RU2459170C2 - Wall of drying chamber, burning chamber or chamber of tunnel furnace for manufacture of structural elements from ceramic or similar material, and wall module for such wall - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: wall module (3a) for wall (3) of drying chamber, burning chamber or chamber of tunnel furnace for manufacture of structural elements (16) from ceramic material contains many layers the most internal one of which is made from heat-resistant material, base (13) in its lower area, and on one or both longitudinal ends there provided is projection (7a) converging in horizontal plane, or on one or on both longitudinal ends there provided is cavity (7b) for receiving projection (7a). The layer forming projection (7a) or cavity (7b) is located with an offset.

EFFECT: quick and simple manufacturing of the structure of the proposed module for wall, which is to be manufactured or removed.

14 cl, 4 dwg

Description

The invention relates to the wall of a drying chamber, a firing chamber, or a tunnel kiln chamber for the manufacture of structural elements from ceramic or similar material, and to a wall module for such a chamber wall according to the preamble of paragraph 1 or 3 of the claims.

In the case of manufactured structural elements, we are talking about a product of mass production, which during its manufacture by drying or firing using a transport device in large quantities is sent to a drying chamber, firing chamber or tunnel kiln chamber. Moreover, to ensure rational manufacture, the drying chamber, the firing chamber, or the tunnel kiln chamber have a relatively large length, which is why high demands are placed on its design, in particular when it comes to the calcining chamber or the tunnel kiln chamber, in which the elements are processed and fired with significant heating, i.e. glow.

However, the above specific requirements are determined not only by different firing temperatures, but also by large mechanical costs, due to already a considerable length, as well as the time required to assemble or disassemble the drying chamber, the firing chamber or the tunnel kiln chamber.

In addition, in particular, due to the relatively large length of this chamber wall, it is necessary to reckon with the stresses of the material, which, if special measures are not taken to prevent these stresses from breaking and cracking as a result of internal stresses.

The basis of the invention is the creation of such a chamber wall or such a wall module according to the restrictive part of paragraph 1 or paragraph 3 of the claims so that they can be easily and quickly manufactured and dismantled at optimal cost.

This problem is solved using the characteristics of paragraphs 1 and 3 of the claims. Preferred improved embodiments of the invention are described in the dependent claims.

The wall of the chamber according to the invention consists of wall modules installed successively in its longitudinal direction, which, with their longitudinal edges facing each other, are connected to the side overlap, respectively, by means of a protrusion extending into the recess.

The wall module according to the invention for the aforementioned chamber wall in one of the embodiments from one or both longitudinal ends, respectively, has a horizontal tapering protrusion. According to another embodiment of the invention, the wall module from one or both longitudinal ends, respectively, has a recess for receiving the protrusion of an adjacent wall module.

For the embodiments according to the invention, it is common, first of all, that the wall of the chamber consists of wall modules installed in series in its longitudinal direction. This ensures that many benefits are achieved.

On the one hand, a significant advantage is that the chamber wall can be made of parts, namely in the form of wall modules, in advance, for example, in reserve, and it is enough to only assemble it at the construction site, which greatly reduces the construction time. Installation, namely the assembly of the modules with each other, in comparison with the usual manufacture of the chamber wall at the construction site, is carried out in a much shorter time. At the same time, the construction itself is much simpler, since the wall modules of the chamber wall can only be installed one after another at an arbitrary length, which is much simpler and faster than continuous production.

Thus, the embodiments according to the invention provide not only acceleration of construction, i.e. reduction of construction time, but also the fact that pre-fabrication, on the one hand, can be carried out far from the construction site, and on the other, before the start of construction.

Another advantage of the embodiment according to the invention is that the wall of the chamber at predetermined intervals along the length has predetermined seams. Due to this, the stresses leading to breaks are limited in their action, respectively, by the length of the wall modules. As a result of this, the harmful effects of stresses are also significantly reduced, and the joints between the wall modules act as joints that compensate for stresses in which stresses cannot propagate. Thanks to this embodiment according to the invention, the chamber wall acquires a certain flexibility, and stresses, mainly, can act only in the region of wall modules, and stress compensation occurs in the region of seams between the wall modules.

Therefore, this embodiment according to the invention is suitable, in particular, for the wall of the firing chamber or the chamber of the tunnel furnace, in which the processing of structural elements occurs at relatively high temperatures and therefore the above-described harmful effects of stresses are especially great.

Since in this embodiment according to the invention the wall modules can only be mounted to each other, and the mechanical connection between the wall modules can be absent, not only installation can be simple and economical, but also simple and destructive dismantling is possible, since for this the wall modules can be removed from friend. Lateral overlap in the area of butt joints according to the invention does not prevent this.

The invention leads to an overlap of the longitudinal ends of the wall modules in the transverse direction of the chamber wall, so that there is not only mutual lateral support, but also overlap of the seam or barrier in the seam, thereby improving thermal insulation and gas impermeability of the seam and chamber wall. For these reasons, it is also preferable to calculate the height of the protrusion and the recess so that they extend at least in the upper region of the chamber wall or corresponding wall module, thereby improving the aforementioned support and seal.

It is known that on the inner side of the chamber wall it is possible to provide a barrier formed by a horizontal rib spaced inward or a labyrinth formed by it, and the rib is located approximately at the height of the transport device for the machined structural elements and almost reaches the transport device, so that the space above the rib is clearly separated from the space below the transverse rib. Due to this, the thermal effect on the region above the rib can be limited, and in the region below the rib it is possible to create the lowest possible temperatures, and therefore operation can be energy-saving and economical. With such a chamber wall, the simplification lies in the fact that a stud connection is provided only in the region above the rib, and it can extend in height through the entire region above the rib.

In the case of the above-described embodiment of the wall of the chamber or wall module with a rib on the inner side, it is also preferable to create a region of the wall of the chamber or wall modules located below the rib from a fluid, and then hardening material, in particular concrete. Thus, manufacturing is simplified, and the strength of the wall of the chamber or wall module is increased, and sufficient thermal insulation is provided, in particular, taking into account the fact that a lower temperature acts below the rib.

Other dependent clauses contain features that improve thermal insulation in the seams and inside the insulation of the chamber wall or wall modules, increase their strength and, in addition, simplify installation and dismantling, which also helps to reduce production costs.

Below the invention is explained in more detail with reference to at least partially simplified drawings and exemplary embodiments, in which:

figure 1 depicts a front view or cross section of a drying chamber, firing chamber or chamber of a tunnel kiln according to the invention;

figure 2 is a vertical section of the wall of the chamber of the drying chamber, firing chamber, or chamber of the tunnel kiln, or wall module of such a chamber wall;

figure 3 - internal view of the wall module;

figure 4 is a horizontal section along the line IV-IV in figure 3;

5 is a horizontal section along the line V-V in figure 3.

For reasons of simplification of the description, the drying chamber, the firing chamber, or the tunnel kiln chamber shown in FIG. 1 are designated as the working chamber 1. Their cavity 2 is bounded by two side walls 3 of the chamber, the ceiling 4 of the chamber and the floor 5 of the chamber, and these elements are elongated and therefore, they also form an elongated or tunnel-shaped working chamber 1.

Opposite side walls 3 of the chamber, for example, are equal to or made and mounted mirror-like. Therefore, in the following only the left wall 3 of the camera in FIG. 1 is described in detail. Its length is denoted by L, height by H, and thickness by D.

The wall 3 of the chamber consists of wall modules 3a, sequentially installed in its longitudinal direction and connected to each other by their front and rear ends, the front and rear narrow end surfaces 6a, 6b abut against each other and form a dividing seam 6, extending along the entire height H wall module 3A.

The adjacent wall modules 3a are each engaged by means of an end connection 7 with a lateral, namely front overlap, consisting of a protrusion 7a protruding from the end surface 6a and a recess 7b made in the opposite end surface 6b, into which the protrusion 7a enters. The result is a connection 7 of two adjacent modules 3a with an overlap of the front and rear sides, providing transverse mutual support and overlapping separation, i.e. butt, seam 6 wall modules 3A.

Another advantage of the overlap joint 7 is that it forms a barrier that reduces the permeability of the dividing joint 6, in particular with respect to gas and heat, and therefore improves the thermal insulation of the chamber wall 3.

In the horizontal width section, i.e. in the region of thickness D, two or more overlapping joints 7 can be located next to each other with lateral displacement.

For thermal insulation, one (or several) longitudinal wall elements or layers of the wall module 3a can (or can) be provided. In an exemplary embodiment, the wall module 3a is formed by several wall elements 3b, 3c, 3d, 3e, 3f extending in the longitudinal direction and along the entire length and / or height of the wall module or only in part and preferably in the form of prefabricated plates.

In an exemplary embodiment, the wall modules 3a comprise the innermost element 3b made of a heat-resistant material, preferably a heat-resistant material, which can withstand temperatures up to about 1050 or up to 1200 ° C, for example, fireclay or refractory concrete. This heat resistant material is preferably also acid resistant.

The outer side of the outer wall element 3c of the wall module 3a forms the front side, and it can be formed, for example, by facing.

The outermost wall element 3c is preferably stabilized by a frame 8 surrounding the wall element 3c from its narrow vertical sides and, preferably, also from the upper side. The frame 8 can be made, for example, of an angular or channel profile, one or both shelves of which overlap the wall element 3c in width. At least between the shelves or shoulders of rolled profiles extending on the narrow sides of the wall element 3c and the wall element 3c, an edge strip 9 is made of ductile plastic or elastic material, for example, mineral wool. Taking into account the thickness of the edge strips 9, the wall element 3c is correspondingly smaller in its corresponding size.

Between the innermost and outermost wall elements 3b, 3c, one or more intermediate wall elements can be provided, for example three intermediate wall elements 3d, 3e, 3f. The wall element 3d adjacent externally to the innermost element 3b preferably consists of a heat-insulating material, for example, refractory lightweight brick, insulating concrete, porous material or porous brick, such as, for example, known under the trade name "Porotherm", or of the corresponding thermal insulation material, such as thermal insulation boards.

On the outside of the intermediate wall element 3d there is another intermediate wall element 3e, the material of which, preferably, is also heat-insulating, for example insulating concrete, and made as a heat-insulating plate. It may be, for example, a plate of calcium silicate. On the outside of the wall element 3e, or between it and the outermost wall element 3c, there is a next layer 3f of heat-insulating material, in which case, for example, it is a heat-insulating material, distributed under the trade name "Isolite".

In the case of all the above-described wall elements, in particular the internal wall plates 3d, 3e, 3f, we can talk about pre-made plates, which in most cases are available with different standard thicknesses. In order to achieve a certain thickness of the wall element when using standard and inexpensive plates, two plates or two layers of wall elements can be provided, for example of different thicknesses, the thicknesses of which give the desired thickness of the wall element. In this exemplary embodiment, the inner wall element 3e is formed of two plates, for example, of layers 3e1, 3e2, or wall elements 3e1, 3e2, of different thicknesses.

Since the vertical and horizontal dimensions of wall elements are often larger than the corresponding sizes of slabs available on the market, these layers of wall elements are integrated with such different horizontal and vertical dimensions that the dividing seams of these layers of wall elements not shown are displaced in length or vertical. Due to this, it is achieved that the butt joints of these layers of wall elements in the transverse direction are not adjacent, but overlap, which contributes to further thermal insulation and sealing.

The wall modules 3a preferably also include a vapor barrier 11 formed, for example, by a film 11a, in particular of plastic, for example Teflon or metal, for example aluminum, which can be installed between the inner wall elements 3e and 3f. Another vapor barrier 11 in the form of films 11a can be installed on the front sides of the intermediate wall elements 3d, 3e, 3f. The film 11a may, for example, be glued or fixed with a plurality of clogged pins on a wall element supporting it. Thanks to the vapor barrier 11, the sealing of the wall element 3a is also improved.

As can be clearly seen in figure 4, the narrow end surfaces of at least the intermediate wall elements 3d, 3e, 3f are in a common transverse plane. In order to achieve a good fit to the adjacent module even in the region of these ends, the edge strips 12 of plastic or elastic material, for example, of fibrous material, in particular in the form of mats, are also installed and fixed by gluing or using clogged wire pins on these ends. And in this case, the corresponding longitudinal dimensions of the wall elements 3d, 3e, 3f are made, respectively, less by the size of the edge strip 12.

Such edge strips 12a can also be installed in the region of protrusions and recesses 7a, 7b.

Suitable edge strips 9, 12, 12a are, for example, a fiber mat and a packing cord.

However, it is preferable to make one of the wall elements from a material filling the mold and then hardening. Such a wall element is poured between adjacent wall elements, so that it stably fills the existing loading space and, taking into account the total thickness D of the wall elements, accordingly fills the space remaining previously free. As a material, a heat-insulating material, known under the trade name Isolite, is suitable here. In the manner described above, for example, the wall element 3f can be manufactured and made.

In an exemplary embodiment, the protrusion 7a along the length and the recess 7b are formed on the innermost wall element 3b. This is preferably achieved due to the fact that the innermost wall element 3d is made with a length corresponding to the length L of the wall module 3a, but with a displacement along the length by an amount a of the protrusion 7, so that the corresponding length a of the recess 7b is automatically set.

An alternative or additional spike connection can be formed due to the fact that on the front side of the protrusion 7a a narrowing extension 7a1 of the protrusion is made, protruding, for example, with a trapezoidal cross-section. A matching recess 7b1 is formed on the opposite end face, into which an extension 7a1 of the protrusion of an adjacent wall module 3a enters.

In the exemplary embodiment of FIGS. 3 and 4, the innermost wall element 3b consists of two successively installed halves 3b1, 3b2 of the wall element adjacent to each other along the vertical butt joint 6c. Even with this embodiment, the halves 3b1, 3b2 of the wall element can be made with lap joints 7 and with elongation and recesses 7a1, 7b1 that engage with each other in the region 6c.

Wall modules 3a in their lower regions may comprise a base 13 extending in the longitudinal direction along the entire length L of the wall module 3a, and in the transverse direction along the entire width B or only along part of this width B. Preferably, the base 13 extends to the inner side 3g wall module 3a. Outside, the plinth 13 can end at a distance from the outside, for example, on the inside of the outermost wall element 3c, so that it is externally covered by the outermost wall element 3c. This contributes to the uniformity of the outer face on the outer side 3h.

The cap 13 preferably consists of a material poured into the mold and then hardened, in particular concrete. In this case, the base 13 is poured to the above-described wall elements of the wall module 3a or is poured, i.e. it is formed in advance in a special form, and in hardened form it is attached to the wall module correspondingly manufactured in advance and connected to it.

The above-described embodiments with a socle 13 are suitable, in particular, for such a wall 3 of the chamber, from the inner side 3g of which there is a horizontal ridge 14 located at a height h relative to the floor 5 of the chamber. A transport device 15 is installed in the cavity 2, on which structural elements 16 of ceramic or similar material to be dried or annealed are installed, which are transported to or through the working chamber 1. In the case of the transport device 15 we can talk, for example, about one or about a number of sequentially installed trolleys entering the working chamber 1 or passing through it on wheels. For such an installation, it is essential that the rib 14 ends near the transport device 15, so that it forms a barrier, or a separation element, between the upper part 2a and the lower part 2b of the cavity in the existing gap 17 relative to the inner side 3g of the wall 3 of the chamber or wall module 3a . This clear separation allows the processing of the structural elements 16 in the upper part 2a of the cavity at a desirable high temperature in the chamber, and the lowest possible temperature is created in the lower part 2b of the cavity, since the workspace is not in the lower part 2b, and therefore, for reasons of energy conservation and environmental protection, the temperature should be as low as possible.

Due to the relatively low temperature in the cavity part 2b in the region below the transverse rib 14, at least one wall element of heat-insulating material can be discarded, and the base element 13 can be made of a less heat-sensitive material than the material of the innermost wall element 3b. Therefore, the base element 13 can be made simpler and more economical from the molding material, for example concrete, with a relatively high heat sensitivity, without fear of damage to the base 13 from heating.

In the inner and upper regions of the base element 13, it is possible to provide for the installation of a material with lower heat sensitivity and, for example, its use in molding the base 13 and thereby pouring, or concreting. In the case of this material, we can speak, for example, of a plate-like element 13c, consisting of a heat-resistant, for example, ceramic material and formed in the example of execution of bricks mounted on top of each other.

The protrusions and recesses 7a, 7b or the lap joint 7 could extend only in the upper region of the wall module, for example, from its upper edge to the level of the rib 14, since as much insulation as possible is desirable at this level. However, it is preferable to also perform a lap joint 7 over the entire height H, namely, even in the base 13.

In an exemplary embodiment, the lap joint 7 in the height region of the cap 13 relative to the lap joint sections 7 located above the plank 14 is made with an outward shift, see FIG. 2. However, the lap joint 7 could also be made continuous vertically.

The outer wall element 3e preferably covers at least the upper region of the outer side 13d of the base 13 and is mounted on this side 13d. For this, at least two attachment points are located in the front and rear end regions of the base, in particular in its upper region. To simplify and strengthen the fastening, two fasteners 13e are located in the base 13, located at both fastening points, which could consist, for example, of steel and be sliding couplings. In the attachment points 13e, for example, profiles of the frame 8 of the outer wall element 3e are fixed, for example welded.

Thus, the profiles of the frame 8 are also fixed in the upper region of the wall module 3a on two fastening elements 18 installed at the ends, to which wall anchors 19 are connected, passing through the holes in the wall elements 3e, 3f and hooked to the innermost wall element 3b.

In order to save weight and material, it is preferable to produce a base 13 with a cavity 13f formed during molding of the base material. To do this, use the corresponding rod 13g, in which case we can speak, for example, of a formwork pipe of the corresponding length L, which is inserted before molding into the molding space of the base 13 and is fixed in it, as has already happened with the fasteners 13e.

The rib 14 may consist of the same material of which the innermost wall element 3d also consists, in particular of fireclay. The rib 14 preferably extends from the plank-like base of the rib 14a extending in the longitudinal direction continuously between the plinth 13 and the innermost wall element 3b or in the form of several successively installed elements. To strengthen the fastening between the innermost wall element 3d and / or the base 13, a corresponding geometrical engagement is provided, which can be formed, for example, by protrusions 14b from the upper and lower sides based on the ribs 14a, extending into the corresponding recesses 14c on the upper side of the basement element 13 and on the underside of the innermost wall element 3b. In the area of the substrate 14a, the lap joint 7 may be interrupted.

In the case of the base 13, we can talk about the upper base element 13A, extending upward from the lower base element 13a, which can be made integrally with the upper base element 13a or in two parts and also consists of a cast and then hardening material, for example also made of concrete. The lower base element 13b extends, preferably, to the outer side 3h of the wall module 3a, which grips the outermost wall element 3c from below, and the latter rests on the lower base element 13b. From the inner side 3g, the lower base element 13b can extend inwardly behind the innermost wall element 3b and in its upper inner corner region carry a shelf that extends upward, which is part of an angle, the other shelf of which lies on and is fixed to the lower basement element 13b.

The wall modules 3a have, respectively, two receiving holes 21 for the lifting arms of the installation and lifting device, for example, forks of a fork truck not shown, with which the wall module 3a is transported and moved for its installation and dismantling.

The receiving holes 21 on one side of the wall module 3a or on two opposite sides are open and, thus, are accessible from the outside, and they can be through. In this exemplary embodiment, the receiving holes 21 from the inner side 3g and / or from the outer side 3h are open and are thereby accessible. They are formed by adjacent pipes 22, for example, of steel, which are poured or concreted into an existing basement device, and are located, for example, in the lower basement element 13b, preferably on its upper side, and are also installed, for example, on its end surfaces 6a, 6b . To strengthen the fastening in the cross section of, preferably, rectangular pipes 22, for example, plate anchors 23 can be inserted into the upper base element 13a and filled or concreted into it.

Formwork holes, i.e. cavities 13f, or pipes 22, may be closed by closing elements.

By fixing, for example, by welding the profiles of the frame 8 with pipes 22, two internal mounting points for the external wall element 3c on the base 13 are formed.

The wall modules 3a from their lower side, namely from the side of their supporting surface, are made with an underestimated size U, i.e. with its correct mounting position in height, the lower side is located at a distance U from the chamber floor. This makes it possible to level the corresponding wall module 3a with washers 24, most of which are washers 24 having different thicknesses c, so that the correct settings for height and horizontal are leveled by selecting and lining the respective washers 24. After this, the distance U is closed, for example, filled with a casting mass.

For supplying or discharging hot air or flue gas, a transverse through pipe 25 is made in the wall module 3a, which consists of a heat-resistant material, for example, fireclay, and is also sealed and secured in an existing through-hole with a heat-resistant material, for example, packing and / or ceramic fiber material.

On the upper side, the coating 4 of the camera can be flat on the wall modules 3a, or the wall elements can be made buried from the outside inward by one or two steps, and the coating 4 of the camera is, respectively, stepwise and is located on the upper step surfaces of the wall elements 3b, 3c, 3e, 3f.

From the wall module 3a to the wall module 3a, the pipe 25 may have different cross-sectional dimensions, depending on the purpose. It forms the input to the installation of the inspection hole, side heat pipe, thermometer or chimney.

For the manufacture of such bushings in certain wall modules 3a of the wall 3 of the chamber, the following process steps are preferred.

The manufacture of wall modules 3A, the installation of wall modules 3A in at least one longitudinal section of the wall 3 of the chamber. The selection of holes 26 of the corresponding location and size of the cross section in certain wall modules, for example, boring wall modules 3a and installing pipes 25 in holes 26. This makes the manufacturing method simple, since wall modules 3a can be made identical with respect to holes 2, and holes 26 mounted and positioned wall modules 3a can be made accordingly.

Wall modules 3a are successfully manufactured according to the following process steps.

Fastening the frame 8 to the fastening elements of the base 13, to some extent manufactured in advance.

The manufacture of the outer wall element 3c based on the frame 8.

Manufacture, i.e. installation, other wall elements 3f, 3e, 3d, 3b.

Claims (14)

1. Wall module (3a) for the wall (3) of the drying chamber, the firing chamber or the tunnel kiln chamber for the manufacture of structural elements (16) made of ceramic material, containing many layers, the inside of which is made of heat-resistant material, the base (13) in in its lower region, at one or both longitudinal ends, respectively, the horizontal projection (7a) or at one or both longitudinal ends, respectively, a recess (7b) for receiving the protrusion (7a), the layer forming the protrusion (7a) or of (7b), located at offset. 2. Wall module (3a) according to claim 1, characterized in that the width of the protrusion (7a) and the corresponding recess (7b) correspond only to part of the thickness (D) of the wall module (3a). 3. Wall module (3a) according to claim 1, characterized in that the protrusion (7a) or recess (7b) is made at a distance from the outside (3h) of the wall module (3a). 4. Wall module (3a) according to claim 1, characterized in that the protrusion (7a) and / or recess (7b) extend from the upper end of the wall module (3a) only in the region of the highest height or pass continuously or discontinuously also in the lower the height of the wall module area (3a). 5. Wall module (3a) according to claim 1, characterized in that it comprises several wall elements (3b, 3c, 3d, 3e, 3f) extending along the length, and the protrusion (7a) and / or recess (7b) are made on internal or on the innermost wall element (3b). 6. Wall module (3a) according to any one of claims 1 to 5, characterized in that it comprises on the inner side (3g) a protruding rib (14) located at a distance (h) from the lower edge of the wall module (3a) and passing along the entire length (L) of the wall module (3a). 7. The wall module (3a) according to claim 6, characterized in that it comprises a base (13) under the rib (14) from the material being poured into the mold and then hardened. 8. Wall module (3a) according to claim 7, characterized in that the base (13) extends outward up to the outer side (3h) of the wall module (3a) or only to the outer wall element (3c) of the wall module (3a) . 9. Wall module (3a) according to claim 7 or 8, characterized in that the base (13) extends inward up to the inner side (3g) of the wall module (3a) or up to the inner base element (13c) of a heat-resistant material located at least in the upper region of the base (13) on the inside (3g) and formed by one or more bricks mounted on one another, molded during molding of the base (13). 10. Wall module (3a) according to claim 1, characterized in that it contains in the lower region two receiving holes (21) with a horizontal distance between them, made in the base (13) and designed for lifting arms of the device for moving the wall module ( 3a). 11. Wall module (3a) according to claim 10, characterized in that the receiving holes (21) are accessible from the outside and / or from the inside and are preferably made through. 12. Wall module (3a) according to claim 10 or 11, characterized in that the receiving holes (21) are formed by sealed pipes (22). 13. Wall module (3a) according to any one of claims 1 to 5, characterized in that the external wall element (3c) comprises a frame (8) fixed to the base (13) of the wall module (3a). 14. Wall (3) of the drying chamber, firing chamber or tunnel kiln chamber for the manufacture of structural elements (16) from ceramic material, characterized in that the wall (3) of the chamber consists of wall modules (3a) according to one of claims 1 to 13 sequentially installed in its longitudinal direction.

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