WALL SYSTEM FOR A FURNACE, A FURNACE COMPRISING SUCH A WALL SYSTEM AND A METHOD FOR PROVIDING SUCH A WALL SYSTEM

Abstract

The invention relates to a wall system for a furnace, a furnace comprising such a wall system and a method for providing such a wall system.

Claims

1. A wall system (1) for a furnace, which comprises the following features: 1.1 a wall (10), which has 1.1.1 an inner side (11) facing the furnace chamber and 1.1.2 an outer side (12) facing the environment; 1.2 a heat-conducting layer (60), which 1.2.1 is arranged on the inner side (11) of the wall (10); 1.3 bearing surfaces (25), which 1.3.1 are embodied on the inner side (11) of the wall (10); 1.4 refractory bricks (31), which 1.4.1 in each case have an opening (37), which goes through the brick (31), 1.4.2 are arranged next to one another in at least one row (30.1-30.6), 1.4.3 in each case have a side (32), which faces the inner side (11) of the wall (10) and which can be mounted holohedrally to heat-conducting layer, wherein 1.4.4 the openings (37) of the bricks (31), which are in each case arranged next to one another in a row (30.1-30.6), are aligned with one another; 1.5 rods (40.1-40.6), which 1.5.1 are in each case guided through the aligned openings (37) of the bricks (31), which are arranged next to one another in a row (30.1-30.6), and 1.5.2 which in each case bear on a number of the bearing surfaces (25); 1.6 wherein the bricks (31), which are in each case arranged next to one another in a row (30.1-30.6), 1.6.1 can be moved from a first position, in which a clearance is embodied between the bricks (31) and the heat-conducting layer (60), 1.6.2 into a second position, in which the bricks (31) are mounted holohedrally to the heat-conducting layer (60) with their side (32), which faces the inner side (11) of the wall (10), by means of the force of gravity.

2. The wall system according to claim 1 comprising restraining means (50) by means of which the bricks (31) can be restrained in the second position.

3. The wall system according to at least one of the preceding claims wherein the bearing surfaces (25) run inclined downwards towards the inner side (11) of the wall (10).

4. The wall system according to at least one of the preceding claims, in the case of which the bearing surfaces (25) are embodied at different heights.

5. The wall system according to at least one of the preceding claims, in the case of which the bearing surfaces (25) are embodied at different heights, which are spaced apart evenly from one another.

6. The wall system according to at least one of the preceding claims, in the case of which at least two bearing surfaces (25) are embodied at the same height.

7. The wall system according to at least one of the preceding claims, in the case of which the bearing surfaces (25), which are in each case embodied at the same height, are spaced apart evenly from one another.

8. The wall system according to at least one of the preceding claims, in the case of which the bearing surfaces (25) are the bottom side of elongated holes (24).

9. The wall system according to at least one of the preceding claims, in the case of which the side (32) of the refractory bricks (31), which can be mounted holohedrally to the inner side (11) of the wall (10), is embodied so as to be flat.

10. The wall system according to at least one of the preceding claims, in the case of which the refractory bricks (31) are in each case embodied in a cuboidal manner.

11. The wall system according to at least one of the preceding claims, in the case of which the refractory bricks (31) are embodied uniformly.

12. A furnace, which comprises a wall system (1) according to at least one of the preceding claims.

13. The furnace according to claim 12 in the form of a furnace for melting or for treating metal.

14. The furnace according to claim 12 in the form of an electric arc furnace.

15. A method for installing a wall system, comprising the following steps: Providing a wall system (1), according to at least one of claims 1 to 11; positioning the bricks (31) in the first position; moving the bricks (31) in the second position.

Description

[0069] An embodiment of a wall system according to the invention is specified in more detail in the exemplary embodiment below.

[0070] FIG. 1 shows a wall system in a perspective view,

[0071] FIG. 2 shows the wall system according to FIG. 1 in the same illustration as in FIG. 1, but wherein only the first three rows of bricks have been installed completely,

[0072] FIG. 3a shows an area around an elongated hole of a wall system according to FIG. 1 in a lateral view,

[0073] FIG. 3b shows the area according to FIG. 3a, but with indicated alternative positions of the rod in the elongated hole,

[0074] FIG. 4 shows the wall system according to FIG. 1 in a lateral view,

[0075] FIG. 5 shows the wall system according to FIG. 1 in a lateral view according to the sectional line A-A according to FIG. 1, and

[0076] FIG. 6 shows a refractory brick of the wall system according to FIG. 1 in a perspective view.

[0077] Parts, which have the same effect, have partially also been identified with the same reference numerals in the figures.

[0078] The wall system in its totality has been identified with reference numeral 1 in the figures. The wall system 1 is part of a furnace wall.

[0079] The wall system 1 has a steel wall 10 made of steel. The wall 10 has an inner side 11 facing the furnace chamber and an outer side 12 facing the environment. Inside the wall 10 there are provided guide means in the form of channels (not shown) for conveying a cooling agent in the form of water.

[0080] The inner side 11 of the wall 10 is embodied as flat, vertical surface. The wall 10 as a whole substantially has a tabular design comprising an outer edge extending in a rectangular manner.

[0081] The inner side 11 of the wall 10 is coated with a heat-conducting layer 60. The heat-conducting layer 60 is provided as a plastic mortar consisting of 95% by mass of graphite and of 5% by mass of an organic binder. The thickness of the layer 60 is about 1 to 2 mm.

[0082] Four metal plates 20, 21, 22, 23 which are horizontally spaced apart from one another and which are in each case arranged perpendicularly to the inner side 11 of the wall 10 and which extend vertically from the area of the inner side 11 of the wall 10 adjacent to the lower edge 14 of the wall 10 to the area of the inner side 11 of the wall 10 adjacent to the upper edge 15 of the wall 10, are in each case welded to the inner side 11 of the wall 10 as molds.

[0083] On the upper end of the metal plates 20, 21, 22, 23 a horizontally extending metal plate 50 is welded to the metal plates 20, 21, 22, 23. As set forth further below, the metal plate 50 is provided as restraining means by means of which the bricks 31 of the wall system 1 can be restrained in the second position.

[0084] Six elongated holes 24, of which only the respective three uppermost elongated holes 24 can be seen in FIG. 2, are embodied at the same distance from one another on top of one another in the metal plates 20, 21, 22, 23. The elongated holes 24 of the metal plates 20, 21, 22, 23 are in each case embodied uniformly and at the same height. It can be seen in FIG. 2 that four elongated holes 24 are in each case embodied at the same height. The bottom side of the elongated holes 24 in each case forms a bearing surface 25, which in each case runs inclined downwards towards the inner side 11 of the wall 10, according to the course of the elongated holes 24. To better illustrate the wall system 1 in the figures, the bricks 31, which are actually attached to the rods 40.6, 40.5, and part of the bricks 31, which are actually attached to the rod 40.4, are not illustrated in FIG. 2.

[0085] FIG. 3a illustrates an area around any of the elongated holes 24 in a lateral view. The course of the elongated hole 24 inclined downwards towards the inner side 11 of the wall 10 can be seen well, whereby the bottom side of the elongated hole 24 thus also forms a bearing surface, which runs inclined downwards towards the inner side 11 of the wall 10 and which is identified with reference numeral 25. Due to the identical dimensioning of all elongated holes 24, the bearing surfaces 25 of all elongated holes 24 are embodied accordingly.

[0086] An angle of 12° is enclosed between the bearing surfaces 25 and the inner side 11 of the wall 10.

[0087] The wall system 1 has six rows 30.1-30.6, which are arranged on top of one another, consisting of refractory bricks 31, which are in each case arranged next to one another. Each row 30.1-30.6 is in each case formed from sixteen refractory bricks 31, which are arranged next to one another. The refractory bricks 31 in each case consist of a refractory ceramic material on the basis of magnesia (MgO). All refractory bricks 31 are dimensioned generally identically and in each case have a generally cuboidal shape (only the bricks adjacent to the metal plates 20, 21, 22, 23 have notches for a form-fit positioning of the metal plates 20, 21, 22, 23 in the masonry). A refractory brick 31 of the wall system 1 is illustrated in a perspective view diagonally from the top in FIG. 6. According to this, each of the refractory bricks 31 has six flat sides, namely one side 32 (“cold side” of the bricks 31), which faces the inner side 11 of the wall 10 and which can be mounted holohedrally thereto, lateral sides 33, 34, which in each case face the adjacent bricks 31 in the respective row 30.1-30.6, an upper side 35 and a bottom side 36, which in each case faces the bricks 31 of the adjacent row 30.1-30.6, as well as a side 26 (“hot side” of the bricks 31), which faces the furnace chamber. The thickness of the bricks 31, i.e. the length of the bricks 31 from the cold side 32 to the hot side 34, is 300 mm.

[0088] Furthermore, the bricks 31 in each case have a circular cylindrical opening 37, which goes through the brick 31, wherein the bricks 31 in each of the rows 30.1-30.6 are in each case arranged next to one another in such a way that the openings 37 of the bricks 31, which are in each case arranged next to one another in a row 30.1-30.6, are aligned with one another.

[0089] A rod 40.1-40.6 made of steel is in each case guided through the openings 37, which are aligned with one another, of the bricks 31 in each of the rows 30.1-30.6.

[0090] Each of the rods 40.1-40.6 in each case bears on four bearing surfaces 25 simultaneously, which are in each case formed by four elongated holes 24 at the same height. The rods 40.1-40.6 comprising the refractory bricks 31, which are attached thereto, are in each case oriented horizontally through this.

[0091] As can be well seen in FIG. 2, the refractory bricks 31, which are in each case arranged next to one another in a row 30.1-30.6, in each case bear on the bearing surfaces 25 via the rods 40.1-40.6, which are in each case guided through the openings 37 of these refractory bricks 31. Due to the fact that the bearing surfaces 25 of the elongated holes 24 in each case run inclined downwards towards the inner side 11 of the wall 10, these bearing surfaces 25 serve as a rail system, on which the bricks 31 can glide or slide, respectively, diagonally downwards towards the inner side 11 of the wall 10 on these bearing surfaces 25. The bricks 31, which are in each case arranged next to one another in a row 30.1-30.6, can thereby in each case be moved from a first position, in which a clearance is embodied between the bricks 31 and the inner side 11 of the wall 10 (not illustrated in the figures) by means of the force of gravity acting on the bricks 31 and the rods 40.1-40.6, into the second position, which is illustrated in the figures, in which the bricks 31 are mounted holohedrally to the heat-conducting layer 60, attached to the inner side 11 of the wall 10, with their side 32, which faces the inner side 11 of the wall 10.

[0092] To secure the bricks 31 on the rods 40.1-40.6, a disk-shaped head piece 54 is in each case fastened to the respective end of the rods 40.1-40.6.

[0093] The position of the rod 40.5, which is assumed on the bearing surface 25 when the bricks 31 are in the second position illustrated in the figures, is illustrated by means of a circle comprising a continuous line in FIGS. 3a and 3b. The position of the rod 40.5, which is assumed on the bearing surface 25 when the bricks 31 are in the first position, is illustrated by means of a circle comprising a dashed line, indicated with 40.5a in FIG. 3b. An arrow A1 indicates how the rod 40.5 moves on the bearing surface 25, when the bricks 31 move from the first into the second position by means of the force of gravity. The movement of the further rods 40.1-40.4, 40.6 is equivalent thereby.

[0094] As can be seen in FIGS. 3a and 3b, when the bricks 31 are in the second position, the rod 40.5 is resting on the bearing surface 25 with clearance. Accordingly, the rod 40.5 is resting on the bearing surface 25 such that a further movement of the rod 40.5 towards the inner side 11 of the wall 10, indicated by the arrow A2, in a position, indicated with dashed line 40.5b in FIG. 3b, is possible. This allows movement of the bricks 31 due to thermal expansion, even though the bricks 31 are restrained in the second position by the restraining means, i.e. metal plate 50 in the illustrated embodiment.

[0095] In the exemplary embodiment, the wall system 1 is dimensioned in such a way that the refractory bricks 31 as a whole form masonry with dry joints. This is made possible by means of the generally cuboidal shape of the bricks 31, because the refractory bricks 31, which are arranged next to one another in a row 30.1-30.6 are in each case mounted holohedrally to one another with their sides 33, 34, which face one another, and the sides 35, 36 of adjacent rows 30.1-30.6.

[0096] The restraining means, provided as the metal plate 50 being screwed to the upper end of the metal plates 20, 21, 22, 23 is pushed against the uppermost row 30.6 of bricks 31 in said masonry. Accordingly, the uppermost row 30.6 of bricks 31 and, due to said masonry, the rows 30.1-30.5 of bricks 31 below said uppermost row 30.6 in said masonry are restrained in the second position, i.e. in the position in which the bricks holohedrally are in contact to the heat-conducting layer.

[0097] At its four lateral surfaces (left and right lateral surfaces as well as the upper and lower surface), the masonry is covered with a refractory fibrous material 70. For illustrating purposes, fibrous material 70 is only illustrated in parts in FIGS. 1 and 2. The fibrous material 70 acts as an expansion joint between the wall system 1 elements, adjacent to the walls system 1 in a furnace wall.

[0098] The wall system 1 is illustrated in a lateral view in FIG. 4.

[0099] In FIG. 5, the wall system is illustrated in a lateral view according to the sectional line A-A according to FIG. 1. It can be seen well that the side 32 of the bricks 31, which in each case faces the inner side 11 of the wall 10, is in each case mounted holohedrally to the heat-conducting layer 60 at the inner side 11 of the wall 10.

[0100] A method for installing the wall system according to the illustrated embodiment, comprises the following steps:

[0101] Providing the wall system 1 according to the disclosed embodiment (but without the metal plate 50);

[0102] positioning the bricks 31 in the first position;

[0103] moving the bricks 31 into the second position;

[0104] welding the metal plate 50 to the upper end of the metal plates 20, 21, 22, 23.

[0105] In detail, at first a substructure (not illustrated), onto which the lowermost row 30.1 made of refractory bricks 31 is placed in such a way that the openings 37 of the refractory bricks 31 are aligned with one another as well as with the four lowermost elongated holes 24, is initially constructed in the area of the lower edge 14 of the wall 10 so as to produce the wall system 1 illustrated in the exemplary embodiment. A rod 40.1 is subsequently guided through these openings 37 and the elongated holes 24. On the lowermost row 30.1, the brick row 30.2 arranged thereabove is subsequently erected accordingly and subsequently the further rows of the bricks 30.3-30.6 all the way to the uppermost row 30.6.

[0106] For securing purposes, the head pieces 54 are then are fastened to the ends of the rods 40.1-40.6.

[0107] The refractory bricks 31 are subsequently arranged in the first position, wherein a clearance remains between the refractory bricks 31 and the heat-conducting layer 60 at the inner side 11 of the wall 10.

[0108] The substructure is finally removed, so that the refractory bricks 31 move into the second position illustrated in the figures by means of the force of gravity, in which the refractory bricks 31 are mounted holohedrally to the heat-conducting layer 60 arranged at the inner side 11 of the wall 10 with their side 32, which faces the inner side 11 of the wall 10.

[0109] Finally, to restrain the bricks 31 in this second position, the metal plate 50 is pushed against the upper side of the bricks 31 of the uppermost row 30.6 and welded to the upper end of the metal plates 20, 21, 22, 23.

[0110] With said metal plate 50 attached to the wall system 1 as such, the wall system 1 can be moved into any position without losing the holohedral contact between the bricks 31 and the heat-conducting layer 60.

[0111] Further, the refractory fibrous material 70 is attached to the lateral sides of the masonry.