JPS63207949A - Structure of boiler body - Google Patents

Abstract

PURPOSE:To provide the structure of a boiler body of pressure-resistant, of highly heat- exchanging efficiency, simply manufactured, and of low manufacturing cost, by composing a boiler body of a combustion cylinder to which a burner is installed in the axial direction of a combustion chamber, of a heat-exchanging cylinder to exchange the heat of combustion gas, and of a connecting passage, and by fitting a detachable straightening cylinder in which straightening plates are spirally disposed in the heat-exchanging cylinder. CONSTITUTION:A combustion gas exchanges heat by hitting against the water cooling wall consisting of the bottom of a combustion cylinder 19, being cooled, and is fed into a heat- exchanging cylinder 14, passing through a connecting passage 15. Therefore there is no possibility of overheating of a straightening cylinder 17 which may be caused by the radiation of flames. The combustion gas rises up along the heat-exchanging cylinder 14, rotating, guided by the straightening plates 16 of a rectifying cylinder 17. At that time efficient heat-exchanging can be performed because the gas contacts to the outside of a heat-exchanging cylinder 14 so as to lick the cylinder by the centrifugal force acting on the combustion gas. The distance of the pitch of straightening plates 16 are gradually decreased in accordance with the decrease of the volume of combustion gas as it is cooled, so that highly efficient heat- exchanging can be performed, keeping the flowing rate of combustion gas constant, and the combustion gas is discharged from the port 20 connected to a stack.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a boiler body structure, and more specifically, to a boiler body that has a simple cylindrical structure to reduce manufacturing costs while maintaining good heat exchange efficiency. Regarding the main body structure.

INDUSTRIAL APPLICATION This invention can be suitably utilized for a small boiler, a simple boiler, etc., for example.

[Conventional technology]

FIG. 8, FIG. 9, and FIG. 10 are sectional views of a conventional boiler main body. In the figure, 31 is a burner, 32 is boiler water, 33 is a combustion cylinder, 34 is a heat exchange cylinder, 37 is a rectifier cylinder, 38 is an outer frame, 3
Reference numeral 9 indicates a combustion chamber, 40 indicates a chimney connection port, and 44 indicates a smoke pipe.

In the case of a conventional boiler main body structure, for example, the furnace tube smoke tube type that connects the main stream of the current boiler, as shown in Fig. 8, the combustion tube 3
3 (combustion chamber 39) A plurality of smoke pipes 44 are welded and connected from the upper part with good watertightness and airtightness, and the space between these can bodies and the outer frame 38 is filled with boiler water 32.

Oil or gas is combusted in a combustion chamber 39 by a burner 31, and the resulting high-temperature combustion gas is heat exchanged with boiler water 32 through a combustion tube 33 and a smoke pipe 44 to raise the temperature of the boiler water. The boiler water 32 is sequentially supplied from a water supply port provided at the bottom of the outer frame 38, and the heat-exchanged boiler water is sent out from the tap at the top.

This furnace and smoke tube type has a plurality of heat exchange tubes 34 connected to the combustion tube 33, so it has excellent heat exchange efficiency, but since the boiler body structure is complicated, the welded parts require watertightness and airtightness. There are many cases, requiring advanced technology to produce and increasing costs.

The single-tube type shown in Fig. 9 simplifies the structure of the boiler body by placing the combustion tube 33 and the heat exchange tube 34 in the same cylinder, and reduces the cost by reducing the number of welded parts (although it is possible to The temperature of the combustion gas coming out of the port 40 is about 400°C, which is high and has poor heat exchange efficiency.Furthermore, the bottom of the rectifying tube 37, indicated by B, is not cooled by boiler water and becomes high temperature as it receives flame radiation in the combustion chamber 39. Therefore, unless it has high heat resistance, durability will deteriorate.

Therefore, as an improved version of the single cylinder type, as shown in FIG.
3 (heat exchange cylinder 34) at the C part to create a water-cooled wall for the boiler water and suppress overheating, but conversely, constricting the C part complicates the structure and increases costs.

Conventional boiler bodies commonly have a heat exchange tube 34 or a smoke tube 44 arranged on the combustion tube 33, so they tend to be long in the vertical direction, but due to the boiler installation location and maintenance considerations, it cannot be made that long, and the burner 31 There are many types that burn from the side. For this reason, as shown in FIGS. 8 to 10, the combustion chamber 39 has a height L2 in order to secure the volume necessary for combustion.
By suppressing the diameter D2 and making it relatively large, Lxlox is
It was about 1.5. The larger the diameter D2, the weaker it becomes against external water pressure, and in order to increase the intolerance pressure of the combustion chamber against boiler water, it is necessary to strengthen the combustion tube by adding folds called bulges, or to increase the thickness of the tube mouth body. etc. were being carried out.

[Problem that the invention seeks to solve]

As mentioned above, the structure of conventional boiler bodies becomes complicated when trying to increase the heat exchange efficiency by widening the heat transfer area of the heat exchange part, as seen in the improved smoke tube type and single tube type. On the other hand, if you try to reduce the cost with a simple structure like a single cylinder type, the heat exchange efficiency becomes poor. As described above, in the boiler body structure, it is currently not easy to satisfy the conflicting demands of reducing manufacturing costs and improving heat exchange efficiency.

Also, the combustion chamber 39 of the conventional boiler has a diameter D compared to the height L2.
Because it is necessary to take a large t (conventionally, Lxlox = 1 to 1
．． 5) If a bulge is inserted to increase the pressure resistance against boiler water pressure, or if the thickness of the combustion tube is increased, the cost increases.

The present invention was created in view of the above-mentioned problems, and an object thereof is to provide a boiler main body structure that has pressure resistance, high heat exchange efficiency, simple structure, and low manufacturing cost.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides a boiler body structure in which combustion heat of a burner 11 is exchanged with a heat medium 12, as shown in FIGS. An attached combustion tube 13°, one heat exchange tube 14 that is independent of the combustion tube 13 and exchanges heat with the combustion gas from the combustion tube 13, and a communication path 15 that connects the combustion tube 13 and the heat exchange tube 14. A removable rectifying cylinder 17 having a rectifying plate 16 spirally disposed therein is installed in the heat exchange cylinder 14.

The burner 11 is a combustion device that serves as a heat source for a boiler,
For example, oil burners, gas burners, etc. are preferable as the heat medium 1.
2, boiler water is generally used.

C. The combustion tube 13 is a cylindrical container in which the burner 11 is combusted, and the space therein is called a combustion chamber 19. The combustion cylinder 13 has a pressure-resistant cylindrical shape or a similar structure to receive the water pressure of boiler water. Mounting the burner 11 in the axial direction of the combustion chamber means that the burner outlet is mounted in the same direction as the axis of a cylindrical or similarly shaped combustion chamber (in the direction of the cylindrical shape). By making the flame elongated, the diameter of the combustion chamber can be reduced.

The heat exchange cylinder 14 is a cylinder that exchanges heat of the combustion gas from the combustion cylinder 13 with the heat medium 12. The heat exchange cylinder 14 has a cylinder structure independent from the combustion cylinder 13.

A rectifying cylinder 17 is removably mounted within this heat exchange cylinder. The rectifier tube 17 includes a rectifier plate 16 spirally arranged in the rectifier tube 17 so that the combustion gas does not pass through the heat exchange section.
This allows the combustion gas to exchange heat efficiently. This is because centrifugal force acts as the combustion gas rotates along the spiral straightening plate 16, and the combustion gas comes into contact with the outer heat exchange cylinder 14, so heat transfer on this surface is good. This is to increase efficiency. Rectifier tube 1
7, a preferable structure is to insert a heat insulating material or a heat insulating material inside, make the gap between the straightening cylinder 17 and the heat exchange cylinder 14 as small as possible (for example, about 17 mm), and install the straightening plate 16 in a spiral shape in the gap. This is what was placed. Since the rectifier plate 16 is provided in the rectifier cylinder 17 inside the heat exchange cylinder 14, watertightness and airtightness are not required for welding, and processing is easy. It is desirable that the pitch width of the spiral of the baffle plate 16 be changed in accordance with the reduction in volume due to cooling of the combustion gas, and that the flow velocity of the gas be kept constant. The current plate may have two or more spirals.

The communication path 15 has an independent combustion tube 13 and a heat exchange tube 14.
This is a pipe that communicates between the two and sends combustion gas.

The configuration of the other invention is, as shown in FIGS. 1, 2, 5, and 6, in a boiler body structure in which combustion heat of a burner 11 is exchanged with a heat medium 12, the burner 11 is Combustion tube 13 installed in the axial direction of the chamber, the combustion tube 13
a plurality of heat exchange cylinders 14a that independently exchange heat with the combustion gas from the combustion cylinder 13, and a communication path 15a that communicates between the combustion cylinder 13 and the plurality of heat exchange cylinders 14a, respectively,
Inside each of the heat exchange tubes 14a, a removable rectifying tube 17 having a helically arranged rectifying plate 16 is installed.

The number of the plurality of heat exchange cylinders 14a can be two or more depending on the heat output, but it is preferably about 2 to 4, and in reality, if the number is more than this, the structure will become complicated. There are few benefits such as cost.

This invention can provide a plurality of heat exchange cylinders depending on the desired output, whereas the previous invention had one heat exchange cylinder for each combustion cylinder.

The explanation of the constituent elements is similar to the previous invention.

[Effect]

The boiler body structure of the present invention has the burner 11 attached to the combustion tube 13 in the axial direction of the combustion chamber, and the combustion tube 13 and the heat exchange tube 14 being made independent. Since the ratio (length)/(diameter of cylinder) can be reduced to 4 to 6, a simple and pressure-resistant structure can be easily obtained.
Can be manufactured at low cost.

Since the combustion tube 13 and the heat exchange tube 14 are separated and connected by the communication passage 15, the rectifier tube 17 is not directly exposed to flame radiation. Therefore, there is no need to perform heat-resistant treatment on the rectifier tube, and costs can be reduced.

The rectifier tube 17 inside the heat exchange tube 14 is removably attached, so that maintenance and the like can be easily performed.

By arranging the baffle plate 16 spirally in the baffle tube 17, the combustion gas can efficiently exchange heat with the heat exchange wall without leaking through the tube.

In another aspect of the invention, in addition to the above-mentioned effects, it is possible to easily cope with the above-mentioned effects by providing a plurality of heat exchange cylinders corresponding to the heat output.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

Note that the present invention consists of two inventions regarding the boiler main body structure, one in which there is one heat exchange cylinder and the other in the case that there are multiple heat exchange cylinders. Next, only the parts specific to the case where there are a plurality of heat exchange cylinders will be explained in Example 2. (Figures 1 and 2 are drawings common to the embodiments of both inventions.) Figure 1 is a vertical sectional view of the boiler main body of this embodiment, Figure 2 is a partial sectional view of the rectifier tube, and Figure 3 is a cross-sectional view taken along the line A-A in FIG. 1 of Example 1, FIG. 4 is a top view of Example 1, FIG. 5 is a cross-sectional view taken along the line A-A in FIG. 1 of Example 2, and FIG. 6 is an example The top view of No. 2 and FIG. 7 are line diagrams showing the temperature change of the combustion gas temperature depending on the height of the heat exchange cylinder.

Example 1 Example 1 was implemented as a simple boiler.

In FIG. 1, which shows a longitudinal section of the boiler main body of Example 1, a burner 11 using oil is installed from above a cylindrical combustion chamber 19 toward the axial direction of the combustion chamber (in this case, downward).

The individual combustion tubes 13 and heat exchange tubes 14 are arranged so that two cylindrical tubes are erected in the outer frame 18 of the boiler body, and a heat medium (boiler water) 12 is placed between the outer frame 18 and the outer frame 18. Filled with The combustion tube 13 and the heat exchange tube 14 are connected at the lower part by a communication path 15, and the combustion gas is conveyed to the heat exchange tube 14 through this.

As shown in FIG. 2, the rectifier tube 17 installed in the heat exchange tube 14 has a hanging tool 2L 1i22. A handle 23 is attached to facilitate attachment and detachment from the heat exchange tube 14, and a heat insulating material 24 is provided inside.
In this case, a double spiral pattern of 17 mm is provided on its surface.
The width of the rectifier plates 16a and 16b are bonded together by boiling.

The operation of the boiler main body structure based on these configurations will be specifically explained below.

■The oil from the burner 11 is burned in the combustion chamber 19, generating high-temperature combustion gas.

■The combustion gas hits the water-cooled wall at the bottom of the combustion chamber 19, exchanges heat, and is cooled while passing through the communication path 15 and passing through the heat exchange cylinder 14.
to go into. Therefore, overheating of the rectifier cylinder 17 due to flame radiation does not pose a problem.

(2) The combustion gas rotates through the heat exchange cylinder 14 while being guided by the rectifier plate 16 of the rectifier cylinder 17 and rises. At this time, the centrifugal force acting on the combustion gas comes into contact with the outer heat exchange cylinder 14 so that efficient heat exchange is performed.

Therefore, although the structure is simple, unlike the conventional single cylinder type, it is possible to improve heat exchange efficiency. Since the pitch of the baffle plates 16 is gradually reduced in response to the reduction in volume due to cooling of the combustion gas, the flow rate of the combustion gas can be kept constant and efficient heat exchange can be performed.

(2) The combustion gas that has been sufficiently heat exchanged and cooled is discharged from the chimney connection port 20.

(2) On the other hand, the boiler water 12 whose temperature has increased due to heat exchange is sent out from the outlet at the top of the boiler main body and supplied from the water supply port at the bottom.

In this way, the boiler main body structure of Example 1 has a simple structure, so it can be manufactured at low cost, maintenance can be performed easily, and it has high heat exchange efficiency.

Example 2 The basic configuration of Example 2 is the same as Example 1, except that a plurality of heat exchange cylinders 14a are connected to combustion cylinder 13 by a communication path 15a.

Although the number of heat exchange cylinders 14a can be two or more,
Among these, a range of 2 to 4 is preferred (and can be implemented). This is because if the number is greater than this, the structure will become complicated and the cost reduction effect will be reduced.

In the second embodiment, as shown in FIGS. 1, 2, 5, and 6, two heat exchange tubes 14a are used to increase the heat output. , 8 XI
The boiler was O' Kcal/h.

As shown in FIG. 5, two heat exchange cylinders 14 are arranged in a V-shape for one combustion cylinder 13, and are connected to each other by a communication passage 15a. In this way, by increasing the heat output of the combustion tube 13 and increasing the number of heat exchange tubes 14a, 20 x 10'Kcal
/h boiler can be easily manufactured.

Although the boiler structure of Example 2 is somewhat more complicated than that of Example 1, it can be manufactured at a sufficiently low cost compared to the conventional example, is easy to maintain, and has high heat exchange efficiency. You can prepare.

This is shown below in Fig. 8, which is a conventional example of a furnace and smoke tube boiler (heat output cuff, OXIO' Kcal/h, combustion chamber diameter Dg = 3).
90ml1l11 Combustion chamber length L z = 55On+m,
outer frame height = 1030 mm) and the boiler of Example 2 of the present invention (
Fever cuff, 8 X 10'Kcal/h.

Combustion chamber diameter Dz ”” 200mm+, combustion chamber length L
t = 1100mn+.

This will be explained in detail by comparing with the outer frame height = 1030 mm.

If we look at the temperature change of the combustion gas according to the height of the heat exchange cylinder in the line diagram in Figure 7 (the dotted line and the solid line are the temperatures of the two heat exchange cylinders), we can see that the combustion gas entering the heat exchange cylinder gas is 7
The temperature of the gas was 00 to 800°C, but after the heat exchange, the gas temperature was cooled to about 240°C. Comparing this with a conventional boiler of approximately the same size, the exhaust gas temperature is as high as approximately 400°C in a single-tube type, and 300°C in an improved type of single-tube type.
It can be seen that the efficiency of the boiler main body structure of Example 2 is excellent.

Furthermore, the efficiency can be compared with the conventional example using the furnace load (FL).

Furnace load is the value obtained by dividing the input by the combustion chamber volume, and is expressed by the following formula.

The input and combustion chamber volume are determined by the following formula.

The furnace load value calculated from the above formula is: 80 to 120 XIO' Kcal/h/
For m3 Example 2: 200-300 XIO'K
cal/h/m'. If the value of this furnace load is large, it means that a large output can be produced even though the combustion chamber volume is small. Therefore, in Example 2, the output per unit volume of two combustion chambers is about twice as high as that of the conventional example. can be obtained. Also, if the output is the same, the boiler body structure can be made more compact.

〔Effect of the invention〕

As described above, the boiler main body structure of the present invention allows the diameter of the can part to be reduced, which increases the structural pressure resistance and reduces material costs.The boiler main body has a simple can structure and is easy to maintain. Moreover, it was possible to reduce the manufacturing cost and to achieve high heat exchange efficiency.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view of the boiler body of this embodiment, Fig. 2 is a partial sectional view of the straightening tube, Fig. 3 is a sectional view taken along line A-A in Fig. 1 of Embodiment 1, and Fig. 4 is Embodiment 1. 5 is a sectional view taken along the line A-A in FIG. 1 of Example 2, FIG. 6 is a top view of Embodiment 2, and FIG. 7 is a change in combustion gas temperature depending on the height of the heat exchange cylinder. 8 to 10 are cross-sectional views of the conventional boiler main body. In Figures 1 to 7, 11 is a burner, 12 is a fuel medium (boiler water), 13 is a combustion tube, 14, 14a are heat exchange tubes, 15, 15a are connecting passages, 16, 16a, 16b are rectifier plates , 17 is a rectifying cylinder, 18 is an outer frame, 19 is a combustion chamber, 20 is a chimney connection port, 21 is a hanging tool, 22 is a lid, 23 is a handle, and 24 is a heat insulating material.

Claims (3)

[Claims] (1) A boiler body structure in which combustion heat of a burner (11) is exchanged with a heat medium (12), comprising: a combustion tube (13) to which the burner (11) is attached in the axial direction of a combustion chamber; ), one heat exchange tube (14) that exchanges heat with the combustion gas from the combustion tube (13), and a communication path (14) that communicates between the combustion tube (13) and the heat exchange tube (14).
15), wherein a removable straightening tube (17) having a straightening plate (16) arranged in a spiral shape is installed in the heat exchange tube (14). (2) A boiler body structure that exchanges combustion heat of the burner (11) with a heat medium (12), comprising: a combustion tube (13) to which the burner (11) is attached in the axial direction of the combustion chamber; ), a plurality of heat exchange cylinders (14a) that exchange heat with the combustion gas from the combustion cylinder (13), respectively communicating between the combustion cylinder (13) and the plurality of heat exchange cylinders (14a). A boiler characterized in that it is equipped with a communication path (15a), and a removable straightening tube (17) having a straightening plate (16) arranged in a spiral shape is installed in each of the heat exchange tubes (14a). Body structure. (3) The boiler main body structure according to claim 2, wherein the number of the plurality of heat exchange cylinders (14) is 2 to 4.