Branch line installation device and method without pipeline transmission interruption

Abstract

The invention belongs to the technical field of non-transmission pipeline construction, and particularly relates to a non-transmission pipeline branch line installation device and method, and the method comprises the following steps: 1) respectively welding a main line pipe fitting and a balance hole pipe fitting on the outer circumference of a main line pipeline, and testing the pressure; (2) a branch pipeline valve and a branch pipeline are installed on the branch pipe fitting, and strength pressure testing is completed; (3) pressure tappers are installed on the main line pipe fitting and the balance hole pipe fitting correspondingly, and branch line through holes and balance holes are formed in the main line pipe fitting correspondingly; (4) the sandwich valve is closed, and the under-pressure tapper on the trunk line flange is dismounted; mounting a plugging device on the sandwich valve, and backfilling the plugging block into the trunk pipe fitting under pressure by the plugging device; 5, the plugging device and the sandwich valve are removed, a blind plate is installed on a main line flange, and meanwhile, installation of the balance hole plugging block and the balance hole blind plate is completed. Branch line increasing construction is rapidly conducted when the pipeline does not stop conveying, the number of devices used for construction is small, and the construction technology is simple and efficient.

Description

Technical Field

[0001] The invention belongs to the technical field of non-stop pipeline construction, and in particular relates to a pipeline non-stop branch line installation device and an installation method. Background Art

[0002] Traditional single-side single-seal non-stop plugging construction adds branch line technology, such as Figure 1 As shown, six tee pipe fittings (i.e., two bypass tee pipe fittings 21, two plugging tee pipe fittings 22, and two bladder hole tee pipe fittings 23) and two balance hole pipe fittings 24 need to be welded on the trunk pipeline 1, and relevant equipment is installed to complete the pressure tapping operation. The bypass tee pipe fitting 21 is used to connect the bypass pipeline 3, and then the trunk pipeline 1 that needs to add the branch pipeline 4 is partially blocked by the plugging tee pipe fitting 22, the bladder hole tee pipe fitting 23 and the isolation bladder 25. After the trunk pipeline 1 that needs to add the branch line is emptied and replaced and qualified, the pipe is cut off, and the reducing tee 26 is welded at the pipe cut off, and the branch pipeline 4 with the ball valve 41 installed is welded at the outlet of the reducing tee 26. Then take out the isolation bag 25, complete the installation of the blind plate of the bag hole three-way pipe fitting 23; remove the blockage of the main pipeline 1, install the plug and the blocking blind plate on the blocking three-way pipe fitting 22, and complete the installation of the block and the blind plate of the balance hole pipe fitting 24 at the same time; remove the bypass pipeline; install the plug and the blocking blind plate on the bypass three-way pipe fitting 21; finally, complete the connection operation of the branch pipeline 4, etc.

[0003] The conventional single-side single-sealing non-stop plugging construction process for adding a branch line has the following technical problems: the process is too complicated, there are many construction equipment involved, the construction time is long, the site occupies a large area, the impact on the pipeline transportation task is large, and the construction risk is high, and there are many tees left over from the construction. In view of the special application scenarios of adding branch line projects, the present invention designs a pipeline non-stop branch line installation device and installation method, which only requires a pressurized hole opening operation on the main pipeline 1 to complete the main pipeline adding branch line operation. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and propose a pipeline non-stop branch line installation device and installation method, which can quickly add branch line construction while the pipeline is non-stop and requires less equipment and a simple and efficient construction process.

[0005] The technical solution adopted by the present invention is as follows: A pipeline non-stop transmission branch line installation device, comprising: Reducer pipe fittings: including trunk pipe fittings that can be sealed and fixedly connected to the trunk pipeline, branch pipe fittings that are arranged on the outer circumference of the trunk pipe fittings and communicate with the inner cavity of the trunk pipe fittings, and trunk flanges that are fixedly connected to the trunk pipe fittings; Branch pipeline valve: installed on the branch pipeline or branch pipe fittings; A clamping valve, which is detachably fixedly connected to the trunk flange and is used to open and close the trunk pipe fittings; A pressure hole opener, which is detachably fixedly connected to the clamping valve and is used to open a hole under pressure in the trunk pipeline; A plugging block may be embedded in the trunk pipe fitting and used to seal the inner cavity of the trunk pipe fitting; A plugging device, which is detachably fixedly connected to the clamping valve and is used to place the plugging block in the inner cavity of the trunk pipe; A blind plate, which can be fixedly connected to the main line flange; A balancing hole pipe fitting is fixedly connected to the trunk pipeline and communicated with the inner cavity of the trunk pipeline, and is used to communicate with the plug to balance the pressure difference between the inside and outside of the trunk pipeline.

[0006] Preferably, a locking ring groove and a sealing ring groove are respectively provided on the upper and lower outer circumferences of the plug block, and a sealing ring is embedded in the sealing ring groove; a locking through hole connected to the inner cavity of the main line flange is provided on the outer circumference, and a locking bolt or a sealing bolt can be threadedly connected in the locking through hole, and the locking bolt can be clamped in the locking ring groove.

[0007] Preferably, a connecting rod is fixedly connected to the lower end surface of the plugging block, and a saddle plate is fixedly connected to the lower end of the connecting rod. The saddle plate can be embedded in the branch line through hole, and the inner cavity of the main pipeline is connected to the inner cavity of the main pipe above the saddle plate.

[0008] Preferably, the saddle plate matches the branch through hole opened on the main pipeline, a saddle plate through hole is opened on the saddle plate, and the inner cavity of the main pipeline is connected with the inner cavity of the main pipe above the saddle plate through the saddle plate through the saddle plate through hole.

[0009] Preferably, the outer diameter of the saddle plate is smaller than the inner diameter of the branch line through hole.

[0010] Preferably, the saddle plate through holes are provided in plurality and the inner diameter of the saddle plate through holes is larger than the inner diameter of the branch line pipeline.

[0011] Preferably, the lower end opening of the trunk pipe fitting is a saddle-shaped structure matching the trunk pipeline, and the lower end opening of the trunk pipe fitting is welded to the outer circumference of the trunk pipeline.

[0012] Preferably, an upper pipe fitting is integrally formed at the lower end of the trunk pipe fitting, and a lower pipe fitting is arranged opposite to the upper pipe fitting. The inner diameters of the upper pipe fitting and the lower pipe fitting are the same as the outer diameter of the trunk pipeline and a gap is left between the lower end surface of the upper pipe fitting and the upper end surface of the lower pipe fitting.

[0013] A method for installing a pipeline non-stop branch line comprises the following steps: Step 1: Weld the trunk pipe fittings and the balancing hole pipe fittings to the outer circumference of the trunk pipeline respectively, and perform pressure testing on the trunk pipe fittings and the balancing pipe fittings; Step 2: Install a branch pipeline valve on the branch pipeline fitting, and install a branch pipeline on the branch pipeline valve; or fix the branch pipeline with the branch pipeline valve installed on the branch pipeline fitting; Step 3: Install a clamp valve on the main flange of the main pipe fitting, and install a pressure hole opener on the clamp valve to open a branch through hole on the main pipeline; install a pressure hole opener on the balance hole pipe fitting and open a balance hole on the main pipeline; Step 4: close the clamp valve and remove the pressurized hole opener on the trunk flange; install a plugging device on the clamp valve on the trunk flange, and the plugging device fills the plugging block back into the trunk pipe under pressure; Step 5: Remove the plug and the clamp valve in turn, install the blind plate on the main flange, and complete the installation of the balancing hole plug and the balancing hole blind plate at the same time.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a pipeline non-stop branch line installation device and installation method. Compared with the traditional single-side single-seal non-stop branch line adding process, the method only needs to complete the opening operation of a variable diameter pipe fitting to complete the branch line adding project, eliminating the complicated construction processes such as bypass project construction, plugging construction, nitrogen replacement and pipe cutting and connection, reducing the number of equipment involved in the construction, saving construction period, reducing construction risks, improving the construction efficiency of the branch line installation project, and solving the practical problems of the branch line adding project. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] 1. Trunk pipeline, 11. Branch through hole, 21. Bypass tee pipe fitting, 22. Blocking tee pipe fitting, 23. Cap hole tee pipe fitting, 24. Balance hole pipe fitting, 25. Isolation capsule, 26. Reducer tee, 3. Bypass pipeline, 4. Branch pipeline, 41. Ball valve, 42. Branch pipeline valve, 5. Reducer pipe fitting, 51. Trunk pipe fitting, 52. Branch pipe fitting, 53. Trunk flange, 531. Locking through hole, 532. Locking bolt, 54. Branch flange, 55. Upper pipe fitting, 56. Lower pipe fitting, 6. Plug, 61. Locking ring groove, 62. Sealing ring groove, 63. Sealing ring, 64. Connecting plate, 65. Connecting rod, 66. Saddle plate, 661. Saddle plate through hole, 7. Blind plate.

[0016] Figure 1 A schematic diagram of the branch line process structure is added to the traditional single-side single-seal non-stop plugging construction.

[0017] Figure 2 A branch line construction principle diagram is added to the present invention.

[0018] Figure 3 Schematic diagram of the connection structure of the reducer pipe fitting, the plugging block and the blind plate of Example 1 of the present invention.

[0019] Figure 4 It is a schematic diagram of the cross-sectional structure of the reducer pipe fitting, the plugging block and the blind plate of Example 1 of the present invention.

[0020] Figure 5 This is a schematic diagram of the first-view connection structure of the blocking block, connecting rod, and saddle plate of Example 1 of the present invention.

[0021] Figure 6 This is a schematic diagram of the connection structure of the plugging block, connecting rod and saddle plate from a second perspective in Example 1 of the present invention.

[0022] Figure 7 This is a schematic structural diagram of a reducer pipe according to Embodiment 2 of the present invention.

[0023] Figure 8 This is a schematic structural diagram of a reducer pipe according to Example 3 of the present invention.

[0024] Fig. 9 This is a schematic structural diagram of a reducer pipe according to Example 4 of the present invention. DETAILED DESCRIPTION

[0025] In order to explain the advantages of the present invention clearly, the following is further described in detail in conjunction with specific embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Example 1

[0026] A device for opening a branch line without stopping the pipeline includes a reducer 5, a branch line pipeline valve 42, a clamp valve, a pressure hole opener, a plug block 6, a plugging device, a blind plate 7 and a balance hole pipe fitting 24. Among them, the branch line pipeline valve 42 can be a ball valve, and the clamp valve, the pressure hole opener, the plugging device and the balance hole pipe fitting 24 are all existing technologies, and the specific structure and working principle are not repeated here.

[0027] See also Figure 2 , 3 As shown in Figures 4, 5 and 6, the reducer 5 includes a trunk pipe fitting 51 which can be sealably welded to the trunk pipeline 1, a branch pipe fitting 52 which is integrally formed on the outer circumference of the trunk pipe fitting 51 and communicates with the inner cavity of the trunk pipe fitting 51, a trunk flange 53 and a branch flange 54 which are respectively welded on the trunk pipe fitting 51 and the branch pipe fitting 52, a branch pipeline valve 42 is installed on the branch flange 54 of the branch pipe fitting 52, and the branch pipeline 4 is installed on the branch pipeline valve 42; or a branch pipeline 52 with a branch pipeline valve 42 welded to the branch pipe fitting 52; in this embodiment, for the convenience of installation, a branch flange 54 is provided on the branch pipe fitting 52 so as to be docked with the branch pipeline valve 42 for installation.

[0028] The clamp valve is detachably mounted on the trunk flange 53 by means of fastening bolts and is used to open and close the trunk pipe 51; A pressure hole opener, which is detachably mounted on the clamping valve by fastening bolts and is used to open a hole in the trunk pipeline 1 under pressure; The plugging block 6 can be embedded in the trunk pipe 51 and used to seal the inner cavity of the trunk pipe 51. In addition, it also includes a balancing hole plugging block for plugging the balancing hole pipe 24. Since the balancing hole plugging block is a prior art, it will not be described in detail in this specification. The plugging device is detachably mounted on the clamping valve by fastening bolts and is used to place the plugging block 6 in the inner cavity of the trunk pipe 51; The blind plate 7 is fixedly mounted on the main line flange 53 by tightening bolts; The balancing hole pipe fitting 24 is welded on the trunk pipeline 1 and communicated with the inner cavity of the trunk pipeline 1, and is used to communicate with the plug to balance the pressure difference between the inside and outside of the trunk pipeline 1, so as to facilitate the opening of the clamp valve.

[0029] Specifically, the outer circumference of the plugging block 6 is respectively provided with a locking ring groove 61 and a sealing ring groove 62, and a sealing ring 63 is embedded in the sealing ring groove 62. The sealing ring 63 is made of elastic material and its outer diameter is slightly larger than the inner diameter of the trunk pipe 51, so as to seal the trunk pipe 51. The outer circumference of the trunk flange 53 is symmetrically provided with locking through holes 531 connected to its inner cavity, and a locking bolt 532 or a plugging bolt (not shown in the figure) can be threadedly connected in the locking through hole 531. When the plugging block 6 needs to be fixed in the trunk pipe 51, the locking bolt 532 can be clamped in the locking ring groove 61; when the plugging block 6 is not fixed in the trunk pipe 51, the plugging bolt is threadedly connected in the locking through hole 531 to seal the inner cavity of the trunk flange 53.

[0030] Furthermore, in this embodiment, a connecting plate 64 is bolted and fixedly connected to the lower end surface of the plugging block 6, a connecting rod 65 is vertically fixedly connected to the connecting plate 64, a saddle plate 66 is welded to the lower end of the connecting rod 65, and the saddle plate 66 can be embedded in the branch through hole 11, and the inner cavity of the trunk pipeline 1 is connected to the inner cavity of the trunk pipe fitting 51 above the saddle plate 66. The saddle plate 66 matches the branch through hole 11 opened on the trunk pipeline 1, that is, the saddle plate 66 can be a saddle plate removed when the trunk pipeline 1 is opened under pressure, and when the plugging block 6 is locked, the lower end surface of the saddle plate 66 is flush with the inner wall of the trunk pipeline 11. A saddle plate through hole 661 is opened on the saddle plate 66, and the inner cavity of the trunk pipeline 1 is connected to the inner cavity of the trunk pipe fitting 51 above the saddle plate 66 through the saddle plate through hole 661. Furthermore, a plurality of saddle plate through holes 661 are provided, and the inner diameter of the saddle plate through holes 661 is larger than the inner diameter of the branch pipe 4, so that the medium in the trunk pipe 1 can smoothly enter the branch pipe 4. By providing a plurality of saddle plate through holes 661, the resistance of the medium entering the branch pipe 4 can be reduced, and the medium transporting efficiency of the branch pipe 4 can be improved while the stability of the medium transporting can be improved.

[0031] On the basis of the above-mentioned saddle plate 66 structure, the outer diameter of the saddle plate 66 can be smaller than the inner diameter of the branch line through hole 11, that is, the saddle plate removed when the main pipeline 1 is opened under pressure is cut and processed. Preferably, the outer diameter of the saddle plate 66 is 30 mm smaller than the aperture of the branch line through hole 11 opened by the hole opening machine on the main pipeline, so as to facilitate the smooth backfilling of the plug 6.

[0032] Since the trunk pipeline needs to be descaled and desilted regularly, in order to prevent the descaling and desilting device from entering the branch line through hole 11 and getting stuck when passing through the branch line through hole 11 opened on the trunk pipeline, that is, when the trunk pipeline 1 is cleaned by ball cleaning, the saddle plate 66 plays a conductive role.

[0033] In addition, in this embodiment, in order to facilitate welding of the trunk pipe 51 to the trunk pipeline 1, an upper pipe 55 is integrally formed at the lower end of the trunk pipe 51, and a lower pipe 56 is arranged opposite to the upper pipe 55. The inner diameters of the upper pipe 55 and the lower pipe 56 are the same as the outer diameter of the trunk pipeline 1, and a gap is left between the lower end surface of the upper pipe 55 and the upper end surface of the lower pipe 56 for straight seam welding. In this embodiment, one branch pipe 52 is provided, but of course multiple branches may be provided. Example 2

[0034] See also Figure 7As shown, this embodiment 2 is another structural design of the reducer 5 based on the embodiment 1, that is, in order to simplify the structure of the reducer 5, the upper pipe fitting 55 and the lower pipe fitting 56 are not provided at the lower part of the trunk pipe fitting 51, but the lower end opening of the trunk pipe fitting 51 is designed as a saddle-shaped structure matching the trunk pipeline 1, and the lower end opening of the trunk pipe fitting 51 is welded to the outer circumference of the trunk pipeline 1. Example 3

[0035] See also Figure 8 As shown, this embodiment 3 is another structural design of the reducer 5 based on the embodiment 1, that is, a plurality of branch pipes 52 can be arranged on the trunk pipe 51, such as two in this embodiment. Example 4

[0036] See also Fig. 9 As shown, this embodiment 4 is another structural design of the reducer 5 based on the embodiment 3, that is, in order to simplify the structure of the reducer 5, the upper pipe fitting 55 and the lower pipe fitting 56 are not provided at the lower part of the trunk pipe fitting 51, but the lower end opening of the trunk pipe fitting 51 is designed as a saddle-shaped structure matching the trunk pipeline 1, and the lower end opening of the trunk pipe fitting 51 is welded to the outer circumference of the trunk pipeline 1.

[0037] A method for installing a pipeline non-stop transmission branch line using any one of the above-mentioned embodiments 1 to 4 comprises the following steps: Step 1: Determine the opening point according to the branch line position, peel off the anti-corrosion layer of the trunk pipeline 1, weld the trunk pipe fitting 51 and the balance hole pipe fitting 24 on the outer circumference of the trunk pipeline 1 respectively, and perform pressure test on the trunk pipe fitting 51 and the balance pipe fitting 24; Step 2: Install the branch pipeline valve 42 on the branch pipeline flange 54, and install the branch pipeline 4 on the branch pipeline valve 42; Step 3: Install a clamp valve on the trunk flange 53 of the trunk pipe fitting 51, and install a pressure hole opener on the clamp valve, open the clamp valve, and use the pressure hole opener to open the branch through hole 11 on the trunk pipeline 1; install the corresponding pressure hole opener on the balance hole pipe fitting 24 and open a balance hole on the trunk pipeline 1; at this time, if the branch pipeline valve 42 in step 2 is in an open state, the medium in the trunk pipeline 1 enters the trunk pipe fitting 51, the branch pipe fitting 52 and the branch pipeline 4 through the branch through hole, and the branch pipeline 4 is in a connected state; if the branch pipeline valve 42 in step 2 is in a closed state, the medium in the trunk pipeline 1 enters the trunk pipe fitting 51 and the branch pipe fitting 52 through the branch through hole. This operation can, to a certain extent, avoid a large amount of medium in the trunk pipeline 1 from entering the branch pipeline 4, causing the pressure hole opener and the reducer 5 to be subjected to a large impact force.

[0038] Step 4: Close the clamp valve and remove the pressurized hole opener on the trunk flange 53; install a plug on the clamp valve on the trunk flange 53, connect the plug with the balance hole pipe fitting 24, open the clamp valve, and the plug will backfill the plug block 6 together with the connecting plate 64, the connecting rod 65, and the saddle plate 66 into the trunk pipe fitting 51 under pressure; take out the sealing bolt from the locking through hole 531 on the trunk flange 53, and screw the locking bolt 532 into the locking through hole 531 and clamp it in the locking ring groove 61. At this time, the lower end surface of the saddle plate 66 is flush with the inner wall of the trunk pipeline 1; Step 5: Remove the plug and the clamp valve in sequence, install the blind plate 7 on the main flange 53, and complete the installation of the balancing hole plug and the balancing hole blind plate at the same time. The structure and installation of the balancing hole plug and the balancing hole blind plate are all existing technologies; Afterwards, anti-corrosion work can be carried out on the reducer 5 and the balance hole pipe 24. After passing the electric spark test, the work pit is backfilled as required, and the construction method of opening the pipeline non-stop branch line is completed.

[0039] In practical applications, the pipeline non-stop transmission branch line opening device and its construction method have the following advantages: 1. The investment in machinery and equipment involved in the construction has been reduced by more than 70%; 2. The construction personnel input is only 50% of that of the traditional process; 3. The investment in construction materials has been reduced by 70%. Only one set of reducer pipe fittings needs to be customized and the investment in auxiliary materials has also been reduced accordingly; 4. Only one construction site is required, which reduces the number of standardized construction site layouts; 5. After the technological innovation, a number of traditional construction processes were reduced, and the construction time was shortened by 50%; 6. Due to the optimization of construction procedures, the construction safety factor is correspondingly improved and the safety risk of on-site construction is reduced.

[0040] The above specific implementation methods and embodiments are specific support for the technical idea of ​​applying a pipeline non-stop branch line installation device and installation method proposed by the present invention, and cannot be used to limit the protection scope of the present invention. Any equivalent changes or equivalent modifications made on the basis of this technical solution in accordance with the technical idea proposed by the present invention still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A pipeline non-stop branch line installation device, characterized by: include: Reducer pipe fittings: including trunk pipe fittings that can be sealed and fixedly connected to the trunk pipeline, branch pipe fittings that are arranged on the outer circumference of the trunk pipe fittings and communicate with the inner cavity of the trunk pipe fittings, and trunk flanges that are fixedly connected to the trunk pipe fittings; Branch pipeline valve: installed on the branch pipeline or branch pipe fittings; A clamping valve, which is detachably fixedly connected to the trunk flange and is used to open and close the trunk pipe fittings; A pressure hole opener, which is detachably fixedly connected to the clamping valve and is used to open a hole under pressure in the trunk pipeline; A plugging block may be embedded in the trunk pipe fitting and used to seal the inner cavity of the trunk pipe fitting; A plugging device, which is detachably fixedly connected to the clamping valve and is used to place the plugging block in the inner cavity of the trunk pipe; A blind plate, which can be fixedly connected to the main line flange; A balancing hole pipe fitting is fixedly connected to the trunk pipeline and communicated with the inner cavity of the trunk pipeline, and is used to communicate with the plug to balance the pressure difference between the inside and outside of the trunk pipeline.

2. According to claim 1, a pipeline non-stop branch line installation device is characterized by: The outer circumference of the plug block is respectively provided with a locking ring groove and a sealing ring groove, and a sealing ring is embedded in the sealing ring groove; the outer circumference of the main line flange is provided with a locking through hole connected to its inner cavity, and a locking bolt or a sealing bolt can be threadedly connected in the locking through hole, and the locking bolt can be clamped in the locking ring groove.

3. According to claim 1, a pipeline non-stop branch line installation device is characterized by: A connecting rod is fixedly connected to the lower end surface of the plugging block, and a saddle plate is fixedly connected to the lower end of the connecting rod. The saddle plate can be embedded in the branch line through hole, and the inner cavity of the main pipeline is connected to the inner cavity of the main pipe above the saddle plate.

4. According to claim 3, a pipeline non-stop branch line installation device is characterized by: The saddle plate matches the branch line through hole opened on the main pipeline. A saddle plate through hole is opened on the saddle plate. The inner cavity of the main pipeline is connected with the inner cavity of the main pipe above the saddle plate through the saddle plate through the saddle plate through hole.

5. According to claim 4, a pipeline non-stop transmission branch line installation device is characterized in that: The outer diameter of the saddle plate is smaller than the inner diameter of the branch line through hole.

6. According to claim 4, a pipeline non-stop transmission branch line installation device is characterized in that: The saddle plate through holes are provided in plurality and the inner diameter of the saddle plate through holes is larger than the inner diameter of the branch line pipeline.

7. A pipeline non-stop branch line installation device according to any one of claims 1 to 6, characterized in that: The lower opening of the trunk pipe fitting is a saddle-shaped structure matching the trunk pipeline, and the lower opening of the trunk pipe fitting is welded to the outer circumference of the trunk pipeline.

8. A pipeline non-stop branch line installation device according to any one of claims 1 to 6, characterized in that: The lower end of the trunk pipe is integrally formed with an upper pipe, and a lower pipe is arranged opposite to the upper pipe. The inner diameters of the upper and lower pipes are the same as the outer diameter of the trunk pipeline, and a gap is left between the lower end surface of the upper pipe and the upper end surface of the lower pipe.

9. A method for installing a pipeline non-stop branch line, characterized in that: The steps include: Step 1: Weld the trunk pipe fittings and the balancing hole pipe fittings to the outer circumference of the trunk pipeline respectively, and perform pressure testing on the trunk pipe fittings and the balancing pipe fittings; Step 2: Install a branch pipeline valve on the branch pipeline fitting, and install a branch pipeline on the branch pipeline valve; or fix the branch pipeline with the branch pipeline valve installed on the branch pipeline fitting; Step 3: Install a clamp valve on the main flange of the main pipe fitting, and install a pressure hole opener on the clamp valve to open a branch through hole on the main pipeline; install a pressure hole opener on the balance hole pipe fitting and open a balance hole on the main pipeline; Step 4: close the clamp valve and remove the pressurized hole opener on the trunk flange; install a plugging device on the clamp valve on the trunk flange, and the plugging device fills the plugging block back into the trunk pipe under pressure; Step 5: Remove the plug and the clamp valve in turn, install the blind plate on the main flange, and complete the installation of the balancing hole plug and the balancing hole blind plate at the same time.

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