Integrated heat removal tube bundle

Abstract

The utility model relates to an integrated heat removal tube bundle which comprises a heat removal tube body, a plurality of fins are integrally formed on the outer wall of the heat removal tube body, the fins extend in the axial direction of the heat removal tube body and are distributed in the circumferential direction of the heat removal tube body, and stress release angles are arranged at the two ends of each fin in the length direction. The heights of the two ends of the fins are gradually reduced in the direction close to the corresponding end faces of the heat removal pipe body. By means of the technical scheme, the fins and the heat removal pipe body are integrally formed, the stress generated in the axial direction and the stress generated in the radial direction are greatly improved, large welding operation space does not need to be reserved between the adjacent fins, the number of the fins can be increased under the same size, the heat removal area can be increased, and the height of the fins can be reduced. The stress release angles are arranged at the two ends of the fins in the length direction, so that stress generated between the fins and the heat removal pipe body can be released step by step, stress concentration is avoided, and abrasion of a hot catalyst to the heat removal pipe body and the fins can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of petrochemical equipment, in particular to an integrated heat extraction tube bundle. Background Art

[0002] Traditional heat pipes in the petrochemical industry, such as patent 91227483.2, are welded with axial long fins on the wall of the heat pipe to increase the heat collection area. The thermal catalyst exchanges heat with the water in the heat pipe of the heat pipe. After absorbing heat, the water in the heat pipe becomes a steam-water mixture and goes to the steam-water separator to achieve the purpose of excess heat recovery.

[0003] Combination Figure 1 It can be seen that the outer wall of the heat pipe 100 in the prior art is welded with a large number of fins 200 along the circumferential direction, and the welding place between the root of the fin and the heat pipe has a weld foot 300. The welding stress concentration coefficient at both ends of the fin length direction is relatively large. Since the 15CrMo commonly used in this field has poor welding performance, it is difficult to ensure the quality of welding and post-weld heat treatment of the fins 200 on the heat pipe, so there are certain shrinkage stress and welding residual stress; and through a large number of stress analysis, experimental data and use cases, such as "External Heat Exchanger Tube The content recorded in "Analysis and Countermeasures of Failure of Heat Extractor Bundles (Document No. 1001-4837 (2004) 04-0047-03)" clearly shows that the traditional heat extractor heat pipe, which is a form of long fins extending axially welded on the tube wall, will produce huge stress at both ends of the fin area, which is very easy to cause the heat extractor tube to rupture due to factors such as cracking and perforation caused by thermal fatigue, cracking or breaking of the weld, and wear of the external heat extractor bundle, thereby shortening the overall service life of the equipment and seriously affecting the normal production of the entire catalytic cracking unit. Utility Model Content

[0004] The utility model aims to provide an integrated heat extraction tube bundle to reduce stress in all directions of the heat extraction tube bundle and avoid damage or breakage of the tube body.

[0005] The purpose of the utility model and the technical problem to be solved are achieved by adopting the following technical solutions. The integrated heat extraction tube bundle proposed by the utility model includes a heat extraction tube body, the outer wall of which is integrally formed with a plurality of fins, the fins extend along the axial direction of the heat extraction tube body, the plurality of fins are distributed in the circumferential direction of the heat extraction tube body, and stress release angles are provided at both ends of the fin length direction, so that the height of both ends of the fins gradually decreases in the direction close to the corresponding end face of the heat extraction tube.

[0006] Furthermore, the integrated heat extraction tube bundle is formed by rolling, extrusion or machining.

[0007] Furthermore, the fins (2) are perpendicular to the outer wall of the heat pipe body (1).

[0008] Furthermore, the slope of the stress release angle is 1:10.

[0009] Furthermore, the fin gradually narrows from the root to the outer end of the fin, and the outer end of the fin is an end of the fin that is away from the heat pipe body in the radial direction.

[0010] Furthermore, the cross section of the fin is a regular trapezoid.

[0011] Furthermore, the outer end of the fin is chamfered at an arc angle.

[0012] Furthermore, a chamfered arc angle transition is performed at the connection between the root of the fin and the heat pipe body.

[0013] Furthermore, the arc radius of the arc angle at the outer end of the fin is 2-4 mm.

[0014] Furthermore, the arc radius of the arc angle at the connection between the fin root and the heat pipe body is 5-8mm.

[0015] The beneficial effects of the utility model are as follows: the fins and the heat pipe body are integrally formed to form a heat pipe bundle, so that the tensile and bending performance of the heat pipe bundle is much higher than that of the existing welded fin heat pipe, and the stress resistance generated in the axial and radial directions is greatly improved. There is no need to reserve a large welding operation space between adjacent fins. The number of fins can be increased according to process calculations, the heat collection area can be increased, the fin height can be reduced, the damage to the pipe body caused by thermal alternation stress can be reduced, and the heat collection efficiency can be improved. The utility model sets stress release angles at both ends of the fin length direction, which can not only gradually release the stress generated between the fins and the heat pipe body to avoid stress concentration, but also reduce the thermal resistance when the heat collector is used at 650-700℃ and a flow rate of 2m / S, and reduce the wear of the heat catalyst on the heat pipe body and the fins.

[0016] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following preferred embodiments are specifically cited and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the cross-sectional structure of a heat pipe of a heat exchanger in the prior art.

[0018] Figure 2 It is a three-dimensional structural schematic diagram of an embodiment of the integrated heat extraction tube bundle of the utility model.

[0019] Figure 3 It is a front view structural schematic diagram of an embodiment of the integrated heat extraction tube bundle of the utility model.

[0020] Figure 4 yes Figure 3 AA section diagram in .

[0021] Description of reference numerals:

[0022] 1-heat pipe body, 11-end face, 2-fin, 21-stress release angle, 3-arc angle. DETAILED DESCRIPTION

[0023] The following is a further detailed description in conjunction with the accompanying drawings and preferred embodiments.

[0024] like Figures 2 to 4 The embodiment of the integrated heat extraction tube bundle of the utility model is shown, including a heat extraction tube body 1, wherein the outer wall of the heat extraction tube body 1 is integrally formed with a plurality of fins 2, the fins 2 extend along the axial direction of the heat extraction tube body 1, and the plurality of fins 2 are distributed in the circumferential direction of the heat extraction tube body 1, the fins 2 are perpendicular to the outer wall of the heat extraction tube body, and both ends of the fins 2 in the length direction are provided with stress release angles 21, so that the height of both ends of the fins gradually decreases in the direction close to the end face 11 corresponding to the heat extraction tube body 1, so that chamfers with unequal spacing are formed between the end face 11 and the fins 2, so that the stress release angles 21 at both ends of each fin are symmetrically distributed. Since the integrated heat extraction tube bundle designed by the utility model is normalized and tempered as a whole, no weld seam is generated, and thus no welding thermal stress is generated due to welding, so that the hardness of the root of the fin is the same as that of the fin itself and the heat extraction tube body 1, and the tensile and bending performance is much higher than that of the existing welded fin heat extraction tube, and the stress generated in the axial and radial directions is greatly improved. In this embodiment, the integrated heat extraction tube bundle can be formed by rolling, extrusion or machining, and its mechanical strength is much greater than that of the heat extraction tube with fins formed by welding, which increases the bending moment caused by the axial stress caused by the temperature gradient change from the surface to the root of the fin. In addition, since the fins and the heat extraction tube body 1 are formed as one piece, there is no need to reserve a large welding operation space between adjacent fins. The number of fins can be increased according to process calculations, the heat extraction area can be increased, the fin height can be reduced, the damage to the tube body caused by thermal alternation stress can be reduced, and the heat extraction efficiency can be improved.

[0025] Preferably, the slope of the stress release angle 21 is 1:10, but the present invention does not limit the specific value of the slope. The purpose of setting the stress release angle 21 is: (1) to gradually release the stress generated between the fins and the heat pipe body to avoid stress concentration; (2) to reduce the thermal resistance when the heat exchanger is used at 650-700°C and a flow rate of 2m / S, thereby reducing the wear of the heat catalyst on the heat pipe body and the fins.

[0026] Furthermore, the root of the fin 2 gradually narrows to the outer end (or head end) of the fin 2. The outer end of the fin 2 is the end of the fin that is radially away from the heat pipe body 1, and the root of the fin 2 is the end where the fin is connected to the heat pipe body, so that the cross section of the fin is a positive trapezoid. Specifically, according to the temperature change of the operating environment, the outer end and the root of the fin 2 produce a gradient change of 200-300°C. The axial stress generated by the different expansion is large, which further increases the radial stress of the pipeline. The fin is designed to be a positive trapezoidal cross-section with a narrower outer end and a wider root, which can reduce the axial stress intensity of the fin elongated due to high temperature. Preferably, the outer end of the fin 2 is transitioned by a chamfered arc angle 3, and the connection between the root of the fin and the heat pipe body is also transitioned by a chamfered arc angle 3. The arc radius of the two arc angles 3 is 2-4mm, or 5-8mm, respectively, which can effectively avoid the reduction of the resistance stress and thermal resistance caused by the existence of edges and corners. Specifically, the arc radius can be adaptively changed according to the actual working conditions.

[0027] In summary, the utility model designs an integrated heat extraction tube bundle based on the disadvantages of the existing fin structure and forming method, with the aim of reducing stress in all directions; the large amount of welding in traditional fins inevitably generates welding stress, and the axial non-uniform stress generated by the gradient change during use causes radial fracture of the fin tube (heat extraction tube bundle) or fracture due to axial weld fatigue.

[0028] The above description is only a preferred embodiment of the present invention, and the parts not described in detail are all prior art; any simple modification, equivalent changes and modifications made to the above embodiments by any technician familiar with the profession without departing from the scope of the technical solution of the present invention based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. An integrated heat extraction tube bundle, comprising a heat extraction tube body (1), characterized in that: The outer wall of the heat pipe body (1) is integrally formed with a plurality of fins (2), the fins (2) extending along the axial direction of the heat pipe body (1), the plurality of fins (2) being distributed circumferentially of the heat pipe body (1), and both ends of the fins (2) in the length direction are provided with stress release angles (21), so that the height of both ends of the fins gradually decreases in a direction approaching a corresponding end surface (11) of the heat pipe body (1).

2. The integrated heat extraction tube bundle according to claim 1 is characterized in that: The integrated heat extraction tube bundle is a heat extraction tube bundle formed by rolling, extrusion or machining.

3. The integrated heat extraction tube bundle according to claim 1 is characterized in that: The fins (2) are perpendicular to the outer wall of the heat extraction pipe body (1).

4. The integrated heat extraction tube bundle according to claim 1 is characterized in that: The slope of the stress relief angle (21) is 1:

10.

5. The integrated heat extraction tube bundle according to claim 1 is characterized in that: The fin (2) gradually narrows from the root to the outer end of the fin (2), and the outer end of the fin (2) is the end of the fin that is away from the heat pipe body (1) in the radial direction.

6. The integrated heat extraction tube bundle according to claim 5 is characterized in that: The cross section of the fin (2) is in the shape of a regular trapezoid.

7. The integrated heat extraction tube bundle according to claim 1 or 5, characterized in that: The outer end of the fin (2) is provided with a chamfered arc angle for transition.

8. The integrated heat extraction tube bundle according to claim 1 is characterized in that: A chamfered arc angle for transition is provided at the connection between the root of the fin (2) and the heat extraction pipe body.

9. The integrated heat extraction tube bundle according to claim 7, characterized in that: The arc radius of the arc angle at the outer end of the fin is 2-4 mm.

10. The integrated heat extraction tube bundle according to claim 8, characterized in that: The arc radius of the arc angle at the connection between the fin root and the heat pipe body is 5-8mm.

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