JPH06323629A - Main body structure of boiler - Google Patents

Abstract

PURPOSE:To provide a boiler main body structure in which a high heat exchanging rate can be exhibited and at the same time its structure is simple and being in expensive. CONSTITUTION:A combustion cylinder 13 is constituted so that a burner is axially fixed, it is communicated with 2 to 4 heat exchanger cylinders 14 through a communication passage 15. Combustion gas produced by the combustion cylinder 13 passes through the communication passage 15, passes through two to four heat exchanger cylinder 14 and then discharged. The combustion cylinder 13 and the 2 to 4 heat exchanger cylinders 14 are arranged in the cylinder enclosed by an outer frame filled with boiler water 12. The heat exchanger cylinders 14 have a flow regulating cylinder 17 in each of them. The flow regulating cylinder 17 has a thermal insulating material therein and the combustion gas coming from the combustion cylinder 13 passes through the communication passage 15, moves along the flow regulating plate between the heat exchanger cylinder 14 and the flow regulating cylinder 17 and then the gas is discharged through the chimney connection port.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boiler body structure,
More specifically, the present invention relates to a boiler body structure in which a good heat exchange efficiency is maintained and a manufacturing cost is reduced by using the boiler body as a simple tubular structure. INDUSTRIAL APPLICABILITY The present invention can be suitably used for, for example, a small boiler and a simple boiler.

[0002]

2. Description of the Related Art FIGS. 6, 7, and 8 are sectional views of conventional boiler bodies. In the figure, 31 is a burner, 32 is boiler water, 33 is a combustion tube, 34 is a heat exchange tube, 37 is a rectification tube, 38 is an outer frame, 39 is a combustion chamber, 40 is a chimney connection port, 44 is a smoke pipe, 45 is A water supply port and 46 are tap holes. In the case of a conventional boiler main body structure, for example, a furnace tube smoke tube type which occupies the mainstream of the present boiler shown in FIG. The space between the outer frame 38 and the outer frame 38 is filled with the boiler water 32. Burner such as oil or gas
The high temperature combustion gas generated by burning in the combustion chamber 39 by 31 exchanges heat with the boiler water 32 in the combustion tube 33 and the smoke pipe 44 to raise the temperature of the boiler water, and the combustion gas advances in the direction of the arrow in the figure. It is sent to the chimney connection port 40 and is discharged from there through a chimney (not shown). The boiler water 32 is sequentially supplied from a water supply port 45 provided in the lower portion of the outer frame 38, and the heat-exchanged boiler water becomes hot water and is sent out from a hot water outlet 46 in the upper portion. This furnace tube smoke tube type is excellent in heat exchange efficiency because many smoke tubes 44 are connected to the combustion tube 33, but since there are many smoke tubes, the boiler body structure is complicated and watertightness / airtightness is required. There are many welded parts, high technology is required for production, and the cost is high. The single cylinder type shown in FIG. 7 has a combustion cylinder 33 and a heat exchange cylinder 34.
Simplifies the boiler body structure by integrating
Although the cost can be reduced by reducing the number of welded parts, the temperature of the combustion gas emitted from the chimney connection port 40 is high at about 400 ° C, indicating that the heat exchange efficiency is poor. Further, the bottom of the rectifying cylinder 37, which is indicated by B, is not cooled by the boiler water and receives flame radiation in the combustion chamber 39 to reach a high temperature, so that durability is deteriorated unless it has high heat resistance.

Therefore, as shown in FIG. 8 as an improved type of the single cylinder type, the combustion cylinder 33 and the heat exchange cylinder 34 are squeezed at the C portion so that the B portion of the rectifying cylinder 37 is not directly exposed to the flame radiation, and the boiler water is discharged. If a water cooling wall is formed to suppress overheating, the structure is complicated because the C portion is constricted, and the cost increases. In the conventional boiler body, since the heat exchange tube 34 or the smoke tube 44 is arranged on the combustion tube 33 in common, it becomes long in the vertical direction, but it cannot be so high due to the installation location of the boiler and the convenience of maintenance, and the burner 31 is used. In many cases, combustion is performed from the lateral direction as shown in FIGS. Therefore, as shown in FIGS. 6 to 8, since the combustion chamber 39 needs to secure a volume necessary for combustion, the height L ₂ is suppressed and the diameter D ₂ is made relatively large, so that L ₂ / D ₂
Was set to about 1 to 1.5. However, the larger the diameter D ₂ becomes, the weaker it becomes against water pressure from the outside, and the pressure resistance against the boiler water in the combustion chamber increases. Things are done.

[0004]

As described above, the conventional boiler main body structure has a large heat transfer area in the heat exchange portion as seen in the furnace tube type, the single tube type and its improved type. If the exchange efficiency is increased, the structure becomes complicated and the cost increases, and conversely, if the cost is reduced with a simple structure such as a single cylinder type, the heat exchange efficiency deteriorates. As described above, in the boiler body structure, it is not easy to satisfy the contradictory requirements of reduction of manufacturing cost and improvement of heat exchange efficiency. Further, since the combustion chamber 39 of the conventional boiler needs to have a diameter D ₂ larger than the height L ₂ (L ₂ / D ₂ = 1 to 1.5 in the past), the bulge is increased to increase the pressure resistance against the water pressure of the boiler water. There is a problem in that the cost is increased by putting it in or increasing the thickness of the combustion cylinder. The present invention has been made in view of the above problems, and an object of the present invention is to provide a boiler main body structure having pressure resistance, high heat exchange efficiency, simple structure, and low manufacturing cost.

[0005]

SUMMARY OF THE INVENTION The above-mentioned problem is that in a boiler main body having a combustion tube having a burner attached in the axial direction of the combustion chamber and a communication path for connecting the combustion tube to the heat exchange section, the heat exchange section is It is composed of 2 to 4 heat exchange tubes that are independent of the combustion tubes and exchange heat with the combustion gas from the combustion tubes. Inside each heat exchange tube, a heat insulating material is provided, and on the outer surface, a straightening plate is spirally formed. It is solved by providing a boiler main body structure characterized in that a detachable rectifying cylinder having the above-mentioned is mounted.

[0006]

The function of the boiler body of the present invention is such that the combustion cylinder 13 is provided with a burner.
11 is attached in the axial direction of the combustion chamber, and the combustion cylinder 13 and the heat exchange cylinder 14 are made independent of each other, so that (cylinder length) / (cylinder diameter) of the combustion cylinder 13 and the heat exchange cylinder 14 is 4 to Since the diameter can be reduced to 6, a simple and pressure-resistant structure can be easily obtained, the cost can be reduced, and the combustion chamber 13 and the heat exchange cylinder 14 are separated and are connected to each other by the communication passage 15. 17 does not directly receive flame radiation, so that it is not necessary to perform pressure resistance treatment on the rectifying cylinder, and the cost can be reduced.
Is detachably mounted, so that maintenance and the like can be easily performed. By disposing the flow straightening plate 16 in a spiral shape on the outer surface of the flow straightening cylinder 17 having the heat insulating material 24 inside, the combustion gas can escape from the cylinder. In addition to efficiently exchanging heat with the heat exchange wall without increasing the number of heat exchange walls, it also increases the heat output and heat exchange rate by using 2 to 4 heat exchange cylinders to increase the furnace load (FL). Increase.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings. Referring to FIG. 3, in the boiler body structure for exchanging the combustion heat of the burner 11 with the heat medium 12,
Combustion cylinder 13 in which 11 is attached in the axial direction of the combustion chamber 19, combustion cylinder 13
And two heat exchange tubes 14 for independently exchanging heat with the combustion gas from the combustion tube 13, and a communication path connecting the combustion tube 13 and the heat exchange tube 14
The heat exchange cylinder 14 is provided with a rectifying plate 16 arranged spirally on the outside and a detachable rectifying cylinder 17 having a heat insulating material 24 packed therein. The burner 11 is a combustion means serving as a heat source of the boiler, and for example, an oil burner or a gas burner can be preferably used, the heat medium 12 is generally water as boiler water, and the combustion cylinder 13 is connected to the burner 11. This is a cylindrical container in which the space therein is a combustion chamber 19, and the combustion cylinder 13 has a pressure-resistant cylindrical shape or a similar structure because it receives the water pressure of boiler water. Burner
Attaching 11 in the axial direction of the combustion chamber means attaching the outlet of the burner in the same direction as the axis of the combustion chamber having a cylindrical shape or a similar shape (in the case of a cylindrical shape, the cylinder direction). The diameter of the combustion chamber can be reduced by making the flame produced in the combustion chamber into an elongated flame. The heat exchange cylinder 14 is the combustion cylinder 13
This is a cylinder for exchanging the heat of the combustion gas from the heat medium 12 with the heat medium 12. The heat exchange tube 14 has a tube structure independent of the combustion tube 13. A rectifying cylinder 17 is detachably mounted in the heat exchange cylinder. The rectifying cylinder 17 has a rectifying plate 16 spirally arranged outside the rectifying cylinder 17 so that the combustion gas does not pass through a heat exchange portion, that is, a portion between the rectifying cylinder 17 and the heat exchanging cylinder 14. Allows for efficient heat exchange. That is, when the combustion gas rotates along the straightening plate 16 provided in a spiral shape, a centrifugal force acts, and the combustion gas comes into contact with the outer heat exchange cylinder 14 so as to lick it. Improves heat exchange efficiency. As a preferable structure example of the flow straightening cylinder 17,
A heat insulating material or a heat insulating material is put inside, the gap between the flow straightening cylinder 17 and the heat exchange cylinder 14 is made as small as possible (for example, about 17 mm), and the flow straightening plate 16 is spirally arranged in the gap. Since the straightening vane 16 is provided in the straightening vane 17 inside the heat exchange barrel 14, the welding is not required to be watertight and airtight, and the work is easy. The pitch width of the spiral of the straightening vanes 16 is preferably changed according to the reduction in volume of the combustion gas due to cooling, and is designed to keep the gas flow velocity constant. The spiral of the baffle plate can be double or more. The communication passage 15 is a pipe that connects the independent combustion cylinder 13 and the heat exchange cylinder 14 and sends combustion gas. In FIG. 3, a burner 11 using, for example, oil is installed from above the cylindrical combustion chamber 19 in the axial direction (here, downward) of the combustion chamber. As shown in FIG. 1, the combustion cylinder 13 and the two heat exchange cylinders 14 are arranged in such a manner that two cylindrical cylinders are erected in parallel inside the outer frame 18 of the boiler main body, and between them and the outer frame 18. Is filled with heating medium (boiler water) 12. The lower part between the combustion cylinder 13 and the heat exchange cylinder 14 is connected by a communication path 15, and the combustion gas is conveyed to the heat exchange cylinder 14 through this. As shown in FIG. 4, the rectifying cylinder 17 mounted in the heat exchange cylinder 14 is provided with a lifting tool 21, a lid 22 and a handle 23 on the upper part thereof to facilitate attachment / detachment to / from the heat exchange cylinder 14, and an insulating material 24 inside. In this case, on the surface thereof, a straightening plate 16 having a width of 17 mm and having a width of 17 mm is point-bonded in a double spiral shape. The operation of the boiler body structure having these configurations will be specifically described below. Gas or oil from the burner 11 is burned in the combustion chamber 19 to generate high temperature combustion gas. Combustion gas hits the water cooling wall at the bottom of the combustion chamber 19 and exchanges heat to be cooled and then enters the heat exchange tube 14 through the communication passage 15. Therefore, overheating of the rectifying cylinder 17 due to flame radiation does not pose a problem. The combustion gas rotates and rises while being guided between the heat exchange cylinder 14 and the rectifying cylinder 17 by the rectifying plate 16 arranged outside the rectifying cylinder 17. At this time, due to the centrifugal force acting on the combustion gas, the combustion gas comes into contact with the outer heat exchange cylinder 14 so as to lick it, and efficient heat exchange is performed. With such a simple structure, the heat exchange rate can be improved unlike the conventional single cylinder type. rectifier
Since the pitch of 16 pitches is gradually reduced in accordance with the decrease in volume due to cooling of the combustion gas, efficient heat exchange can be performed while keeping the flow velocity of the combustion gas constant. The combustion gas that has been sufficiently heat-exchanged and cooled is discharged through the chimney connection port 20. On the other hand, the boiler water 12 that has undergone heat exchange and whose temperature has risen is sent out from the hot water outlet 26 in the upper part of the boiler body, and the water is supplied from the water supply port 25 in the lower part. In this way, the boiler main body structure of the embodiment of the present invention has a simple structure, so that it can be manufactured at low cost, maintenance can be easily performed, and high heat exchange efficiency is provided.

In the embodiment of the present invention, the number of heat exchange tubes 14 is two, and the boiler has a heat output of 7.8 × 10 ⁴ Kcal / h. As shown in FIG. 1, in the present invention, two heat exchange cylinders 14 are arranged in a V shape with respect to one combustion cylinder 13 and are connected to each other through a communication path 15. By increasing the heat output of the combustion cylinder 13 and increasing the heat exchange cylinder 14 in this manner, it is possible to easily manufacture a boiler of about 20 × 10 ⁴ Kcal / h. FIG. 2 is a top view of the example shown in FIG. In this embodiment, the structure of the boiler main body is slightly different from the case where there is only one heat exchange tube 14, but it can be manufactured at a sufficiently low cost compared to the conventional example, maintenance is easy, and high heat is required. Provides exchange rate. Comparing this with a concrete example, the furnace tube smoke tube type boiler of the conventional example of FIG.
× 10 ⁴ Kcal / h, combustion chamber diameter D ₂ = 390 mm, combustion chamber length L ₂
= 550 mm and outer frame height = 1030 mm, the boiler of the present invention has a heat output of 7.8 × 10 ⁴ Kcal / h and a combustion chamber diameter D ₂ =
200 mm, combustion chamber length L ₂ = 1100 mm, outer frame height = 1030 mm. Looking at the temperature change according to the height of the heat exchange tube of the combustion gas in the line diagram of FIG. 5 (the dotted line and the solid line are the temperatures of the two heat exchange tubes), the combustion gas entering the heat exchange tube Was 700-800 ° C, but the gas temperature after heat exchange was about
It is cooled to about 240 ° C. Comparing this with a conventional boiler of almost the same scale, the exhaust gas temperature of the single cylinder type is about 40
It is understood that the efficiency of the boiler main body structure of the embodiment of the present invention is excellent because the temperature is as high as about 0 ° C., and the improved single cylinder type is also about 300 ° C. Furthermore, the efficiency can be compared with the conventional example by using the furnace load (FL). The furnace load is a value obtained by dividing the input by the combustion chamber volume and is represented by the following equation.

[Equation 1] Input and combustion chamber volume are calculated by the following equation.

[Equation 2]

[Equation 3] The value of the furnace load calculated from the above formula is 80 to 120 × 10 ⁴ Kcal / h / m ^{3 for} the conventional type and 200 to 300 × 10 ⁴ Kcal / h / m ³ for the embodiment of the present invention. It was If the value of the furnace load is large, it means that a large output can be output despite the small combustion chamber volume. Therefore, the embodiment of the present invention provides about twice as high output per unit volume of the combustion chamber as compared with the conventional example. You will be able to get it. If the output is the same, a compact boiler body structure can be obtained. Although the embodiment of the present invention has been described as using two heat exchange tubes 14 in the boiler body structure, three to four heat exchange tubes 14 are connected from the combustion tube 13 to the connecting path 15.
You can also connect by. The number of heat exchange tubes 14 can be two or more, but a smaller number is preferable and practical. However, if the number is five or more, the structure becomes complicated and the effect of cost reduction is reduced.

[0009]

As described above, in the boiler body structure of the present invention, since the diameter of the can body portion can be made small, the structural pressure resistance increases and the material cost is low, and the boiler body has a simple can body structure. As a result, the maintenance can be easily performed, the manufacturing cost can be reduced, and the heat exchange rate can be high.

[Brief description of drawings]

1 is a cross-sectional view of an embodiment of the present invention.

FIG. 2 is a top view of an embodiment of the present invention.

FIG. 3 is a vertical sectional view of a boiler body structure according to an embodiment of the present invention.

FIG. 4 is a partial cross-sectional view of a heat exchange tube.

FIG. 5 is a polygonal diagram showing a temperature change of a combustion gas temperature depending on a height of a heat exchange tube.

FIG. 6 is a cross-sectional view of a conventional boiler body.

FIG. 7 is a cross-sectional view of a conventional boiler body.

FIG. 8 is a sectional view of a conventional boiler body.

[Explanation of symbols]

 11 Burner 12 Heat medium (boiler water) 13 Combustion tube 14 Heat exchange tube 15 Communication path 16 Straightening plate 17 Rectification tube 18 Outer frame 19 Combustion chamber 20 Chimney connection port 21 Lifting tool 22 Lid 23 Handle 24 Insulation material 31 Burner 32 Boiler water 33 Combustion tube 34 Heat exchange tube 37 Rectification tube 38 Outer frame 39 Combustion chamber 40 Chimney connection port 44 Smoke pipe 45 Water inlet 46 Hot water outlet

Claims (2)

[Claims] 1. A boiler main body comprising a combustion tube (13) having a burner (11) attached in the axial direction of a combustion chamber (19) and a communication path (15) for connecting the combustion tube (13) to a heat exchange section. The heat exchange section is composed of two heat exchange tubes (14) that are independent of the combustion tubes (13) and exchange heat of the combustion gas from the combustion tubes (13). A boiler main body structure comprising a heat insulating material (24) inside, and a detachable rectifying cylinder (17) having a rectifying plate (16) arranged spirally on the outer surface thereof. 2. The boiler body structure according to claim 1, wherein the number of the heat exchange tubes (14) is 3 to 4.