JP4748900B2 - Water tube boiler - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a natural circulation water tube boiler used for business use, air conditioning, industrial use, and power generation.
[0002]
[Prior art]
As shown in FIG. 1, the conventional water tube boiler is provided with an unheated downcomer 30 that is independent from the group of evaporating water tubes 3 (heated uppipe) as shown in FIG. The water was distributed to the respective evaporation pipes 3 through the lower pipes 2, thereby constituting a water circulation loop of the brackish drum 4, the non-heated downcomer 30, the lower pipe 2, the evaporation pipe 3 group, and the brackish water drum 4.
[0003]
Since this downcomer pipe is provided as non-heated outside the hot gas passage, it has many bent parts due to restrictions of brackish water drum, evaporating water pipe group and hot gas passage.
[0004]
In recent years, a so-called multi-pipe once-through boiler that supplies water from the lower part of the evaporating water pipe group without the precipitation pipe is sometimes used.
[0005]
[Problem to be Solved by the Invention]
In this way, in conventional water tube boilers, the downpipe is subject to thermal and physical restrictions different from those of the evaporative water tube group, so it has to take a protruding piping route that is isolated from the boiler body. There wasn't. Therefore, the distribution pipe to the lower part of the downpipe and the evaporation pipe requires extra space, and processing and assembly take a lot of time.
[0006]
Furthermore, when a so-called multi-tube type once-through boiler that supplies water from the lower part of the evaporative water tube group is used, the water circulation performance is inherently poor, and damage to the water tube such as burning of the water tube or thermal fatigue is inevitable, which is safe. There was a problem in reliability and reliability.
[0007]
As described above, in the conventional water tube boiler, etc., there is a problem in the structure of installation of the downcomer and the manufacturing cost is increased, and a water tube boiler including simplification of the downcomer loop is realized. With the goal.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a part of the water pipe group connected to the upper and lower pipes and provided with a plurality of pipe rows is appropriately set as an unheated downcomer, the other as a heated riser, It is intended to provide a water tube boiler provided with a heat insulating wall between the unheated downcomer.
[0009]
By connecting the unheated downcomer with fins, it is possible to make a structure sealed against combustion gas.
The upper pipe is provided with a partition for dividing the heated rise pipe and the non-heated down pipe. By providing a member for partitioning the inside of the upper pipe, a pipe group having two different functions is provided. It becomes possible to carry out with the upper pipe holder, and further downsizing is achieved.
[0011]
The upper or lower header is formed from a single container body, and has a semicircular shape with the same cross section , so that it is easier to manufacture and easy to assemble.
[0012]
In the water tube boiler, a part of the water tube group connected to the upper and lower pipes and having a plurality of tube rows is appropriately set as an unheated downpipe, and the other is divided into two as a heated riser, In the case where a heat insulating wall is provided between the heated precipitation pipes, the water pipe group connected to the upper and lower pipes is one module, and the modules are arranged in a single stage or in multiple stages in the flow direction of the high temperature gas. is there.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described based on examples with reference to the drawings.
[0015]
FIG. 2 shows a cross-sectional view of a water tube boiler having a downcomer that is one embodiment of the present invention.
[0016]
In the embodiment of the water tube boiler of the present invention, as shown in FIG. 2, the brackish water drum 4, the brackish water drum 4, and the brackish water connection tube 5 and the precipitation communication tube 7 are connected to the upper header 1, and further, The lower riser 2 is communicated with the heating riser 3 and the unheated downcomer 301. Here, the non-heated downcomer 301 has a part of the water tube group that plays the role, so it does not require any other special shape structure, so it is compact and easy to manufacture. Can be obtained.
[0017]
In particular, the inside of the upper header 1 is partitioned by the partition plate 7 because the heating riser pipe 3, the precipitation connecting pipe 7 and the non-heating precipitation pipe 301 are connected.
Therefore, in the heating riser 3, the steam rises from the partitioned chamber 10 to the brackish water drum 4 through the brackish water liaison officer 5. On the other hand, from the brackish water drum 4, the water flows out through the downcomer pipe 7 and through the partitioned chamber 11. Therefore, no special device is required, and it is only necessary to partition the inside of the upper header 1 so that it is more useful for a simple configuration.
[0018]
Moreover, since the upper header 1 or the lower header 2 is formed of a single container body, the assembly of the tube group is easy. Furthermore, as shown in FIG. 4, if the cross section is semicircular and the same in the upper and lower sides, there is an advantage that the manufacture and assembly are simplified.
[0019]
Since the partition plate 7 comes into contact with the steam and water of the heating riser 3 and the non-heated downcomer 301, in the illustrated example having a small heat transfer area, it is not necessary to cover the heat insulating material or the like. If it becomes large, it will be required.
[0020]
In addition, in the said Example, although the upper header 1 from the brackish water drum 4 was made into the common thing, and it divided into the chambers 10 and 11, as another, the chambers 10 and 11 which receive the precipitation connection pipe 7 are separate independent chambers. It is also possible to be provided as.
[0021]
Further, as shown in the plan view of FIG. 2, the plurality of heating risers 3 and the non-heating downcomer 301 are formed of one module and are unitized. This situation can also be understood from what is shown in the side view of FIG. From the brackish water drum 4, it can be seen that a precipitation connecting pipe 7 extends to each module and communicates with the upper pipe 1.
[0022]
As shown in FIG. 2, each module is provided with heat insulating walls 302 and 302 at both ends of the tube row of the plurality of heating risers 3.
Since the heat insulating wall 302 has a rectangular cross section and extends in the vertical direction, it also serves as a member that increases the strength for supporting the brackish water drum 4. Of course, the cross section is not limited to a rectangle, but can be adopted as appropriate.
An unheated downcomer 301 is provided on the side of the outer wall of these heat insulating walls 301.
In addition, only one side may be sufficient as the heat insulation wall as needed.
[0023]
Since the non-heated downcomer 301 can be installed compactly on the outer wall side of the heat insulating wall 301, the overall structure can be reduced in size.
[0024]
Furthermore, when modularized, there is an advantage that inspection and repair can be performed by taking out each unit.
[0025]
In the embodiment, the non-heated downcomer 301 is installed on the outer wall side of the heat insulating wall 301. However, as shown in FIG.
[0026]
That is, it is also possible to install the unheated downcomer 301 in the heated riser 3 by being surrounded by a heat insulating member. In this case, it must be installed so that the flow of the combustion gas is effective with respect to the heating riser 3.
In this way, it was possible to install the downpipe at an appropriate place in the water tube group by installing the heat insulating wall.
[0027]
Further, it can be seen that if the unheated downcomer 302 at both ends of the module is provided with fins 303 to form a membrane fall, it can be unitized and has advantages in manufacturing and inspection. Further, since the heat insulating walls 302 and 302 are connected by the fins 303, the combustion gas does not leak and no special furnace wall is required.
[0028]
Also, the brackish water drum 4 has a structure that can be installed at the center as shown in FIG. 3 and FIG. 4 with respect to the tube row of the heating riser pipe 3 and is not unbalanced as in the prior art. Since the drum 4 can be averaged by the heated riser pipe 3 and the non-heated downcomer pipe 301 group, it is not necessary to partially increase the strength of the pipe, and the structure can contribute to cost reduction. Become. In addition, when modularized, it is understood that manufacturing and assembly are easier.
Further, since the precipitation liaison officer 7 is also symmetrical as shown in FIG. 4, the prepared precipitation pipe 7 does not need to have different dimensions as in the conventional case shown in FIG. Since only the precipitation liaison officer 7 is required, a simplified structure can be obtained.
[0029]
Needless to say, the brackish water drum 4 can be structured so that it can be installed not only in the central part but also in one side as in the prior art, as shown in FIG.
[0030]
In this way, water from the brackish water drum 4 enters the heating riser 3 from the precipitation connection pipe 7 through the upper header 1, the non-heated precipitation pipe 301, and the lower header 2. Here, evaporation occurs, and in an air-water mixed state, the water is guided to the brackish drum 4 through the upper pipe 1 and the brackish water contact 5.
[0031]
【The invention's effect】
The water tube boiler of the present invention uses a part of the water tube group without providing an independent non-heated downpipe outside, so that it does not require a separate tube, is compact, and is easy to manufacture and maintain. The same water circulation circuit can be obtained.
[0032]
Further, since the water pipe group connected to the upper and lower pipes is made into one module and the module is arranged in a single stage or a plurality of stages in the flow direction of the high temperature gas, manufacturing and maintenance becomes easier.
[Brief description of the drawings]
FIG. 1 is a diagram showing a relationship between a brackish drum, a heating riser pipe, and an unheated downcomer pipe of a conventional water tube boiler.
FIG. 2 is a diagram showing a relationship between a heating riser, a heat insulating wall, and an unheated downcomer of a water tube boiler that is one embodiment of the present invention.
FIG. 3 is a plan view of a heating riser, a heat insulating wall, and an unheated downcomer of the water tube boiler in FIG.
4 is a side view of the water tube boiler shown in FIG. 2. FIG.
FIG. 5 is a diagram showing the relationship between a heating riser, a heat insulating wall and an unheated downcomer of a water tube boiler that is another embodiment of the present invention.
FIG. 6 is a diagram showing the relationship between a heating riser, a heat insulating wall and an unheated downcomer of a water tube boiler that is another embodiment of the present invention.
[Explanation of symbols]
1 Upper tube 2 Lower tube 3 Heating riser (evaporator)
301 Non-heated precipitation pipe 302 Heat insulation wall 4 Brackish water drum 5 Brackish water communication pipe 6 Partition plate 7 Precipitation communication pipe 10, 11 chamber

Claims (5)

In the water tube boiler, a part of the water tube group connected to the upper and lower pipes and having a plurality of tube rows is appropriately set as an unheated downpipe, and the other is divided into two as a heated riser, A water tube boiler characterized in that a heat insulating wall is provided between the heated downcomer. The water tube boiler according to claim 1, wherein the unheated downcomer is coupled with fins. The water pipe boiler according to claim 1 or 2, wherein a partition portion for diverting the heated riser pipe and the non-heated downcomer pipe is provided in the upper pipe holder. The water pipe boiler according to claim 1, wherein the upper header or the lower header is formed of a single container and has a semicircular shape having the same cross section. In the water tube boiler, a part of the water tube group connected to the upper and lower pipes and having a plurality of tube rows is appropriately set as an unheated downpipe, and the other is divided into two as a heated riser, In the case where a heat insulating wall is provided between the heated precipitation pipes, the water pipe group connected to the upper and lower pipes is one module, and the modules are arranged in a single stage or multiple stages in the flow direction of the high temperature gas. Features a water tube boiler.

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