Heat exchange tube suitable for high-temperature flue gas

Abstract

The utility model relates to the technical field of boiler accessories, and particularly discloses a heat exchange tube suitable for high-temperature flue gas, which comprises a heat exchange tube body, 18-26 inner fins are arranged on the inner wall of the heat exchange tube body at equal intervals, and the adjacent side surfaces of every two adjacent inner fins are parallel to each other, so that a U-shaped heat exchange channel is formed between every two adjacent inner fins. The temperature of flue gas in the center of a heat exchange tube body is T DEG C, T is larger than 700 DEG C and smaller than 1500 DEG C, the height of each inner fin is h mm, the radius of the inner diameter of the heat exchange tube body is r mm, h / r is larger than 0.09 and smaller than 0.6, and a U-shaped heat exchange channel is formed between every two adjacent inner fins, so that flowing of the flue gas in the center and flowing of the flue gas on the edge are prevented from being blocked, the top ends of the inner fins are kept to be of a certain thickness, and the heat exchange efficiency is improved. The top ends of the inner fins are prevented from melting.

Description

Technical Field

[0001] The utility model relates to the technical field of boiler accessories, in particular to a heat exchange tube suitable for high-temperature flue gas. Background Art

[0002] In order to improve the heat exchange efficiency of the heat exchange tube in the prior art, inner fins are usually arranged inside the heat exchange tube to increase the heat exchange area. For example, the utility model patent with publication number CN2614340Y discloses a specific structure of a heat exchange tube. High-temperature flue gas enters the heat exchange tube and exchanges heat with the external liquid through the heat exchange tube. The internal flue of the heat exchange tube can be specifically divided into edge flue gas close to the tube wall and central flue gas located at the center of the heat exchange tube. The heat exchange efficiency between the edge flue gas close to the tube wall and the liquid outside the tube is the highest, while the heat exchange efficiency between the central flue gas located at the center of the heat exchange tube and the liquid outside the tube is the lowest. Therefore, it can be understood that the temperature of the central flue gas located at the center of the heat exchange tube is the highest. At this time, if the top end of the inner fin extends to the center of the heat exchange tube, melting will occur. Therefore, when the heat exchange tube is used for flue gases of different temperatures, how to control the ratio of the height of the inner fin to the radius of the tube body and have good heat exchange efficiency is a technical problem to be solved by the utility model. Utility Model Content

[0003] The utility model provides a heat exchange tube suitable for high-temperature flue gas, aiming to solve the problem of how to control the ratio of the height of inner fins to the radius of the tube body in the related technology, and to have good heat exchange efficiency.

[0004] A heat exchange tube suitable for high-temperature flue gas comprises a heat exchange tube body, wherein 18 to 26 inner fins are arranged at equal intervals on the inner wall of the heat exchange tube body, and adjacent side surfaces of two adjacent inner fins are parallel, so that a U-shaped heat exchange channel is formed between the two adjacent inner fins. The flue gas temperature passing through the center of the heat exchange tube body is T degrees Celsius, and 700<T<1500, the height of the inner fin is h millimeters, and the inner diameter radius of the heat exchange tube body is r millimeters, then 0.09<h / r<0.6.

[0005] Preferably, the side surfaces of the inner fins are provided with wave-shaped grooves.

[0006] Preferably, when 700<T<1000, 0.35<h / r<0.6.

[0007] Preferably, when 1000<T<1500, 0.09<h / r<0.35.

[0008] Preferably, the number of the inner fins is 22.

[0009] Preferably, the heat exchange tube body is composed of four arc-shaped plates.

[0010] Preferably, a groove is formed at one end of the arc-shaped plate, and a protrusion matching with the groove is provided at the other end.

[0011] Preferably, the heat exchange tube comprises a low-fin tube section and a high-fin tube section formed in one piece.

[0012] By adopting the above technical solution, the beneficial effects of the utility model are as follows:

[0013] 1. A U-shaped heat exchange channel is formed between two adjacent inner fins, thereby avoiding obstruction of the flow of central flue gas and edge flue gas, and keeping the top of the inner fin at a certain height and thickness to avoid melting of the top of the inner fin.

[0014] 2. The flue gas temperature entering the heat exchange tube section that is closer to the flue gas outlet of the boiler furnace is 1000-1500 degrees Celsius. At this time, 0.09<h / r<0.35, and this section of the heat exchange tube also becomes a low-fin tube section. At this time, the height of the inner fin is relatively low to avoid melting of the top of the inner fin.

[0015] 3. The flue gas temperature entering the heat exchange tube section far from the flue gas outlet of the boiler furnace is 700-1000 degrees Celsius. At this time, 0.35<h / r<0.6, and this section of the heat exchange tube also becomes a high-fin tube section. At this time, increasing the inner fin height improves the heat exchange efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the low fin tube section of the utility model.

[0017] Figure 2 It is a structural schematic diagram of the high-fin tube section of the utility model.

[0018] Figure 3 This is a schematic diagram of the structure of the third embodiment of the present invention.

[0019] Reference numerals:

[0020] 1. Heat exchange tube body; 11. Inner fins; 12. Curved plate. DETAILED DESCRIPTION

[0021] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but cannot be understood as limiting the present invention.

[0022] like Figure 1-Figure 3As shown, a heat exchange tube suitable for high-temperature flue gas includes a heat exchange tube body 1, an outer tube is sleeved on the outside of the heat exchange tube body 1, 18 to 26 inner fins 11 are arranged at equal intervals on the inner wall of the heat exchange tube body 1, and the sides of the inner fins 11 are provided with wavy grooves. The heat exchange tube body 1 and the inner fins 11 are made of silicon-aluminum alloy and the two are integrally formed. The adjacent sides of two adjacent inner fins 11 are parallel, so that a U-shaped heat exchange channel is formed between the two adjacent inner fins 11, thereby avoiding obstruction of the flow of central flue gas and edge flue gas.

[0023] The flue gas temperature passing through the center of the heat exchange tube body 1 is T degrees Celsius, and 700<T<1500, the height of the inner fin 11 is h mm, and the inner radius of the heat exchange tube body is r mm, then 0.09<h / r<0.6. This setting can keep the inner fin 11 at a certain height according to different temperatures to prevent the top of the inner fin 11 from melting.

[0024] In the first embodiment:

[0025] Since the distances between different parts of the heat exchange tube and the flue gas outlet are different, the flue gas temperatures passing through different parts of the heat exchange tube are different;

[0026] Figure 1 The heat exchange tube shown in is suitable for the case where it is close to the flue gas outlet of the boiler furnace. At this time, the flue gas heat entering this part of the heat exchange tube is relatively high, and the flue gas temperature is 1000-1500 degrees Celsius. At this time, the radius of the heat exchange tube is 30 mm, 0.09<h / r<0.35, that is: 2.7<h<10.5, and this section of the heat exchange tube is also called the low fin tube section;

[0027] Figure 2 The heat exchange tube shown in is suitable for the case where it is far from the flue gas outlet of the boiler furnace. At this time, the flue gas heat entering this part of the heat exchange tube is low, the flue gas temperature is 700-1000 degrees Celsius, the radius of the heat exchange tube is 30 mm, 0.35<h / r<0.6, that is: 10.5<h<18, this section of the heat exchange tube also becomes a high-fin tube section, at this time, increasing the height of the inner fins improves the heat exchange efficiency;

[0028] The low-fin tube section and the high-fin tube section are the front and rear sections of the same heat exchange tube, and the two are connected, that is, when the flue gas is reduced to below 1000 degrees Celsius through the low-fin tube section, it enters the high-fin tube section.

[0029] In the second embodiment:

[0030] Since the temperature of the flue gas gradually decreases when flowing through the heat exchange tube, the height of the inner fins gradually increases when the low-fin tube section transitions to the high-fin tube section.

[0031] In the third embodiment:

[0032] like Figure 3 As shown, the heat exchange tube body 1 is composed of two semicircular arc plates 12. One end of the arc plate 12 is provided with a groove, and the other end is provided with a protrusion matching the groove. This arrangement is convenient for production and assembly.

[0033] In other implementations:

[0034] The low-fin tube section and the high-fin tube section are two independent heat exchange tubes, which are respectively suitable for boiler furnace flue gas temperatures of 1000-1500 degrees Celsius and 700-1000 degrees Celsius.

[0035] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A heat exchange tube suitable for high-temperature flue gas, comprising a heat exchange tube body (1), characterized in that: 18 to 26 inner fins (11) are arranged at equal intervals on the inner wall of the heat exchange tube body, and the adjacent side surfaces of two adjacent inner fins (11) are parallel, so that a U-shaped heat exchange channel is formed between the two adjacent inner fins (11), the flue gas temperature passing through the center of the heat exchange tube body is T degrees Celsius, and 700<T<1500, the height of the inner fin is h millimeters, and the inner diameter radius of the heat exchange tube body is r millimeters, then 0.09<h / r<0.

6.

2. The heat exchange tube suitable for high-temperature flue gas according to claim 1, characterized in that: The side surface of the inner fin (11) is provided with a wave-shaped groove.

3. The heat exchange tube suitable for high-temperature flue gas according to claim 1, characterized in that: When 700<T<1000, 0.35<h / r<0.

6.

4. The heat exchange tube suitable for high-temperature flue gas according to claim 1, characterized in that: When 1000<T<1500, 0.09<h / r<0.

35.

5. The heat exchange tube suitable for high-temperature flue gas according to claim 1, characterized in that: The number of the inner fins (11) is 22.

6. The heat exchange tube suitable for high-temperature flue gas according to claim 1, characterized in that: The heat exchange tube body (1) is composed of a plurality of arc-shaped plates (12).

7. The heat exchange tube suitable for high-temperature flue gas according to claim 6, characterized in that: One end of the arc-shaped plate (12) is provided with a groove, and the other end is provided with a protrusion matching the groove.

8. The heat exchange tube suitable for high-temperature flue gas according to any one of claims 1 to 7, characterized in that: The heat exchange tube comprises a low-fin tube section and a high-fin tube section which are integrally formed.

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