Well control pipeline online leaking stoppage device and using method thereof

Abstract

The invention discloses a well control pipeline online leaking stoppage device and a using method thereof. One end of an agent injection device is connected with a leaking stoppage clamp, and the other end of the agent injection device is connected with a pump. The two splicing pieces are spliced into a hollow column body, pipeline mounting holes are formed in the two splicing pieces in the axial direction, and the pipeline mounting holes are matched with the outer wall of a well control pipeline; a drainage hole and an injection agent hole are formed in the two splicing pieces in the radial direction, and the drainage hole and the injection agent hole are both communicated with the pipeline mounting hole; a drainage valve is arranged outside the drainage hole and is a one-way valve, and the agent injection hole is connected with an agent injection device. The agent injection device comprises an agent injection gun, and the agent injection gun can be filled with a sealant. The drainage hole and the drainage valve are arranged, during installation and leaking stoppage, the risk of on-line operation of personnel can be reduced, high-pressure liquid flows out of the drainage hole, the hydraulic injection agent pressure is adjusted in real time according to the pressure of a medium in a pipeline, the reasonable internal and external pressure difference is utilized, the pressure bearing range is widened, and the good sealing performance is achieved under the high pressure.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas exploration and development, and particularly relates to an online leak plugging device for a well control pipeline and a use method thereof. Background Art

[0002] As the depth of wells increases during the exploration and development of oil and gas fields, the formation pressure is getting higher and higher. In particular, the Tarim Oilfield is a major oil and gas exploration and development area in my country, with a large number of "three high wells". At present, the rated pressure of the high-pressure manifolds of the drilling and well control system commonly used in the Tarim Oilfield is 75MPa and 105MPa. In the process of high-pressure well drilling, oil testing, downhole operations, oil and gas production, etc., accidents such as failure of well control pipeline seals and pipeline punctures often occur due to high-pressure erosion and corrosion. In addition, during the on-site plugging of well control pipelines, there may be a situation where the upstream valve is not closed tightly. Therefore, there is an urgent need for an online plugging method for well control pipelines that can achieve online plugging under pressure and can withstand a pressure of up to 84MPa after plugging.

[0003] At present, the commonly used pressure sealing methods for pressurized pipeline plugging in the petrochemical field include top pressure plugging method, pressure bonding plugging method, flexible pressure plugging method, and clamp sealing method, but the pressure bearing capacity of these methods will not exceed 35MPa.

[0004] The Chinese patent application number is CN2018111087577, and the invention name is a non-welded pipeline plugging device and method. The method adopts a flexible pressure plugging method, wrapping expansion rubber and rubber sheets at the pipeline leakage position, installing inner molds and outer membranes on the outside, and then vulcanizing the rubber through a heating device to form a pressure-resistant rubber to achieve plugging. The pressure bearing capacity of this method has been improved compared with the traditional flexible pressure plugging method, but it is only applicable to oil pipelines with a pressure of 15 to 30 MPa. The T&TS solid-free liquid plugging agent technology currently used for wellbore plugging has a compressive strength of up to 70 MPa. Although it can withstand higher pressures, it requires a larger injection space, which will cause the fixture to be too large and cannot be installed in a confined space. At the same time, it requires a longer gel time, about 4 to 24 hours of construction time, and the gel requires a heating auxiliary device and precise temperature control. The design and operation are complex and the construction time is long. It is not suitable for emergency online pressure plugging conditions. Summary of the invention

[0005] In order to overcome the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide an online leak plugging device for well control pipelines and a method of using the same, so as to meet online emergency conditions and solve problems such as long construction time and limited space. The present invention combines solid sealing technology, multi-layer sealing structure and high-pressure injection process to provide an online emergency leak plugging method suitable for high-pressure well control pipelines, thereby providing a guarantee for well control safety.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] An online leak plugging device for a well control pipeline, comprising:

[0008] A leak-proof clamp, comprising two mutually connected parts;

[0009] An injection device, one end of which is connected to the leak-stopping fixture, and the other end of which is connected to a pump;

[0010] The two assembled parts are assembled into a hollow cylinder, and a pipeline installation hole is opened in the axial direction of the two assembled parts, and the pipeline installation hole cooperates with the outer wall of the well control pipeline; the two assembled parts are opened with a drainage hole and an injection hole in the radial direction, and the drainage hole and the injection hole are both connected with the pipeline installation hole; a drainage valve is arranged outside the drainage hole, and the drainage valve is a one-way valve, and the injection hole is connected with the injection device; the injection device includes an injection gun, and the sealant can be filled in the injection gun.

[0011] Optionally, a groove is provided in the pipeline installation hole of the assembly, and the groove is communicated with the injection hole.

[0012] Optionally, the injection device includes an injection nozzle, one end of which is connected to the injection hole, and the other end of which is connected to the injection gun.

[0013] Optionally, an injection valve is provided between the injection nozzle and the injection gun.

[0014] Optionally, an injection pressure display gauge is provided on the pipeline between the injection valve and the injection gun.

[0015] Optionally, the pump is a hydraulic oil pump, and the hydraulic oil pump is connected to the injection gun through a high-pressure oil pipe.

[0016] Optionally, a radial rubber pad is provided in the pipeline installation hole along the radial direction of the assembly piece, and an axial rubber pad is provided along the axial direction of the assembly piece.

[0017] Optionally, the number of the drainage hole and the number of the injection hole are both one, and the injection hole and the drainage hole are respectively opened on the two assembled parts.

[0018] Optionally, the sealant is made of a polymer composite pressure-resistant variable dielectric material.

[0019] A method for using an online leak plugging device for a well control pipeline comprises the following steps:

[0020] Open the drainage valve and install the plugging fixture and injection device at the leaking position of the well control pipeline;

[0021] Put solid sealant into the injection gun;

[0022] Close the drainage valve, start the pump remotely, and push the solid sealant into the plugging fixture through hydraulic oil;

[0023] Control the pressure of hydraulic oil to stimulate the high pressure sealing performance of solid sealant.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention can realize online installation under the condition of 3-5MPa leakage pressure of pipeline, and can meet the pressure bearing capacity of 84MPa. It can be used for online emergency plugging of well control pipeline straight pipe, flange connection, flange in valve, knob of internal spray tool, and puncture leakage. It can also be applied to emergency plugging of high-pressure pipelines with the same or similar media. The present invention is provided with drainage holes and drainage valves, which can reduce the danger of online operation of personnel during installation and plugging, and make high-pressure liquid flow out of the drainage holes. At the same time, since the drainage valve is a one-way valve, it can ensure the sealing performance and ensure that the puncture direction of the medium is controllable during the installation and operation of personnel, which reduces the installation resistance and improves the safety of personnel during operation. The pipeline installation hole of the present invention has a groove connected to the injection hole, which can ensure that the sealant enters the pipeline installation hole. The present invention adjusts the hydraulic injection pressure in real time according to the internal medium pressure of the pipeline, and uses a reasonable internal and external pressure difference to widen the pressure range. In this method, the plugging fixture is connected to the injection device, and an injection pressure gauge is installed. In cooperation with the pressure gauge of the well control pipeline system, the pressure in the well control pipeline and the injection cavity can be observed in real time, and the injection pressure can be automatically adjusted according to the pressure difference. The internal and external pressure difference is accurately utilized to achieve good sealing performance under higher pressure, thereby expanding the scope of application of this method.

[0026] Furthermore, the present invention adopts a solid sealant, which is suitable for various uneven workpiece surfaces of leaking pipelines. In the state of emergency rescue of drilling and well control, the leakage port of the well control pipeline is usually uneven due to crack leakage, the leakage medium composition is complex, and the leakage port is often not clean. The existing method uses liquid injection materials to achieve sealing through surface adsorption force, and the surface of the leaking pipeline requires a higher surface roughness and a relatively clean surface state. The polymer composite sealant used in the present invention is solid, and the pressure provided by the hydraulic oil pump allows the solid sealant to reshape in the limited space of the fixture, fill the sealing space of the fixture, and self-stimulate the seal through high pressure. It does not rely on the adsorption force between the sealant material and the leaking pipeline, and does not require high surface roughness and cleanliness of the leaking pipeline. It can adapt very well to the online sealing and plugging of well control pipelines.

[0027] The solid sealant combined with the hydraulic thrust shaping method adopted in the present invention shortens the time it takes for the sealant to develop strength. Solid sealants are in solid form under both normal pressure and high pressure conditions. Hydraulic pressure is used to send the solid sealant into the fixture cavity for re-plasticization, and the strength of the sealant can be stimulated with the help of hydraulic pressure. For liquid sealants, heating and solidification are required, and a longer gel time is required. The solid glue used in this method does not require gel time and does not require a heating auxiliary device. Under the action of the hydraulic pressure and the internal and external pressure difference of the internal medium, the sealing structure can quickly take effect and plug the leak at the leaking part. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings described herein are for explanation purposes only and are not intended to limit the scope of the present invention in any way. In addition, the shapes and proportional dimensions of the components in the drawings are only for illustration purposes to help understand the present invention, and are not intended to specifically limit the shapes and proportional dimensions of the components of the present invention. In the drawings:

[0029] Figure 1 This is a schematic diagram of the well control pipeline with injection agent plugging system;

[0030] Figure 2 It is the front view of the semi-circular fixture;

[0031] Figure 3 It is a side view of the semi-circular fixture;

[0032] Figure 4 A flow chart of the method for plugging leaks with pressure injection agent for well control pipelines;

[0033] Among them, 1-well control pipeline, 2-leakage plugging fixture, 3-injection nozzle, 4-injection valve, 5-injection pressure display gauge, 6-injection gun, 7-sealant, 8-high-pressure oil pipe, 9-hydraulic oil pump, 10-system pressure display gauge, 20-pipeline installation hole, 21-semi-annular fixture, 22-diversion valve, 23-fastening bolts, 24-radial rubber pad, 25-axial rubber pad, 26-end face flange. DETAILED DESCRIPTION

[0034] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0035] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only embodiment.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0037] The present invention is described in detail below with reference to the accompanying drawings.

[0038] like Figure 1 As shown, an online plugging device for a well control pipeline of the present invention comprises: a plugging fixture 2, an injection device and a hydraulic oil pump 9.

[0039] The plugging fixture 2 is arranged at the leak on the well control pipeline 1, and the two ends of the plugging fixture 2 are respectively connected to the well control pipeline 1. The plugging fixture 2 can achieve initial sealing and plugging. The plugging fixture includes two interconnected parts. Specifically, the part is a semi-annular fixture 21. The two semi-annular fixtures 21 are assembled into a hollow cylinder.

[0040] The two semi-annular clamps 21 are provided with pipeline installation holes 20 in the axial direction, and the two semi-annular clamps 21 are provided with drainage holes and injection holes in the radial direction, and the drainage holes and injection holes are both connected with the pipeline installation holes 20. A groove is provided inside the pipeline installation hole 20 of the semi-annular clamp 21, and the groove is connected with the injection hole. A drainage valve 22 is provided outside the drainage hole, and the drainage valve 22 is a one-way valve, which can ensure the sealing performance and can ensure that the leakage direction of the medium is controllable when the personnel installs it, thereby reducing the installation resistance and improving the safety of the personnel during operation. Optionally, the number of the drainage hole and the injection hole is one, and the injection hole and the drainage hole are respectively provided on the two assembled parts.

[0041] The injection hole is connected to the injection device; the other end of the injection device is connected to the hydraulic oil pump 9. The injection device includes an injection nozzle 3, an injection valve 4, an injection gun 6 and a high-pressure oil pipe 8 connected in sequence, and the injection gun 6 can be filled with a sealant 7.

[0042] The injection nozzle 3 is connected to the injection hole, and the high-pressure oil pipe 8 is connected to the hydraulic oil pump 9. An injection pressure display gauge 5 is provided on the pipeline between the injection valve 4 and the injection gun 6.

[0043] The injection gun 6 is filled with sealant 7; after the hydraulic oil pump 9 is turned on, the injection device pushes the sealant 7 into the sealing interlayer in the plugging fixture 2. The sealant 7 is made of a polymer composite pressure-resistant medium material, which is in a solid form and can be reshaped by high pressure. The ingredients include tackifiers, fillers, polyester plasticizers, polytetrafluoroethylene resins, coarse aggregate materials, etc. It has the characteristics of high pressure resistance, corrosion resistance, good air tightness, and long storage time. It is suitable for media with large pressure difference fluctuations.

[0044] Put the solid sealant 7 into the injection gun 6, turn on the hydraulic oil pump 9, and the pressure in the high-pressure oil pipe 8 pushes the sealant 7 into the fixture cavity. The sealant 7 is reshaped into the shape of the cavity of the semi-annular fixture 21 by pressure to achieve high-pressure sealing of the fixture.

[0045] like Figure 2 As shown, the plugging fixture 2 includes two semi-annular fixtures 21, and the semi-annular fixtures 21 are semicircular ring structures. Specifically, the two semi-annular fixtures 21 are of the same size. Both ends of the semi-annular fixtures 21 are provided with connecting plates with through holes, and the two semi-annular fixtures 21 are connected by fastening bolts 23, and the fastening bolts 23 pass through the through holes of the connecting plates to connect the two semi-annular fixtures 21.

[0046] like Figure 3 As shown, the semi-annular clamp 21 is provided with a pipeline installation hole 20 as a sealed cavity. In the pipeline installation hole 20 , a radial rubber pad 24 is provided along the radial direction of the semi-annular clamp 21 , and an axial rubber pad 25 is provided along the axial direction of the semi-annular clamp 21 .

[0047] The operation process of the online plugging device for well control pipeline of the present invention is as follows:

[0048] After the well control pipeline 1 is found to be leaking, the downstream throttle valve of the well control system is opened to relieve the system pressure. Then, a plugging fixture 2 is installed at the leaking position of the well control pipeline 1. The plugging fixture 2 is provided with a drainage hole, and the drainage valve 22 is opened to ensure that the medium can only flow out from the drainage hole during subsequent operations.

[0049] After the plugging fixture 2 is installed, the connecting bolts are tightened to ensure the deformation of the multi-layer sealing structure inside the fixture, so as to achieve preliminary plugging of low-pressure online working conditions under pressure relief.

[0050] Then install the injection nozzle 3, injection valve 4, injection gun 6 at the injection hole reserved on the plugging fixture 2, connect the high-pressure oil pipe 8 and the hydraulic oil pump 9, and put the solid sealant 7 into the injection gun 6. Remotely start the hydraulic oil pump 9 to push the solid sealant 7 into the sealing cavity of the plugging fixture 2. Then close the drainage valve 22. At this time, the fixture, injection valve 4, injection gun 6 and oil pipe form a closed space. Control the pressure of the hydraulic oil to stimulate the high pressure-bearing sealing performance of the solid sealant 7.

[0051] At this time, the well control pipeline 1 has achieved high-pressure plugging and sealing, the downstream throttle valve can be closed or opened according to operational requirements, and the well control system pipeline can normally implement other operations such as well killing. At the same time, during the use of the well control manifold, the injection pressure can be remotely adjusted according to the medium pressure in the pipeline to maintain the internal and external pressure difference, ensuring that the clamp can still achieve sealing effect and pressure bearing capacity under higher system pressure.

[0052] Example

[0053] This embodiment provides a plugging method capable of achieving online working conditions of a well control pipeline with a pressure of 84 MPa, and the specific failure form is considered to be puncture leakage of the blowout preventer pipeline body.

[0054] like Figures 1 to 4 As shown, the plugging fixture 2 is installed at different leakage positions on the well control pipeline 1. The plugging fixture 2 can be used for various pipe fittings and valves of different forms on the well control pipeline 1. The fixture principles for different pipe fittings and valves are the same, and the structural forms are similar. The structure is slightly adjusted according to the form of the pipe fittings and valves. A drainage hole and an injection hole are respectively arranged on the two assembled parts of the plugging fixture 2, and the injection hole and the drainage hole are arranged oppositely. An injection nozzle 3 is installed on the injection hole, and the injection nozzle 3 is connected to the injection valve 4, and the injection valve 4 is connected to the injection gun 6. An injection pressure display meter 5 is installed between the injection valve 4 and the injection gun 6 to display the injection pressure. The injection gun 6 is filled with solid sealant 7, and the outside is connected to a high-pressure oil pipe 8, and the high-pressure oil pipe 8 is connected to a hydraulic oil pump 9. The system pressure display meter is installed on the well control pipeline 1 to display the medium pressure in the pipeline. The length of the high-pressure oil pipe 8 must ensure that a person has a certain safe distance from the leak point of the well control pipeline 1 when operating the pressure pump. The hydraulic oil pump 9 can be a manual pressure pump or an electric pressure pump according to the system pressure and the size of the leak point.

[0055] The specific steps are as follows:

[0056] S1) After confirming the pipeline leakage point, the pipeline is depressurized or the upstream valve is closed.

[0057] Under normal operating conditions, the system pressure will not be too high. However, under extreme conditions, when the system pressure exceeds 5MPa, it is necessary to first open the downstream relief valve to release the pressure or close the upstream valve and then take plugging measures to avoid excessive risk factors in on-site operations.

[0058] S2) According to the leak point position and pressure of the well control pipeline 1, all components of the well control pipeline online leak plugging device of the present invention are prepared.

[0059] The leak-proof fixture 2 comprises two semi-annular fixtures 21, four fastening bolts 23, two radial rubber pads 24, four axial rubber pads 25, and four end face flanges 26. A groove cavity is arranged inside the semi-annular fixture 21 as an injection space.

[0060] S3) Install the leak-proof fixture 2 and pre-tighten the bolts.

[0061] Before installing the plugging fixture 2, the drainage valve 22 must be opened to ensure that the medium can flow out through the drainage port when the fixture is installed, reducing installation resistance and personnel safety risks. When installing the straight pipe fixture, first connect the two-open clamp near the leak point, then quickly move the clamp horizontally to the leak point after connection, and then tighten the bolts to achieve preliminary plugging of low-pressure online working conditions.

[0062] S4) Connect pipelines, valves, injection devices, pumps and other facilities.

[0063] After installing the leak plugging fixture 2, connect the injection nozzle 3, the injection valve 4, the injection pressure display meter 5, the injection gun 6, the high-pressure oil pipe 8, and the hydraulic oil pump 9 in sequence.

[0064] The two ends of the high-pressure oil pipe 8 are connected by quick interfaces, and the length is greater than 10 meters. There is a wall between the hydraulic oil pump 9 and the leakage point of the blowout prevention pipeline at the test site to ensure operational safety.

[0065] S5) Confirm that the installation is correct, turn on the hydraulic pump, and inject the solid sealing injection into the fixture cavity.

[0066] Fill the solid sealant 7 into the injection gun 6, turn on the hydraulic oil pump 9, use the hydraulic oil pressure to push the sealant 7 into the fixture cavity, then close the drainage valve 22, use high pressure to re-plasticize the solid glue stick in the fixture cavity, and stimulate the sealing pressure-bearing capacity of the solid sealant through the pressure of the hydraulic oil.

[0067] S6) Observe the system pressure. If the system pressure rises, a second injection should be carried out to replenish and compact it to prevent stress relaxation until the leakage disappears.

[0068] Increase the system pressure, observe the leakage point, adjust the pressure of the injection gun 6 according to the system pressure, and perform additional injection and compaction to prevent stress relaxation until the leakage disappears.

[0069] The above description is only an illustrative embodiment of the present invention and is not intended to limit the scope of the present invention. Any equivalent changes and modifications made by any person skilled in the art without departing from the concept and principle of the present invention shall fall within the protection scope of the present invention.

[0070] Unless otherwise specified, the device elements involved in the above embodiments are all conventional device elements, and the structural settings, working modes or control modes involved are all conventional settings, working modes or control modes in the art unless otherwise specified.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in the field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. An online leak plugging device for well control pipeline, characterized in that: include: A leak-stopping clamp (2), the leak-stopping clamp (2) comprising two mutually connected parts; An injection device, one end of which is connected to the leak-stopping fixture (2), and the other end of which is connected to a pump; The two assembled parts are assembled into a hollow cylinder, and the two assembled parts are provided with a pipeline installation hole (20) along the axial direction, and the pipeline installation hole (20) matches the outer wall of the well control pipeline (1); the two assembled parts are provided with a drainage hole and an injection hole along the radial direction, and the drainage hole and the injection hole are both connected to the pipeline installation hole (20); a drainage valve (22) is arranged outside the drainage hole, and the drainage valve (22) is a one-way valve, and the injection hole is connected to the injection device; the injection device includes an injection gun (6), and the injection gun (6) can be filled with a sealant (7).

2. The online leak plugging device for well control pipeline according to claim 1 is characterized in that: A groove is provided in the pipeline installation hole (20) of the assembled piece, and the groove is communicated with the injection hole.

3. The online leak plugging device for well control pipeline according to claim 1, characterized in that: The injection device comprises an injection nozzle (3), one end of the injection nozzle (3) is connected to the injection hole, and the other end is connected to the injection gun (6).

4. The online leak plugging device for well control pipeline according to claim 3 is characterized in that: An injection valve (4) is provided between the injection nozzle (3) and the injection gun (6).

5. The well control pipeline online leak plugging device according to claim 4 is characterized in that: An injection pressure display gauge (5) is provided on the pipeline between the injection valve (4) and the injection gun (6).

6. The online leak plugging device for well control pipeline according to claim 1, characterized in that: The pump is a hydraulic oil pump (9), and the hydraulic oil pump (9) is connected to the injection gun (6) via a high-pressure oil pipe (8).

7. The online leak plugging device for well control pipeline according to claim 1, characterized in that: In the pipeline installation hole (20), a radial rubber pad (24) is arranged along the radial direction of the assembly part, and an axial rubber pad (25) is arranged along the axial direction of the assembly part.

8. The well control pipeline online leak plugging device according to claim 1, characterized in that: The number of the drainage hole and the number of the injection hole are both one, and the injection hole and the drainage hole are respectively opened on the two assembled parts.

9. The online leak plugging device for well control pipeline according to claim 1, characterized in that: The sealant (7) is made of a polymer composite pressure-resistant variable dielectric material.

10. A method for using an online leak plugging device for well control pipelines according to any one of claims 1 to 9, characterized in that: The following steps are involved: Open the drainage valve (22), and install a plugging fixture (2) and an injection device at the leaking position of the well control pipeline (1); Putting a solid sealant (7) into an injection gun (6); The drainage valve (22) is closed, and the pump is remotely started to push the solid sealant (7) into the leak-proof fixture (2) through hydraulic oil; The pressure of the hydraulic oil is controlled to stimulate the high pressure-bearing sealing performance of the solid sealant (7).

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