Leak-proof double tube sheet heat exchanger

Abstract

This invention provides a leak-proof double tubesheet heat exchanger, belonging to the technical field of heat exchange equipment. It includes a heat exchange cylinder and two sets of tubesheet assemblies disposed within the heat exchange cylinder. Each tubesheet assembly includes a tube-side tubesheet, a shell-side tubesheet, a separator, and an on / off valve. The tube-side tubesheet is disposed within the heat exchange cylinder, and is located close to the tube-side region. The shell-side tubesheet is also disposed within the heat exchange cylinder, forming an isolation cavity between the two tubesheets, with the shell-side tubesheet located on the side closer to the shell-side region. The separator is disposed within the isolation cavity, dividing it into a buffer zone and a detection zone. The detection zone is under negative pressure. The separator is connected to an external drain pipe for communication with the outside. This leak-proof double tubesheet heat exchanger aims to solve the problem in existing double tubesheet heat exchangers where leaks are difficult to completely drain, and residual media continue to corrode the tubesheet, leading to a reduced service life of the heat exchanger.

Description

Technical Field

[0001] This utility model belongs to the technical field of heat exchange equipment, and more specifically, it relates to a leak-proof double tube sheet heat exchanger. Background Technology

[0002] Double tube sheet heat exchangers are specialized heat exchange equipment widely used in industries such as chemical, pharmaceutical, and food processing. Their core feature is the presence of two independent tube sheets at both ends of the heat exchange tubes, forming a closed isolation chamber between them. The main purpose of this design is to establish a double sealing barrier between the tube side and the shell side. If a leak occurs on one side, the medium will enter the isolation chamber and be discharged through the external drain pipe or trigger an alarm, thus preventing direct mixing of different media and avoiding contamination or safety accidents.

[0003] However, in traditional double tubesheet heat exchangers, micro-leakage can easily occur at the tubesheet joints due to vibration fatigue or corrosion during long-term operation. The static seal of the double tubesheet structure alone cannot ensure long-term reliable sealing performance. If the medium leaks into the space between the two tubesheets, it is difficult to completely remove the medium using only the discharge pipe, and the remaining medium will continue to corrode the tubesheets, leading to a reduction in the service life of the entire heat exchanger. Utility Model Content

[0004] The purpose of this invention is to provide a leak-proof double tube sheet heat exchanger, which aims to solve the problem that existing double tube sheet heat exchangers are difficult to completely drain after leakage, and the residual medium continues to corrode the tube sheet, resulting in a reduction in the service life of the heat exchanger.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] A leak-proof double tubesheet heat exchanger is provided, comprising a heat exchange cylinder and two sets of tubesheet assemblies disposed within the heat exchange cylinder, and further comprising heat exchange tubes disposed within the heat exchange cylinder. The two sets of tubesheet assemblies divide the interior of the heat exchange cylinder into a shell-side region and a tube-side region located on opposite sides of the shell-side region along a first path; the tubesheet assembly includes:

[0007] A tube sheet is disposed inside the heat exchange cylinder, and the tube sheet is close to the tube side region;

[0008] A shell-side tube sheet is disposed inside the heat exchange cylinder and is spaced apart from the tube-side tube sheet along the first path. An isolation cavity is formed between the shell-side tube sheet and the tube-side tube sheet, and the shell-side tube sheet is located on the side closer to the shell-side region.

[0009] A separator cylinder is disposed within the isolation chamber, dividing the isolation chamber into a buffer zone and a detection zone. The inner ring of the separator cylinder forms the buffer zone, and the detection zone is formed between the separator cylinder and the heat exchange cylinder. The detection zone is under negative pressure. The separator cylinder is connected to an external drain pipe for communication with the outside.

[0010] A switching valve is located on the external discharge pipe.

[0011] In one possible implementation, the leak-proof double tube sheet heat exchanger further includes a pressure detector located in the detection zone, and a controller and an alarm connected to the pressure detector, the alarm being used to issue an audible or visual alarm.

[0012] In one possible implementation, the switching valve is communicatively connected to the controller.

[0013] In one possible implementation, the leak-proof double tube sheet heat exchanger is connected to a drain pipe of the buffer zone and a control valve located on the drain pipe, the drain pipe being used to discharge the medium in the buffer zone.

[0014] In one possible implementation, the leak-proof dual tube sheet heat exchanger further includes a pressure sensor located in the buffer zone, and the pressure sensor and the control valve are respectively communicatively connected to the controller.

[0015] In one possible implementation, the leak-proof dual tube sheet heat exchanger further includes a vacuum pump connected to the detection zone, the vacuum pump being communicatively connected to the controller to maintain the detection zone under negative pressure.

[0016] In one possible implementation, the leak-proof double tube sheet heat exchanger further includes a Venturi effect enhancer disposed on the external discharge tube, the Venturi effect enhancer being used to completely discharge the medium in the detection zone.

[0017] In one possible implementation, the leak-proof double tube sheet heat exchanger further includes a fixed flange fitted over the heat exchange cylinder. The fixed flange is connected to the tube sheet and seals the area between the tube sheet and the heat exchange cylinder. The fixed flange is used to fix the tube sheet.

[0018] In one possible implementation, the fixed flange is located on the outside of the tube side region and has a first fixing hole. The tube side plate has a mounting part located outside the heat exchange cylinder. The mounting part has a second fixing hole corresponding to the first fixing hole. Fixing members are inserted into the first fixing hole and the second fixing hole.

[0019] The advantages of this leak-proof double tube sheet heat exchanger are as follows: Compared with the prior art, by setting a partition cylinder in the isolation chamber, dividing the isolation chamber into a buffer zone and a detection zone, when a leak occurs in the tube side or shell side, the leaking medium first enters the buffer zone and is quickly discharged through the external drain pipe under negative pressure. This effectively avoids the continuous corrosion problem caused by medium residue in traditional structures and significantly extends the service life of the heat exchanger. This application adopts a double sealing barrier and physical isolation structure. Compared with the traditional single-layer isolation structure, the negative pressure design can reduce the residence time of the medium in the buffer zone and discharge it in a timely manner through the external drain pipe, improving safety performance. Furthermore, the scheme of dividing the isolation chamber into a buffer zone and a detection zone also increases the overall structural strength and extends the service life of the heat exchanger. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A schematic diagram of the structure of the leak-proof double tube sheet heat exchanger provided in this embodiment of the utility model;

[0022] Figure 2 for Figure 1 A magnified view of part A in the middle.

[0023] In the diagram: 1. Heat exchanger tube; 101. Shell side region; 102. Tube side region; 2. Tube side tube sheet; 201. Buffer zone; 202. Detection zone; 3. Shell side tube sheet; 4. Divider tube; 5. Fixed flange; 6. External drain pipe; 7. Drain pipe; 8. Heat exchanger tube. Detailed Implementation

[0024] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0025] In the claims, description, and accompanying drawings of this utility model, unless otherwise expressly defined, the terms "first," "second," or "third," etc., are used to distinguish different objects, not to describe a specific order. Unless otherwise stated, other directional terms, such as "vertical," "clockwise," and "counterclockwise," indicate orientation or positional relationships based on the orientation and positional relationships shown in the accompanying drawings, and are only for the convenience of describing the utility model and simplifying the description, not to indicate or imply that the referred device or element must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the specific scope of protection of this utility model. In the claims, description, and accompanying drawings of this utility model, unless otherwise expressly defined, the terms "fixed connection" or "fixed connection" should be interpreted broadly, that is, any connection method in which there is no displacement relationship or relative rotation relationship between the two, that is, including non-removable fixed connection, detachable fixed connection, integral connection, and fixed connection through other devices or elements. In the claims, description, and accompanying drawings of this utility model, the terms "comprising," "having," and their variations are intended to mean "including but not limited to."

[0026] Please refer to the following: Figures 1 to 2 The leak-proof double tube sheet heat exchanger provided by this utility model will now be described. The leak-proof double tube sheet heat exchanger includes a heat exchange cylinder 1 and two sets of tube sheet assemblies disposed within the heat exchange cylinder 1, and also includes heat exchange tubes 10 disposed within the heat exchange cylinder 1. The two sets of tube sheet assemblies divide the interior of the heat exchange cylinder 1 into a shell-side region 101 and a tube-side region 102 located on opposite sides of the shell-side region 101 along a first path. The tube sheet assembly includes a tube-side tube sheet 2, a shell-side tube sheet 3, a partition cylinder 4, and an on / off valve. The tube-side tube sheet 2 is disposed within the heat exchange cylinder 1 and is close to the tube-side region 102; the shell-side tube sheet 3 is disposed within the heat exchange cylinder 1 and... The shell-side tube sheet 3 and the tube-side tube sheet 2 are spaced apart along the first path, forming an isolation cavity between them, with the shell-side tube sheet 3 located on the side closer to the shell-side region 101; the partition cylinder 4 is located in the isolation cavity and divides the isolation cavity into a buffer zone 201 and a detection zone 202. The inner ring of the partition cylinder 4 forms the buffer zone 201, and the partition cylinder 4 and the heat exchange cylinder 1 form the detection zone 202. The detection zone 202 is under negative pressure. The partition cylinder 4 is connected to an external drain pipe 6 for communication with the outside; a switch valve is located on the external drain pipe 6.

[0027] The leak-proof double tube sheet heat exchanger provided by this utility model, compared with the prior art, divides the isolation chamber into a buffer zone 201 and a detection zone 202 by setting a partition cylinder 4 inside the isolation chamber. When a leak occurs in the tube side 102 or the shell side, the leaking medium first enters the buffer zone 201 and is quickly discharged through the external drain pipe 6 under negative pressure. This effectively avoids the problem of continuous corrosion caused by medium residue in traditional structures and significantly extends the service life of the heat exchanger. This application adopts a double sealing barrier and physical isolation structure. Compared with the traditional single-layer isolation structure, the negative pressure design can reduce the residence time of the medium in the buffer zone 201 and discharge it in time through the external drain pipe 6, improving safety performance. In addition, the scheme of dividing the isolation chamber into the buffer zone 201 and the detection zone 202 also increases the overall structural strength and extends the service life of the heat exchanger.

[0028] It should be noted that the tube side and shell side each have an inlet and an outlet connected to the outside, facilitating the entry and exit of the medium. The heat exchange tubes 10 pass through the tube sheet 2 and the shell sheet 3, and extend into the entire inner cavity of the heat exchange cylinder 1. Since the above features are prior art and not the innovation of this application, they will not be described in detail further.

[0029] Optionally, the pressure range of the detection zone 202 is -0.01 to 0.05 MPa.

[0030] In some embodiments, the leak-proof dual tube sheet heat exchanger further includes a pressure detector located in the detection zone 202, and a controller and an alarm connected to the pressure detector, the alarm being used to issue an audible or visual alarm.

[0031] When the pressure detector detects an abnormal pressure in detection zone 202, it generates an alarm signal. The controller then activates the alarm based on this signal, enabling operators to detect leaks immediately and take appropriate measures, significantly improving the equipment's safety protection level. This intelligent monitoring system works in conjunction with the existing negative pressure venting mechanism to form a closed-loop protection system of "detection-alarm-venting." This not only effectively solves the problem of delayed leak detection in traditional heat exchangers but also provides a basis for preventative maintenance through accurate pressure data recording, further reducing the risk of equipment damage caused by leaks.

[0032] In some embodiments, the switching valve is communicatively connected to the controller.

[0033] When the controller receives an alarm signal from the pressure detector, it simultaneously activates the alarm and opens the valve to discharge the medium from detection zone 202. This automatic drainage system, working in conjunction with pressure monitoring and audible / visual alarm functions, effectively avoids the response delays caused by manual operation in traditional equipment. It significantly reduces the risk of safety accidents caused by leaks, while precise valve control minimizes medium loss, improving the stability and economy of the process system.

[0034] In some embodiments, please refer to Figure 1 and Figure 2 The leak-proof double tube sheet heat exchanger is connected to the drain pipe 7 of the buffer zone 201 and the control valve on the drain pipe 7. The drain pipe 7 is used to discharge the medium in the buffer zone 201.

[0035] When a large amount of media leaks, relying solely on the media entering the detection zone 202 before discharge may result in a large amount of media remaining in the buffer zone 201, potentially causing safety hazards. This embodiment connects the buffer zone 201 to the outside via a drain pipe 7. In the event of a large media leak, the media in both the buffer zone 201 and the detection zone 202 can be discharged simultaneously via the drain port, reducing the risk of safety accidents caused by media leakage.

[0036] In some embodiments, the leak-proof dual tube sheet heat exchanger also includes a pressure sensor located in the buffer zone 201, and the pressure sensor and the control valve are respectively communicatively connected to the controller.

[0037] The pressure sensor monitors the pressure in the buffer zone 201 in real time. When the pressure in the buffer zone 201 is abnormal, the pressure sensor generates an abnormal pressure signal. The controller controls the control valve to open according to the abnormal pressure signal, and discharges the medium in the detection zone 202 through the drain pipe 7.

[0038] Optionally, the controller in this embodiment can be the same controller as the controller that controls the pressure detector, or they can be set separately.

[0039] In some embodiments, the leak-proof dual tube sheet heat exchanger further includes a vacuum pump connected to the detection zone 202, the vacuum pump being communicatively connected to the controller to maintain the detection zone 202 under negative pressure.

[0040] The vacuum pump ensures that the detection zone 202 remains under negative pressure. In the event of a leak, the negative pressure environment quickly draws the leaking medium into the detection zone 202, which is then discharged through a drain port, preventing the medium from accumulating inside and effectively preventing the leaking medium from spreading to the shell-side region 101 or the tube-side region 102, greatly reducing the risk of cross-contamination. Simultaneously, the stable negative pressure helps improve the sensitivity of the leak detection device, enabling the detection system to detect leak signs more quickly and providing more time for timely troubleshooting. Furthermore, the controller can intelligently regulate the vacuum pump, dynamically adjusting the pressure in the detection zone 202 according to the actual operating conditions of the heat exchanger. This ensures effective leak protection while reducing equipment energy consumption and improving the system's economy and reliability.

[0041] In some embodiments, please refer to Figure 1The leak-proof double tube sheet heat exchanger also includes a Venturi effect enhancer installed on the external drain pipe 6, which is used to completely drain the medium in the detection zone 202.

[0042] The Venturi effect enhancer, through a special converging-expanding pipe structure, accelerates the flow velocity of the medium passing through the external discharge pipe 6, thereby creating a local negative pressure within the detection zone 202. This negative pressure not only actively extracts trace amounts of leaked medium remaining in the corners and gaps of the detection zone 202, but also accelerates the discharge process, improving discharge efficiency and ensuring that the medium within the detection zone 202 is completely discharged. Furthermore, the Venturi effect enhancer requires no additional power, relying solely on the medium's own pressure to achieve efficient drainage. This reduces energy consumption, lowers equipment maintenance costs and complexity, and ensures the long-term stable operation of the leak prevention system.

[0043] It should be noted that a Venturi effect enhancer is a fluid dynamics device designed based on the Venturi tube principle. It is used to enhance the Venturi effect, thereby optimizing processes such as fluid transport, mixing, suction, or pressure regulation. Its core objective is to increase fluid velocity, enhance negative pressure suction capacity, or improve energy transfer efficiency.

[0044] In some embodiments, please refer to Figure 1 The leak-proof double tube sheet heat exchanger also includes a fixed flange 5 fitted outside the heat exchange cylinder 1. The fixed flange 5 is connected to the tube sheet 2 and seals the area between the tube sheet 2 and the heat exchange cylinder 1. The fixed flange 5 is used to fix the tube sheet 2.

[0045] The tube sheet 2 is connected to the fixed flange 5, which further enhances the stability of the tube sheet 2 and prevents it from deforming or displacing under pressure impact. At the same time, the fixed flange 5 makes axial contact with the tube sheet 2, thereby sealing the gap between the tube sheet 2 and the heat exchange cylinder 1 and improving the overall sealing performance.

[0046] In some embodiments, please refer to Figure 1 The fixed flange 5 is located on the outside of the tube side area 102 and has a first fixing hole. The tube side plate 2 has a mounting part located outside the heat exchange cylinder 1. The mounting part has a second fixing hole corresponding to the first fixing hole. Fixing members are inserted into the first fixing hole and the second fixing hole.

[0047] The fastener passes through the first and second fixing holes, tightly connecting the fixing flange 5 to the tube sheet 2 to form a rigid connection structure. This structure effectively resists vibration, pressure fluctuations, and thermal expansion stress during heat exchanger operation, preventing the tube sheet 2 from loosening or shifting, ensuring the stability of the internal heat exchange tube array 10, and maintaining high-efficiency heat exchange performance. The tightly connected fixing flange 5 and tube sheet 2, together with the sealing structure, effectively seal any potential leakage channels on the outside of the tube side region 102, preventing media leakage and blocking the intrusion of external contaminants, thus ensuring the safe and stable operation of the equipment.

[0048] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A leak-proof double tube sheet heat exchanger, characterized in that, The system includes a heat exchange cylinder and two sets of tube sheet assemblies disposed within the heat exchange cylinder, and further includes heat exchange tubes disposed within the heat exchange cylinder. The two sets of tube sheet assemblies divide the interior of the heat exchange cylinder into a shell-side region and a tube-side region located on opposite sides of the shell-side region along a first path. The tube sheet assembly includes: A tube sheet is disposed inside the heat exchange cylinder, and the tube sheet is close to the tube side region; A shell-side tube sheet is disposed inside the heat exchange cylinder and is spaced apart from the tube-side tube sheet along the first path. An isolation cavity is formed between the shell-side tube sheet and the tube-side tube sheet, and the shell-side tube sheet is located on the side closer to the shell-side region. A separator cylinder is disposed within the isolation chamber, dividing the isolation chamber into a buffer zone and a detection zone. The inner ring of the separator cylinder forms the buffer zone, and the detection zone is formed between the separator cylinder and the heat exchange cylinder. The detection zone is under negative pressure. The separator cylinder is connected to an external drain pipe for communication with the outside. A switching valve is located on the external discharge pipe.

2. The leak-proof double tube sheet heat exchanger as described in claim 1, characterized in that, The leak-proof double tube sheet heat exchanger also includes a pressure detector located in the detection zone, and a controller and an alarm connected to the pressure detector. The alarm is used to issue an audible or visual alarm.

3. The leak-proof double tube sheet heat exchanger as described in claim 2, characterized in that, The switching valve is communicatively connected to the controller.

4. The leak-proof double tube sheet heat exchanger as described in claim 1, characterized in that, The leak-proof double tube sheet heat exchanger is connected to the drain pipe of the buffer zone and the control valve located on the drain pipe. The drain pipe is used to discharge the medium in the buffer zone.

5. The leak-proof double tube sheet heat exchanger as described in claim 4, characterized in that, The leak-proof double tube sheet heat exchanger also includes a pressure sensor located in the buffer zone, and the pressure sensor and the control valve are respectively connected to the controller.

6. The leak-proof double tube sheet heat exchanger as described in claim 2, characterized in that, The leak-proof double tube sheet heat exchanger also includes a vacuum pump connected to the detection zone. The vacuum pump is communicatively connected to the controller and is used to maintain the detection zone under negative pressure.

7. The leak-proof double tube sheet heat exchanger as described in claim 1, characterized in that, The leak-proof double tube sheet heat exchanger also includes a Venturi effect enhancer installed on the external exhaust tube, which is used to completely discharge the medium in the detection zone.

8. The leak-proof double tube sheet heat exchanger as described in claim 1, characterized in that, The leak-proof double tube sheet heat exchanger also includes a fixed flange sleeved outside the heat exchange cylinder. The fixed flange is connected to the tube sheet and seals the area between the tube sheet and the heat exchange cylinder. The fixed flange is used to fix the tube sheet.

9. The leak-proof double tube sheet heat exchanger as described in claim 8, characterized in that, The fixed flange is located on the outside of the tube side area and has a first fixing hole. The tube side plate has a mounting part located outside the heat exchange cylinder. The mounting part has a second fixing hole corresponding to the first fixing hole. Fixing members are inserted into the first fixing hole and the second fixing hole.

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