Construction method for adding tee joint to existing large-diameter pipeline

Abstract

The application belongs to the technical field of pipeline construction, and particularly discloses a construction method for adding a tee joint to a large-diameter existing pipeline, which comprises the following steps: preparing a sleeve according to the size and shape of the existing pipeline; sleeving the sleeve on the existing pipeline and filling the gap between the existing pipeline and the sleeve; cutting a hole in the sleeve and connecting the added pipeline to form a tee joint; opening a manhole on the added pipeline; temporarily closing the valve of the existing pipeline, emptying the conveying object in the existing pipeline; entering the added pipeline from the manhole, chiseling and dismounting the designed dismounting section of the existing pipeline; and closing the manhole, and the construction of the new tee joint is completed. After the existing pipeline is wrapped with a sleeve to form a tee joint, the wrapped section of the existing pipeline is dismounted, the production and installation of the tee joint can be completed without cutting off the existing pipeline, the pipeline is cut off only temporarily in the last connecting stage, the time for cutting off the existing pipeline is delayed, the construction time is effectively reduced, the existing pipeline can be effectively protected from damage, the construction quality is improved, and the leakage problem at the connection position is reduced.

Description

Technical Field

[0001] This invention belongs to the field of pipeline construction technology, and in particular relates to a construction method for adding a tee to an existing large-diameter pipeline. Background Technology

[0002] Pipeline construction projects are mostly used in major public welfare projects such as water transportation, oil transportation, and sewage discharge. Simultaneously, with the comprehensive acceleration of water conservancy infrastructure construction in my country, more and more major water conservancy projects are starting construction, involving a large number of new, expanded, and renovated pipelines. These projects often require the addition of new joints, i.e., tees, to existing pipelines, while the existing pipelines are often still transporting materials and cannot be interrupted for extended periods. The conventional construction method for adding tees involves cutting off the existing pipeline and then connecting the new tee to the existing pipeline by welding or using a socket joint, while the existing pipeline continues to perform its corresponding transportation tasks.

[0003] Welding installation presents challenges due to differences in materials between existing pipelines and newly constructed tees, leading to connection difficulties and inconsistent quality. Furthermore, welding large-diameter tees requires extensive work time, and the existing pipeline supply cannot be interrupted for extended periods. Socket-type installations, on the other hand, have stringent requirements regarding the material and shape of existing pipelines. For deformed or non-standard diameter pipes, it is difficult to prepare sockets and joints in advance, resulting in prolonged construction periods.

[0004] Both of the above solutions carry a high risk of leakage at the joints due to design and construction quality issues. Therefore, there is an urgent need for a construction method that minimizes the time existing pipelines are disconnected and reduces the duration of pipeline interruptions, while also ensuring effective connection at the tee joints of large-diameter pipelines, improving construction quality, and reducing the risk of leakage at the joints. Summary of the Invention

[0005] The purpose of this invention is to provide a construction method for adding a tee to an existing large-diameter pipeline, so as to solve the problems of long construction time and leakage risk caused by quality problems in the existing technology of welding installation or plug-in installation.

[0006] To achieve the above objectives, the technical solution of the present invention is: a construction method for adding a tee to an existing large-diameter pipeline, comprising:

[0007] Sleeve preparation: The sleeve is prepared according to the size and shape of the existing pipeline; the length of the sleeve is longer than the length of the designed demolition section of the existing pipeline;

[0008] Installing a sleeve: Place the sleeve onto the existing pipe and fill the gap between the existing pipe and the sleeve;

[0009] Connecting the sleeve and the existing pipeline: Cut a hole in the sleeve and connect it to the new pipeline to form a tee; and open a manhole in the new pipeline;

[0010] Dismantling the existing pipeline designed for demolition: Temporarily close the existing pipeline valves and empty the materials transported in the existing pipeline; enter the new pipeline through the manhole, chisel and dismantle the existing pipeline designed for demolition; seal the manhole, and complete the construction of the new tee.

[0011] Further, prepare the casing: prepare the casing according to the size and shape of the existing pipeline; the specific steps are: excavate a test pit at the location where a tee is designed to be added to the existing pipeline, measure the external size and shape of the existing pipeline, and make the casing according to the measured external size and shape.

[0012] Furthermore, the entire casing is divided into at least two pipe segments along its length, and each pipe segment is divided into upper and lower halves along its central axis.

[0013] Further, install the sleeve: Place the sleeve onto the existing pipe and fill the gap between the existing pipe and the sleeve; the specific steps are: place the upper and lower halves of the pipe segment onto the existing pipe, and weld the joints of the upper and lower halves to form a ring; fill the gap between the existing pipe and the pipe segment with sealant, and then cast a semi-encasing support to support the pipe segment; install all pipe segments according to the above method, and then weld the pipe segments together to form a complete sleeve; the length of each semi-encasing support is consistent with the length of the corresponding pipe segment.

[0014] Further, install the sleeve: Place the sleeve onto the existing pipe and fill the gap between the existing pipe and the sleeve; the specific steps are as follows: Place the upper and lower halves of the pipe segment onto the existing pipe, and weld the joints of the upper and lower halves to form a ring; then cast a semi-encasing support to support the pipe segment; install all pipe segments according to the above method, and then weld the pipe segments together to form a complete sleeve; finally, use sealant to fill the gap between the existing pipe and the sleeve; the length of each semi-encasing support is consistent with the length of the corresponding pipe segment.

[0015] Furthermore, the inner diameter of the sleeve is 1.5-2.5cm larger than the inner diameter of the existing pipeline; the entire sleeve is divided into 2-3 pipe segments along its length; and the sleeve is at least 1m longer on each side than the designed demolition section of the existing pipeline.

[0016] Furthermore, the area of ​​the corresponding pipe segment wrapped by the semi-enclosed pier shall not exceed half and the height shall not exceed 20cm.

[0017] Furthermore, oil hemp and micro-cement grout are used for filling.

[0018] Furthermore, the manholes were sealed by welding with the same material as the newly added pipelines.

[0019] The beneficial effects of this technical solution are as follows: by using a sleeve to form a tee on the existing pipeline and then dismantling the wrapped section of the existing pipeline, the tee can be fabricated and installed without cutting off the existing pipeline. It is only briefly cut off during the final connection stage. This technical solution can effectively solve the problems of connection difficulties caused by different materials (especially applicable when the existing pipe is made of fragile material and the new pipeline is made of steel) and long construction time for large-diameter pipes. It delays the cutting off of the existing pipeline, effectively reduces construction time, and at the same time effectively protects the existing pipeline from damage, improves construction quality, and reduces leakage at the connection. Attached Figure Description

[0020] Figure 1 This is a flowchart of a construction method for adding a tee to an existing large-diameter pipeline according to the present invention;

[0021] Figure 2 This is a construction drawing of a construction method for adding a tee to an existing large-diameter pipeline according to the present invention. Detailed Implementation

[0022] The following detailed description illustrates the specific implementation method:

[0023] The reference numerals in the accompanying drawings of the instruction manual include: 1. Existing pipeline, 2. Designed demolition section, 3. Pipe segment, 4. Semi-enclosed anchor, 5. Sleeve, 6. Sealant, 7. Manhole, 8. New pipeline.

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] The basic implementation examples are as follows: Figure 1-2 The following is a construction method for adding a tee to an existing large-diameter pipeline, including the following steps:

[0026] Step S1: Prepare the sleeve 5: Prepare the sleeve 5 according to the size and shape of the existing pipeline 1; the specific steps are as follows: excavate a test pit at the location where the tee is designed to be added to the existing pipeline 1 (depending on the material of the existing pipeline 1, a certain length of the existing pipeline 1 will be excavated and effectively supported by materials such as steel sections), measure the external dimensions and shape of the excavated existing pipeline 1 (use a tape measure and steel wire to measure its shape and dimensions), and make the sleeve 5 according to the measured external dimensions and shape; the length of the sleeve 5 is longer than the length of the designed demolition section 2 of the existing pipeline 1, specifically, the two sides of the sleeve 5 are at least 1m longer than the two sides of the designed demolition section 2 of the existing pipeline 1, and the inner diameter of the sleeve 5 at all points is 1.5-2.5cm larger than the inner diameter of the existing pipeline 1; the method of making the sleeve 5 is as follows: divide the entire sleeve 5 into at least two pipe segments 3 (preferably 2-3 segments) along the length direction of the sleeve 5. If the existing pipeline 1 is not long, it is not necessary to make segments. Each pipe segment 3 is divided into upper and lower halves along the central axis; the sleeve 5 is made of steel.

[0027] Step S2: Install sleeve 5: Sleeve sleeve 5 onto the existing pipe 1 and fill the gap between the existing pipe 1 and sleeve 5; the first method is: sleeve the upper and lower halves of pipe segment 3 onto the existing pipe 1 (specifically, lower half first, then upper half), and weld the joints of the upper and lower halves to form a ring; use sealant 6 to fill the gap between the existing pipe 1 and pipe segment 3 (specifically, hemp and quick-drying micro-cement grout can be used for filling), and then use concrete to cast semi-encasing blocks 4 to support pipe segment 3; install all pipe segments 3 according to the above method, and then weld the pipe segments 3 together to form a complete sleeve 5; the length of each semi-encasing block 4 is consistent with the length of the corresponding pipe segment 3;

[0028] The second method is as follows: The upper and lower halves of pipe segment 3 are fitted onto the existing pipe 1 (specifically, the lower half is placed first, then the upper half), and the joints of the upper and lower halves are welded to form a ring; then, a semi-encasing anchor 4 is poured to support pipe segment 3; all pipe segments 3 are installed according to the above method, and then the pipe segments 3 are welded together to form a complete sleeve 5; finally, the gap between the existing pipe 1 and the sleeve 5 is filled with sealant 6 (specifically, hemp fiber and quick-drying micro-cement grout can be used for filling); the length of each semi-encasing anchor 4 is consistent with the length of the corresponding pipe segment 3; specifically, only the two sides of the sleeve 5 can be filled; this method is used as an example in this embodiment.

[0029] The area of ​​the corresponding pipe segment 3 wrapped by the semi-enclosed town pier 4 shall not exceed half and the height shall not exceed 20cm;

[0030] Step S3: Connect sleeve 5 and existing pipe 1: Cut a hole in sleeve 5 and connect the new pipe 8 to form a tee; and open a manhole 7 on the new pipe 8, the diameter of the manhole 7 being 80cm;

[0031] Step S4: Remove the existing pipeline 1 designed removal section 2: Temporarily close the valve of the existing pipeline 1 and empty the transported material in the existing pipeline 1; enter the new pipeline 8 through the manhole 7, chisel and dismantle the existing pipeline 1 designed removal section 2; weld and seal the manhole 7 with the same material as the new pipeline 8, and the construction of the new tee is completed.

[0032] The following is an example of a specific pipeline construction method:

[0033] In this embodiment, the existing pipe 1 is made of glass-reinforced sand pipe, and the newly added pipe 8 is made of steel pipe. The glass-reinforced sand pipe is of non-standard size and its pipe section has been deformed into a non-standard elliptical shape due to the pressure of the overlying soil. The planned length of the glass-reinforced sand pipe to be removed is 6m.

[0034] Excavation pits were dug at the locations where tees were added to the glass-filled sand pipe design (and the largest size part at that location was selected). The shape and size were measured using a tape measure and steel wire. The manufactured casing 5 was divided into 3 pipe segments 3. Each pipe segment 3 was divided into upper and lower halves. The middle pipe segment 3 was 4m long, and the remaining segments were 2m long.

[0035] First, install the lower half of the first pipe segment 3, then install the upper half. Next, use flat welding to form a complete pipe segment 3. Use sealant 6 to fill the gap between the existing pipe 1 and the pipe segment 3. Then, use C25 concrete to cast a semi-encasing support pier 4 to support the pipe segment 3. Install all pipe segments 3 using the above method, and then weld the pipe segments 3 together to form a complete sleeve 5. Alternatively, first install all pipe segments 3 onto the existing pipe 1, then weld the pipe segments 3 together to form a complete sleeve 5, and then fill the gap between the sleeve 5 and the existing pipe 1, filling only the two sides of the sleeve 5. This embodiment uses this method as an example.

[0036] When installing each pipe segment 3, pay attention to the installation position of each pipe segment 3, and ensure that the pipe segments 3 on both sides are 1m longer than the two sides of the existing pipe 1 designed to be removed segment 2.

[0037] Cut a hole in the sleeve 5 and weld the new pipe 8 to form a tee; and open a manhole 7 in the new pipe 8. Temporarily close the valve of the existing pipe 1 and empty the material transported in the existing pipe 1; enter the new pipe 8 through the manhole 7, chisel and dismantle the designed demolition section 2 of the existing pipe 1; weld the manhole 7 closed with the same material as the new pipe 8, and the construction of the new tee is completed.

[0038] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0039] The above descriptions are merely embodiments of the present invention. Commonly known structures and characteristics are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are aware of all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, under the guidance of this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention. These should also be considered within the scope of protection of the present invention, and will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A construction method for adding a tee to an existing large-diameter pipeline, characterized in that: include Sleeve preparation: The sleeve is prepared according to the size and shape of the existing pipeline. The specific steps are as follows: Excavate a test pit at the location where a tee is designed to be added to the existing pipeline, measure the external size and shape of the existing pipeline, and make the sleeve according to the measured external size and shape; the length of the sleeve is longer than the length of the section of the existing pipeline designed to be removed. Install the sleeve: Divide the entire sleeve into at least two pipe segments along its length, and divide each pipe segment into upper and lower halves along its central axis; fit the sleeve onto the existing pipeline and fill the gap between the existing pipeline and the sleeve. The specific steps are as follows: fit the upper and lower halves of the pipe segment onto the existing pipeline, and weld the joints of the upper and lower halves to form a ring; fill the gap between the existing pipeline and the pipe segment with sealant, and then cast a semi-encasing pier to support the pipe segment; install all pipe segments according to the above method, and then weld the pipe segments together to form a complete sleeve; each The length of each semi-encasing support is the same as the length of the corresponding pipe segment; or the sleeve is fitted onto the existing pipe and the gap between the existing pipe and the sleeve is filled. The specific steps are as follows: fit the upper and lower halves of the pipe segment onto the existing pipe, and weld the joints of the upper and lower halves to form a ring; then cast the semi-encasing support to support the pipe segment; install all pipe segments according to the above method, and then weld the pipe segments together to form a complete sleeve; finally, use sealant to fill the gap between the existing pipe and the sleeve; the length of each semi-encasing support is the same as the length of the corresponding pipe segment. Connecting the sleeve and the existing pipeline: Cut a hole in the sleeve and connect it to the new pipeline to form a tee; and open a manhole in the new pipeline; Dismantling the existing pipeline designed for demolition: Temporarily close the existing pipeline valves and empty the materials transported in the existing pipeline; enter the new pipeline through the manhole, chisel and dismantle the existing pipeline designed for demolition; seal the manhole, and complete the construction of the new tee.

2. The construction method for adding a tee to an existing large-diameter pipeline according to claim 1, characterized in that: The inner diameter of the sleeve is 1.5-2.5cm larger than that of the existing pipeline; the entire sleeve is divided into 2-3 pipe segments along its length; the sleeve is at least 1m longer on each side than the designed demolition section of the existing pipeline.

3. The construction method for adding a tee to an existing large-diameter pipeline according to claim 1, characterized in that: The area of ​​the corresponding pipe segment wrapped by the semi-enclosed pier shall not exceed half and the height shall not exceed 20cm.

4. The construction method for adding a tee to an existing large-diameter pipeline according to claim 1, characterized in that: Oil hemp and micro-cement grout were used for filling.

5. The construction method for adding a tee to an existing large-diameter pipeline according to claim 1, characterized in that: The manhole was sealed by welding with the same material as the newly added pipeline.

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