CN220120321U

CN220120321U - Pressure pipeline air tightness detection device for constructional engineering

Info

Publication number: CN220120321U
Application number: CN202320699969.7U
Authority: CN
Inventors: 郭超
Original assignee: Shanghai Yuyi Construction And Installation Engineering Co ltd
Current assignee: Shanghai Yuyi Construction And Installation Engineering Co ltd
Priority date: 2023-04-03
Filing date: 2023-04-03
Publication date: 2023-12-01
Anticipated expiration: 2033-04-03

Abstract

The utility model provides a pressure pipeline air tightness detection device for constructional engineering, which comprises a box body, a lifting assembly and a detection assembly, wherein the lifting assembly is arranged on the box body, the detection assembly is in transmission connection with the lifting assembly, the lifting assembly drives the detection assembly to lift upwards along the height direction of the box body, the detection assembly comprises a sliding piece, an inflating piece and a positioning piece, the sliding piece is in transmission connection with the lifting assembly, the inflating piece is arranged on the sliding piece, the positioning piece is fixedly arranged on the sliding piece, and the positioning piece is in transmission connection with the inflating piece, the inflating piece comprises an inflating end and an abutting sealing end, the inflating end and the abutting sealing end are respectively arranged at two ends of the sliding piece, the positioning piece is respectively in transmission connection with the inflating end and the abutting sealing end, and is used for driving the inflating end and the abutting sealing end to perform synchronous reverse movement, so that two ends of a pipeline to be detected are respectively in abutting sealing with the inflating end and the abutting sealing end, detection errors are reduced, and the accuracy of detection data is improved.

Description

Pressure pipeline air tightness detection device for constructional engineering

Technical Field

The utility model relates to the technical field of air tightness detection devices, in particular to a pressure pipeline air tightness detection device for construction engineering.

Background

The pressure pipeline refers to all pipelines bearing internal pressure or external pressure, no matter how the medium in the pipeline is, the pressure pipeline is a part of the pipelines, after the production of the pressure pipeline pipe is finished, the pipeline is required to be subjected to air tightness detection, an air tightness detection device is used for detecting whether the air tightness of the pipeline is good, and the pipeline with poor air tightness can be screened out to obtain the pipeline with good air tightness required by people.

In the prior art, the pressure in the pipeline is monitored in real time by the pressure gauge by inflating the pressure pipeline pipe generally, and the pipeline is required to be connected with the detection device in the pressure detection process, so that when the tightness between the pipeline and the detection device is insufficient, the pressure gauge can reduce the pressure value, and the pressure gauge is easy to cause the detection personnel to judge that the air tightness of the pipe has certain influence, thereby causing certain loss.

Therefore, there is a need for improvement, and the utility model provides a pressure pipeline air tightness detection device for construction engineering.

Disclosure of Invention

Aiming at the defects existing in the prior art, the utility model aims to provide a pressure pipeline air tightness detection device for construction engineering, which comprises the following specific scheme: the utility model provides a pressure pipe gas tightness detection device for building engineering, includes box, lifting unit, detection subassembly, lifting unit set up in on the box, just detection subassembly with the transmission is connected between the lifting unit, lifting unit drive detection subassembly is along the direction of height of box goes up and down,

the detection assembly comprises a sliding part, an inflating part and a positioning part, wherein the sliding part is in transmission connection with the lifting assembly, the inflating part is arranged on the sliding part, the positioning part is fixedly arranged on the sliding part, the positioning part is in transmission connection with the inflating part, the inflating part comprises an inflating end and an abutting sealing end, the inflating end and the abutting sealing end are respectively arranged at two ends of the sliding part, the positioning part is respectively in transmission connection with the inflating end and the abutting sealing end, and the positioning part is used for driving the inflating end to perform synchronous reverse movement between the abutting sealing ends, so that two ends of a pipeline to be detected are respectively in abutting sealing with the inflating end and the abutting sealing end.

Further, the sliding piece comprises a sliding plate, a first sliding block and a second sliding block, wherein the first sliding block and the second sliding block are respectively arranged at two ends of the sliding plate, and the first sliding block and the second sliding block are respectively matched with the sliding plate in a sliding manner.

Further, the inflation end comprises an inflator pump, a pressure gauge and a first mounting table, wherein the first mounting table is fixedly arranged at the top of the first sliding block, the inflator pump is fixedly arranged on the first mounting table, the pressure gauge and the inflator pump are communicated, the inflator pump is used for detecting real-time pressure in a pipeline to be detected, and a first sealing part is formed on one side, close to the second sliding block, of the inflator pump and used for abutting against and sealing a port of the pipeline to be detected.

Further, the conflict sealing end includes second mount table, second sealing portion, supporting part, the second mount table fixed set up in the top of second sliding block, the second sealing portion fixed set up in the top of second mount table, just the second sealing portion with set up relatively between the first sealing portion, the supporting part fixed set up in the second sealing portion is close to one side of inflation end for support the pipeline that awaits measuring, make the pipeline that awaits measuring can be on a parallel with the center connecting line between first sealing portion and the second sealing portion and place.

Further, the setting element includes first driving motor, two-way threaded rod, first driving motor fixed set up in one side of sliding plate, just two-way threaded rod with the transmission is connected between first driving motor's the pivot, screw thread fit between two ends of two-way threaded rod respectively with first sliding block, the second sliding block, first driving motor drive first sliding block the second sliding block between carry out synchronous opposite movement, to be located first sliding block the pipeline that awaits measuring between the second sliding block presss from both sides tightly.

Further, the sliding plate is located first sliding block be provided with first supporting component between the second sliding block, first supporting component includes mounting panel, cylinder, supporting shoe, deflector, the mounting panel set up in the top of sliding plate, two the deflector sets up respectively in the both sides of mounting panel, the supporting shoe sets up in two between the deflector, just the deflector with sliding fit between the supporting shoe, the one end of cylinder with fixed connection between the mounting panel, the other end with the bottom fixed connection of supporting shoe, the top of supporting shoe is formed with the centre gripping groove that is used for supporting the pipeline that awaits measuring.

Further, a second supporting component is arranged on one side, close to the second sliding block, of the first sliding block, and the second supporting component is consistent with the first supporting component in structure and function.

Further, the lifting assembly comprises a lifting motor, a first positioning plate, a threaded rod, a second positioning plate and a guide rod, wherein the first positioning plate is fixedly arranged at the top of the box body, the first positioning plate and the second positioning plate are respectively arranged at two sides of the box body, the lifting motor is fixedly arranged on the first positioning plate, the threaded rod is connected with a rotating shaft of the lifting motor in a transmission manner, the threaded rod sequentially penetrates through the first positioning plate, the sliding plate is connected with the bottom of the box body in a rotating manner, the threaded rod is in threaded fit with the sliding plate, and the guide rod penetrates through the sliding plate and is fixedly connected with the bottom of the box body and the second positioning plate.

Compared with the prior art, the utility model has the following beneficial effects:

(1) According to the utility model, the lifting assembly and the detection assembly are arranged on the box body, so that the pipeline to be detected is fixed on the detection assembly, the pipeline to be detected and the detection assembly are lowered into the box body through the lifting assembly, whether the bubble is generated in the pressure gauge and the box body or not is judged as a double detection phenomenon, and when the bubble appears at the joint between the pipeline to be detected and the detection assembly, a detector can quickly know the occurrence position and can accelerate the speed of reinstalling the pipeline to be detected, so that the problem is solved, and the misjudgment of the quality of the pipeline to be detected due to the installation problem is avoided.

(2) According to the utility model, the first supporting component and the second supporting component are adopted to adjust the placement height of the pipeline to be tested, so that the pipeline to be tested can be placed parallel to the central connecting line between the first sealing part and the second sealing part, when the pipeline to be tested is in interference sealing with the first sealing part and the second sealing part, the end part of the pipeline to be tested can be completely in interference sealing with the first sealing part and the second sealing part, the tightness between the pipeline to be tested and the detecting component is improved, the probability of repositioning the pipeline to be tested by a detecting person is reduced, and the working efficiency is improved.

Drawings

FIG. 1 is a schematic diagram of the overall structure of the present utility model;

FIG. 2 is a schematic diagram of the whole structure of the present utility model;

FIG. 3 is a schematic diagram of a part of the present utility model;

FIG. 4 is an exploded view of the present utility model;

FIG. 5 is a schematic diagram of a portion of a second embodiment of the present utility model;

FIG. 6 is an enlarged schematic view of portion A of FIG. 5;

fig. 7 is a schematic view showing the structure of the first sealing portion and the air charging hole in the present utility model.

Reference numerals: 1. a case; 2. a lifting assembly; 21. a lifting motor; 22. a first positioning plate; 23. a threaded rod; 24. a second positioning plate; 25. a guide rod; 3. a sliding member; 31. a slip plate; 32. a first slider; 33. a second slider; 3a, a sliding groove body; 4. an inflatable member; 41. an inflation end; 411. an inflator pump; 412. a pressure gauge; 413. a first mounting table; 42. a conflicting sealing end; 421. a second mounting table; 422. a second sealing part; 4221. a second interference plate; 4222. a second elastic sealing plate; 423. a support part; 5. a positioning piece; 51. a first driving motor; 52. a two-way threaded rod; 6. a first sealing part; 61. a first interference plate; 62. a first elastic sealing plate; 7. an air filling hole; 8. a first support assembly; 81. a mounting plate; 82. a cylinder; 83. a support block; 84. a guide plate; 8a, clamping grooves; 9. and a second support assembly.

Detailed Description

The present utility model will be described in further detail with reference to examples and drawings, but embodiments of the present utility model are not limited thereto.

As shown in fig. 1, a pressure pipeline gas tightness detection device for building engineering, including box 1, lifting unit 2, detection component, wherein, lifting unit 2 sets up on box 1, and the transmission is connected between detection component and the lifting unit 2, lifting unit 2 drive detection component goes up and down along the direction of height of box 1, the pipeline that awaits measuring is installed on detection component, and in this embodiment, deposit aqueous solution in box 1, drive pipeline that awaits measuring and detection component descend to box 1 through lifting unit 2, make aqueous solution surpass the pipeline that awaits measuring, can be the observed in a visual way and whether install the required degree of sealing between pipeline that awaits measuring and the detection component, and, when the junction between pipeline that awaits measuring and the detection component appears the bubble, the position that the detection personnel can know the emergence fast, and can accelerate the speed of reinstalling the pipeline that awaits measuring, solve the problem, avoid because the quality of installation problem and carry out the erroneous judgement of pipeline that awaits measuring.

The detection assembly comprises a sliding part 3, an inflating part 4 and a positioning part 5, wherein the sliding part 3 is connected with the lifting assembly 2 in a transmission manner, the lifting assembly 2 is used for controlling the sliding part 3 to ascend or descend along the height direction of the box body 1, the inflating part 4 is arranged on the sliding part 3, the positioning part 5 is fixedly arranged on the sliding part 3, the positioning part 5 is connected with the inflating part 4 in a transmission manner, the positioning part 5 drives the inflating assembly to slide along the arrangement direction of the sliding part 3, so that a pipeline to be detected is in interference sealing with the inflating part 4, and the tightness of the pipeline to be detected and the inflating part 4 is ensured.

Referring to fig. 2-4, in this embodiment, the sliding piece 3 includes a sliding plate 31, a first sliding block 32 and a second sliding block 33, the sliding plate 31 is disposed in the box 1, the first sliding block 32 and the second sliding block 33 are respectively disposed at two ends of the sliding plate 31, the first sliding block 32 and the second sliding block 33 are respectively in sliding fit with the sliding plate 31, specifically, a longitudinal section of the sliding plate 31 is in a T-shaped configuration, sliding groove bodies 3a in sliding fit with the sliding plate 31 are formed at bottoms of the first sliding block 32 and the second sliding block 33, the sliding plate 31 is disposed in the sliding groove bodies 3a, and the first sliding block 32 and the second sliding block 33 can slide along a setting direction of the sliding plate 31.

In this embodiment, the inflatable member 4 includes an inflatable end 41 and an abutting sealing end 42, the inflatable end 41 and the abutting sealing end 42 are respectively disposed at two ends of the sliding member 3, specifically, the inflatable end 41 is fixedly disposed at the top of the first sliding block 32, the abutting sealing end 42 is fixedly disposed at the top of the second sliding block 33, and when the first sliding block 32 and the second sliding block 33 move, the inflatable end 41 and the abutting sealing end 42 are driven to gradually approach or separate from each other, so that the pipe to be tested is clamped between the inflatable end 41 and the abutting sealing end 42.

The inflation end 41 includes an inflator 411, a pressure gauge 412, and a first mounting table 413, where the first mounting table 413 is fixedly disposed at the top of the first sliding block 32, the inflator 411 is fixedly disposed on the first mounting table 413, the pressure gauge 412 is communicated with the inflator 411, and is used for detecting real-time pressure in a pipeline to be detected, and a first sealing portion 6 is formed on one side of the inflator 411, which is close to the second sliding block 33, and is used for abutting against and sealing a port of the pipeline to be detected.

In this embodiment, the first sealing portion 6 includes a first abutting plate 61 and a first elastic sealing plate 62, the first abutting plate 61 is fixedly disposed at the air outlet end of the inflator 411, the first elastic sealing plate 62 is detachably and fixedly disposed at one side of the first abutting plate 61 away from the inflator 411, as shown in fig. 7, the first elastic sealing plate 62 may be detachably and fixedly disposed at the first abutting plate 61 by adopting a clamping structure, and of course, the first elastic sealing plate 62 and the first abutting plate 61 may be fixed by adopting a bolt fixing manner and other detachable fixing manners, and an air inflation hole 7 communicated with the air outlet end of the inflator 411 is formed in the first elastic sealing plate 62 and the first abutting plate 61 in a penetrating manner, and when the channel of the pipeline to be tested is fixedly installed, the channel of the pipeline to be tested is communicated with the air inflation hole 7, so that the channel of the pipeline to be tested can be normally inflated.

The abutting sealing end 42 comprises a second mounting table 421, a second sealing portion 422 and a supporting portion 423, the second mounting table 421 is fixedly arranged at the top of the second sliding block 33, the second sealing portion 422 is fixedly arranged at the top of the second mounting table 421, and the second sealing portion 422 and the first sealing portion 6 are oppositely arranged, wherein the second sealing portion 422 comprises a second abutting plate 4221 and a second elastic sealing plate 4222, the second abutting plate 4221 is fixedly arranged at the top of the second mounting table 421, the second elastic sealing plate 4222 is detachably and fixedly arranged on one side, close to the first sealing portion 6, of the second abutting plate 4221, and abutting sealing between two ends of a pipeline to be detected and the first elastic sealing plate 62 and the second elastic sealing plate 4222 can be ensured when the air tightness of the pipeline to be detected is detected.

The supporting part 423 is fixedly arranged on one side, close to the inflation end 41, of the second sealing part 422 and is used for supporting a pipeline to be tested, so that the pipeline to be tested can be placed parallel to a central connecting line between the first sealing part 6 and the second sealing part 422, and a supporting groove body used for supporting and clamping the pipeline to be tested is formed at the top of the supporting part 423, so that the pipeline to be tested can be placed conveniently.

The locating piece 5 is connected with the inflation end 41 and the abutting sealing end 42 in a transmission manner respectively, and is used for driving the inflation end 41 and the abutting sealing end 42 to synchronously move in the opposite direction, so that two ends of a pipeline to be tested respectively abut against the inflation end 41 and the abutting sealing end 42, wherein the locating piece 5 comprises a first driving motor 51 and a bidirectional threaded rod 52, the first driving motor 51 is fixedly arranged on one side of the sliding plate 31, the bidirectional threaded rod 52 is connected with a rotating shaft of the first driving motor 51 in a transmission manner, two ends of the bidirectional threaded rod 52 are respectively in threaded fit with the first sliding block 32 and the second sliding block 33, threads adopted at two ends of the bidirectional threaded rod 52 are reversely arranged, the first sliding block 32 and the second sliding block 33 can move in the opposite direction, the first driving motor 51 drives the first sliding block 32 and the second sliding block 33 to synchronously move in the opposite direction, the pipeline to be tested between the first sliding block 32 and the second sliding block 33 is clamped, two ends of the pipeline to be tested are respectively urged to abut against the first elastic sealing plate 62 and the second elastic sealing plate 4222, and the experimental error is guaranteed, and the experimental error is reduced.

In this embodiment, in order to ensure that the pipe to be tested can be placed along the central connecting line parallel to the first sealing portion 6 and the second sealing portion 422, therefore, the sliding plate 31 is located between the first sliding block 32 and the second sliding block 33 and is provided with the first supporting component 8, wherein the first supporting component 8 comprises a mounting plate 81, an air cylinder 82, supporting blocks 83 and a guide plate 84, the mounting plate 81 is arranged at the top of the sliding plate 31, the two guide plates 84 are respectively arranged at two sides of the mounting plate 81, the supporting blocks 83 are arranged between the two guide plates 84, the guide plates 84 and the supporting blocks 83 are in sliding fit, one end of the air cylinder 82 is fixedly connected with the mounting plate 81, the other end of the air cylinder 82 is fixedly connected with the bottom of the supporting blocks 83, and a clamping groove 8a for supporting the pipe to be tested is formed at the top of the supporting blocks 83.

The pipeline to be tested is placed in the clamping groove 8a, the guide plate 84 is moved along the setting direction of the sliding plate 31, the pipeline to be tested can be in a balanced state under the condition of not receiving external force, the height of the pipeline to be tested is adjusted through the air cylinder 82, the channel of the pipeline to be tested and the inflating hole 7 are located on the same axis, the inflating pump 411 is guaranteed to inflate the pipeline to be tested, the first sliding block 32 and the second sliding block 33 are driven by the first driving motor 51 in the locating piece 5 to gradually approach, two ends of the pipeline to be tested are respectively in abutting sealing with the first elastic sealing plate 62 and the second elastic sealing plate 4222, accordingly, two end parts of the pipeline to be tested are guaranteed to be in complete abutting sealing with the first elastic sealing plate 62 and the second elastic sealing plate 4222, the probability of repositioning the pipeline to be tested by a detector is reduced, and working efficiency is accelerated.

In this embodiment, in order to further improve the installation efficiency of the pipe to be tested, therefore, one side of the first sliding block 32, which is close to the second sliding block 33, is provided with the second supporting component 9, the second supporting component 9 is consistent with the first supporting component 8 in structure and function, which is not described herein, and by adopting the first supporting component 8 and the second supporting component 9, the placing height of the pipe to be tested is adjusted, so that the pipe to be tested can be placed parallel to the central connecting line between the first sealing portion 6 and the second sealing portion 422, thereby ensuring that when the pipe to be tested is in interference sealing with the first sealing portion 6 and the second sealing portion 422, the end of the pipe to be tested can be completely in interference sealing with the first sealing portion 6 and the second sealing portion, improving the tightness between the pipe to be tested and the detecting component, reducing the probability of repositioning the pipe to be tested by the detecting personnel, and accelerating the working efficiency.

Lifting component 2 includes elevator motor 21, first locating plate 22, threaded rod 23, second locating plate 24, guide bar 25, first locating plate 22, the fixed top that sets up in box 1 of second locating plate 24, and set up respectively in the both sides of box 1, elevator motor 21 is fixed to be set up on first locating plate 22, threaded rod 23 is connected with elevator motor 21's pivot transmission, and threaded rod 23 runs through first locating plate 22 in proper order, slide behind plate 31 and is connected with box 1's bottom rotation, threaded rod 23 and slide between plate 31, threaded fit between guide bar 25 runs through in slide plate 31 setting, and both ends respectively with box 1's bottom, fixed connection between second locating plate 24, when the pipeline that awaits measuring is installed in inflation end 41 and conflict seal end 42, drive threaded rod 23 through elevator motor 21, make the relative rotation between slide plate 31 and slide plate 31, make pipeline and detection component that await measuring and detection component's the water passing surface, whether the junction through real-time observation pipeline and detection component produces the bubble, thereby judge whether pipeline and detection component's bottom, whether can also carry out the accuracy of course, whether the accuracy of the test can be improved in the test case, the accuracy of test can be carried out as the test case, further accuracy and the test case, the water tightness of test case, and the test case.

The above description is only a preferred embodiment of the present utility model, and the protection scope of the present utility model is not limited to the above examples, and all technical solutions belonging to the concept of the present utility model belong to the protection scope of the present utility model. It should be noted that modifications and adaptations to the present utility model may occur to one skilled in the art without departing from the principles of the present utility model and are intended to be within the scope of the present utility model.

Claims

1. The utility model provides a pressure pipe gas tightness detection device for building engineering, its characterized in that includes box (1), lifting unit (2), detection subassembly, lifting unit (2) set up in on box (1), just detection subassembly with drive between lifting unit (2) are connected, lifting unit (2) drive detection subassembly is along the direction of height of box (1) goes up and down;

the detection assembly comprises a sliding part (3), an inflating part (4) and a positioning part (5), wherein the sliding part (3) is connected with the lifting assembly (2) in a transmission mode, the inflating part (4) is arranged on the sliding part (3), the positioning part (5) is fixedly arranged on the sliding part (3), the positioning part (5) is connected with the inflating part (4) in a transmission mode, the inflating part (4) comprises an inflating end (41) and an abutting sealing end (42), the inflating end (41) and the abutting sealing ends (42) are respectively arranged at two ends of the sliding part (3), the positioning part (5) is respectively connected with the inflating end (41) in a transmission mode between the abutting sealing ends (42) and used for driving the inflating end (41) to perform synchronous reverse movement between the abutting sealing ends (42), and two ends of a pipeline to be detected are respectively abutted against the inflating end (41) and the abutting sealing ends (42).

2. The pressure pipeline air tightness detection device for constructional engineering according to claim 1, wherein the sliding piece (3) comprises a sliding plate (31), a first sliding block (32) and a second sliding block (33), the first sliding block (32) and the second sliding block (33) are respectively arranged at two ends of the sliding plate (31), and the first sliding block (32) and the second sliding block (33) are respectively in sliding fit with the sliding plate (31).

3. The pressure pipeline air tightness detection device for construction engineering according to claim 2, wherein the air charging end (41) comprises an air charging pump (411), a pressure gauge (412) and a first mounting table (413), the first mounting table (413) is fixedly arranged at the top of the first sliding block (32), the air charging pump (411) is fixedly arranged on the first mounting table (413), the pressure gauge (412) is communicated with the air charging pump (411) and is used for detecting real-time pressure in the pipeline to be detected, and a first sealing part (6) is formed on one side, close to the second sliding block (33), of the air charging pump (411) and is used for abutting against a port of the pipeline to be detected.

4. A pressure pipeline air tightness detection device for construction engineering according to claim 3, wherein the abutting sealing end (42) comprises a second mounting table (421), a second sealing part (422) and a supporting part (423), the second mounting table (421) is fixedly arranged at the top of the second sliding block (33), the second sealing part (422) is fixedly arranged at the top of the second mounting table (421), the second sealing part (422) and the first sealing part (6) are oppositely arranged, and the supporting part (423) is fixedly arranged at one side, close to the air charging end (41), of the second sealing part (422) and is used for supporting a pipeline to be detected, so that the pipeline to be detected can be placed parallel to a central connecting line between the first sealing part (6) and the second sealing part (422).

5. The pressure pipeline air tightness detection device for construction engineering according to claim 4, wherein the positioning piece (5) comprises a first driving motor (51) and a bidirectional threaded rod (52), the first driving motor (51) is fixedly arranged on one side of the sliding plate (31), the bidirectional threaded rod (52) is in transmission connection with a rotating shaft of the first driving motor (51), two ends of the bidirectional threaded rod (52) are respectively in threaded fit with a first sliding block (32) and a second sliding block (33), the first driving motor (51) drives the first sliding block (32) and the second sliding block (33) to perform synchronous opposite movement, and a pipeline to be detected between the first sliding block (32) and the second sliding block (33) is clamped.

6. The pressure pipeline air tightness detection device for constructional engineering according to claim 5, wherein the sliding plate (31) is located between the first sliding block (32) and the second sliding block (33) is provided with a first supporting component (8), the first supporting component (8) comprises a mounting plate (81), a cylinder (82), supporting blocks (83) and a guide plate (84), the mounting plate (81) is arranged at the top of the sliding plate (31), the two guide plates (84) are respectively arranged at two sides of the mounting plate (81), the supporting blocks (83) are arranged between the two guide plates (84), the guide plates (84) are in sliding fit with the supporting blocks (83), one end of the cylinder (82) is fixedly connected with the mounting plate (81), the other end of the cylinder is fixedly connected with the bottom of the supporting blocks (83), and a clamping groove (8 a) for supporting a pipeline to be detected is formed at the top of the supporting blocks (83).

7. The pressure pipeline air tightness detection device for construction engineering according to claim 6, wherein a second supporting component (9) is arranged on one side, close to the second sliding block (33), of the first sliding block (32), and the second supporting component (9) is consistent with the first supporting component (8) in structure and function.

8. The pressure pipeline air tightness detection device for construction engineering according to claim 7, wherein the lifting assembly (2) comprises a lifting motor (21), a first positioning plate (22), a threaded rod (23), a second positioning plate (24) and a guide rod (25), the first positioning plate (22) and the second positioning plate (24) are fixedly arranged at the top of the box body (1) and are respectively arranged at two sides of the box body (1), the lifting motor (21) is fixedly arranged on the first positioning plate (22), the threaded rod (23) is in transmission connection with a rotating shaft of the lifting motor (21), the threaded rod (23) sequentially penetrates through the first positioning plate (22) and then is in rotation connection with the bottom of the box body (1), the threaded rod (23) is in threaded fit with the second positioning plate (31), and the guide rod (25) penetrates through the top of the box body (31) and is respectively fixedly connected with the bottom of the box body (1) and the second positioning plate (24).