JP2002048302A - Boiler having horizontal heat absorbing fins in combustion heat passage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase heat absorption rate in a multitubular boiler having a structure wherein combustion gas is made to flow into a combustion gas passage which is disposed between two inner and outer rows of water tubes. SOLUTION: A multitubular boiler has a structure wherein an annular upper header 1, and an annular lower header 2 are provided on the upper and lower portions, respectively, the upper and lower headers are connected with a number of water tubes arranged in two inner and outer rows, a combustion gas passage 7 is provided between inner water tubes 3 and outer water tubes 4, and the combustion gas is permitted to flow in the combustion gas passage 7. A number of steps of horizontal heat absorbing fins 11 are provided to portions of the inner water tubes 3 and the outer water tubes 4, respectively, facing the combustion gas passage 7. The inner water tubes 3 provided with the fins 11 consist of two kinds of water tubes, i.e., inner water tubes A having a large heating area made by the fins 11 and inner water tubes B having small heating area made by the fins 11. The inner water tubes A and the outer water tubes B are alternately arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-tube once-through boiler for flowing a combustion gas into a combustion gas passage provided between an inner water pipe row and an outer water pipe row, wherein the heat pipe has a horizontal heat absorption structure. The present invention relates to a boiler provided with fins for use.

[0002]

2. Description of the Related Art An annular upper header is provided at an upper portion, and an annular lower header is provided at a lower portion. The upper and lower headers are connected by a large number of vertical water pipes in two rows inside and outside, and combustion is performed at a central portion to form a water pipe. There is a boiler to heat. A combustion gas passage is provided between the inner water pipe row and the outer water pipe row by closing the space between adjacent water pipes in each water pipe row except for a portion where a smoke port at the end of the water pipe is provided. The combustion gas passage is connected to the combustion chamber at the center of the boiler by an inner smoke port provided at the end of the inner water pipe, and smoke is generated by an outer smoke port provided at the end of the outer water pipe opposite to the inner smoke port in the pipe axis direction. The water pipe facing the combustion gas passage is heated by flowing the combustion gas in the combustion gas passage in a vertical direction in connection with the road.

In the boiler, a horizontal heat absorbing fin is provided in a portion of the water pipe facing the combustion gas passage,
The heat absorption is increasing. As for the boiler, a small and highly efficient one is demanded similarly to a general apparatus. By providing heat absorbing fins, the amount of heat absorbed by the boiler can be increased without changing the size. When the inner and outer two rows of water pipes are provided in a ring shape, in order to reduce the installation area, the inner water pipe rows and the outer water pipe rows are arranged such that each water pipe has the same pitch angle and is shifted by a half pitch between the inside and the outside. In this case, the spacing between the water pipes in the inner water pipe row is smaller than the spacing between the water pipes in the outer water pipe row. In the case of the outer water pipe, the spacing is wide, so that heat absorbing fins can be provided between the adjacent water pipes. Cannot be provided with heat absorbing fins. Therefore, heat absorbing fins are not connected to the inner water pipe, or even if they are connected, as described in Japanese Patent Application No. H11-141368, the outer water pipe connects two heat absorbing fins to each stage, but the inner water pipe has Heat absorbing fins were connected to each stage one by one.

[0004]

An object of the present invention is to provide a multi-tube boiler having a structure in which combustion gas flows through a combustion gas passage provided between two inner and outer water pipe rows. Is to increase the amount.

[0005]

An annular upper header is provided at the upper part, and an annular lower header is also provided at the lower part. The upper and lower headers are connected by a number of water pipes arranged in two rows inside and outside, and the inner water pipe row is connected to the inner water pipe row. In a multi-tube boiler having a configuration in which a combustion gas passage is provided between the outer water pipe rows and the combustion gas flows in the combustion gas passage, horizontal heat absorption is provided at portions of the inner water pipe and the outer water pipe facing the combustion gas passage. A number of fins are provided in multiple stages, and the inner water pipe row provided with the heat absorbing fins has an inner water pipe A having a large heat transfer area by the heat absorbing fin and an inner water pipe B having a small heat transfer area by the heat absorbing fin. It consists of two types of water tubes, and the inner water tubes A and the inner water tubes B are arranged alternately.

The above-mentioned heat absorbing fins are fan-shaped fins, and the inner water pipe A is provided with a larger number of heat absorbing fins than the inner water pipe B in each step. The water pipe A has a larger heat transfer area than the inner water pipe B by increasing the number of connected heat absorbing fins.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of a boiler embodying the present invention,
FIG. 2 is a sectional view taken along line AA of FIG. An annular upper header 1 is provided at the upper part of the can body, and an annular lower header 2 is also provided at the lower part,
A number of inner water pipes 3 and outer water pipes 4 arranged in a ring are connected between the upper and lower headers. The inner water pipe 3 and the outer water pipe 4
At a portion other than the end of the water pipe in which the inner smoke outlet 5 and the outer smoke outlet 6 are provided, the space between the adjacent water pipes is closed by the closing fins 8 parallel to the pipe axis direction. A combustion gas passage 7 is formed between the water pipes 4. The central portion of the boiler surrounded by the inner water pipe 3 is a combustion chamber 9.
The burner 10 is provided on the upper part.

At the lower part of the inner water pipe, an inner smoke passage 5 without a blocking fin 8 is provided so as to surround the combustion chamber 9, and the combustion chamber 9 and the combustion gas passage 7 are connected by the inner smoke passage 5. . The combustion gas generated in the combustion chamber 9 enters the combustion gas passage 7 through the inner smoke passage 5, and the combustion gas passage 7
Flowing upwards. 8 fins for closing the upper part of the outer water pipe
A flue gas 6 which is not provided is provided, and the flue gas that has passed through the combustion gas passage 7 is taken out in the circumferential direction of the boiler through the flue gas port 6, and then the flue gas is collected and discharged from the flue. ing.

At the part of the inner water pipe 3 and the outer water pipe 4 facing the combustion gas passage, heat absorbing fins 11 in the form of a fan are horizontally arranged so that the heat absorbing surfaces intersect the combustion gas flow. Many stages are provided. The heat absorbing fins 11 connected to the inner water pipe 3 and the outer water pipe 4 use heat absorbing fins having the same shape. However, the inner water pipes 3 alternately include inner water pipes A each having two heat absorbing fins connected to each stage and inner water pipes B each having one heat absorbing fin connected to each stage. Two heat absorbing fins are connected to each stage.

Since the distance between the inner water tubes is narrow, it is not possible to provide the heat absorbing fins 11 between the adjacent water tubes. However, by arranging the inner water pipes A and the inner water pipes B alternately, the heat absorbing fins 11 are installed only on one of the water pipes between adjacent water pipes.
The heat absorbing fins 11 can be increased without increasing the distance between the water tubes. The inner water pipe A and the inner water pipe B use the same heat absorbing fins 11, and two inner water pipes A are provided in each stage.
Since the inner water pipe B is connected one by one to each stage,
The heat absorbing fins 11 can be shared, and the heat transfer area of the inner water pipe A can be increased.

When the burner 10 is burned, high-temperature combustion gas is generated in the combustion chamber 9, and the combustion gas is first supplied to the inner water pipe 3.
Is heated on the side of the combustion chamber 9. Subsequently, the combustion gas enters the combustion gas passage 7 through the inner smoke passage 5 and flows upward in the combustion gas passage 7. The combustion gas passes through the combustion gas passage 7.
The heat absorbing fins 11 are heated while moving inside, and the heat of the combustion gas passes through the heat absorbing fins 11 to heat the water in the water pipe. The inner water pipe A having two heat absorbing fins 11 in each stage has a larger heat transfer area than conventional ones, and can absorb more heat. The total volume increases. Therefore, the amount of heat absorbed by the boiler can be increased without increasing the size of the boiler.

Although the present embodiment has been described based on a boiler having a configuration in which combustion gas flows vertically through the combustion gas passage 7, the present invention is not limited to this shape.
The same applies to a boiler that allows the combustion gas to flow in the combustion gas passage 7 in the horizontal direction. The heat absorption area can be increased by increasing the heat transfer area.

[0013]

According to the present invention, the amount of heat absorbed by the heat absorbing fins can be increased without changing the size of the boiler, and the boiler efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of a boiler according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper header 2 Lower header 3 Inner water pipe 4 Outer water pipe 5 Inner smoke vent 6 Outer smoke vent 7 Burning gas passage 8 Closing fin 9 Combustion chamber 10 Burner 11 Heat absorption fin

Continued on the front page (72) Inventor Daizo Ito 3-4-1-15 Yawata-cho, Kanonji-shi, Kagawa Prefecture Inside Samson Co., Ltd.

Claims (2)

[Claims] An annular upper header is provided at an upper portion, and an annular lower header is also provided at a lower portion. The upper and lower headers are connected by a number of water pipes arranged in two rows inside and outside, and an inner water pipe row and an outer water pipe row are connected. In a multi-tube boiler having a configuration in which a combustion gas passage is provided therebetween and combustion gas flows in the combustion gas passage, a number of horizontal heat absorbing fins are provided in portions of the inner water pipe and the outer water pipe facing the combustion gas passage. The inner water pipe row provided with the heat absorbing fins is provided in two stages: an inner water pipe A having a large heat transfer area by the heat absorbing fin, and an inner water pipe B having a small heat transfer area by the heat absorbing fin. A boiler provided with horizontal heat absorbing fins in a combustion gas passage, wherein inner water pipes A and inner water pipes B are alternately arranged. 2. The boiler according to claim 1, wherein the heat-absorbing fins are fan-shaped fins, and the inner water pipes A are provided in multiple stages. The number of the absorbing fins provided in each stage is larger than that of the inner water pipe B. The inner water pipe A has a larger heat transfer area than the inner water pipe B by increasing the number of connected heat absorbing fins. A boiler provided with horizontal heat absorbing fins in a combustion gas passage.