Fixed tube plate type heat exchanger

Abstract

The utility model relates to the technical field of heat exchange equipment, in particular to a fixed tube plate type heat exchanger which comprises a first tube box, a second tube box, a first tube plate, a second tube plate, a shell pass cylinder and a plurality of heat exchange tubes arranged in the shell pass cylinder, the first tube box, the second tube box, the first tube plate, the second tube plate and the shell pass cylinder are arranged on the two sides, and each heat exchange tube is provided with at least one flexible bending section. The flexible bending section at least comprises a first arc section and a second arc section which are oppositely arranged, and the axial rigidity of the heat exchange tube with the flexible bending section is far smaller than that of a straight tube, so that the temperature difference stress of the heat exchange tube and the shell pass cylinder can be greatly reduced, and the temperature difference stress of the heat exchange tube and the shell pass cylinder can be greatly reduced especially under the operation working conditions of large diameter and high shell pass pressure. The problem that the compensation effect is poor due to the adoption of an expansion joint is solved, so that the temperature difference compensation effect of the heat exchanger tube and shell pass is improved, the structure is simple, operation is reliable, the machining difficulty and the manufacturing cost are reduced, the service life of equipment is prolonged, and the equipment failure risk caused by the adoption of the expansion joint is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of heat exchange equipment, in particular to a fixed tube plate type heat exchanger. Background Art

[0002] Fixed tube sheet heat exchanger has the advantages of simple structure, easy manufacturing, reliable operation and convenient maintenance. Therefore, it is widely used in process assembly application fields such as petrochemical and energy production. It is widely used in industries such as petrochemical and energy production. This equipment is used for heat exchange between two materials at different temperatures.

[0003] The heat exchange tubes of the fixed tube sheet heat exchanger are straight tubes. The heat exchange tubes and the shell-side cylinder are fixed on the tube sheets at both ends. When the heat exchanger is running, the heat exchange tubes and the shell-side cylinder will produce axial temperature difference stress because of the temperature difference between the heat exchange tubes and the shell-side cylinder. When the temperature difference stress is greater than the allowable value of the heat exchange tubes or the shell-side cylinder, an expansion joint must be set on the shell-side cylinder for compensation.

[0004] However, if the diameter of the heat exchanger is large, or the shell pressure is relatively high, the expansion joint must be very thick in order to meet the strength requirements. The compensation effect of a wave expansion joint will be small, and several wave expansion joints will be needed. However, large-diameter thick-walled expansion joints not only have poor compensation effects, but are also very difficult to process and very expensive. In addition, due to the particularity of their structure, expansion joints are easily damaged after long-term operation.

[0005] The information disclosed in this background technology section is only intended to deepen the understanding of the overall background technology of the present invention, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to those skilled in the art. Utility Model Content

[0006] The utility model provides a fixed tube plate type heat exchanger, thereby effectively solving the problems in the background technology.

[0007] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is: a fixed tube sheet heat exchanger, comprising a first tube box and a second tube box on both sides and a shell-side cylinder in the middle, a plurality of heat exchange tubes arranged inside the shell-side cylinder and along the axial direction of the shell-side cylinder, and a first tube sheet and a second tube sheet arranged at both ends of the shell-side cylinder;

[0008] Both ends of each heat exchange tube are respectively inserted into the tube holes of the first tube sheet and the second tube sheet, and are connected with the first tube box and the second tube box. The shell-side cylinder is provided with a shell-side medium inlet and a shell-side medium outlet. The first tube box is provided with a tube-side medium inlet, and the second tube box is provided with a tube-side medium outlet.

[0009] The heat exchange tube is provided with at least one flexible bending section, and the flexible bending sections on each of the heat exchange tubes are arranged in parallel in sequence;

[0010] Each of the flexible curved sections divides the heat exchange tube into a first straight section and a second straight section, and the first straight section and the second straight section are arranged parallel to the axis of the shell-side cylinder;

[0011] The flexible curved segment at least includes two first arc segments and a second arc segment that are oppositely disposed. The first arc segment is disposed tangent to the first straight segment, and the second arc segment is disposed tangent to the second straight segment.

[0012] Furthermore, the flexible bending section includes two first arc sections and a second arc section arranged oppositely and a connecting section arranged between the first arc section and the second arc section. The connecting section is arranged at an angle, and both ends of the connecting section are arranged tangent to the first arc section and the second arc section.

[0013] Furthermore, each of the heat exchange tubes is provided with at least two of the flexible bending sections, and two adjacent flexible bending sections are symmetrically arranged to form a V-shaped structure.

[0014] Furthermore, each of the heat exchange tubes is provided with at least two of the flexible bending sections, and a third arc section is provided between two adjacent flexible bending sections to form a U-shaped structure.

[0015] Furthermore, each of the heat exchange tubes is provided with at least two of the flexible curved sections, and a third straight section is provided between two adjacent flexible curved sections.

[0016] Furthermore, the two flexible bending sections are symmetrically arranged to form a trapezoidal structure.

[0017] Furthermore, the two flexible bending sections are arranged in the same direction to form a stepped structure.

[0018] Further, the axes of the first straight segment, the second straight segment and the flexible curved segment are in the same plane.

[0019] Furthermore, the axes of the first straight segment, the second straight segment and the flexible curved segment are in at least two planes.

[0020] Furthermore, a plurality of the flexible bending sections are staggered in the same direction along the circumferential direction of the shell-side cylinder.

[0021] The beneficial effects of the utility model are as follows: by providing at least one flexible bending section on the heat exchange tube, the axial stiffness of the heat exchange tube with the flexible bending section is much smaller than the axial stiffness of the straight tube, thereby greatly reducing the temperature difference stress of the heat exchange tube and the shell cylinder, especially under operating conditions with large diameter and high shell pressure, the problem of poor compensation effect caused by the use of expansion joints is solved, thereby improving the temperature difference compensation effect of the shell and tube side of the heat exchanger, the structure is simple, the operation is reliable, the processing difficulty and manufacturing cost are reduced, the service life of the equipment is increased, and the risk of equipment failure caused by the use of expansion joints is avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 Schematic diagram of the structure of the fixed tube sheet heat exchanger in Example 1;

[0024] Figure 2 Schematic diagram of the structure of the fixed tube sheet heat exchanger in Example 1 (half of the first tube box, the second tube box and the shell-side cylinder are removed);

[0025] Figure 3 For Figure 2 A partial enlarged view of the middle A;

[0026] Figure 4 This is a structural schematic diagram of a specific implementation of the flexible bending section in Example 1;

[0027] Figure 5 This is a structural schematic diagram of another specific implementation of the flexible bending section in Example 1;

[0028] Figure 6 is a schematic structural diagram of the flexible bending section in Example 2;

[0029] Figure 7 is a schematic structural diagram of the flexible bending section in Example 3;

[0030] Figure 8 is a schematic structural diagram of the flexible bending section in Example 4;

[0031] Fig. 9 This is a schematic diagram of the structure of the flexible bending section in Example 5.

[0032] Figure numerals: 11, first pipe box; 111, tube-side medium inlet; 12, shell-side cylinder; 121, shell-side medium inlet; 122, shell-side medium outlet; 13, second pipe box; 131, tube-side medium outlet; 2, heat exchange tube; 21, first straight section; 22, second straight section; 23, flexible bending section; 231, first circular arc section; 232, second circular arc section; 233, third circular arc section; 234, connecting section; 235, third straight section; 3, first tube sheet; 4, support member; 5, second tube sheet. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0034] In the description of the present invention, it should be noted that the directions or positional relationships indicated by “center”, “up”, “down”, “left”, “right”, “vertical”, “horizontal”, “inside” and “outside”, etc., are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] Embodiment 1:

[0037] like Figures 1 to 5 As shown: a fixed tube sheet heat exchanger, comprising: a first tube box 11 and a second tube box 13 on both sides and a shell-side cylinder 12 in the middle, a plurality of heat exchange tubes 2 arranged inside the shell-side cylinder 12 and along the axial direction of the shell-side cylinder 12, and a first tube sheet 3 and a second tube sheet 5 arranged at both ends of the shell-side cylinder 12;

[0038] Both ends of each heat exchange tube 2 are respectively inserted into the tube holes of the first tube sheet 3 and the second tube sheet 5, and are connected with the first tube box 11 and the second tube box 13. The shell-side cylinder 12 is provided with a shell-side medium inlet 121 and a shell-side medium outlet 122. The first tube box 11 is provided with a tube-side medium inlet 111, and the second tube box 13 is provided with a tube-side medium outlet 131.

[0039] refer to Figure 1 , Figure 2 The heat exchange principle is as follows: the first medium enters the first tube box 11, the heat exchange tube 2, and the second tube box 13 in sequence from the tube-side medium inlet 111, and then flows out from the tube-side medium outlet 131; at the same time, the second medium enters the shell-side cylinder 12 from the shell-side medium inlet 121, and flows out from the shell-side medium outlet 122, so that the first medium inside the heat exchange tube 2 and the second medium outside the heat exchange tube 2 undergo heat exchange;

[0040] At least one flexible bending section 23 is provided on the heat exchange tube 2, and the flexible bending sections 23 on each heat exchange tube 2 are arranged in parallel in sequence;

[0041] Each flexible curved section 23 divides the heat exchange tube 2 into a first straight section 21 and a second straight section 22, and the first straight section 21 and the second straight section 22 are arranged parallel to the axis of the shell-side cylinder 12;

[0042] The flexible curved section 23 at least includes two first arc sections 231 and a second arc section 232 which are oppositely arranged. The first arc section 231 is arranged tangent to the first straight section 21 , and the second arc section 232 is arranged tangent to the second straight section 22 .

[0043] At least one flexible bending section 23 is provided on the heat exchange tube 2, and the flexible bending section 23 includes at least two first arc sections 231 and second arc sections 232 which are arranged oppositely. Since the axial stiffness of the heat exchange tube 2 with the flexible bending section 23 is much smaller than the axial stiffness of the straight tube, the temperature difference stress of the heat exchange tube 2 and the shell cylinder 12 can be greatly reduced, especially under the operating conditions of large diameter and high shell pressure, the problem of poor compensation effect caused by the use of expansion joints is solved, thereby improving the temperature difference compensation effect of the shell and tube side of the heat exchanger, the structure is simple, the operation is reliable, the processing difficulty and manufacturing cost are reduced, the service life of the equipment is increased, and the risk of equipment failure caused by the use of expansion joints is avoided.

[0044] In the embodiment, it also includes a support member 4 arranged in the shell-side cylinder 12 and used to support the heat exchange tube 2. The support member 4 can effectively prevent the heat exchange tube 2 from vibrating due to fluid flow during operation, reduce the impact and wear of the vibration on the heat exchange tube 2, and extend the service life of the heat exchange tube 2.

[0045] As a preferred embodiment of the above, a plurality of flexible bending sections 23 are staggered in the same direction along the circumference of the shell-side cylinder 12. Specifically, Figure 2 , 3As shown, on the one hand, the circumferentially staggered arrangement of the flexible bending sections 23 can arrange the heat exchange tubes 2 neatly in the internal space of the shell-side cylinder 12, maximize the use of space, and improve space utilization; on the other hand, the staggered arrangement of the flexible bending sections 23 can reduce the redundancy of the pipeline structure, making the overall structure more compact and reducing the volume and weight of the equipment.

[0046] like Figure 4 As shown, as a specific implementation of the flexible bending section 23, the flexible bending section 23 includes two first arc sections 231 and second arc sections 232 arranged oppositely, the first arc section 231 is connected to the first straight section 21, and the second arc section 232 is connected to the second straight section 22. In this way, the size of the flexible bending section 23 is small and the deformation degree is limited, so the following improvements are made:

[0047] like Figure 5 As shown, as another specific implementation of the flexible bending section 23, the flexible bending section 23 includes two first arc sections 231 and a second arc section 232 arranged oppositely and a connecting section 234 arranged between the first arc section 231 and the second arc section 232, and the connecting section 234 is inclined. Specifically, the angle between the connecting section 234 and the first arc section 231 is 100° to 150°, and the two ends of the connecting section 234 are tangent to the first arc section 231 and the second arc section 232. Specifically, the connecting section 234 in this manner is inclined so that the axes of the first straight section 21 and the second straight section 22 are not in a straight line. The connecting section 234 is inclined so that the entire heat exchange tube 2 system has higher flexibility and elasticity, can effectively disperse and reduce stress concentration caused by thermal expansion and contraction, avoid damage or failure of the heat exchange tube 2 caused by excessive local stress, and improve the reliability and durability of the equipment.

[0048] In this embodiment, as an implementation method of the heat exchange tube 2, the axes of the first straight section 21, the second straight section 22 and the flexible curved section 23 are in the same plane. Specifically, the axes of the first straight section 21, the second straight section 22 and the flexible curved section 23 are in the same plane, which simplifies the overall structural design and manufacturing process and reduces production costs.

[0049] As a preference of the above embodiment, as another implementation mode of the heat exchange tube 2, the axes of the first straight section 21, the second straight section 22 and the flexible curved section 23 are in at least two planes. Specifically, the axes of the first straight section 21, the second straight section 22 and the flexible curved section 23 are not in the same plane. The heat exchange tube 2 is bent and formed in different spaces. On the one hand, the heat exchange tube 2 has better flexibility and adaptability, provides a larger expansion space, effectively absorbs and compensates for the thermal expansion and contraction stress caused by temperature difference, and reduces damage to the pipeline. On the other hand, the axes of the flexible curved section 23 are designed in different planes to disperse the stress into different planes, reduce the possibility of stress concentration at a certain point, and improve the stability and safety of the pipeline.

[0050] Embodiment 2:

[0051] like Figure 6 As shown, different from Example 1, each heat exchange tube 2 is provided with at least two flexible bending sections 23, and two adjacent flexible bending sections 23 are symmetrically arranged to form a V-shaped structure. Specifically, since the two flexible bending sections 23 are symmetrically arranged to form a V-shaped structure, the two symmetrically arranged flexible bending sections 23 can evenly distribute stress during thermal expansion and reduce stress concentration; the stress generated by the heat exchange tube 2 during thermal expansion and contraction is dispersed to the two bending sections, avoiding stress concentration at one point, thereby reducing the risk of damage to the heat exchange tube 2 due to stress concentration;

[0052] Embodiment 3:

[0053] like Figure 7 As shown, different from Example 1, each heat exchange tube 2 is provided with at least two flexible bending sections 23, and a third arc section 233 is provided between two adjacent flexible bending sections 23 to form a U-shaped structure. Specifically, the U-shaped structure increases the flexibility and elasticity of the heat exchange tube 2, provides a larger expansion space, can effectively absorb and compensate for the thermal expansion and contraction stress caused by the temperature difference, can prevent the heat exchange tube 2 from rupture or deformation due to excessive temperature difference stress, and extend the service life of the equipment.

[0054] Embodiment 4:

[0055] like Figure 8 As shown, different from Example 1, each heat exchange tube 2 is provided with at least two flexible bending sections 23, a third straight section 235 is provided between two adjacent flexible bending sections 23, and the two flexible bending sections 23 are symmetrically arranged to form a trapezoidal structure. Specifically, the trapezoidal structure provides a larger expansion space through the symmetrically arranged flexible bending sections 23, which can more effectively absorb and compensate for the thermal expansion and contraction stress caused by the temperature difference, prevent the heat exchange tube 2 from being broken or deformed due to excessive temperature difference stress, and extend the service life of the equipment.

[0056] Embodiment 5:

[0057] like Figure 8 As shown, different from Example 1, each heat exchange tube 2 is provided with at least two flexible bending sections 23, a third straight section 235 is provided between two adjacent flexible bending sections 23, and the two flexible bending sections 23 are arranged in the same direction to form a stepped structure. Specifically, the stepped structure distributes the stress on a plurality of flexible bending sections 23, reduces the single-point stress concentration phenomenon, thereby improving the compensation effect of the heat exchanger, reducing the risk of breakage or damage of the heat exchange tube 2 due to excessive local stress, and improving the reliability and safety of the equipment.

[0058] In the above embodiment, the heat exchange tube with the flexible curved section 23 can be formed by bending a single tube, or by splicing the processed flexible curved section 23 with a straight section.

[0059] In the technical solution, the heat exchange tube is divided into a first straight section 21 and a second straight section 22, and the first straight section 21 and the second straight section 22 are arranged parallel to the axis of the shell cylinder 12. The so-called parallel arrangement here does not require strict parallelism, as long as it does not hinder the end of the heat exchange tube from passing through the tube hole of the tube sheet.

[0060] Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the description are only for explaining the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which are within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A fixed tube sheet heat exchanger, characterized in that: It includes a first tube box and a second tube box on both sides and a shell-side cylinder in the middle, a plurality of heat exchange tubes arranged inside the shell-side cylinder and along the axial direction of the shell-side cylinder, and a first tube sheet and a second tube sheet arranged at both ends of the shell-side cylinder; Both ends of each heat exchange tube are respectively inserted into the tube holes of the first tube sheet and the second tube sheet, and are connected with the first tube box and the second tube box. The shell-side cylinder is provided with a shell-side medium inlet and a shell-side medium outlet. The first tube box is provided with a tube-side medium inlet, and the second tube box is provided with a tube-side medium outlet. The heat exchange tube is provided with at least one flexible bending section, and the flexible bending sections on each of the heat exchange tubes are arranged in parallel in sequence; Each of the flexible curved sections divides the heat exchange tube into a first straight section and a second straight section, and the first straight section and the second straight section are arranged parallel to the axis of the shell-side cylinder; The flexible curved segment at least comprises two first arc segments and a second arc segment which are arranged opposite to each other, and a connecting segment which is arranged between the first arc segment and the second arc segment, wherein the connecting segment is arranged obliquely, the first arc segment is arranged tangent to the first straight segment, and the second arc segment is arranged tangent to the second straight segment; The plurality of flexible bending sections are staggered in the same direction along the circumferential direction of the shell-side cylinder.

2. The fixed tube plate heat exchanger according to claim 1, characterized in that: Each of the heat exchange tubes is provided with at least two flexible bending sections, and two adjacent flexible bending sections are symmetrically arranged to form a V-shaped structure.

3. The fixed tube plate heat exchanger according to claim 1, characterized in that: Each of the heat exchange tubes is provided with at least two flexible curved sections, and a third straight section is provided between two adjacent flexible curved sections.

4. The fixed tube plate heat exchanger according to claim 3, characterized in that: The two flexible bending sections are symmetrically arranged to form a trapezoidal structure.

5. The fixed tube plate heat exchanger according to claim 3, characterized in that: The two flexible bending sections are arranged in the same direction to form a stepped structure.

6. The fixed tube sheet heat exchanger according to claim 1, characterized in that: The axes of the first straight segment, the second straight segment and the flexible curved segment are in a plane.

7. The fixed tube plate heat exchanger according to claim 1, characterized in that: The axes of the first straight segment, the second straight segment and the flexible curved segment are in at least two planes.

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