Dual-liquid-supply self-pressurizing packer and hydraulic fracturing equipment

Abstract

The utility model belongs to the technical field of hydraulic fracturing equipment, and specifically discloses a self-pressurizing packer with double-path liquid supply and hydraulic fracturing equipment. The utility model creatively introduces a differential pressure assembly composed of a first pressurizing piston and a second pressurizing piston with different areas. By means of the small differential pressure between the first channel and the second channel, the piston area difference is amplified to a greater thrust acting on the packer capsule. This makes the final inflation sealing pressure of the packer mainly come from the self-pressurizing effect inside the equipment, instead of completely relying on the external high-pressure pump to continuously provide extremely high pressure. The self-pressurizing packer with double-path liquid supply and the hydraulic fracturing equipment provided by the utility model effectively realize the rapid, synchronous and stable inflation and reliable sealing of the packer under a lower external input pressure through the unique double-path liquid supply and self-pressurizing structural design, reduce the dependence on high-pressure pumping, and improve the overall efficiency, safety and economy of the hydraulic fracturing operation.

Description

Technical Field

[0001] This utility model belongs to the technical field of hydraulic fracturing equipment, and relates to a self-pressurizing packer with dual-supply and hydraulic fracturing equipment. Background Technology

[0002] Hydraulic fracturing technology is widely used in geological exploration, oil and gas extraction, and geotechnical engineering. The performance of its core component, the packer, directly determines the effectiveness and safety of fracturing operations. Currently, traditional hydraulic fracturing equipment mainly relies on a single fluid / water supply channel to pressurize and expand the packer, achieving sealing and isolation of the target section of the borehole (the fracturing section). However, this structure reveals significant drawbacks in practical applications: under a single fluid / water supply method, the expansion processes of the front and rear packers are difficult to synchronize. Delayed or uneven pressure transmission can easily lead to poor sealing between the packer and the borehole wall, creating sealing failure points and causing fracturing fluid leakage, severely affecting the effective establishment and maintenance of fracturing pressure.

[0003] To address the aforementioned issues, while existing technologies have developed hydraulic fracturing devices employing dual-supply / water systems, the pressurization drive method for packers still largely relies on an external high-pressure pump to directly provide a continuous high-pressure fluid flow. This method not only consumes a lot of energy but also places extremely stringent requirements on the stability of the pumping pressure. Under complex and variable formation conditions, even small fluctuations in the external pump pressure can easily lead to unstable packer expansion, thereby weakening the reliability of the seal.

[0004] Therefore, there is an urgent need to develop a new type of packer and hydraulic fracturing equipment that can achieve rapid, stable and synchronous expansion and sealing of the packer under lower external input pressure, thereby effectively improving the reliability, adaptability and economic benefits of hydraulic fracturing operations. Utility Model Content

[0005] The purpose of this invention is to propose a self-pressurizing packer with dual-supply system and a hydraulic fracturing device, which enables the packer to expand and seal rapidly, stably, and synchronously under relatively low external input pressure.

[0006] To achieve the above objectives, this utility model adopts the following technical solution: A self-pressurizing packer with dual-supply system includes: The fitting has an internal hollow cavity with a first channel connected to it, and an overflow hole connected to the hollow cavity is opened in the middle of the fitting. The first pipeline connects to the hollow cavity; The anterior bladder is located at the front end of the tube fitting; The rear bladder is located at the rear end of the tube. The second tube connects the anterior and posterior capsules via the second channel; The differential pressure assembly includes a first sliding cavity and a second sliding cavity that are connected. A first booster piston is slidably fitted in the first sliding cavity, and a second booster piston is slidably fitted in the second sliding cavity. The first booster piston is connected to the second booster piston via a transition piece. The outer end face area of ​​the first booster piston is larger than that of the second booster piston. The first channel is connected to the outer end of the first sliding cavity, and the second channel is connected to the outer end of the second sliding cavity.

[0007] Preferably, a return spring is connected between the outer end face of the second booster piston and the outer end of the second sliding cavity.

[0008] Preferably, the differential pressure assembly includes a support body located between the tube and the front and / or rear bladder bodies, and a first sliding cavity and a second sliding cavity are formed within the support body.

[0009] Preferably, the front end of the pipe fitting is provided with an interface communicating with the hollow cavity, and the first pipe is connected to the interface.

[0010] Preferably, the pipe fitting includes two sleeve pipe fittings and one flower pipe fitting. The overflow port is an opening on the flower pipe fitting. One end of the flower pipe fitting is connected to one sleeve pipe fitting. A front bladder is provided on one sleeve pipe fitting, and a rear bladder is provided on the other sleeve pipe fitting. At least one sleeve pipe fitting has a pipeline that communicates with the hollow cavity and the first channel respectively.

[0011] Preferably, the perforated pipe fitting and the sleeve fitting are connected by a pipe joint.

[0012] Preferably, the first pipeline is connected to a first pressure pump, which is used to supply fracturing fluid at a set pressure to the first pipeline; the second pipeline is connected to a second pressure pump, which is used to supply fracturing fluid at a set pressure to the second pipeline.

[0013] Preferably, a first pressure gauge and / or a first pressure sensor are connected to the first pipeline; and a second pressure gauge and / or a second pressure sensor are connected to the second pipeline.

[0014] Preferably, a shut-off valve is connected to the second pipeline.

[0015] A hydraulic fracturing device, wherein the hydraulic fracturing device is equipped with the aforementioned dual-supply self-pressurizing packer.

[0016] Compared with the prior art, this utility model has the following advantages: As described above, the dual-supply self-pressurizing packer and hydraulic fracturing device provided by this utility model achieve the following technical effects through its unique dual-supply and self-pressurizing structural design: 1. This invention achieves rapid, stable, and synchronous expansion and sealing of the packer. By setting up an independently connected second pipeline and second channel, fracturing fluid can be supplied to both the front and rear packers simultaneously, effectively avoiding the pressure transmission lag and uneven distribution problems of single-supply methods, thus ensuring that the expansion processes of the front and rear packers are basically synchronized. Combined with the self-pressurization effect of the differential pressure component, the packer packer can be driven to achieve secondary rapid expansion at a relatively low initial external fluid supply pressure, making it tightly and stably fitted to the borehole inner wall, significantly improving the reliability and establishment speed of the seal.

[0017] 2. This invention reduces reliance on external high-pressure pumps and energy consumption by creatively introducing a differential pressure assembly consisting of a first and a second pressurizing piston with unequal areas. Utilizing the small pressure difference between the first and second channels, the piston area difference amplifies this difference into a larger thrust acting on the packer bladder. This ensures that the packer's final expansion sealing pressure primarily originates from the internal self-pressurization effect, rather than entirely relying on a continuously supplying extremely high pressure from an external high-pressure pump. Therefore, it significantly reduces the requirements and stability dependence on the output pressure of the first and second pressure pumps, decreases equipment energy consumption, and improves the system's adaptability and economy under complex geological conditions.

[0018] 3. This invention improves the reliability and sealing maintenance capability of fracturing operations. After the packer undergoes initial expansion, the secondary pressurization achieved through the differential pressure assembly enables the packer to obtain a continuous and stable high contact pressure. This allows for more effective resistance to the impact and pressure fluctuations of fracturing fluid when establishing high pressure in the fracturing section, preventing seal failure and fracturing fluid leakage. This ensures that the high-pressure environment within the fracturing section can be effectively established and maintained, directly improving the success rate and effectiveness of hydraulic fracturing operations.

[0019] In summary, this invention effectively achieves rapid, synchronous, stable expansion and reliable sealing of the packer under relatively low external input pressure, reduces reliance on high-pressure pumping, and improves the overall efficiency, safety, and economy of hydraulic fracturing operations. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0021] Figure 1 This is a schematic diagram of the structure of the self-pressurizing packer with dual-channel liquid supply according to an embodiment of the present invention; Figure 2 This is a radial sectional view of the tubular fittings, bladder, and other components in an embodiment of this utility model; Figure 3 This is an axial sectional view of the pipe fittings, bladder, and other components in an embodiment of this utility model; Figure 4 This is a cross-sectional view of the differential pressure assembly according to an embodiment of the present invention; Figure 5 This is a structural schematic diagram of the differential pressure component in an embodiment of the present invention. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0023] Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0024] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0025] Furthermore, in this utility model, the use of terms such as "first," "second," etc., is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0026] In this utility model, unless otherwise explicitly specified and limited, the terms "connection," "fixing," etc., should be interpreted broadly. For example, "fixing" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0027] Furthermore, the technical solutions of the various embodiments of this utility model can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0028] like Figures 1 to 5As shown, the dual-supply self-pressurizing packer of this embodiment includes a pipe 1, a first pipe 21, a front bladder 31, a rear bladder 32, a second pipe 22, and a differential pressure assembly.

[0029] The interior of the pipe fitting 1 is configured as a hollow cavity 10, which is connected to a first channel 11. An overflow hole 12 is opened in the middle of the pipe fitting 1, and the overflow hole 12 is connected to the hollow cavity 10.

[0030] The first pipe 21 is connected to the hollow cavity 10. Specifically, the front end of the pipe fitting 1 is provided with an interface, and the rear end of the pipe fitting 1 is provided with a plug. The interface is connected to the hollow cavity 10, and the first pipe 21 is connected to the interface.

[0031] The front end of the fitting 1 is provided with a front bladder 31, and the rear end of the fitting 1 is provided with a rear bladder 32. The overflow hole 12 is located between the front bladder 31 and the rear bladder 32. The front bladder 31 and the rear bladder 32 surround and wrap around the fitting 1.

[0032] The second conduit 22 connects the anterior bladder 31 and the posterior bladder 32 via the second channel 23. The second conduit 22 between the anterior bladder 31 and the posterior bladder 32 is connected by a connecting pipe 221.

[0033] The differential pressure assembly includes a support body 41. The support body 41 is disposed between the tube 1 and the front bladder 31, and between the tube 1 and the rear bladder. A first sliding cavity 411 and a second sliding cavity 412 are formed inside the support body 41, and the first sliding cavity 411 and the second sliding cavity 412 are connected.

[0034] The differential pressure component is integrated into the support body 41 and rationally arranged with the pipes and bladder, making the entire packer structure compact and easy to install and arrange in the borehole 7.

[0035] A first booster piston 42 is slidably fitted in the first sliding cavity 411, and a second booster piston 43 is slidably fitted in the second sliding cavity 412. The first booster piston 42 is connected to the second booster piston 43 via a transition piece 44 (pin). The outer end face area of ​​the first booster piston 42 is larger than the outer end face area of ​​the second booster piston 43.

[0036] The first channel 11 is connected to the outer end of the first sliding cavity 411, and the second channel 23 is connected to the outer end of the second sliding cavity 412.

[0037] A return spring 45 is connected between the outer end face of the second booster piston 43 and the outer end of the second sliding cavity 412. During the use of the packer, the pressure difference drives the first booster piston 42 and the second booster piston 43 to move in the forward direction to compress the return spring 45. When the packer is not in use, the first booster piston 42 and the second booster piston 43 move in the reverse direction under the elastic force of the return spring 45 to reset.

[0038] The fitting 1 includes two sleeve fittings and one perforated fitting. The sleeve fitting is configured as a drill pipe, and the overflow port 12 is an opening on the perforated fitting. The two ends of the perforated fitting are connected to the sleeve fitting via pipe joints 13. A front bladder 31 is provided on one sleeve fitting, and a rear bladder 32 is provided on the other sleeve fitting. Each sleeve fitting has a pipe 14 that communicates with the hollow cavity 10 and the first channel 11 respectively.

[0039] The first pipeline 21 is connected to a first pressure pump 51, which supplies fracturing fluid at a set pressure to the first pipeline 21. The second pipeline 22 is connected to a second pressure pump 52, which supplies fracturing fluid at a set pressure to the second pipeline 22.

[0040] The first pipeline 21 is connected to a first pressure gauge 61 and a first pressure sensor 62; the second pipeline 22 is connected to a second pressure gauge 63, a second pressure sensor, and a shut-off valve 64. The shut-off valve 64 can be configured as a solenoid valve to enable automatic and remote control of the shut-off valve 64.

[0041] By installing pressure gauges, pressure sensors, and shut-off valves 64 on the first pipeline 21 and the second pipeline 22 respectively, operators can monitor and control the fracturing fluid pressure leading to the fracturing section and packer in real time and independently. This not only allows operators to accurately adjust the packer's expansion state and sealing tightness according to actual conditions, but also enables timely intervention in case of abnormal pressure, ensuring the safety and controllability of the entire fracturing operation.

[0042] A hydraulic fracturing device is provided, wherein the hydraulic fracturing device is equipped with the self-pressurizing packer with dual-supply as described in this embodiment.

[0043] The dual-supply self-pressurizing packer in this embodiment is used in a hydraulic fracturing device, and its operation process is as follows: 1. Sealing preparation stage The pipe fitting 1, front bladder 31, rear bladder 32 and differential pressure assembly of the dual-supply self-pressurizing packer of this embodiment are placed in the borehole 7, and the section between the front bladder 31 and the rear bladder 32 is the fracturing section.

[0044] 2. Initial expansion and sealing stage The second pressure pump 52 is started, injecting fracturing fluid at a set pressure into the front and rear bladders 31 and 32 via the second pipeline 22 and the second channel 23. The front and rear bladders 31 and 32 undergo initial expansion, initially adhering to the inner wall of the borehole 7 to form a preliminary seal. During this process, the data from the second pressure gauge 63 is observed, or the fracturing fluid pressure in the second pipeline 22 is monitored using the second pressure sensor to ensure that the pressure of the fracturing fluid injected into the second pipeline 22 is within a reasonable range, avoiding excessively high or low pressure that could affect the initial expansion effect of the front and rear bladders 31 and 32. After the front and rear bladders 31 and 32 have initially expanded, the second pipeline 22 can be shut off and the second pressure pump 52 stopped via the shut-off valve 64. If the pressure of the fracturing fluid in the second pipeline 22 exceeds the reasonable range, the second pressure pump 52 is restarted, and the second pipeline 22 is reopened via the shut-off valve 64.

[0045] 3. Secondary pressurization expansion sealing and water pressure-induced cracking stage After the initial expansion of the front capsule 31 and the rear capsule 32, the first pressure pump 51 is activated. The pressure of the fracturing fluid injected into the first pipeline 21 is monitored by observing the data on the first pressure gauge 61 or by using the first pressure sensor 62 to ensure that the pressure of the fracturing fluid injected into the first pipeline 21 is within a reasonable range. The fracturing fluid in the first pipeline 21 enters the hollow cavity 10 and the first channel 11.

[0046] The fracturing fluid in the first channel 11 enters the first sliding chamber 411 and acts on the outer end face of the first booster piston 42, while the fracturing fluid in the second channel 23 enters the second sliding chamber 412 and acts on the outer end face of the second booster piston 43. Because the outer end face area of ​​the first booster piston 42 is larger than that of the second booster piston 43, when the fracturing fluid pressure in the first channel 11 is equal to or slightly less than the fracturing fluid pressure in the second channel 23, a pressure difference is generated between the fracturing fluid on both sides acting on the first booster piston 42 and the second booster piston 43. This pressure difference pushes the first booster piston 42 and the second booster piston 43 to move in the forward direction to compress the return spring 45, thereby causing the front bladder 31 and the rear bladder 32 to expand secondary.

[0047] During the secondary pressurization and expansion process, the fracturing hydraulic pressure in the first pipeline 21 is continuously increased. Based on the actual pressure changes and the expansion of the bladder, the output of the fracturing hydraulic pressure from the first pressure pump 51 is adjusted to precisely control the pressure difference, thereby achieving precise adjustment of the degree of secondary expansion of the bladder and ensuring that the bladder and the inner wall of the borehole 7 achieve the best fit and form a high-strength seal.

[0048] During and after the secondary pressurization and expansion, fracturing fluid is continuously injected into the pipe fitting 1 via the first pressure pump 51, and high-pressure fracturing fluid is injected into the fracturing section through the overflow orifice 12. At this time, due to the good sealing of the bladder, the fracturing fluid can effectively act on the target rock formation, causing the rock formation to gradually fracture and completing the hydraulic fracturing operation. Throughout the hydraulic fracturing process, the data of the pressure monitoring components (first pressure gauge 61, first pressure sensor 62, second pressure gauge 63, second pressure sensor) are continuously monitored to ensure that the fracturing fluid pressure is stable and within a safe range. If any abnormalities are found, the output parameters of the first pressure pump 51 and the second pressure pump 52 are adjusted in a timely manner to ensure the smooth progress of the operation and construction safety.

[0049] 4. Work completion and equipment maintenance After the hydraulic fracturing operation is completed, first shut down the first pressure pump 51 and the second pressure pump 52 to release the pressure in the pipeline. Then, disassemble all connecting parts, clean and inspect them, and replace or repair any damaged or deformed parts in a timely manner to prepare for the next operation.

[0050] The present embodiment has now been described in detail with reference to the accompanying drawings. Based on the above description, those skilled in the art should have a clear understanding of the dual-supply self-pressurizing packer and hydraulic fracturing device of this utility model. Of course, the above description is only a preferred embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural transformations made using the content of this utility model's specification and drawings under the inventive concept of this utility model, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this utility model and should be protected by this utility model.

Claims

1. A self-pressurizing packer with dual-supply system, characterized in that, include: The fitting has an internal hollow cavity with a first channel connected to it, and an overflow hole connected to the hollow cavity is opened in the middle of the fitting. The first pipeline connects to the hollow cavity; The anterior bladder is located at the front end of the tube fitting; The rear bladder is located at the rear end of the tube. The second tube connects the anterior and posterior capsules via the second channel; The differential pressure assembly includes a first sliding cavity and a second sliding cavity that are connected. A first booster piston is slidably fitted in the first sliding cavity, and a second booster piston is slidably fitted in the second sliding cavity. The first booster piston is connected to the second booster piston via a transition piece. The outer end face area of ​​the first booster piston is larger than that of the second booster piston. The first channel is connected to the outer end of the first sliding cavity, and the second channel is connected to the outer end of the second sliding cavity.

2. The self-pressurizing packer with dual-supply system according to claim 1, characterized in that, A return spring is connected between the outer end face of the second booster piston and the outer end of the second sliding cavity.

3. The self-pressurizing packer with dual-supply system according to claim 1, characterized in that, The differential pressure assembly includes a support body located between the tubing and the front and / or rear bladder bodies, with a first sliding cavity and a second sliding cavity formed within the support body.

4. The self-pressurizing packer with dual-supply system according to claim 1, characterized in that, The front end of the pipe fitting is provided with an interface that communicates with the hollow cavity, and the first pipe is connected to the interface.

5. The self-pressurizing packer with dual-supply system according to claim 1, characterized in that, The pipe fitting includes two sleeve fittings and one flower fitting. The overflow port is an opening on the flower fitting. One end of the flower fitting is connected to one sleeve fitting. A front bladder is provided on one sleeve fitting and a rear bladder is provided on the other sleeve fitting. At least one sleeve fitting has a pipe that is connected to the hollow cavity and the first channel respectively.

6. The self-pressurizing packer with dual-supply system according to claim 5, characterized in that, The pipe fittings and sleeve fittings are assembled and connected via pipe joints.

7. The dual-supply self-pressurizing packer according to any one of claims 1 to 6, characterized in that, The first pipeline is connected to a first pressure pump, which is used to supply fracturing fluid at a set pressure to the first pipeline; the second pipeline is connected to a second pressure pump, which is used to supply fracturing fluid at a set pressure to the second pipeline.

8. The self-pressurizing packer with dual-supply system according to claim 7, characterized in that, The first pipeline is connected to a first pressure gauge and / or a first pressure sensor; the second pipeline is connected to a second pressure gauge and / or a second pressure sensor.

9. The self-pressurizing packer with dual-supply system according to claim 7, characterized in that, A shut-off valve is connected to the second pipeline.

10. A hydraulic fracturing device, characterized in that, The hydraulic fracturing device is equipped with a self-pressurizing packer with dual-supply as described in any one of claims 1 to 9.

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