A method for treating external leakage of MGGH tube bundle heat exchanger

Abstract

The present application relates to heat exchanger leakage technical field, especially suitable for MGGH tube bundle heat exchanger external leakage treatment method, single heat exchange tube plugging isolation: according to the on-line water injection leak detection to find the broken, U-shaped heat exchange tube one end, and according to the layout to find the other end of the pipe corresponding, then the plug is used to block the two ends of the heat exchange tube, that is, a heat exchange tube with a leak point; Multiple heat exchange tube header isolation: first, the plurality of heat exchange tubes are all blocked by the method, then the water outlet pipeline is moved from the inlet and outlet water semicircular header to the delivery semicircular header, and the original water outlet pipeline is blocked, welded and sealed by blind plate, realizing the header plugging isolation. The method is suitable for MGGH tube bundle heat exchanger external leakage treatment, the plugging isolation method can be installed and disassembled in different areas, without the need for integral installation and disassembly, so that the installation and disassembly engineering quantity is small, the treatment efficiency is high, and the equipment utilization rate is high.

Description

Technical Field

[0001] This invention relates to the field of heat exchanger leakage technology, and in particular to a method for treating external leaks in MGGH tube bundle heat exchangers. Background Technology

[0002] A heat exchanger is a device that transfers part of the heat from a hot fluid to a cold fluid; it is also called a heat exchanger. Heat exchangers play an important role in chemical, petroleum, power, food, and many other industrial production processes. In chemical production, heat exchangers can be used as heaters, coolers, condensers, evaporators, and reboilers, and are widely used. Among them, the mixing heat exchanger relies on the direct contact between cold and hot fluids for heat transfer. This heat transfer method avoids the thermal resistance of fouling on the heat transfer walls and their sides. As long as the contact between the fluids is good, there is a large heat transfer rate.

[0003] Currently, the MGGH tube bundle heat exchanger uses a large, integrated manifold at the ends of the heat exchange tubes, with only inlet and outlet areas. For example, in the novel U-shaped tube bundle heat exchanger disclosed in existing technology CN103424011 A, if a leak is detected in one or more heat exchange tubes, the entire manifold needs to be dismantled and reinstalled. This involves a large amount of dismantling and installation work, and requires a long downtime for equipment maintenance, affecting normal operation. Summary of the Invention

[0004] The main objective of this invention is to overcome the shortcomings of existing technologies and provide a method for handling external leakage in MGGH tube bundle heat exchangers. This sealing and isolation method allows for zoned installation and disassembly, eliminating the need for complete assembly installation and disassembly. This results in a smaller workload for installation and disassembly, higher processing efficiency, and eliminates the need for prolonged unit downtime, thus maximizing equipment utilization.

[0005] The technical solution adopted by this invention to achieve its technical objective is: a method for treating external leakage in MGGH tube bundle heat exchangers, specifically comprising the following steps:

[0006] S1. Each module of the MGGH tube bundle heat exchanger is equipped with five semi-circular headers, wherein:

[0007] The inlet and outlet ends are equipped with semi-circular inlet and outlet headers with small radii, which are internally connected to two heat exchange tubes;

[0008] The middle conveying end is equipped with a semi-circular conveying header with a large radius, which is internally connected to four heat exchange tubes;

[0009] S2. Water is injected into the semi-circular header at one end through the inlet pipe, flows through the heat exchange pipe into the conveying semi-circular header, mixes, and finally flows into the semi-circular header at the other end, and is discharged through the outlet pipe, thereby achieving heat exchange.

[0010] S3. When a single heat exchange tube leaks, use a single heat exchange tube to seal and isolate it: Locate one end of the damaged, U-shaped heat exchange tube based on online water injection leak detection, and find the corresponding other end of the tube according to the layout diagram. Then, use plugs to seal both ends of the heat exchange tube (i.e., for a heat exchange tube with a leak, plug one pipe opening in each of the two corresponding headers at the top), and seal it completely with electric welding.

[0011] S4. When multiple heat exchange tubes are leaking, use a multi-heat exchange tube header for isolation: First, seal all the leaking heat exchange tubes using the method in step S3, for example, heat exchange tubes 101, 2, 3, and 4.

[0012] Then, the water outlet pipe is moved from the inlet / outlet semi-circular header to the conveying semi-circular header, and the original water outlet pipe is sealed by welding with a blind flange.

[0013] After sealing, the inlet pipe remains unchanged, but the outlet pipe is changed. The outlet pipe is changed from heat exchange pipes No. 1 and No. 2 to heat exchange pipes No. 5 and No. 6, thus achieving the sealing and isolation of the manifold.

[0014] Preferably, the radius of the conveying semi-circular header is larger than the radius of the inlet / outlet semi-circular header.

[0015] Preferably, the plug in step S3 is a solid structure or an airbag structure with concentric shafts and large and small ends.

[0016] Preferably, the airbag structure includes an inflatable baffle, an inflatable capsule, an air tube, a sealing tube, an air pump, and a through-slot;

[0017] One side of the inflatable baffle is fixedly connected to the inflatable capsule. After the inflatable capsule is inflated through the air pipe, it pushes against the inside of the heat exchange tube. The inflatable capsule is designed to resemble a threaded structure, blocking the inside of the heat exchange tube. At this time, the inflatable baffle is inflated and covers the end face of the heat exchange tube, thus having a dual blocking effect with the inflatable capsule.

[0018] Preferably, one end of the air tube is fixedly connected to the inflation baffle, and the other end passes through a semi-circular header and is connected to the air pump via an inflation nozzle. The air pump inflates the air tube, inflation baffle, and inflation capsule. A pressure gauge is installed on the air pump tube to facilitate control of the air pressure inside the inflation baffle and inflation capsule. Furthermore, the inflation nozzle at the other end of the air tube prevents gas from automatically escaping after inflation, similar to the principle of a tire inflator.

[0019] Preferably, the semi-circular header has a corresponding through groove to accommodate the sealing tube. The radius of the through groove is larger than the radius of the air pipe. After the uninflated inflation baffle and inflation capsule are placed into the semi-circular header through the through groove, the inflation baffle and inflation capsule are partially inflated. The partially inflated inflation capsule is placed inside the port of the heat exchange tube, and the inflation baffle covers the end face of the port of the heat exchange tube. Finally, the air pump is used to fully inflate the tube and seal the end of the heat exchange tube.

[0020] Preferably, the sealing tube is sleeved on the outer wall of the trachea and welded to the inside of the through groove. The sealing tube starts from the top of the trachea, sleeved on the outer wall of the trachea and simultaneously in contact with the inner wall of the through groove 605.

[0021] The sealing tube and the air tube slide relative to each other, and sealing rings are provided at both ends inside to keep them sealed. By sliding the air tube up and down, the inflation baffle and inflation capsule can be pressed down periodically to prevent them from falling out of the heat exchange tube.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: the method for handling external leakage of MGGH header-type tube bundle heat exchanger is provided with a semi-circular header at the tube end of the heat exchange tube and divided into five header areas. The five header areas are interconnected with the tube end of the heat exchange tube to achieve heat exchange. Different treatment methods are adopted according to the number of heat exchange tube leaks. When the number of heat exchange tube leaks is small, a solid plug is used to seal and isolate a single heat exchange tube. When the number of heat exchange tube leaks is large, the header corresponding to the area is isolated as a whole.

[0023] Whether using single heat exchange tube blocking or multiple heat exchange tube blocking and header isolation methods, this blocking and isolation method allows for regional disassembly and installation without the need for disassembly and installation of the entire large header. This results in a smaller workload for disassembly and installation, higher processing efficiency, and no need for long-term unit shutdown for maintenance, thus maximizing equipment utilization.

[0024] Furthermore, this method for handling external leakage in MGGH header-type tube bundle heat exchangers can also be used for header installation without disassembly, making it more convenient. By setting the plug as an airbag structure, a corresponding through groove is opened inside the semi-circular header. After the uninflated inflation baffle and inflation bladder are placed into the heat exchange tube through the through groove via the conveying semi-circular header, the tube is fully inflated by an air pump to block the end of the heat exchange tube. The sealing tube and the air tube maintain relative sliding, and sealing rings are set at both ends inside to keep them sealed. The sealing tube is then welded inside the through groove to maintain the seal. Attached Figure Description

[0025] Figure 1 A schematic diagram of the main sectional view of a single heat exchange tube being sealed and isolated.

[0026] Figure 2 A schematic diagram of the main sectional view of the structure for header isolation of multiple heat exchange tubes.

[0027] Figure 3 This is a schematic diagram of the main cross-sectional view of the airbag structure installed inside the heat exchange tube.

[0028] Figure 4 This is a schematic diagram of the front view of the airbag structure.

[0029] in:

[0030] 1-Heater body; 101-Heat exchange tube; 2-Plug; 3-Semi-circular header; 301-Inlet / outlet semi-circular header; 302-Conveying semi-circular header; 4-Inlet pipe; 5-Outlet pipe; 6-Inflating baffle; 601-Inflating capsule; 602-Air pipe; 603-Sealing pipe; 604-Air pump; 605-Through groove. Implementation

[0031] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0032] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention. Example

[0034] Please see Figure 1-2A method for handling external leakage in MGGH tube bundle heat exchangers, specifically comprising the following steps:

[0035] S1, MGGH tube bundle heat exchanger: each module is equipped with five semi-circular headers 3, of which the inlet and outlet water ends are equipped with smaller inlet and outlet semi-circular headers 301, which are internally connected to two heat exchange tubes;

[0036] The intermediate conveying end is equipped with a semi-circular conveying header 302 with a large radius, which is internally connected to four heat exchange tubes;

[0037] The radius of the semi-circular conveying header 302 is larger than the radius of the inlet / outlet semi-circular header 301.

[0038] S2. Water is injected into the semi-circular header 301 at one end through the water inlet pipe 4. After being mixed in the conveying semi-circular header 302 through the heat exchange pipe 101, the water finally flows into the semi-circular header 301 at the other end and is discharged through the water outlet pipe 5, thereby achieving heat exchange.

[0039] S3. When a single heat exchange tube 101 leaks, a single heat exchange tube 101 is sealed and isolated: the single heat exchange tube sealing and isolation means only sealing the leaking heat exchange tube. The sealing position is the end face of the leaking heat exchange tube in the header, rather than the specific leak point in the flue, so as to achieve online isolation treatment. The sealing material is the plug 2, and the plug 2 is set as a solid structure with a concentric shaft and a large and small head.

[0040] The damaged U-shaped heat exchange tube 101 was located by online water injection and leak detection. The other end of the tube was located according to the layout diagram. Then, the two ends of the heat exchange tube 101 were sealed with plug 2 (i.e., for a heat exchange tube with a leak, one pipe opening was blocked in each of the two corresponding headers on the top, i.e., for a heat exchange tube with a leak). The tube was then fully sealed with electric welding.

[0041] S4. When multiple heat exchanger tubes 101 leak externally, multiple heat exchanger tube headers should be used for isolation:

[0042] S4. When multiple heat exchange tubes 101 leak, use a multi-heat exchange tube header for isolation: Based on the on-site leakage situation, it was found that the number of leaking heat exchange tubes on the windward side was much greater than that on the leeward side. For example, the leakage probability of heat exchange tubes 1, 2, 3, and 4 in the figure is greater than that of heat exchange tubes 13, 14, 15, and 16. When the leakage rate of heat exchange tubes 1, 2, 3, and 4 reaches a high proportion, and the water supply system cannot maintain the stable operation of the heater, the header isolation method can be used.

[0043] First, all heat exchange tubes 101, 1, 2, 3, and 4, are sealed using the method described in step S3;

[0044] Then, the water outlet pipe 5 is moved from the inlet / outlet semi-circular header 301 to the conveying semi-circular header 302, and the original water outlet pipe 5 is sealed by welding with a blind flange 7.

[0045] After sealing, the inlet pipe 4 remains unchanged, while the outlet pipe 5 is changed. The outlet pipe 5 is changed from heat exchange pipes 1 and 2 to heat exchange pipes 5 and 6, thus achieving the sealing and isolation of the manifold.

[0046] Specifically, in use, the MGGH tube bundle heat exchanger includes a heat exchanger body 1, with multiple heat exchange tubes 101 fixedly installed inside the heat exchanger body 1. The port of each heat exchange tube 101 extends to the tube sheet outside the heat exchanger body 1 and is connected through a semi-circular header 3. The port module of the entire heat exchange tube 101 is provided with five semi-circular headers 3. The leftmost and rightmost inlet and outlet semi-circular headers 301 are connected to the outlet pipe 5 and the inlet pipe 4, respectively.

[0047] Each individual pipe is U-shaped. Pipes 1 and 4 form a U-shaped pipe, and similarly pipes 5 and 8 form a U-shaped pipe, pipes 9 and 12 form a group, pipes 13 and 16 form a group, pipes 2 and 3 form a group, pipes 6 and 7 form a group, pipes 10 and 11 form a group, and pipes 14 and 15 form a group.

[0048] Water enters through inlet pipe 4 from pipes 15 and 16. Since pipes 14 and 15 are a U-shaped pipe, and pipes 13 and 16 are another pipe, water entering pipe 15 will definitely exit from pipe 14. Similarly, water entering pipe 16 will definitely exit from pipe 13. Then, in the collection tanks that make up pipes 11, 12, 13, and 14, the water mixes. After that, pipes 11 and 12 become the inlet, flowing to pipes 9 and 10, and so on, with the water finally flowing out from pipes 1 and 2.

[0049] The semi-circular headers are for collecting water. Water enters through headers 15 and 16, and mixes in headers 11, 12, 13, and 14. In these headers, headers 11 and 12 act as outlets, allowing the water to continue flowing forward. The water then reaches headers 7, 8, 9, and 10, then headers 3, 4, 5, and 6, and finally flows out through the small headers 1 and 2.

[0050] When a leak occurs in a single heat exchange tube 101 and it is sealed and isolated: taking the U-shaped heat exchange tubes 101 of group 1 and 4 as an example, the U shape has only two openings, both of which are located at the top. Therefore, no matter where the leak occurs below the opening, both openings will be blocked, and water will not enter or leave.

[0051] When multiple heat exchange tubes 101 leak and need to be isolated by the header: Taking heat exchange tubes 1, 2, 3, and 4 as examples, firstly, all heat exchange tubes 101 101 101 101 101 101 101 101 20 30 40 3 ... Example

[0052] Please see Figure 3-4 Based on the above embodiments, in this method for handling external leakage of MGGH tube bundle heat exchangers, when the heat exchange tube 101 is sealed, the plug 2 is set as an airbag structure.

[0053] The airbag structure includes an inflatable baffle 6, an inflatable capsule 601, an air tube 602, a sealing tube 603, an air pump 604, and a through groove 605;

[0054] The semi-circular header 3 has a corresponding through groove 605 for accommodating the sealing tube 603. The radius of the through groove 605 is larger than the radius of the air pipe 602. After the uninflated inflation baffle 6 and inflation capsule 601 are placed into the semi-circular transport header 302 through the through groove 605, the inflation baffle 6 and inflation capsule 601 are partially inflated. The inflation capsule 601 in the partially inflated state is placed inside the port of the heat exchange tube 101. At the same time, the inflation baffle 6 covers the end face of the port of the heat exchange tube 101. Finally, the air pump 604 fully inflates the tube to block the end of the heat exchange tube 101.

[0055] One side of the inflation baffle 6 is fixedly connected to the inflation capsule 601. After the inflation capsule 601 is inflated through the air pipe 602, it presses against the inside of the heat exchange tube 101. The inflation capsule 601 is designed to resemble a threaded structure, blocking the inside of the heat exchange tube 101. At this time, the inflation baffle 6 is inflated and covers the end face of the heat exchange tube 101, thus working in conjunction with the double blocking function of the inflation capsule 601.

[0056] One end of the air tube 602 is fixedly connected to the inflation baffle 6, and the other end passes through the semi-circular header 3 and is connected to the air pump 604 through the inflation nozzle. The air pump 604 inflates the air tube 602, the inflation baffle 6, and the inflation capsule 601. A pressure gauge is installed on the tube of the air pump 604 to facilitate the control of the air pressure inside the inflation baffle 6 and the inflation capsule 601. Furthermore, the inflation nozzle at the other end of the air tube 602 can prevent the gas from automatically escaping after inflation, similar to the principle of a tire inflator.

[0057] The sealing tube 603 is sleeved on the outer wall of the air tube 602 and welded to the inside of the through groove 605. The sealing tube 603 starts from the top of the air tube 602, sleeved on the outer wall of the air tube 602 and simultaneously in contact with the inner wall of the through groove 605.

[0058] The sealing tube 603 and the air tube 602 maintain relative sliding, and sealing rings are set at both ends inside to keep them sealed. By sliding the air tube 602 up and down, the inflation baffle 6 and the inflation capsule 601 can be pressed down periodically to prevent them from falling out of the heat exchange tube 101.

[0059] Specifically, in use, when the plug 2 is set as an airbag structure to block both ends of the heat exchange tube, according to the position of the heat exchange tube in the drawing, firstly, a through groove 605 is opened inside the semi-circular header 3. After the uninflated inflation baffle 6 and inflation capsule 601 are placed into the conveying semi-circular header 302 through the through groove 605, the inflation nozzle of the air pipe 602 is connected to the air pump 604 to partially inflate the inflation baffle 6 and inflation capsule 601. The air pipe 602 is moved to place the inflation capsule 601 in the partially inflated state inside the port of the heat exchange tube 101. At the same time, the inflation baffle 6 covers the end face of the port of the heat exchange tube 101. Finally, the air pump 604 is used to fully inflate the tube to block the end of the heat exchange tube 101.

[0060] After the air pump 604 is fully inflated, remove the air pump 604, and start from the top of the air tube 602, fit the sealing tube 603 onto the outer wall of the air tube 602 and at the same time adhere to the inner wall of the through groove 605. At the same time, the sealing tube 603 and the air tube 602 maintain relative sliding, and sealing rings are set at both ends inside to keep them sealed. Then, weld the sealing tube 603 into the inside of the through groove 605 to maintain the seal.

[0061] The solution in this embodiment can be selectively combined with solutions in other embodiments.

[0062] It should be noted that although the above embodiments have been described herein, this does not limit the scope of patent protection of this invention. Therefore, any changes and modifications made to the embodiments described herein based on the innovative concept of this invention, or equivalent structural, procedural, or functional transformations made using the description and drawings of this invention, directly or indirectly applying the above technical solutions to other related technical fields, are all included within the scope of protection of this invention.

Claims

1. A method for treating external leakage in MGGH tube bundle heat exchangers, characterized in that, The specific steps are as follows: S1. Each module of the MGGH tube bundle heat exchanger is equipped with five semi-circular headers (3), wherein: The inlet and outlet ends are equipped with semi-circular headers (301), which are internally connected to two heat exchange tubes (101). The intermediate conveying end is equipped with a semi-circular conveying header (302), which is internally connected to four heat exchange tubes (101). S2. Water is injected into the semi-circular header (301) at one end through the water inlet pipe (4), and then flows through the heat exchange pipe (101) into the conveying semi-circular header (302) for mixing. Finally, it flows into the semi-circular header (301) at the other end and is discharged through the water outlet pipe (5), thereby achieving heat exchange. S3. When a single heat exchange tube (101) leaks, the single heat exchange tube (101) is used for sealing and isolation: the damaged, U-shaped heat exchange tube (101) is found according to the online water injection leak detection, and the other end of the tube is found according to the layout diagram. Then, the two ends of the heat exchange tube (101) are sealed with plugs (2) and fully sealed with electric welding. S4. When multiple heat exchange tubes (101) are leaking, multiple heat exchange tube headers are used for isolation: First, all the leaking heat exchange tubes (101) are sealed using the method in step S3. Then move the water outlet pipe (5) from the inlet and outlet semi-circular header (301) to the conveying semi-circular header (302), and at the same time seal the original water outlet pipe (5) by welding and sealing with a blind flange (7); After sealing, the inlet pipe (4) remains unchanged, while the outlet pipe (5) is changed to achieve the sealing and isolation of the manifold.

2. The method for handling external leakage in an MGGH tube bundle heat exchanger according to claim 1, characterized in that: The radius of the conveying semi-circular header (302) is greater than the radius of the inlet / outlet semi-circular header (301).

3. The method for handling external leakage in an MGGH tube bundle heat exchanger according to claim 1, characterized in that: The plug (2) mentioned in step S3 is set as a solid structure or an airbag structure with concentric shafts and large and small heads.

4. The method for handling external leakage in an MGGH tube bundle heat exchanger according to claim 3, characterized in that: The airbag structure includes an inflatable baffle (6), an inflatable capsule (601), an air tube (602), a sealing tube (603), an air pump (604), and a through groove (605). The inflation baffle (6) is fixedly connected to the inflation capsule (601) on one side. After the inflation capsule (601) is inflated through the air pipe (602), it is placed inside the port of the heat exchange tube (101). At this time, the inflation baffle (6) is inflated and covers the end face of the port of the heat exchange tube (101).

5. A method for handling external leakage in an MGGH tube bundle heat exchanger according to claim 4, characterized in that: One end of the air tube (602) is fixedly connected to the inflation baffle (6), and the other end passes through the semi-circular header (3) and is connected to the air pump (604) through the inflation nozzle. The air pump (604) inflates the air tube (602), the inflation baffle (6), and the inflation capsule (601).

6. A method for treating external leakage in an MGGH tube bundle heat exchanger according to claim 5, characterized in that: The semi-circular header (3) has a corresponding through groove (605) for accommodating the sealing tube (603). After the uninflated inflation baffle (6) and inflation capsule (601) are placed into the semi-circular transport header (302) through the through groove (605), the inflation baffle (6) and inflation capsule (601) are partially inflated. The inflation capsule (601) in the partially inflated state is placed inside the port of the heat exchange tube (101). At the same time, the inflation baffle (6) covers the end face of the port of the heat exchange tube (101). Finally, the air pump (604) is used to fully inflate the tube and block the end of the heat exchange tube (101).

7. A method for treating external leakage in an MGGH tube bundle heat exchanger according to claim 6, characterized in that: The sealing tube (603) is sleeved on the outer wall of the air tube (602), and the sealing tube (603) is welded to the inside of the through groove (605); The sealing tube (603) and the air tube (602) slide relative to each other, and sealing rings are provided at both ends inside to keep them sealed.

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