021] 21 - corner brick, 22 - heating brick, 23 - ventilation brick, 24 - electric heating element, 25 - conductive sheet, 26 - casting material. DETAILED DESCRIPTION

[0022] The types of heat storage bricks of the utility model include heating bricks, ventilation bricks, corner bricks, etc. The heating bricks are used for radiation heating, the ventilation bricks are used to feed inert gas into the cavity of the heat storage bricks, and the corner bricks are generally located at the corners of the furnace wall and are used to connect the electric heating elements and the conductive sheets.

[0023] Example 1: Heating Bricks

[0024] This embodiment is a structural form of a heating brick. Figure 1-3 As shown. The brick body 1 is square, which is convenient for furnace wall masonry. An inner hole 2 is processed in the brick body 1. The inner hole 2 is a straight through hole, which is convenient for the linear arrangement of the electric heating element. The matching end faces at both ends of the brick body 1 are designed with corresponding convex platforms and concave grooves. The end faces of the convex platform are convex platform faces 9 and annular surfaces 10, and the outer cylindrical surface of the convex platform is a matching outer circle 8. The end faces of the concave groove are inner end faces 5 and outer end faces 6, and the inner cylindrical surface of the concave groove is a matching inner circle 7. On the convex platform face 9 and the annular surface 10, triangular protrusions 4 are designed, and on the inner end face 5 and the outer end face 6, triangular grooves 3 are designed. The positions and sizes of the protrusions 4 and the grooves 3 correspond. When two heating bricks are laid, as shown in the attached Figure 3 As shown, after the convex platform is fully coated with refractory mud, the outer circle 8 is inserted into the inner circle 7 for positioning, the protrusion 4 and the groove 3 are matched, and the refractory mud fills the brick joints of the two heating bricks, and the brick joints form multiple curved surface seals. Even if the refractory mud shrinks or cracks after drying, the multiple curved surface seals can block the entry of furnace gas, thereby isolating the cavity inside the brick from the furnace gas.

[0025] Example 2: Heating Bricks

[0026] This embodiment is another structural form of the heating brick. Figure 4 As shown, the difference from Example 1 lies in the shape and position of the protrusion 4 and the groove 3. In Example 1, the shape of the protrusion 4 and the groove 3 is triangular. Since the tip is easily damaged by collision, the shape of the protrusion and the groove is changed to a semicircle and a trapezoid in this embodiment. It can also be designed into other shapes such as a rectangle. In Example 1, the protrusion 4 is designed on the boss surface 9 and the annular surface 10, and the groove 3 is designed on the inner end surface 5 and the outer end surface 6. This embodiment is opposite to Example 1. The groove is designed on the boss surface 9 and the annular surface 10, and the protrusion is designed on the inner end surface 5 and the outer end surface. The masonry of the heating bricks in this embodiment is the same as in Example 1.

[0027] Example 3: Ventilation Brick

[0028] This embodiment is a structural form of aeration brick, see attached Figure 5 As shown. A vent hole 13 is opened on the side of the heating brick. The vent hole 13 is a double-step structure. A ceramic filter 11 is placed on each step. Refractory wool 12 is filled between the two ceramic filter plates 11. The inner ceramic filter plate 11 is fixed by the refractory wool 12. When the vent brick is connected to another heat storage brick, the outer ceramic filter plate 11 is fixed by another heat storage brick. Figure 7 shown.

[0029] The main function of the refractory wool 12 is to insulate, prevent the high-temperature ventilation brick from radiating or convective heat transfer, and also has a ventilation function. The function of the ceramic filter 11 is to fix or stabilize the refractory wool, and it also has a ventilation function. When the electric heating element is powered on for heating, an inert gas is introduced from the vent 13. The inert gas passes through the ceramic filter 11 and the refractory wool 12 and enters the cavity of the heating brick, which isolates the air and furnace gas and prevents the oxidation and corrosion of the electric heating element, thereby increasing the service life of the electric heating element. It can be heated continuously for a long time, which is particularly suitable for continuous production heating furnaces. Another function of the refractory wool is that it can reduce the ventilation area of ​​the inert gas ventilation and save inert gas.

[0030] Example 4: Corner Brick

[0031] This embodiment is a corner brick structure, see attached Figure 6 As shown. The inner hole 2 in the brick body 1 forms a vertical through hole, which is mainly used for the masonry of the furnace wall corner to facilitate the connection between the electric heating element and the conductive sheet. The mutually perpendicular matching end surface structure of the corner brick is the same as the matching surface combination at both ends of the heating brick, which is convenient for matching with other heat storage bricks.

[0032] The heat storage brick of the utility model is formed by pressure, then the inner hole mold is pulled out and sintered at high temperature.

[0033] The utility model masonry structure is as shown in the attached Figure 7 As shown, the electric heating element 24 is placed inside the heating brick 22, and a ventilation brick 23 is installed between the heating bricks 22. The ventilation holes on the side of the ventilation brick 23 are connected to the heating bricks. After the heating brick passes through the furnace wall, as the temperature decreases, it can be sealed and connected to the inert gas pipeline. The inert gas pipeline is connected to the inert gas bag, and the inert gas is provided by the bag. Corner bricks 21 are built at both ends of the heating brick 22. Inside the corner brick 21, the electric heating element is connected to the conductive sheet 25. To prevent heat dissipation, refractory wool is stuffed into the corner brick, and then the castable 26 is injected to seal it to prevent air leakage. Figure 8 Another form of masonry is given, which is similar to the Figure 7 The difference is that the corner brick 21 is replaced by a ventilation brick 23 at the connection of the electric heating element, which is convenient for the installation and replacement of the electric heating element. The end of the ventilation brick 23 is stuffed with refractory cotton to prevent heat dissipation.

[0034] The utility model designs an inner hole in the heat storage brick for placing an electric heating element, and at the same time introduces a trace amount of inert gas into the inner hole to avoid the infiltration of furnace gas, thereby ensuring that the electric heating element works in a non-oxidizing or corrosive atmosphere, greatly improving the service life of the electric heating element, and reducing the frequency and cost of replacing the electric heating element. The electric heating element first heats the heat storage brick, and then the heat storage brick radiates and heats to increase the temperature of the heating furnace. The masonry matching surface of the heat storage brick is designed with grooves and protrusions, and the matching of the grooves and protrusions forms multiple curved surface seals to ensure the sealing effect of the heat storage brick.

Claims

1. A heat storage brick for an electric heating furnace, characterized in that: The types include heating bricks, ventilation bricks, and corner bricks; the heat storage brick comprises a brick body and an inner hole (2); the masonry matching end of the brick body is designed with a corresponding convex platform and a concave groove; the matching outer circle (8) of the convex platform and the matching inner circle (7) of the concave groove are matched for positioning; the convex platform surface (9) and the annular surface (10) of the convex platform are designed with a protrusion (4), and the inner end surface (5) and the outer end surface (6) of the concave groove are designed with a groove (3); the position and size of the protrusion (4) and the groove (3) correspond to each other, and they match to form a curved surface seal.

2. The heat storage brick for an electric heating furnace according to claim 1, characterized in that: The inner hole (2) of the heating brick is a straight through hole.

3. The heat storage brick for an electric heating furnace according to claim 2, characterized in that: The ventilation brick is formed by processing ventilation holes (13) on the side of the heating brick.

4. The heat storage brick for an electric heating furnace according to claim 3, characterized in that: The vent hole (13) is a double-step structure, a ceramic filter (11) is placed on the steps, and refractory cotton (12) is filled between the ceramic filter plates (11).

5. The heat storage brick for an electric heating furnace according to claim 1, characterized in that: The positions of the protrusion (4) and the groove (3) are interchanged.

6. The heat storage brick for electric heating furnace according to claim 1, characterized in that: The shapes of the protrusion (4) and the groove (3) are triangle, semicircle, trapezoid or rectangle.

7. The heat storage brick for an electric heating furnace according to claim 1, characterized in that: The inner hole (2) of the corner brick is a vertical through hole.

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