CN211824931U

CN211824931U - Heat exchanger leak detection tool

Info

Publication number: CN211824931U
Application number: CN202020526802.7U
Authority: CN
Inventors: 陈伟忠; 冯嘉; 赵学朋
Original assignee: Jiangsu Shengwei Gas Technology Co ltd
Current assignee: Jiangsu Shengwei Gas Technology Co ltd
Priority date: 2020-04-10
Filing date: 2020-04-10
Publication date: 2020-10-30
Anticipated expiration: 2030-04-10

Abstract

The utility model discloses a heat exchanger leak hunting frock, including first backup pad, first inflation axle sleeve and first connecting axle, first backup pad is equipped with first shaft hole, the both sides in first shaft hole are equipped with first screw hole respectively, first roof pressure bolt is equipped with soon in the first screw hole, the downside at first backup pad is fixed to first inflation axle sleeve, be equipped with a plurality of first inflation openings on the lower half perisporium of first inflation axle sleeve, first connecting axle includes the first cylinder portion by lower supreme setting, first cylinder portion and first screw post, be equipped with first seal groove and first sealing washer on the perisporium of first cylinder portion, first screw post is equipped with first lock nut by lower supreme first inflation axle sleeve and first backup pad and in the upside position of first backup pad soon, first connecting axle is equipped with the air flue along the axis. The device has the advantages of simple structure, low cost, simple and convenient operation, safety, reliability and accurate detection.

Description

Heat exchanger leak detection tool

Technical Field

The utility model relates to a leak hunting device, concretely relates to leak hunting frock for heat exchanger heat exchange tube.

Background

The U-shaped tube heat exchanger is composed of a shell and a tube bundle, wherein the tube bundle is formed by combining a plurality of U-shaped tubes, and the end parts of the tube bundle are connected together through a sealing plate. When the U-shaped pipe heat exchanger leaks, only the leaked U-shaped pipe needs to be replaced by a new U-shaped pipe. For the leakage detection of the U-shaped pipe, because the pipe pass pressure is far higher than that of the shell pass, the leakage points are difficult to find through the existing PT (potential Transformer) penetration detection and shell pass ammonia leakage detection, if a pipe pass airtight test (a pipe bundle is placed into water) is adopted, only a small amount of small bubbles can appear, and because the U-shaped pipe is tightly arranged, the finding of the U-shaped pipe with specific leakage is troublesome.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a heat exchanger leak hunting frock, it has simple structure, low cost, easy and simple to handle, safe and reliable, detects accurate advantage.

In order to solve the problems in the prior art, the utility model provides a heat exchanger leak detection tool, which comprises a first supporting plate, a first expansion shaft sleeve and a first connecting shaft, wherein the middle part of the first supporting plate is provided with a first shaft hole; the first expansion shaft sleeve is fixed on the lower side of the first supporting plate and is coaxial with the first shaft hole, and a plurality of first expansion gaps are formed in the peripheral wall of the lower half part of the first expansion shaft sleeve; first connecting axle includes by first cylinder portion, first round platform portion and the first screw thread post of supreme setting down, is equipped with first seal groove on the perisporium of first cylinder portion, installs first sealing washer in the first seal groove, and first screw thread post is by supreme first inflation axle sleeve and the first backup pad of passing down, and first lock nut is equipped with soon in the upside position of first backup pad to first screw thread post, and first connecting axle is equipped with the air flue along the axis.

Further, the utility model relates to a heat exchanger leak hunting frock still includes the adapter, the upper half of adapter is cylindrical and is equipped with the screw thread, and the lower half of adapter is hexagonal prism shape, and the adapter is equipped with coaxial first mounting hole and air vent from bottom to top, and the diameter of first mounting hole is greater than the diameter of air vent; the adapter is equipped with the sealing ring through the internal thread spiral dress in the upper end of first screw thread post on the first mounting hole week wall between the upper end of first screw thread post and the adapter.

Further, the utility model relates to a heat exchanger leak hunting frock, wherein, the internal perisporium lower extreme of first inflation axle sleeve just makes its first boss portion with first connecting axle match the setting for the conical surface.

Further, the utility model relates to a heat exchanger leak hunting frock, wherein, first inflation axle sleeve is including the first connecting portion and the first inflation portion that distribute from top to bottom, and the external diameter of first connecting portion is greater than the external diameter of first inflation portion, and first connecting portion pass through welded fastening on first backup pad.

Furthermore, the utility model relates to a heat exchanger leak hunting tool, wherein, the first expansion gap is provided with four and is evenly distributed along the circumference of the first expansion shaft sleeve; the first sealing groove is provided with more than two sealing grooves at intervals along the axial direction of the first connecting shaft.

Furthermore, the utility model relates to a heat exchanger leak hunting frock still includes second backup pad, second expansion shaft sleeve and second connecting axle, the middle part of second backup pad is equipped with the second shaft hole, and the second backup pad is equipped with the second screw hole respectively in the both sides position of second shaft hole, and the second screw hole is equipped with the second roof pressure bolt soon; the second expansion shaft sleeve is fixed on the lower side of the second support plate and is coaxial with the second shaft hole, and a plurality of second expansion gaps are formed in the peripheral wall of the lower half part of the second expansion shaft sleeve; the second connecting shaft comprises a second cylindrical part, a second circular truncated cone part and a second threaded column which are arranged from bottom to top, a second sealing groove is formed in the peripheral wall of the second cylindrical part, a second sealing ring is installed in the second sealing groove, and the second threaded column penetrates through a second expansion shaft sleeve and a second supporting plate from bottom to top and is provided with a second locking nut in a screwed mode at the position of the upper side of the second supporting plate.

Further, the utility model relates to a heat exchanger leak hunting frock still includes the operating head, the operating head is hexagonal prism shape, and the lower half of operating head is equipped with the second mounting hole, and the operating head is adorned soon in the upper end of second screw thread post through the internal thread on the second mounting hole perisporium.

Further, the utility model relates to a heat exchanger leak hunting frock, wherein, the interior perisporium lower extreme of second inflation axle sleeve just makes its second boss portion with the second connecting axle match the setting for the conical surface.

Further, the utility model relates to a heat exchanger leak hunting frock, wherein, second inflation axle sleeve is including the second connecting portion and the second inflation portion that distribute from top to bottom, and the external diameter of second connecting portion is greater than the external diameter of second inflation portion, and the second connecting portion pass through welded fastening in the second backup pad.

Furthermore, the utility model relates to a heat exchanger leak hunting tool, wherein, the second expansion gap is provided with four and is evenly distributed along the circumference of the second expansion shaft sleeve; the second sealing grooves are more than two in axial interval along the second connecting shaft.

The utility model relates to a heat exchanger leak hunting frock compares with prior art, has following advantage: the utility model is provided with the first support plate, the first expansion shaft sleeve and the first connecting shaft, so that the first support plate is provided with the first shaft hole in the middle part thereof, the first support plate is respectively provided with the first threaded holes at the two sides of the first shaft hole, and the first jacking bolt is screwed in the first threaded hole; fixing a first expansion shaft sleeve on the lower side of a first supporting plate and enabling the first expansion shaft sleeve to be coaxial with a first shaft hole, and arranging a plurality of first expansion gaps on the peripheral wall of the lower half part of the first expansion shaft sleeve; the first connecting shaft is provided with a first cylindrical part, a first circular table part and a first threaded column which are distributed from bottom to top, a first sealing groove is formed in the peripheral wall of the first cylindrical part, a first sealing ring is arranged in the first sealing groove, the first threaded column penetrates through a first expansion shaft sleeve and a first supporting plate from bottom to top, a first locking nut is screwed in the upper side position of the first supporting plate, and the first connecting shaft is provided with an air passage along the axis. Therefore, the heat exchanger leak detection tool is simple in structure, low in cost, simple and convenient to operate, safe, reliable and accurate in detection. In practical application, when the U-shaped pipe heat exchanger leaks, one end of a certain U-shaped pipe is plugged at first; then inserting the first cylindrical part and the first expansion shaft sleeve of the first connecting shaft into the other end of the U-shaped pipe, and expanding the first expansion shaft sleeve from the first round table part of the first connecting shaft by rotating the first locking nut; then the upper end of the first threaded column of the first connecting shaft is connected with a high-pressure air source through a pipeline, and a control valve and a pressure gauge are arranged in the pipeline; and then introducing high-pressure gas into the U-shaped pipe, maintaining the pressure for about 30 minutes, and determining whether the U-shaped pipe leaks or not by judging whether the air pressure (the reading of a pressure gauge) changes or not. After the leakage detection of the U-shaped pipe is finished, firstly, reversely rotating a first locking nut to enable the first locking nut to have a certain distance with a first supporting plate; then the first jacking bolt is rotated to jack the sealing plate at the end part of the tube bundle, and the first expansion shaft sleeve is gradually restored and moved out of the U-shaped tube under the jacking action of the first jacking bolt; the first cylindrical portion of the first connecting shaft is then pulled out of the U-shaped tube. And (4) completing leakage detection of the other U-shaped pipes in the pipe bundle according to the method. The first sealing groove and the first sealing ring are arranged on the peripheral wall of the first cylindrical part, so that the sealing reliability of connection is ensured; by arranging the first expansion shaft sleeve and the first circular table part matched with the first expansion shaft sleeve, the first expansion shaft sleeve and the first connecting shaft can be prevented from being ejected out of the U-shaped pipe by high-pressure gas, and the reliability and the safety of connection are ensured; by arranging the first supporting plate and the first jacking bolt, the first expansion shaft sleeve can be gradually restored and moved out of the U-shaped pipe during disassembly, so that the simplicity and the stability of the disassembly operation are improved; and the tube bundle does not need to be moved in the whole leakage detection process, so that the safety is improved.

The leak detection tool of the heat exchanger according to the present invention will be described in further detail with reference to the following embodiments shown in the drawings.

Drawings

Fig. 1 is a schematic structural diagram of a first embodiment of a leak detection tool for a heat exchanger of the present invention;

fig. 2 is a top view of a first support plate in a first embodiment of the leak detection tool for a heat exchanger of the present invention;

FIG. 3 is a view taken along line A-A of FIG. 2;

fig. 4 is a front view of a first expansion bush in a first embodiment of the leak detection tool for a heat exchanger of the present invention;

FIG. 5 is a view taken along line B-B of FIG. 4;

fig. 6 is a front view of a first connecting shaft in a first embodiment of the leak detection tool for a heat exchanger of the present invention;

FIG. 7 is a view taken along line C-C of FIG. 6;

fig. 8 is a front view of a transfer joint in a first embodiment of a leak detection tool for a heat exchanger according to the present invention;

FIG. 9 is a view from direction D-D of FIG. 8;

fig. 10 is a schematic structural diagram of a second embodiment of the leak detection tool for a heat exchanger of the present invention.

Detailed Description

It should be noted that, in the present invention, the terms of upper, lower, left, right, front, rear, etc. are only described according to the accompanying drawings, so as to facilitate understanding, and are not intended to limit the technical solution and the scope of the present invention.

As shown in fig. 1 to 9, the utility model relates to a first embodiment of a leak detection tool for a heat exchanger, which comprises a first supporting plate 1, a first expansion shaft sleeve 2 and a first connecting shaft 3. A first shaft hole 11 is formed in the middle of a first support plate 1, first threaded holes 12 are respectively formed in the two sides of the first shaft hole 11 of the first support plate 1, and a first jacking bolt 13 is screwed in the first threaded holes 12. The first expansion bush 2 is fixed to the lower side of the first support plate 1 so as to be coaxial with the first axial hole 11, and a plurality of first expansion slits 21 are provided in the lower half peripheral wall of the first expansion bush 2. The first connecting shaft 3 is provided with a first cylindrical part 31, a first circular table part 32 and a first threaded column 33 which are connected into a whole and distributed from bottom to top, a first sealing groove 34 is arranged on the peripheral wall of the first cylindrical part 31, a first sealing ring (not shown in the figure) is arranged in the first sealing groove 34, the first threaded column 33 penetrates through the first expansion shaft sleeve 2 and the first supporting plate 1 from bottom to top, a first locking nut 4 is screwed at the upper side position of the first supporting plate 1, and the first connecting shaft 3 is further provided with an air passage 35 along the axis.

The heat exchanger leak detection tool is simple in structure, low in cost, simple and convenient to operate, safe, reliable and accurate in detection. In practical application, when the U-tube heat exchanger leaks, one end of one U-tube 7 is first plugged. Then, the first cylindrical portion 31 of the first connecting shaft 3 and the first expansion boss 2 are inserted into the other end of the U-shaped pipe 7, and the first boss portion 32 of the first connecting shaft 3 is expanded by rotating the first lock nut 4 to expand the first expansion boss 2. Then, the upper end of the first threaded column 33 of the first connecting shaft 3 is connected with a high-pressure air source through a pipeline, and a control valve and a pressure gauge are arranged in the pipeline. Then, high-pressure gas is introduced into the U-shaped pipe 7 and the pressure is maintained for about 30 minutes, and whether the U-shaped pipe 7 leaks can be determined by whether the pressure (the reading of a pressure gauge) changes. After the leakage detection of the U-shaped pipe 7 is completed, the first locking nut 4 is first rotated in the reverse direction to have a certain distance from the first supporting plate 1. Then the first jacking bolt 13 is rotated to jack the closing plate at the end of the tube bundle, and the first expansion shaft sleeve 2 is gradually restored and removed from the U-shaped tube 7 under the jacking action of the first jacking bolt 13. Subsequently, the first cylindrical portion 31 of the first connecting shaft 3 is pulled out from the U-shaped pipe 7. And (4) completing leakage detection of the other U-shaped pipes in the pipe bundle according to the method. The utility model ensures the sealing reliability of the connection by arranging the first sealing groove 34 and the first sealing ring on the peripheral wall of the first cylindrical part 31; by arranging the first expansion shaft sleeve 2 and the first circular table part 32 matched with the first expansion shaft sleeve, the first expansion shaft sleeve 2 and the first connecting shaft 3 can be prevented from being ejected out of the U-shaped pipe by high-pressure gas, and the reliability and the safety of connection are ensured; by arranging the first supporting plate 1 and the first jacking bolt 13, the first expansion shaft sleeve 2 can be gradually restored and moved out of the U-shaped pipe during disassembly, so that the simplicity and the stability of disassembly operation are improved; and the tube bundle does not need to be moved in the whole leakage detection process, so that the safety is improved. It should be noted that, in practical applications, the present invention generally designs the diameter of the first cylindrical portion 31 to be larger than the inner diameter of the first expansion bush 2 and slightly smaller than the outer diameter of the first expansion bush 2, so as to ensure the sealing performance of the first sealing ring and the expansion reliability of the first expansion bush 2.

As an optimization scheme, this embodiment has still set up adapter 5, make the first half of adapter 5 adopt cylindrically and set up the screw thread, in order to improve the convenience with the tube coupling, make the lower half of adapter 5 adopt hexagonal prism shape, so that with first lock nut 4 cooperation operation first connecting axle 3, and make adapter 5 by lower supreme coaxial first mounting hole 51 and the air vent 52 of setting up, and make the diameter of first mounting hole 51 be greater than the diameter of air vent 52, so that installation adapter 5 and intercommunication air flue. The adapter 5 is screwed on the upper end of the first threaded column 33 through the internal thread on the peripheral wall of the first mounting hole 51, and a seal ring 6 is arranged between the upper end of the first threaded column 33 and the adapter 5 to ensure the sealing performance. The adapter 5 of the structure has the advantages of simple structure and convenience in disassembly and assembly, and the convenience in operation is improved.

As an optimized scheme, in the present embodiment, the lower end of the inner peripheral wall of the first expansion shaft sleeve 2 is made to be a conical surface and is arranged to match with the first circular table portion 32 of the first connecting shaft 3, so that the stability of the expansion action is improved. Meanwhile, the first expansion shaft sleeve 2 is provided with a first connecting part 22 and a first expansion part 23 which are connected into a whole and distributed up and down, and the outer diameter of the first connecting part 22 is larger than that of the first expansion part 23, wherein the first connecting part 22 is fixed on the first supporting plate 1 through welding. This setting has formed spacing platform in the junction of first connecting portion 22 and first inflation portion 23, can play the effect of blockking to the tip of U type pipe, has improved the unity and the standardized degree of seepage detection. It should be noted that the first connection portion 22 and the first support plate 1 are not limited to be fixed by welding, and may be fixed by bolting. In order to enhance the structural stability, the present embodiment provides four first expansion slits 21 and makes them uniformly distributed in the circumferential direction of the first expansion sleeve 2. In order to enhance the reliability of the sealing property, the present embodiment provides two or more first seal grooves 34 spaced apart from each other in the axial direction of the first connecting shaft 3.

As shown in fig. 10, the second embodiment of the leak detection tool for a heat exchanger of the present invention includes a second supporting plate 1 ', a second expansion shaft sleeve 2 ' and a second connecting shaft 3 '. And arranging a second shaft hole in the middle of the second support plate 1 ', respectively arranging second threaded holes in the second support plate 1' at the two sides of the second shaft hole, and screwing a second jacking bolt in the second threaded holes. The second expansion bush 2 ' is fixed to the lower side of the second support plate 1 ' so as to be coaxial with the second axial hole, and a plurality of second expansion slits are provided in the lower half peripheral wall of the second expansion bush 2 '. The second connecting shaft 3 ' is provided with a second cylindrical part, a second circular truncated cone part and a second threaded column which are integrally connected and distributed from bottom to top, a second sealing groove is formed in the peripheral wall of the second cylindrical part, a second sealing ring is arranged in the second sealing groove, the second threaded column penetrates through the second expansion shaft sleeve 2 ' and the second supporting plate 1 ' from bottom to top, and a second locking nut 4 ' is screwed at the upper side position of the second supporting plate 1 '. In practical application, the second cylindrical portion of the second connecting shaft 3 ' and the second expansion shaft sleeve 2 ' are inserted into one end of the U-shaped pipe, the second locking nut 4 ' is rotated to expand the second expansion shaft sleeve 2 ' from the second circular table portion of the second connecting shaft 3 ', the end of the U-shaped pipe can be plugged through the second sealing ring, and the second expansion shaft sleeve 2 ' and the second connecting shaft 3 ' can be prevented from being ejected out by high-pressure gas. After the U-shaped pipe leakage is detected, the second locking nut 4 ' is rotated reversely to enable a certain distance to be reserved between the second locking nut and the second supporting plate 1 ', the second jacking bolt is rotated to enable the second locking nut to jack the sealing plate at the end part of the pipe bundle, the second expansion shaft sleeve 2 ' can be gradually restored and moved out of the U-shaped pipe, and then the second cylindrical part of the second connecting shaft is pulled out of the U-shaped pipe. It should be noted that, in practical application, the utility model discloses let second backup pad 1 ' and first backup pad 1 adopt the same structure, let second inflation axle sleeve 2 ' and first inflation axle sleeve 2 adopt the same structure to simplify design and technology, improve the standardization level, and second connecting axle 3 ' only need not set up the air flue compared with first connecting axle 3; the combination of the first support plate 1, the first expansion shaft sleeve 2 and the first connecting shaft 3 is used as a gas transmission device so as to input high-pressure gas into the U-shaped pipe, and the combination of the second support plate 1 ', the second expansion shaft sleeve 2 ' and the second connecting shaft 3 ' is used as a plugging device so as to plug one end of the U-shaped pipe, and the connection, separation and operation modes of the two and the U-shaped pipe are completely the same.

As an optimized scheme, the present embodiment further provides an operating head 5 ', and the operating head 5' is made into a hexagonal prism shape, the lower half portion of the operating head 5 'is provided with a second mounting hole, and the operating head 5' is screwed on the upper end of the second threaded column through the internal thread on the peripheral wall of the second mounting hole, so as to cooperate with the second lock nut 4 'to operate the second connecting shaft 3'. In order to improve the stability of the expansion action, the lower end of the inner peripheral wall of the second expansion shaft sleeve 2 'is also provided with a conical surface, and the conical surface is matched with the second circular table part of the second connecting shaft 3'. In order to improve the uniformity and standardization of the operation, the embodiment also provides the second expansion shaft sleeve 2 'with a second connecting part and a second expansion part which are distributed up and down, and fixes the second connecting part on the second support plate 1' by welding, wherein the outer diameter of the second connecting part is larger than that of the second expansion part, so that the connecting part of the second connecting part and the second expansion part forms a limit table to block the end part of the U-shaped pipe. In order to enhance the structural stability, the present embodiment also provides four second expansion slits uniformly along the circumferential direction of the second expansion sleeve 2'. In order to enhance the reliability of the sealing property, in this embodiment, two or more second sealing grooves are also provided at intervals along the axial direction of the second connecting shaft 3'.

The above embodiments are only descriptions of the preferred embodiments of the present invention, and are not intended to limit the scope of the claimed invention, and various modifications made by those skilled in the art according to the technical solutions of the present invention should fall within the scope of the present invention as defined by the claims.

Claims

1. The leak detection tool for the heat exchanger is characterized by comprising a first supporting plate (1), a first expansion shaft sleeve (2) and a first connecting shaft (3), wherein a first shaft hole (11) is formed in the middle of the first supporting plate (1), first threaded holes (12) are formed in the first supporting plate (1) on two sides of the first shaft hole (11), and a first jacking bolt (13) is screwed in each first threaded hole (12); the first expansion shaft sleeve (2) is fixed on the lower side of the first supporting plate (1) and is coaxial with the first shaft hole (11), and a plurality of first expansion gaps (21) are arranged on the peripheral wall of the lower half part of the first expansion shaft sleeve (2); first connecting axle (3) are equipped with first seal groove (34) including first cylinder portion (31), first round platform portion (32) and first screw post (33) by supreme down setting on the perisporium of first cylinder portion (31), install first sealing washer in first seal groove (34), first screw post (33) are by supreme first inflation axle sleeve (2) and first backup pad (1) of passing down, first screw post (33) are equipped with first lock nut (4) soon in the upside position of first backup pad (1), first connecting axle (3) are equipped with air flue (35) along the axis.

2. The leak detection tool for the heat exchanger is characterized by further comprising an adapter (5), wherein the upper half part of the adapter (5) is cylindrical and provided with threads, the lower half part of the adapter (5) is hexagonal, the adapter (5) is provided with a first mounting hole (51) and a vent hole (52) which are coaxial from bottom to top, and the diameter of the first mounting hole (51) is larger than that of the vent hole (52); the adapter (5) is rotatably installed at the upper end of the first threaded column (33) through internal threads on the peripheral wall of the first installation hole (51), and a sealing ring (6) is arranged between the upper end of the first threaded column (33) and the adapter (5).

3. The leak detection tool for the heat exchanger is characterized in that the lower end of the inner peripheral wall of the first expansion shaft sleeve (2) is a conical surface, and the lower end of the inner peripheral wall of the first expansion shaft sleeve is matched with the first circular table part (32) of the first connecting shaft (3).

4. The leak detection tool for the heat exchanger is characterized in that the first expansion shaft sleeve (2) comprises a first connecting part (22) and a first expansion part (23) which are distributed up and down, the outer diameter of the first connecting part (22) is larger than that of the first expansion part (23), and the first connecting part (22) is fixed on the first supporting plate (1) through welding.

5. The leak detection tool for the heat exchanger is characterized in that the number of the first expansion gaps (21) is four, and the first expansion gaps are uniformly distributed along the circumferential direction of the first expansion shaft sleeve (2); the first sealing grooves (34) are arranged at intervals along the axial direction of the first connecting shaft (3).

6. The leak detection tool for the heat exchanger is characterized by further comprising a second supporting plate (1 '), a second expansion shaft sleeve (2 ') and a second connecting shaft (3 '), wherein a second shaft hole is formed in the middle of the second supporting plate (1 '), second threaded holes are formed in the positions, on two sides of the second shaft hole, of the second supporting plate (1 '), and a second jacking bolt is screwed in the second threaded holes; the second expansion shaft sleeve (2 ') is fixed on the lower side of the second support plate (1 ') and is coaxial with the second shaft hole, and a plurality of second expansion gaps are formed in the peripheral wall of the lower half part of the second expansion shaft sleeve (2 '); the second connecting shaft (3 ') comprises a second cylindrical part, a second circular truncated cone part and a second threaded column which are arranged from bottom to top, a second sealing groove is formed in the peripheral wall of the second cylindrical part, a second sealing ring is installed in the second sealing groove, the second threaded column penetrates through the second expansion shaft sleeve (2 ') and the second supporting plate (1 ') from bottom to top, and a second locking nut (4 ') is screwed at the upper side position of the second supporting plate (1 ').

7. The leak detection tool for the heat exchanger is characterized by further comprising an operating head (5 '), wherein the operating head (5') is in a hexagonal prism shape, a second mounting hole is formed in the lower half portion of the operating head (5 '), and the operating head (5') is screwed at the upper end of the second threaded column through internal threads on the peripheral wall of the second mounting hole.

8. The leak detection tool for the heat exchanger as claimed in claim 7, wherein the lower end of the inner peripheral wall of the second expansion shaft sleeve (2 ') is a conical surface and is matched with the second circular table part of the second connecting shaft (3').

9. The leak detection tool for the heat exchanger is characterized in that the second expansion shaft sleeve (2 ') comprises a second connecting part and a second expansion part which are distributed up and down, the outer diameter of the second connecting part is larger than that of the second expansion part, and the second connecting part is fixed on the second support plate (1') through welding.

10. The leak detection tool for the heat exchanger according to claim 9, wherein the number of the second expansion gaps is four, and the second expansion gaps are uniformly distributed along the circumferential direction of the second expansion shaft sleeve (2'); the second sealing grooves are arranged at intervals along the axial direction of the second connecting shaft (3').