JP2002089802A - Noise reduction structure for cylindrical boiler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce noise leaking out from a boiler. SOLUTION: A cylindrical boiler is provided with an annular upper header 1 provided to the upper part thereof, an annular lower header 2 provided to the lower part thereof, an annularly arranged row of water tubes consisting of a number of water tubes 3, 4 for connection of the upper and lower headers, and a combustion chamber 9 positioned at the center for heating the water tubes with flaming combustion. The exhaust gas resulted from the heating of the water tubes is discharged toward the circumferential direction of the boiler through the gaps made between the water tubes. The boiler is further provided with double cylindrical members 12, 13 which are disposed outside the row of water tubes for enclosure. The gap made between the double cylindrical members surrounding the boiler serves as an exhaust gas passage 11. The exhaust gas that has been discharged in the circumferential direction from inside the boiler, is rendered to discharge through the exhaust gas passage. The wall surfaces of the cylindrical members forming the exhaust gas passage are provided with sound absorbing materials 14, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a sound reduction structure in a cylindrical boiler that performs combustion in a central portion.

[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. A plurality of vertical water tubes are connected between upper and lower headers, and a water tube is heated by burning at a central portion. There is a cylindrical boiler that does. In this case, the space between adjacent water pipes is closed except for a part so that the combustion gas flows along the water pipes. If the water pipes are two rows of inner water pipes and outer water pipes, the space between adjacent water pipes in each water pipe row is
The combustion gas passage is provided between the inner water pipe row and the outer water pipe row by closing the water pipe end except for the portion where the smoke vent is provided. The combustion gas passage is connected to the combustion chamber at the center of the boiler by the inner smoke vent provided at the end of the inner water pipe, and discharged from the outer smoke vent provided at the end of the outer water pipe opposite to the inner smoke vent in the pipe axis direction. In the combustion gas passage, the water pipe facing the combustion gas passage is heated by flowing the combustion gas in the vertical direction.

[0003] A boiler generates combustion noise when performing combustion, and the generated combustion noise leaks from the chimney to the outside through the same path as the exhaust gas and becomes noise. The combustion noise also has the effect of vibrating the furnace tube of the boiler, and some of the combustion noise leaks out around the boiler through the furnace tube. In order to reduce the noise of the boiler, a noise reduction device is provided in the chimney. However, in this case, there is a problem that the structure of the chimney becomes complicated and the size becomes large.

[0004]

An object of the present invention is to reduce the noise leaking from a boiler.

[0005]

An annular upper header is provided at an upper part, and an annular lower header is also provided at a lower part, and the upper and lower headers are connected by a water tube row including a large number of water tubes arranged in a ring. Heating the water pipe by burning the flame in the central combustion chamber, the exhaust gas after heating the water pipe is a cylindrical boiler that is discharged from the gap of the water pipe in the circumferential direction of the boiler, Outside the water pipe row, a double cylindrical member having a shape surrounding the water pipe row is provided, and an exhaust gas passage is provided between the doubly provided cylindrical members so that exhaust gas discharged in the circumferential direction from inside the boiler is sent. A chimney is provided in the exhaust gas passage, and the chimney is connected to the chimney so that the exhaust gas can be exhausted through a cylindrical exhaust gas passage provided around the boiler. A sound absorbing material is provided on the wall surface of the member.

[0006]

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 the line AA of FIG. 1, and a part is extracted and enlarged. 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. The upper and lower headers are connected by a number of inner water pipes 3 and outer water pipes 4 arranged in a ring. . The inner water pipe 3 and the outer water pipe 4 are closed by a closing fin 8 parallel to the pipe axis direction between the adjacent water pipes at portions other than the end of the water pipe where the inner smoke port 5 and the outer smoke port 6 are provided. A combustion gas passage 7 is formed between the inner water pipe 3 and the outer water pipe 4. The central portion of the boiler surrounded by the inner water pipe 3 is a combustion chamber 9, and a burner 10 is provided above the combustion chamber 9.

[0007] 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. I do. The combustion gas generated in the combustion chamber 9 enters the combustion gas passage 7 through the inner smoke passage 5 and flows upward through the combustion gas passage 7. The outer smoke vent 6 in which the blocking fin 8 is not provided also in the upper part of the outer water pipe is provided on the entire circumference. The combustion exhaust gas that has passed through the combustion gas passage 7 is supplied to the outside smoke passage 6.
Through the boiler and taken out in the circumferential direction.

Outside the outer smoke opening 6, there are provided an inner furnace tube 12 and an outer furnace tube 13, which are double cylinders concentric with the central axis of the boiler, and an exhaust gas passage is provided between the inner furnace tube 12 and the outer furnace tube 13. 11
And The outer furnace tube 13 has a length approximately half the length of the water pipe, and is longer than the longitudinal length of the outer smoke passage 6.
1 is provided all around the boiler.

The exhaust gas passage 11 is connected to the combustion gas passage 7 by the outer smoke passage 6, and a chimney 17 is connected to a chimney port 15 provided in the exhaust gas passage 11, and exhaust gas is exhausted through the exhaust gas passage 11. Inner furnace tube 12 and outer furnace tube 13
A sound absorbing material 14 for absorbing combustion noise is provided on a wall surface facing the exhaust gas passage 11, and the sound absorbing material 14 is fixed by a sound absorbing material fixing member 16 having a large aperture ratio, such as punching metal. A sound absorbing material 14 for absorbing vibration of the outer furnace tube 13 is provided on a wall surface of the outer furnace tube 13 not facing the exhaust gas passage 11.

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 heats the inner water pipe 3 and the outer water pipe 4 while moving in the combustion gas passage 7, and heats the can water in the water pipe. The exhaust gas whose temperature has decreased due to the heating of the water pipe flows through the outer smoke passage 6 in the circumferential direction of the boiler, and enters the exhaust gas passage 11. The exhaust gas passage 11 is a cylindrical space, and is made longer in the vertical direction to increase the area of the wall surface relative to the volume.

When the burner 10 burns, a combustion noise is generated. Since the combustion noise travels in the air, it travels along the same path as the combustion gas and exhaust gas. When the combustion noise reaches the exhaust gas passage 11, the exhaust gas passage 11 of the inner furnace tube 12 and the outer furnace tube 13
The sound-absorbing material 14 provided on the wall surface facing to absorbs sound energy. Although it is not possible to install the sound absorbing material 14 in a place where the temperature is too high, such as in the combustion chamber 9, the sound intensity attenuates as the distance increases, so that the sound absorbing material 14
When the sound absorbing material 14 is provided in a location closer to the sound source on the upstream side of the exhaust gas flow, the sound absorbing effect of the sound absorbing material 14 can be enhanced than when the sound absorbing material is provided. By providing the cylindrical exhaust gas passage 11 around the boiler and installing the sound absorbing material 14 in the exhaust gas passage 11, the sound can be reduced compactly and efficiently, and the noise leaking from the boiler can be reduced.

Further, sound energy may vibrate the outer furnace tube 13 so that sound may leak around the boiler. Therefore, by providing the sound absorbing material 14 also on the wall surface of the outer furnace tube 13 not facing the exhaust gas passage 11, the vibration of the outer furnace tube 13 is suppressed, and the sound generated in the outer furnace tube 13 is also absorbed. In addition, noise leaking from the boiler can be reduced.

Since the sound absorbing material 14 also has a function of blocking heat, the sound absorbing material 14 is attached to the inner furnace tube 12 and the outer furnace tube 13.
Is provided, the inner furnace tube 12 and the outer furnace tube 13 are less affected by the heat of the exhaust gas, and the effect of improving the durability of the inner furnace tube 12 and the outer furnace tube 13 can also be obtained. . Furthermore, the effect of preventing the heat of the boiler from leaking to the surroundings can be obtained.

[0014]

According to the present invention, the combustion noise generated in the boiler can be efficiently absorbed, and the noise leaking from the boiler can be reduced without substantially changing the size of the boiler.

[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 opening 6 Outer smoke opening 7 Combustion gas passage 8 Blocking fin 9 Combustion chamber 10 Burner 11 Exhaust gas passage 12 Inner furnace tube 13 Outer furnace tube 14 Sound absorption Material 15 Chimney 16 Sound absorbing material fixing member 17 Chimney

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 water tube row including a large number of water tubes arranged in a ring, and a central combustion chamber is provided. Heating the water pipe by burning the flame in, the exhaust gas after heating the water pipe is a cylindrical boiler that is discharged from the gap of the water pipe in the circumferential direction of the boiler, and is more than the water pipe row. On the outside, a double cylindrical member having a shape surrounding the water tube row is provided, and an exhaust gas passage is provided between the doubly provided cylindrical members, so that exhaust gas discharged in the circumferential direction from inside the boiler is sent. By providing a chimney and connecting the chimney to the chimney, the exhaust gas is exhausted through a cylindrical exhaust gas passage provided around the boiler, and is provided on the wall of the cylindrical member forming the exhaust gas passage. It is characterized by providing sound absorbing material Sound reduction structure of cylindrical boiler. 2. The sound reducing structure of a cylindrical boiler according to claim 1, wherein a sound absorbing material for absorbing sound waves in the air is provided on a wall surface of the cylindrical member facing the exhaust gas passage. A sound reduction structure for a cylindrical boiler, wherein a sound absorbing material for absorbing vibration of a cylindrical member is provided on a wall surface not facing the exhaust gas passage.