JPH07110102A - Furnace wall structure of self-supporting boiler - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a furnace wall structure of a self-supporting boiler having improved strength without using truss materials or the like. [Structure] A part of a furnace front wall tube 2 of a self-supporting boiler having a tilted furnace bottom is vertically extended to a lower front wall lower head 5
The extended pipes 8 are joined by fins 1 to form a plate-shaped wall, and both ends thereof are joined to the furnace side wall pipes 3 to integrate the lower portion of the boiler into a box shape to improve the strength. In the case of a boiler having an open hearth, a part of the rear wall tube of the furnace is also vertically extended downward to the lower part of the rear wall and integrated as described above.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a furnace wall structure for a self-supporting boiler which is designed to improve the strength of the boiler.

[0002]

2. Description of the Related Art An example of a conventional furnace wall structure of a self-standing boiler will be described with reference to FIGS. The self-weight of the self-supporting boiler passes through the furnace side wall pipe 2 and the rear flue side wall pipe 14, is transmitted to the side wall lower part header 9, and is transmitted from the support 12 to the foundation 13. The front wall has a plate structure in which fins are welded between the front wall tubes 3.

In the case of an oil and gas fired boiler, as shown in FIG. 7, the front wall tube 3 bends backward in the lower part of the furnace and becomes a furnace bottom tube 7 which is connected to the lower part 6 of the rear wall of the furnace. The horizontal force in the furnace width direction during an earthquake is borne by the lower furnace side wall pipe 10, but when the dimension between a and b in Fig. 7 is large or the horizontal force is large, the front wall pipe 3 Truss 1 just below
We are building 5.

Further, a conventional furnace wall structure of a pulverized coal burning self-supporting boiler will be described with reference to FIGS. 6 and 8. The lower part of the furnace of the pulverized coal burning boiler is V-shaped and open to take out ash. The horizontal force in the furnace width direction during an earthquake is borne by the lower side wall pipe 10, but when the dimension between a and b is large or when the horizontal force is large, the trust 15 is placed just below the front wall pipe 3 and just below the furnace rear wall 4. Are working together.

[0005]

Since the conventional furnace wall structure of a self-supporting boiler corresponds to the horizontal seismic force in the width direction of the lower part of the furnace side wall, the structure of a coal-fired boiler in which a V-shaped bottom is formed at the lower part of the front wall is used. In this case, a truss is also installed on the lower part of the rear wall of the furnace, but the temperature difference between the tube panel side and the truss material is generated when the boiler is started, and play is taken at the nodes of the truss material to absorb the expansion difference due to the temperature difference. Must be provided.

[0006] Although it is a strength member of the important part of the boiler base, the fact that there is play at the node of the truss is weak against impact load during an earthquake, and the truss material is aggregate and weak against torsional deformation. There is. An object of the present invention is to provide a furnace wall structure for a self-supporting boiler which solves the above problems found in the furnace wall structure in a conventional self-supporting boiler and improves strength to be effective.

[0007]

SUMMARY OF THE INVENTION In order to solve the above problems in a self-supporting boiler having an inclined furnace bottom or an open furnace bottom, the present invention is directed to at least a part of at least one of a furnace front wall tube and a furnace rear wall tube. Vertically extending to the lower part of the front wall or the lower part of the rear wall, and connecting the extended pipes with fins to form a plate-shaped wall. The lower part is integrated into a box.

[0008]

In the furnace wall structure according to the present invention, at least a part of at least one of the lower part of the front wall of the boiler and the lower part of the rear wall of the furnace is formed into a panel wall by tubes and fins, and is joined to the lower part of the furnace side wall by welding or the like. An important part of the boiler base becomes a box shape to improve the rigidity, and the weak point at the bottom of the furnace side wall is reinforced against horizontal force during an earthquake, and the torsional strength of the boiler as a whole is improved. Further, since boiler water flows in the tube, a temperature difference does not occur, so that the strength can be improved without causing thermal stress.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to an embodiment shown in FIGS. In these figures, the same parts as those shown in FIGS. 6 to 8 are designated by the same reference numerals. The water-cooled wall furnace wall is formed in a panel shape by alternately joining pipes and fins as in the conventional case. Above the furnace bottom tube 7, the panel-shaped furnace side wall tube and the ceiling tube are solidified into a box shape together with the furnace bottom tube 7 to provide a boiler furnace with rigidity similar to the conventional one.

In the case of a furnace with a tilted bottom shown in FIG.
The furnace front wall tube 3 is divided into a furnace bottom tube 7 and a furnace front wall lower tube 8 extending vertically downward as they are, alternately one by one at the bottom, and the furnace bottom tube 7 is a bottom tube as shown in FIG. The tubes 7 are welded together by the fins 1 to form a panel. The furnace front wall lower pipe 8 is connected to the front wall lower pipe header 5 as shown in FIG. The front wall lower part header 5 is joined to the side wall lower part header 9 with a mounting hardware 11.

The lower tubes 8 of the front wall of the furnace are welded on both sides by fins 1 between the tubes to form a panel for all the lower tubes 8 of the front wall of the furnace. The corners on both sides are also welded to the furnace side wall tube 2 by the fins 1.

The furnace wall structure according to the present embodiment is constructed as described above, and the strength of the lower part of the furnace side wall of the boiler base, which has a weakness in the furnace width direction against the horizontal force at the time of earthquake, is determined by the furnace front wall tube 3
It is improved by extending a part of it, joining it with the fin 1, and joining it with the lower part of the furnace side wall tube 2 and hardening it in a box shape, and it is possible to improve the strength against the torsional deformation of the entire boiler. ing.

Further, since the boiler water flows in the front wall lower pipe header 5 and the front wall lower pipe 8, there is no temperature difference with other furnace side wall pipes 2 and the like, so that thermal stress due to the temperature difference occurs. The strength can be improved without it.

As a next example, a case where the furnace bottom opening shown in FIG. 5 is provided will be described. In the case of a coal-fired boiler, the bottom of the furnace is made into a V-shaped hopper to make an opening for ash removal. Therefore, as shown in FIG.
Similarly to the lower part of the front wall, the rear part of the furnace wall 4 is divided into a pipe for hopper and a pipe extending vertically downward for every hopper. Connect to gather 6.

The pipe extending vertically downward can be formed into a panel shape with fins 1, and the corner can be joined to the furnace side wall pipe 2 by welding to solidify the lower part of the furnace into a box shape to improve the strength. The present invention has been specifically described above based on the illustrated embodiments, but the present invention is not limited to these embodiments, and within the scope of the present invention set forth in the claims, various shapes and structures can be used. It goes without saying that changes may be made.

[0016]

As described in detail above, the following effects can be obtained by the present invention.

(1) A part of at least one of the lower part of the front wall of the furnace and the lower part of the rear wall of the furnace is vertically extended downward to form a panel wall with the tubes and fins to form the lower part of the side wall of the furnace. Since the important parts of the boiler base are box-shaped because they are joined by welding, the rigidity is improved, and the weakness in the lower part of the furnace side wall is reinforced against earthquake horizontal force, and the furnace wall of the self-standing boiler with high torsional strength as a whole boiler A structure can be provided.

(2) As described above, since the boiler water flows in the tube of the panel wall, the temperature difference does not occur at the time of starting the boiler and the strength is improved without causing thermal stress. You can

[Brief description of drawings]

FIG. 1 is a plan view showing a main part of a furnace wall structure according to a first embodiment of the present invention.

FIG. 2 is a front view showing a main part of the furnace wall structure according to the first embodiment of the present invention.

FIG. 3 is a side view showing a main part of the furnace wall structure according to the first embodiment of the present invention.

FIG. 4 shows an embodiment in which the present invention is applied to a boiler having an inclined furnace bottom, (A) is a side view, and (B) is a front view thereof.

FIG. 5 shows an embodiment in which the present invention is applied to a boiler having a bottom opening, (A) is a side view and (B) is a front view thereof.

FIG. 6 is an enlarged view of a portion C in FIG. 7B, which is a front view showing a main portion of a conventional furnace wall structure.

FIG. 7 shows a conventional furnace wall structure in a boiler having an inclined hearth, (A) is a side view and (B) is a front view thereof.

FIG. 8 shows a conventional furnace wall structure in a boiler having an open hearth bottom, where (A) is a side view and (B) is a front view thereof.

[Explanation of symbols]

 1 fin 2 furnace side wall tube 3 furnace front wall tube 4 furnace rear wall tube 5 front wall lower side pipe 6 rear wall lower side pipe 7 hearth bottom tube 8 furnace front wall lower side pipe 9 side wall lower side pipe 10 furnace side wall lower side pipe 11 installation Hardware 12 Support 13 Foundation

Claims (1)

[Claims] 1. In a self-supporting boiler having an inclined furnace bottom or an open furnace bottom, at least a part of at least one of the furnace front wall tube and the furnace rear wall tube is vertically lowered to a lower front wall lower tube, or a rear wall. It is characterized in that it extends up to the lower part of the pipe, joins the extended pipes with fins to form a plate-shaped wall, and joins both ends with the furnace side wall pipes to integrate the lower part of the boiler into a box shape. Freestanding boiler furnace wall structure.