CN112393031B

CN112393031B - Pipeline maintenance method

Info

Publication number: CN112393031B
Application number: CN202011282439.XA
Authority: CN
Inventors: 刘烨华; 杨进新; 张奇; 王惠萍; 石维新; 孙海龙; 王帆; 丁艳辉; 吕兵; 王东黎
Original assignee: Beijing Hanjian Water Conservancy And Hydropower Engineering Co ltd; BEIJING INSTITUTE OF WATER
Current assignee: Beijing Hanjian Water Conservancy And Hydropower Engineering Co ltd; BEIJING INSTITUTE OF WATER
Priority date: 2020-11-16
Filing date: 2020-11-16
Publication date: 2022-08-02
Anticipated expiration: 2040-11-16
Also published as: CN112393031A

Abstract

The invention relates to the technical field of maintenance of large pipelines, in particular to a pipeline maintenance method. The pipeline (1) comprises an inner pipe (2) and a pipe sleeve (3) sleeved outside the inner pipe (2), the pipe sleeve (3) has defects, and the maintenance method comprises the following steps: s1: dividing the pipe sleeve (3) into a plurality of sockets (7) along the length direction of the pipeline (1), and replacing the sockets (7) in batches, thereby completing the maintenance of the pipeline (1). According to the maintenance method of the pipeline, the pipe sleeve is divided into a plurality of sockets to be replaced in batches, so that the maintenance cost of the pipeline is reduced.

Description

Pipeline maintenance method

Technical Field

The invention relates to the technical field of maintenance of large pipelines, in particular to a pipeline maintenance method.

Background

At present, in large diversion works in China, more and more works using water pipes are used, for example, circular pipes such as a PCCP (prestressed concrete cylinder pipe), a PCP (prestressed concrete cylinder pipe), a glass sand inclusion pipe, a reinforced concrete pipe and a steel pipe are common water pipes in the prior art. However, due to the defects of design and construction quality, improper operation management and the like, pipe explosion phenomena occur in a plurality of water diversion and adjustment projects, and the safe operation of the water conveying pipeline is seriously threatened.

Most of PCCP pipe burst is caused by the defects that the annular prestress steel strand is wound on the core of the high-strength concrete pipe, the wire is broken and the like, and pipelines with serious defects need to be replaced so as to eliminate potential safety hazards. The existing pipeline replacement technology generally adopts a replacement method, specifically, a defective pipeline is directly and integrally replaced, however, a pipe core of the defective pipeline is usually intact, and the replacement method is adopted, so that the pipe core of the pipeline is wasted, and the maintenance cost is high.

Disclosure of Invention

The invention aims to solve the problem of high cost caused by maintenance of a pipeline through a replacement method in the prior art, and provides a pipeline maintenance method, which reduces the maintenance cost of the pipeline by dividing a pipe sleeve into a plurality of sockets to replace in batches.

In order to achieve the above object, the present invention provides a maintenance method of a pipeline including an inner pipe and a pipe sleeve fitted around the outer pipe of the inner pipe, the pipe sleeve having a defect, the maintenance method including: s1: dividing the pipe sleeve into a plurality of sockets along the length direction of the pipeline, and replacing the sockets in batches so as to finish the maintenance of the pipeline.

Optionally, in step S1, the pipe sleeve is divided into n sockets, where n is greater than or equal to 5, and the n sockets are numbered 1, 2, … …, (n-1), and n in sequence along the length direction of the pipe sleeve; and replacing the 2 nd socket and the (n-1) th socket, replacing the 1 st socket and the nth socket, and finally replacing other sockets of the pipe sleeve between the 2 nd socket and the (n-1) th socket.

Optionally, a plurality of said sockets are of uniform length.

Optionally, the pipe sleeve includes a reinforcing wire wound around the inner pipe and a protective layer covering the reinforcing wire, and in step S1, the specific process of replacing the single socket is as follows:

s11: sequentially removing the protective layer and the reinforcing wires of the socket;

s12: and sequentially installing the reinforcing wires and the protective layer of the socket.

Optionally, in step S12, when the reinforcing wire is installed, the reinforcing wire is wound outside the inner tube of the socket, and then a tensioning operation is performed on the reinforcing wire through a tensioning device to apply a prestress to the reinforcing wire.

Optionally, in step S11, when detaching the reinforcing wire, the reinforcing wire at the socket is cut and then pulled away.

Optionally, the pipeline is an underground pipeline, and the maintenance method further includes step S0 before step S1, specifically: the pipe is excavated and exposed.

Optionally, in step S0, the included angle between the centers of the exposed portions of the pipes is 240 ° to 270 °, and the exposed portions are symmetrically distributed with respect to the vertical longitudinal section of the pipe.

Optionally, the maintenance method further includes a step S2 after the step S1, specifically: a reinforcing structure is built to secure the pipe.

Alternatively, in step S2, a mold is first disposed on one side of the pipe in the radial direction, and the opening wall of the mold is abutted against the outer circumferential surface of the pipe sleeve to form a mold cavity together with the pipe sleeve, and concrete is poured into the mold cavity for molding to form the reinforcing structure.

According to the technical scheme, the pipeline maintenance method reduces the pipeline maintenance cost by replacing the pipe sleeve. The large pipeline is taken as an example, generally, the pipeline is formed by connecting a plurality of pipelines end to end, when one pipeline has a defect, if the whole pipe sleeve of the pipeline is directly dismounted, the inner pipe of the pipeline is caused to sink and the like, and then the joint of the pipeline and the adjacent pipeline has the defects of bending deformation and the like.

Drawings

FIG. 1 is a schematic structural view of a pipe according to the present invention, wherein the pipe casing is divided into a plurality of sockets;

fig. 2 is a schematic structural diagram of a pipe provided by the present invention, wherein the matching relationship between the mold and the pipe is shown.

Description of the reference numerals

1. A pipeline; 2. an inner tube; 3. pipe sleeve; 4. a mold; 5. a mold cavity; 6. wood bracing; 7. a socket.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

The invention provides a maintenance method of a pipeline, as shown in figures 1 and 2, the pipeline 1 comprises an inner pipe 2 and a pipe sleeve 3 sleeved outside the inner pipe, the pipe sleeve 3 has defects, and the maintenance method comprises the following steps: s1: the pipe sleeve 3 is divided into a plurality of sockets 7 along the length direction of the pipeline 1, and the plurality of sockets 7 are replaced in batches, so that the maintenance of the pipeline 1 is completed. The pipeline may be in various reasonable forms, for example, may be a water pipeline, specifically, may be any one of circular pipes such as a PCCP pipe (prestressed steel cylinder concrete pipe), a PCP pipe (prestressed steel concrete pipe), a glass sand inclusion pipe, a reinforced concrete pipe, a steel pipe, and the like; other pipes with a diameter of 2m or more may be used.

According to the technical scheme, the maintenance method of the pipeline provided by the invention reduces the maintenance cost of the pipeline 1 by replacing the pipe sleeve 3. Taking a large-scale pipeline as an example, the pipeline is generally formed by connecting a plurality of pipelines end to end, when one pipeline has a defect, if the whole pipe sleeve of the pipeline is directly removed, the inner pipe of the pipeline is caused to sink and the like, and further the joint of the pipeline and the adjacent pipeline has the defects of bending deformation and the like.

Further, in step S1, the pipe sleeve 3 is divided into n sockets 7, where n is greater than or equal to 5, and the n sockets 7 are numbered 1, 2, … …, (n-1), n in sequence along the length direction of the pipe sleeve 3; the 2 nd socket and the (n-1) th socket are replaced, the 1 st socket and the nth socket are replaced, the other sockets between the 2 nd socket and the n-1 th socket of the pipe sleeve 3 are replaced, and the mode of replacing the sockets 7 in batches is adopted, so that the pipe sleeve can be replaced smoothly in situ, and the safe maintenance of the pipeline is realized. Taking the pipe sleeve 3 in fig. 1 divided into 5 sockets as an example (i.e., at this time, n is 5), the 5 sockets are the 1 st socket, the 2 nd socket, the 3 rd socket, the 4 th socket and the 5 th socket in turn from left to right, when the pipe sleeve 3 of the pipeline 1 is replaced, the 2 nd socket and the 4 th socket are replaced first, then the 1 st socket and the 5 th socket are replaced, and finally the 3 rd socket is replaced.

Furthermore, the lengths of the plurality of sockets 7 are consistent, so that the pipe sleeves can be replaced according to a unified standard, and the safe maintenance of the pipeline is facilitated.

Further, the pipe sleeve 3 includes a reinforcing wire wound around the inner pipe 2 and a protective layer coated around the reinforcing wire, and in step S1, the specific process of replacing the single socket 7 is as follows: s11: sequentially removing the protective layer and the reinforcing wires of the socket 7; s12: the reinforcing wires and the protective layer of the socket 7 are sequentially installed, so that smooth replacement of the socket is conveniently completed. Among them, the above-mentioned defects of the pipe sleeve may be various types of defects, for example, a case where the protective layer is broken, or the like, or a case where the reinforcing wire is broken, and the like, to cause a loss of prestress. In addition, the protective layer is in various reasonable forms, for example, a concrete protective layer, etc.; the reinforcing wire is in various reasonable forms, for example, a steel strand and the like, when the steel strand is stripped, a small tool can be used for stripping, each socket is stripped from top to bottom, specifically, stripping is carried out according to the sequence from the top of the pipe to the bottom of the pipe through the circumference of the pipe, when the pipe is stripped to a central angle of 90 degrees (the pipe is symmetrically distributed by taking the bottom of the pipe as a symmetry axis), annular stripping is carried out from one side of the lowest point of the pipeline to the other side of the lowest point of the pipeline until the annular direction is through. It is worth mentioning that before removing the socket, the following preparation should be performed, specifically: firstly, calibrating a jack and an oil pressure gauge in a matched manner, performing linear regression on calibration data, and calculating a regression equation; verifying whether the specifications and the quantities of the construction machines and the materials conform to actual requirements or not; and selecting a steel strand blanking site and erecting a construction platform, then making a blanking length mark on the selected flat hardening site, retesting the blanking length, peeling the steel strands at two ends for blanking, and padding color strip cloth in the site of the storage area before blanking to prevent the epoxy steel strands from being damaged.

Further, in step S12, when the reinforcing wire is installed, the reinforcing wire is wound outside the inner pipe 2 of the socket 7, and then a tensioning operation is performed on the reinforcing wire through a tensioning device to apply a prestress to the reinforcing wire, so that the inner pipe can be reinforced by the reinforcing wire, and the overall strength of the pipeline is improved. Wherein, the reinforcing wire can be in various winding forms, for example, the reinforcing wire can be wound around the circumferential direction of the inner tube; preferably, the reinforcing wire may be spirally wound around the outer circumferential surface of the inner tube, which is advantageous in improving the overall strength of the pipe. Wherein the tensioning device can be in various forms, for example, a tensioning machine suitable for steel strands; specifically, when a partitioned ring-through steel strand bundle is adopted, each anchorage device is annularly provided with 2 steel strands, each steel strand surrounds a pipeline needing to be reinforced with the PCCP for two circles, the blanked steel strand is pulled to the bottom of the pipeline and is penetrated and wound for two circles from the bottom, sealing pipes are arranged at two ends of the steel strand and are fixed on the anchorage device through clamping pieces, and the working length is reserved to be not less than 0.9 m; after the strand pulling operation of the steel strand bundle is completed, according to the integrity degree of the outer wall of the pipe body, tensioning is carried out according to a design tension force control value of 5-10%, the steel strands are pre-tensioned, the spacing of the steel strands is adjusted uniformly before pre-tensioning, the arrangement spacing of the steel strands is determined according to the integrity degree of a PCCP pipeline to be reinforced, operation pressure calculation is carried out, 4 jacks are controlled by 2 oil pumps to realize synchronous tensioning, after the steel strands are tensioned, a stress analysis test is carried out to protect an anchorage device, and a reserved working length of a tensioning end of each steel strand is sheared before an anchorage device protective cover is installed (for example, the residual end head needs to be 5cm longer than an anchor head after shearing); it is worth noting that when the jack is installed and pre-tightened, the extender is determined to be aligned with the anchorage device, and is coordinated with the jack tool limiting groove, when the pre-tightening operation is performed, the force value is controlled to pre-tighten according to the designed stage, the tensioning assembly is checked to be abnormal, the pressure is slowly increased at a constant speed, and the time is suspended for 3-5min before the tensioning force is increased once. In addition, after the inner tube 2 is fastened by the prestressed reinforcing wire, the protective layer is coated outside the reinforcing wire; specifically, after the steel strand bundle is tensioned, the anchorage device is covered and fixed by a protective cover, polysulfide sealant is poured into the protective cover, and finally a mold is manufactured to pour the sealed anchorage device so as to form a protective layer outside the steel strand bundle, thereby ensuring the complete protection and sealing of the steel strand. In addition, in order to realize the fixed installation of the anchorage device, a longitudinal line can be drawn in the middle of the pipe top, two sides of the pipe top in the circumferential direction are respectively extended outwards by 20 degrees, namely, the highest point of the pipe top is respectively moved downwards by 20 degrees towards the left side and the right side to draw two parallel lines extending along the axial direction, so as to obtain two anchoring area distribution axes, and then the anchorage device is installed at the corresponding position on the distribution axis drawn by the pipeline according to different types of the anchorage device; specifically, the backing plate can be firstly bonded and positioned at the corresponding position of the pipeline by using the structural adhesive, and then the anchor backing plate is fixed by using the modified epoxy adhesive patch (the time for the anchor to reach the allowable strength is not less than 48h), so that the fixed installation of the anchor is completed.

Further, in step S11, when detaching the reinforcing wire, the reinforcing wire at the socket 7 is cut first, and then the reinforcing wire is pulled away, so that the operation difficulty of detaching the reinforcing wire is simplified, and the detaching operation is simpler and more convenient. Wherein, a long-handle angle grinder can be adopted to cut the reinforcing wires; and (5) pulling the reinforcing wire away by using tensioning equipment.

Further, the pipeline 1 is an underground pipeline 1, and the maintenance method further includes step S0 before step S1, specifically: the pipe 1 is excavated and exposed, and the operation is simpler. Wherein, the excavation operation is carried out by adopting a conventional excavator, and the loading is matched by a loader. It is worth noting that a small excavator is adopted to excavate the narrow area on the pipe side from the lower part to the platform, the pipe base is excavated to 120 degrees on the lower part of the pipeline, then the step-by-step manual excavation is carried out, and a long arm excavator can be adopted to excavate the middle area of the pipeline; it can be understood that each excavation depth meets the requirement of circular penetration, but the manual excavation of the pipe bottom construction needs a certain working surface, the pipe bottom base layer of the adjacent area is disturbed during excavation, the groove edges at the two sides can be supported by the baffle plates to reduce the collapse of the pipe bottom sand gravel materials of the adjacent area, the manual excavation of the pipe base, the steel wire drawing-off and the mortar protective layer peeling can be circularly performed, and in order to reduce the mortar collapse, the steel wire drawing-off and the mortar protective layer peeling-off processes can also be alternately performed at the same time interval after the manual excavation is finished.

In order to prevent the pipeline from rolling under the action of self weight and damaging other pipelines connected to two sides of the pipeline, in step S0, the included angle of the circle centers of the exposed parts of the pipeline 1 is 240-270 degrees, and the exposed parts are symmetrically distributed about the vertical longitudinal section of the pipeline 1, so that the included angle of the circle centers of the buried parts is correspondingly set to be 120-90 degrees, and the pipeline is provided with necessary supporting function through the buried parts, thereby ensuring that the damaged pipe sleeve of the pipeline is smoothly replaced. It can be understood that after the pipe sleeve is replaced, soil is backfilled and then backfilled and compacted.

Further, the maintenance method further includes a step S2 after the step S1, specifically: and a reinforcing structure is built to fix the pipeline 1, so that the backfilling compactness of soil bodies near the pipeline is ensured.

As shown in fig. 2, in step S2, a mold 4 is first disposed on one side of the pipe 1 in the radial direction, and the opening wall of the mold 4 abuts against the outer circumferential surface of the socket 3 to form a mold cavity 5 together with the socket 3, and concrete is poured into the mold cavity 5 for molding to form the reinforcing structure, which is simple and low-cost. It will be appreciated that the gate of the mould cavity 5 may take various forms, for example, it may be provided as a top gate, i.e. at the gap between the top of the mould and the outer peripheral surface of the sleeve 3. Further, in order to ensure smooth pouring and molding of concrete, the outer side of the mold 4 can be fixedly supported by a wood brace 6. In addition, a single mold 4 may be used in the present application, wherein the single mold may abut against a portion of the pipe sleeve shown in fig. 2 in the axial direction, and of course, may abut against the entire section of the pipe sleeve in the axial direction; preferably, a plurality of molds 4 can be used, for example, 5 molds are used and arranged in sequence along the axial direction of the pipe sleeve (with a gap between two adjacent molds), each mold is correspondingly abutted against each socket on the pipe sleeve shown in fig. 1, and after the concrete forming process is completed, the molds corresponding to the 2 nd socket, the 3 rd socket and the 4 th socket shown in fig. 1 are removed.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications may be made to the technical solution of the invention, and in order to avoid unnecessary repetition, various possible combinations of the invention will not be described further. Such simple modifications and combinations should be considered within the scope of the present disclosure as well.

Claims

1. A method for maintaining a pipeline, the pipeline (1) comprising an inner pipe (2) and a pipe sleeve (3) fitted over the inner pipe (2), the pipe sleeve (3) having a defect, the method comprising:

s1: dividing the pipe sleeve (3) into a plurality of sockets (7) along the length direction of the pipeline (1), and replacing the sockets (7) in batches so as to finish the maintenance of the pipeline (1);

in step S1, the pipe sleeve (3) is divided into n sockets (7), wherein n is more than or equal to 5, and the n sockets (7) are numbered as 1, 2, … …, (n-1) and n in sequence along the length direction of the pipe sleeve (3); the 2 nd and the n-1 st of the sockets are replaced, the 1 st and the n-th of the sockets are replaced, and finally the other sockets of the pipe sleeve (3) between the 2 nd and the n-1 st of the sockets are replaced.

2. Method for maintaining a pipeline according to claim 1, characterized in that a plurality of said sockets (7) are of uniform length.

3. The method for maintaining a pipeline according to claim 1 or 2, wherein the pipe sleeve (3) comprises a reinforcing wire wound around the inner pipe (2) and a protective layer coated on the reinforcing wire, and in step S1, the specific process of replacing the single socket (7) is as follows:

s11: sequentially removing the protective layer and the reinforcing wires of the socket (7);

s12: and sequentially installing the reinforcing wires and the protective layer of the socket (7).

4. The method for maintaining a pipeline according to claim 3, wherein the reinforcing wire is wound outside the inner pipe (2) of the socket (7) when the reinforcing wire is installed, and then the reinforcing wire is subjected to a tensioning operation by a tensioning device to prestress the reinforcing wire at step S12.

5. The method for maintaining a pipe according to claim 3, wherein in step S11, when detaching the reinforcing wire, the reinforcing wire at the socket (7) is cut and then pulled away.

6. The method for maintaining a pipeline according to claim 1, wherein the pipeline (1) is an underground pipeline (1), and the method further comprises, before step S1, step S0, in particular: excavating and exposing the pipeline (1).

7. The method for maintaining a pipeline according to claim 6, wherein in step S0, the included angle of the circle center of the exposed part of the pipeline (1) is 240-270 degrees, and the exposed part is symmetrically distributed about the vertical longitudinal section of the pipeline (1).

8. The method for maintaining a pipeline according to claim 1, further comprising a step S2 after the step S1, specifically: -building a reinforcement structure to fix the pipe (1).

9. The pipe maintenance method according to claim 8, wherein in step S2, a mold (4) is first disposed on one side of the pipe (1) in the radial direction, and an opening wall of the mold (4) is abutted against an outer circumferential surface of the socket (3) to form a mold cavity (5) together with the socket (3), and concrete is poured into the mold cavity (5) for molding to form the reinforcing structure.