Aluminum flat tube air cooler

Abstract

The utility model relates to an aluminum flat tube air cooler, which comprises a fan, a framework and a finned tube bundle, the finned tube bundle is fixed in the framework, the fan is arranged at the top of the framework, air flows from the outside of the finned tube bundle, the finned tube bundle adopts aluminum porous flat tubes, aluminum fins are welded on the surfaces of the aluminum porous flat tubes, and flow guide covers are arranged at two ends of the aluminum porous flat tubes. The flow guide cover is arranged in the length direction of the aluminum porous flat tube, the outer surface of the flow guide cover is an arc-shaped surface, the width of the flow guide cover is larger than that of the aluminum porous flat tube when seen from the section, the aluminum porous flat tube and the tube plate are in an inserting hole and welding mode, a U-shaped heat dissipation groove is formed in the periphery of an opening of the tube plate, and the thickness of the groove wall of the U-shaped heat dissipation groove is 1-3 mm. The aluminum porous flat tube has the advantages that air resistance is reduced, fan energy consumption is reduced, an air retention cavity is formed in the flow guide cover, heat transfer at the end is reduced, and end medium supercooling is avoided, the U-shaped heat dissipation grooves enable the welding positions of the aluminum porous flat tube and the tube plate to be welded in an equal-wall-thickness mode, and welding seam quality is good.

Description

Technical Field

[0001] The utility model belongs to the field of heat exchangers and relates to an air cooler. Background Art

[0002] Air coolers are widely used in the fields of petroleum, chemical industry, energy, metallurgy, aerospace, etc., using ambient air as the cooling medium, sweeping across the finned tubes to cool or condense the high-temperature process fluid in the tubes. Finned tubes are usually used as heat exchange elements. Finned tubes use round tubes or oval steel tubes as base tubes, and the outer surface is rolled or welded with round aluminum fins as secondary expansion heat exchange surfaces to enhance heat transfer.

[0003] Conventional finned tubes have a leeward area, where dust in the air is easily accumulated between the base tube and the fin, reducing the heat transfer efficiency and increasing the fluid resistance on the air side. At the same time, air coolers often need to set up multiple rows of finned tubes for heat exchange, and use a triangular tube layout method. The finned tubes block each other, and the dust accumulation is difficult to clean. When the medium temperature in the tube is low during winter use, due to the uneven distribution of fluid in multiple rows of tubes or changes in the external environment, the windward side of the outermost fin is prone to overcooling, ice appears in the tube, resulting in channel blockage or even failure of the entire air cooler, which cannot guarantee the long-term stable operation of the equipment.

[0004] When the fin tube is connected to the tube sheet, there is a difference in melting rate when connecting two parts with large thickness differences. The thicker one requires more heat and melts slower, while the thinner one requires less heat. Due to the heat difference, the thin part may be burned during the welding process, which is also a problem that needs to be solved. Utility Model Content

[0005] In order to solve the above technical problems, the utility model provides an aluminum flat tube air cooler.

[0006] The technical solution of the utility model is as follows: an aluminum flat tube air cooler, which is composed of a fan, a frame, and a fin tube bundle. The fin tube bundle is fixed in the frame, a fan is arranged on the top of the frame, and air flows from the outside of the fin tube bundle. The fin tube bundle adopts an aluminum porous flat tube, and aluminum fins are welded on the surface. Guide covers are arranged at both ends of the aluminum porous flat tube, and the guide covers are arranged along the length direction of the aluminum porous flat tube. The outer surface of the guide cover is an arc surface, and the width is greater than the width of the aluminum porous flat tube in the cross section. The aluminum porous flat tube and the tube plate are in a jack plus welding manner, and U-shaped heat dissipation grooves are processed around the openings of the tube plate, and the thickness of the groove wall where the U-shaped heat dissipation groove contacts the aluminum porous flat tube is 1 to 3 mm.

[0007] Preferably, the finned tube bundles are arranged in a V-shape, with an included angle between 45° and 55°.

[0008] Preferably, the length of the smooth tube section of the aluminum porous flat tube plugged into the tube sheet opening is 50 mm.

[0009] Preferably, the aluminum fins on the surface of the aluminum porous flat tube are serpentine and connected by brazing.

[0010] The air deflector and the aluminum porous flat tube are an integrally formed structure.

[0011] Preferably, the air guide cover and the aluminum porous flat tube are assembled separately, and the air guide cover is formed separately and brazed to the end of the aluminum porous flat tube.

[0012] Furthermore, the air deflector is provided with a groove corresponding to the outer contour shape of the end of the aluminum porous flat tube.

[0013] Preferably, the U-shaped heat dissipation groove has a groove width of 3 to 5 mm and a groove depth of 3 to 5 mm.

[0014] The beneficial effects of the utility model are as follows: 1) The air deflector reduces air resistance and reduces fan energy consumption. The air deflector isolates the porous flat tube from the air to form an air retention cavity, which reduces heat transfer at the end and avoids overcooling of the end medium. 2) The U-shaped heat dissipation groove makes the welding point between the aluminum porous flat tube and the tube sheet equal in wall thickness and has good weld quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the structure of an aluminum flat tube air cooler;

[0016] Figure 2 It is a structural schematic diagram of the aluminum porous flat tube of the utility model;

[0017] Figure 3 It is a cross-sectional view of the integrated structure of the aluminum porous flat tube and the air guide cover of the utility model;

[0018] Figure 4 It is a cross-sectional view of the utility model of the aluminum porous flat tube and the split assembly structure of the air guide cover (unwelded state);

[0019] Figure 5 It is a schematic diagram of the welding structure of aluminum porous flat tube and tube sheet;

[0020] Figure 6 It is a schematic diagram of the arrangement of multiple rows of round tubes and round fins in the prior art;

[0021] Figure 7 This is a schematic diagram of the arrangement of the aluminum porous flat tube of the utility model;

[0022] Figure 8 This is a schematic diagram of possible burning when welding an aluminum porous flat tube without a U-shaped heat dissipation groove to a tube sheet;

[0023] Fig. 9 yes Figure 2 AA view;

[0024] Fig.10 yes Figure 5BB view. DETAILED DESCRIPTION

[0025] like Figure 1 As shown, the aluminum flat tube air cooler consists of a fan 1, a frame 2, and a finned tube bundle 3. The fan 1 is arranged on the top of the frame 2, and the finned tube bundle 3 is arranged inside. The finned tube bundle 3 is arranged in a V shape with an angle between 45 and 55 degrees. The air flows in from the outside of the finned tube bundle 3, flows from bottom to top after passing through, and finally is discharged from the equipment through the fan 1.

[0026] like Figure 2 , Fig. 9 As shown, the finned tube bundle 3 uses an aluminum porous flat tube 4, with a 50mm light tube section reserved at both ends in the length direction, and serpentine aluminum fins 9 are brazed on both sides of the remaining length, and a guide cover 5 is set at both ends. The guide cover 5 is set along the length direction of the aluminum porous flat tube, and the outer surface of the guide cover 5 is an arc surface, and the width is greater than the width of the aluminum porous flat tube in the cross section. The middle area of ​​the finned tube bundle 3 is the medium circulation heat exchange area. The shape of the medium circulation hole of the aluminum porous flat tube 4 can be circular, rectangular, elliptical, or serrated (here refers to the shape seen from the cross section).

[0027] like Figure 3 , 4 As shown, the air guide cover 5 can be integrally formed (extruded or die-cast) with the aluminum porous flat tube 4, or the air guide cover 5 can be formed separately and then brazed to the end of the aluminum porous flat tube 4. The main functions of the air guide cover 5 are: first, it can reduce the air flow resistance; second, it can isolate the end of the heat exchange area from the air to form an air retention cavity, reduce the heat transfer at the end, and avoid the medium from being overcooled in the front channel when the external environment temperature and wind speed are high.

[0028] like Figure 4 , 5 As shown in 10, considering the efficiency of processing and manufacturing, if it is an independently formed air deflector 5, it is provided with a groove 8 corresponding to the outer contour shape of the end of the aluminum porous flat tube 4. The groove 8 is embedded and positioned with the end of the aluminum porous flat tube 4, and at the same time prevents the loss of flux during welding. The contact area is large and the connection is more firm. For the aluminum porous flat tube 4 and the rectangular tube sheet 6, a socket plus welding method is adopted. An oblong hole is opened on the tube sheet 6, and a U-shaped heat dissipation groove 7 is processed around the oblong hole. The groove width and groove depth are both 3 to 5 mm. The thickness of the groove wall in contact with the aluminum porous flat tube is 1 to 3 mm. The wall thickness of the aluminum porous flat tube 4 is also 1 to 3 mm. The thickness of the groove wall of the U-shaped heat dissipation groove 7 is equivalent to the wall thickness of the aluminum porous flat tube 4, and the thickness difference is not much. The welding melting rates of the two are close, the weld formation quality is reliable, and the pressure bearing capacity of the equipment is greatly enhanced. The grooved area can quickly dissipate the heat generated by the pipe head welding to prevent the aluminum porous flat tube 4 from being burned through due to excessive welding heat (such as Figure 8As shown, compared with steel materials, aluminum products have a low melting point and poor heat resistance).

[0029] Comparison between the utility model and the air cooler with multiple rows of round tubes and round fins:

[0030] 1. If Figure 6 , using a triangular arrangement of multiple rows of round tubes and round fin tubes, there is a dust accumulation area on the leeward side of the fin tubes ( Figure 6 The finned tubes block each other and the dust accumulation is difficult to clean. Figure 7 The utility model has a serpentine fin air passage of aluminum porous flat tube, which is straight and has no dead zone when cleaning;

[0031] 2. If Figure 6 When air flows through multiple rows of circular tubes, the flow cross-section changes continuously, resulting in large air resistance. Figure 7 The aluminum porous flat tube has the same cross-section flow and a guide cover is set at the windward end, which has small air resistance, reduces fan energy consumption, and saves energy and reduces consumption of equipment;

[0032] 3. If Figure 6 When used in winter, the temperature of the medium in the tube is low, and the windward side of the outermost fins of the multi-row round tubes is prone to overcooling, causing freezing inside the tube. A guide cover is set at both ends of the aluminum porous flat tube to isolate the end of the heat exchange area from the air, forming an air retention cavity, reducing the heat transfer at the end, and avoiding overcooling of the medium in the front channel when the external environment temperature and wind speed are high.

Claims

1. An aluminum flat tube air cooler, comprising a fan (1), a frame (2), and a finned tube bundle (3), wherein the finned tube bundle (3) is fixed in the frame (2), the fan (1) is arranged on the top of the frame (2), and air flows from the outside of the finned tube bundle (3), the finned tube bundle (3) adopts an aluminum porous flat tube (4), and aluminum fins are welded on the surface, and the characteristics are: A guide cover (5) is arranged at both ends of the aluminum porous flat tube (4). The guide cover (5) is arranged along the length direction of the aluminum porous flat tube. The outer surface of the guide cover (5) is an arc-shaped surface. The width of the guide cover (5) is greater than the width of the aluminum porous flat tube in cross section. The aluminum porous flat tube (4) and the tube plate (6) are connected by a socket and welding method. The opening of the tube plate (6) is processed with a U-shaped heat dissipation groove (7). The thickness of the groove wall where the U-shaped heat dissipation groove (7) contacts the aluminum porous flat tube is 1 to 3 mm.

2. The aluminum flat tube air cooler according to claim 1 is characterized in that: The fin tube bundles (3) are arranged in a V shape, with an included angle between 45° and 55°.

3. The aluminum flat tube air cooler according to claim 1, characterized in that: The length of the light tube section of the aluminum porous flat tube (4) plugged into the opening of the tube sheet (6) is 50 mm.

4. The aluminum flat tube air cooler according to claim 1, characterized in that: The aluminum fins on the surface of the aluminum porous flat tube (4) are serpentine and connected by brazing.

5. The aluminum flat tube air cooler according to claim 1, characterized in that: The air guide cover (5) and the aluminum porous flat tube (4) are an integrally formed structure.

6. The aluminum flat tube air cooler according to claim 1, characterized in that: The air guide cover (5) and the aluminum porous flat tube (4) are in a split assembly form; the air guide cover (5) is formed separately and brazed to the end of the aluminum porous flat tube (4).

7. The aluminum flat tube air cooler according to claim 6, characterized in that: The air guide cover (5) is provided with a groove (8) corresponding to the outer contour shape of the end of the aluminum porous flat tube (4).

8. The aluminum flat tube air cooler according to claim 1, characterized in that: The U-shaped heat dissipation groove (7) has a groove width of 3 to 5 mm and a groove depth of 3 to 5 mm.

9. The aluminum flat tube air cooler according to claim 1, characterized in that: The medium flow holes of the aluminum porous flat tube (4) are circular, rectangular, elliptical or sawtooth-shaped.

Images