Improved structure of oil underground pitching sliding sleeve

Abstract

The invention discloses an improved structure of a petroleum underground pitching sliding sleeve, and relates to the technical field of pitching sliding bushs.The improved structure comprises a pipeline, connectors are fixedly connected to the two ends of the pipeline, a plurality of clamping assemblies are arranged on the outer wall of the pipeline, a sliding sleeve is installed in the pipeline, a pitching ball is arranged in the sliding sleeve, and the clamping assemblies comprise pins; one end of the pin penetrates to the inner wall of the pipeline and is sleeved with a positioning block in a threaded mode. An elastic unlocking mechanism is composed of the button, the round pipe and the spring, under the normal working condition, the elastic force of the spring pushes the round pipe to abut against the interior of the pin, threaded connection and locking of the pin and the positioning block are guaranteed, thread loosening is prevented, when the sliding sleeve needs to be detached for overhaul, the button is pressed to compress the spring and drive the round pipe to retract, the locking state of the pin can be quickly relieved, and the service life of the pin is prolonged. The dowel can be drawn out by screwing out the positioning block, and cutting-free quick disassembly of the sliding sleeve is achieved.

Description

Technical Field

[0001] This invention relates to the field of ball-feeding sliding sleeve technology, specifically an improved structure of a ball-feeding sliding sleeve for oil wells. Background Technology

[0002] The ball-drop sliding sleeve is a core downhole tool for segmented fracturing of oil and gas wells. It is mainly used for stratified fracturing operations in horizontal wells and highly deviated wells. Its core function is to achieve precise opening of reservoir segments and control of fracturing channels by dropping balls and pressurizing, ultimately improving the utilization efficiency of heterogeneous reservoirs and the production capacity of oil and gas wells.

[0003] The existing improved structure of the ball-feeding sliding sleeve in oil wells depends on whether the pin can be neatly destroyed when the sleeve moves down. However, the pin cannot be reused after it is crushed, which easily leads to resource waste. Therefore, an improved structure of the ball-feeding sliding sleeve in oil wells is proposed. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art and solve at least one of the technical problems mentioned in the background art, the present invention proposes an improved structure for a ball-dropping sliding sleeve in oil wells.

[0005] The technical solution adopted by the present invention to solve its technical problem is: an improved structure of a ball-throwing sliding sleeve in an oil well, including a pipe, both ends of which are fixedly connected to connectors, the outer wall of the pipe is provided with multiple sets of locking components, a sliding sleeve is installed inside the pipe, and a ball is disposed inside the sliding sleeve;

[0006] The multiple sets of the engagement components include a pin, one end of which penetrates into the inner wall of the pipe, a positioning block is threaded onto one end of the pin, a locking block is hinged to the other end of the pin, a button is provided at one end of the pin, a round tube is fixedly connected to one end of the button, the round tube moves inside the pin, and a spring is connected to one end of the round tube.

[0007] The outer side of the pipe is provided with external threads, and a secondary locking assembly is connected to the outer side of the pipe through the external threads. The secondary locking assembly is used to prevent the positioning block from falling off.

[0008] Preferably, the secondary locking assembly includes a rotating collar with multiple threaded holes, each of which is threaded with a locking bolt.

[0009] Preferably, each of the positioning blocks has a fixing hole adapted to the threaded hole, and the number of the threaded holes is the same as the number of fixing holes.

[0010] Preferably, the outer wall of the pipe has a plurality of first circular holes, and one end of the pin passes through the interior of the first circular holes.

[0011] Preferably, a keyway is formed on the surface of the other end of the pin, and the positioning block is installed inside the keyway.

[0012] Preferably, one end of the spring is fixedly connected to a four-corner plate, which is fixedly connected to the inner wall of the pin.

[0013] Preferably, a vertical plate is fixedly connected to the outer wall of the sliding sleeve, and a vertical groove is opened inside the pipe, with the vertical plate engaging inside the vertical groove.

[0014] Preferably, the surface of the vertical plate is provided with a second circular hole, and the first circular hole and the second circular hole are symmetrical to each other.

[0015] Preferably, the inner walls of both the first and second circular holes are provided with rubber rings.

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] 1. This invention uses a connector as the connecting component between the pipeline and the downhole tubing string, ensuring a rigid connection and sealing performance between the sliding sleeve and the tubing string, preventing fracturing fluid leakage from the connection point. Simultaneously, the standardized connector structure can adapt to different specifications of downhole tubing strings, improving the versatility of the sliding sleeve. A pin penetrates the outer wall of the pipeline and extends into the inner wall, engaging with a pre-set positioning groove on the outer wall of the sliding sleeve. A positioning block is connected to the end of the pin via a thread, allowing for fine-tuning of the pin's insertion depth and precise locking of the sliding sleeve's axial position within the pipeline. This prevents displacement of the sliding sleeve due to downhole fluid impact or tubing string vibration, ensuring coaxiality during ball-setting. The locking block is hinged to... The exposed end of the pin has a locking block that can rotate around the hinge point. After the sliding sleeve is installed in place, rotating the locking block causes it to engage with the groove or limiting platform on the inner wall of the tube, further enhancing the overall impact resistance and stability of the sliding sleeve and preventing it from shifting under high pressure during cracking. The button, round tube, and spring form an elastic unlocking mechanism. Under normal working conditions, the spring force pushes the round tube to press against the inside of the pin, ensuring that the threaded connection between the pin and the positioning block is locked and preventing the threads from loosening. When the sliding sleeve needs to be disassembled for maintenance, pressing the button compresses the spring, causing the round tube to retract, which can quickly release the locking state of the pin. The pin can then be pulled out by unscrewing the positioning block, achieving quick disassembly of the sliding sleeve without cutting.

[0018] 2. After the positioning block is tightened, rotate the rotating collar to move it downwards, aligning each threaded hole on the rotating collar with the fixing hole on each positioning block. Then, screw the locking bolt into the threaded hole. Since the threaded hole corresponds to the fixing hole, the locking bolt enters the fixing hole to fix the positioning block, thereby preventing the positioning block on the pin from falling off and achieving secondary locking of the positioning block. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a perspective view of the invention from a first viewpoint.

[0021] Figure 2 This is a schematic diagram of the structural separation of the present invention;

[0022] Figure 3 This is a cross-sectional structural diagram of the present invention;

[0023] Figure 4 This is a schematic diagram of the installation of the snap-fit ​​assembly structure of the present invention;

[0024] Figure 5 This is a schematic cross-sectional view of the engagement assembly of the present invention;

[0025] Figure 6 This is a schematic diagram of the secondary locking component structure installation of the present invention;

[0026] Figure 7 This is a schematic cross-sectional view of the secondary locking component of the present invention.

[0027] In the diagram: 1. Pipe; 2. Connector; 3. Engaging assembly; 301. Pin; 302. Locking block; 303. Positioning block; 304. Spring; 305. Round tube; 306. Button; 4. Sliding sleeve; 5. Vertical plate; 6. Second round hole; 7. Ball throwing; 8. Vertical groove; 9. First round hole; 10. Secondary locking assembly; 101. Rotating collar; 102. Locking bolt. Detailed Implementation

[0028] 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.

[0029] The embodiments of the present invention will now be described.

[0030] Please see Figures 1-5An improved structure of a ball-throwing sliding sleeve for oil wells includes a pipe 1, with connectors 2 fixedly connected to both ends of the pipe 1, multiple sets of locking components 3 provided on the outer wall of the pipe 1, a sliding sleeve 4 installed inside the pipe 1, and a ball 7 installed inside the sliding sleeve 4.

[0031] The multi-set locking assembly 3 includes a pin 301, one end of which penetrates the inner wall of the pipe 1. A positioning block 303 is threaded onto one end of the pin 301, and a locking block 302 is hinged to the other end of the pin 301. A button 306 is provided at one end of the pin 301, and a round tube 305 is fixedly connected to one end of the button 306. The round tube 305 moves inside the pin 301, and a spring 304 is connected to one end of the round tube 305.

[0032] The connector 2 serves as the connection between the pipe 1 and the downhole tubing, ensuring a rigid connection and sealing performance between the sliding sleeve 4 and the tubing, preventing fracturing fluid leakage from the connection point. The standardized connector structure also adapts to different specifications of downhole tubing, enhancing the versatility of the sliding sleeve 4. The pin 301 penetrates the outer wall of the pipe 1 and extends into the inner wall, engaging with a pre-set positioning groove on the outer wall of the sliding sleeve 4. The positioning block 303 is threaded to the end of the pin 301, allowing for fine-tuning of the pin 301's insertion depth. Precisely lock the axial position of the sliding sleeve 4 within the pipeline 1 to prevent displacement of the sliding sleeve 4 due to downhole fluid impact and tubing vibration, ensuring coaxiality during ball setting. The locking block 302 is hinged to the exposed end of the pin 301 and can rotate around the hinge point. After the sliding sleeve 4 is installed in place, rotate the locking block 302 to engage it in the groove or limiting platform on the inner wall of the tubing, further enhancing the overall impact resistance stability of the sliding sleeve 4 and preventing it from shifting under high pressure during fracturing. Button 306, round tube 305, and... Spring 304 forms an elastic unlocking mechanism. Under normal operating conditions, the elastic force of spring 304 pushes the round tube 305 to press against the inside of pin 301, ensuring that the threaded connection between pin 301 and positioning block 303 is locked and preventing loosening of the threads. When it is necessary to disassemble the sliding sleeve 4 for maintenance, pressing button 306 compresses spring 304, causing the round tube 305 to retract, which can quickly release the locking state of pin 301. By unscrewing positioning block 303, pin 301 can be pulled out, realizing quick disassembly of sliding sleeve 4 without cutting. Significantly reducing later maintenance costs, the sliding sleeve 4, as the core component for bearing and guiding the flow of the ball 7, provides a setting space for the ball 7 within its internal chamber. When the ball 7 descends with the fracturing fluid and sets inside the sliding sleeve 4, the pressure buildup on the ground can push the sliding core inside the sliding sleeve 4 to move, opening the fracturing fluid flow channel and realizing the fracturing transformation of the target reservoir. The ball 7 achieves sealing and pressure buildup through precise fit with the ball seat inside the sliding sleeve 4. Balls 7 of different sizes can be matched with sliding sleeves 4 of different sections to meet the needs of staged fracturing.

[0033] Please see Figure 3 and Figure 4The outer wall of the pipe 1 has several first circular holes 9. One end of the pin 301 passes through the inside of the first circular hole 9. The other end of the pin 301 has a keyway. The positioning block 303 is installed inside the keyway. One end of the spring 304 is fixedly connected to a four-corner plate, which is fixedly connected to the inner wall of the pin 301. The outer wall of the sliding sleeve 4 is fixedly connected to a vertical plate 5. The inside of the pipe 1 has a vertical groove 8. The vertical plate 5 is engaged inside the vertical groove 8. The surface of the vertical plate 5 has a second circular hole 6. The first circular hole 9 and the second circular hole 6 are symmetrical to each other. The inner walls of the first circular hole 9 and the second circular hole 6 are both provided with rubber rings.

[0034] The first circular hole 9 provides an installation channel for the pin 301 to penetrate the pipe 1. The second circular hole 6 is symmetrically designed with the first circular hole 9 and is the positioning hole for the pin 301 to be inserted into the vertical plate 5 after it extends into the pipe 1. The two are coaxially engaged to achieve double-layer fixed positioning of the pin 301 on the sliding sleeve 4 through the pipe 1 and the vertical plate 5, preventing the sliding sleeve 4 from axial movement or circumferential rotation under high pressure and vibration conditions underground. The keyway at the other end of the pin 301 provides a precise installation position for the positioning block 303, replacing the original threaded connection method, and achieving circumferential limiting of the positioning block 303 and the pin 301. This prevents the pin 301 from rotating and loosening during underground vibration, ensuring the stable locking state of the pin 301 on the vertical plate 5. The four corner plates are fixed to the inner wall of the pin 301, serving as the bearing base of the spring 304. Compared to directly welding the spring 304 to the inner wall of the pin 301, the planar structure of the four corner plates can increase the contact area of ​​the spring 304, preventing the spring 304 from becoming eccentric, tilting, or falling off due to vibration. The vertical plate 5 is fixed to the outer wall of the sliding sleeve 4, and the vertical groove 8 is opened on the inner wall of the pipe 1. The two are engaged to achieve circumferential rotation limit of the sliding sleeve 4 and the pipe 1, preventing the sliding sleeve 4 from rotating under the impact of fracturing fluid, ensuring the coaxiality of the ball seat inside the sliding sleeve 4 and the ball 7, and avoiding sealing failure caused by the misalignment of the ball 7. The rubber rings on the inner walls of the first circular hole 9 and the second circular hole 6 can fill the gap between the pin 301 and the hole wall, preventing fracturing fluid and formation fluid in the wellbore from seeping into the gap between the pipe 1 and the sliding sleeve 4 through the channel, and avoiding corrosion of the sliding sleeve 4 or jamming of the mechanism caused by fluid leakage.

[0035] Please see Figure 6 and Figure 7 The outer side of the pipe 1 is provided with an external thread, and the outer side of the pipe 1 is connected to a secondary locking component 10 through the external thread. The secondary locking component 10 is used to prevent the positioning block 303 from falling off.

[0036] The secondary locking assembly 10 includes a rotating collar 101, which has multiple threaded holes, and each threaded hole is threaded with a locking bolt 102.

[0037] Each positioning block 303 has a fixing hole that matches the threaded hole 1, and the number of threaded holes 1 is the same as the number of fixing holes.

[0038] By using the external thread on the outside of the pipe 1, the rotating collar 101 can rotate up and down in the pipe 1. After the positioning block 303 is tightened, the rotating collar 101 is rotated to move downward, so that each threaded hole on the rotating collar 101 corresponds to the fixing hole on each positioning block 303. Then, the locking bolt 102 is screwed into the threaded hole. Since the threaded hole corresponds to the fixing hole, the locking bolt 102 enters the fixing hole to fix the positioning block 303, thereby preventing the positioning block 303 on the pin 301 from falling off, and realizing the secondary locking of the positioning block 303.

[0039] Working principle: The connector 2 serves as the connection between the pipeline 1 and the downhole tubing string, ensuring a rigid connection and sealing performance between the sliding sleeve 4 and the tubing string. This prevents fracturing fluid leakage from the connection point. The standardized connector structure is adaptable to different specifications of downhole tubing strings, enhancing the versatility of the sliding sleeve 4. The pin 301 penetrates the outer wall of the pipeline 1 and extends into the inner wall, engaging with a pre-set positioning groove on the outer wall of the sliding sleeve 4. The positioning block 303 is threaded to the end of the pin 301, allowing for fine-tuning of the pin 301's insertion depth and precise locking of the axial position of the sliding sleeve 4 within the pipeline 1. This prevents the sliding sleeve 4 from shifting due to downhole fluid impact or tubing string vibration, ensuring safe operation. The coaxiality of ball 7 during setting is ensured by the locking block 302 hinged to the exposed end of pin 301. The locking block 302 can rotate around the hinge point. After the sliding sleeve 4 is installed in place, the locking block 302 is rotated to engage with the groove or limiting platform on the inner wall of the tube column, further enhancing the overall impact resistance and stability of the sliding sleeve 4 and preventing it from shifting under high pressure. The button 306, the round tube 305, and the spring 304 form an elastic unlocking mechanism. Under normal operating conditions, the elastic force of the spring 304 pushes the round tube 305 to press against the inside of pin 301, ensuring that the threaded connection between pin 301 and positioning block 303 is locked and preventing the threads from loosening. After the positioning block 303 is tightened, the locking mechanism is activated by rotating the button 306. The collar 101 moves downwards, aligning each threaded hole on the collar 101 with the fixing hole on each positioning block 303. Then, the locking bolt 102 is screwed into the threaded hole. Because the threaded hole aligns with the fixing hole, the locking bolt 102 enters the fixing hole and secures the positioning block 303, preventing it from falling off the pin 301 and achieving secondary locking of the positioning block 303. When the sliding sleeve 4 needs to be disassembled for maintenance, the locking bolt 102 is unscrewed to release the secondary locking. Then, pressing the button 306 compresses the spring 304, causing the round tube 305 to retract. The locking state of pin 301 can be quickly released, and pin 301 can be pulled out by unscrewing the positioning block 303, realizing the quick disassembly of the sliding sleeve 4 without cutting, which greatly reduces the later maintenance cost. As the core component for bearing and guiding the ball 7, the sliding sleeve 4 provides a setting space for the ball 7 in its internal chamber. When the ball 7 is set in the sliding sleeve 4 with the fracturing fluid, the pressure on the ground can push the sliding core inside the sliding sleeve 4 to move, opening the fracturing fluid flow channel and realizing the fracturing transformation of the target reservoir. The ball 7 achieves sealing and pressure holding by precisely fitting with the ball seat inside the sliding sleeve 4. Different sizes of ball 7 can be matched with sliding sleeves 4 of different sections to meet the needs of staged fracturing.

[0040] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. An improved structure for a ball-feeding sliding sleeve in an oil well, comprising a pipeline (1), characterized in that: Both ends of the pipe (1) are fixedly connected to connectors (2), the outer wall of the pipe (1) is provided with multiple sets of locking components (3), the inside of the pipe (1) is installed with a sliding sleeve (4), and the inside of the sliding sleeve (4) is provided with a ball (7). The multiple sets of the engagement components (3) include a pin (301), one end of which penetrates into the inner wall of the pipe (1), a positioning block (303) is threaded onto one end of the pin (301), a locking block (302) is hinged to the other end of the pin (301), a button (306) is provided on one end of the pin (301), a round tube (305) is fixedly connected to one end of the button (306), the round tube (305) moves inside the pin (301), and a spring (304) is connected to one end of the round tube (305). The outer side of the pipe (1) is provided with an external thread, and the outer side of the pipe (1) is connected to a secondary locking component (10) by the external thread. The secondary locking component (10) is used to prevent the positioning block (303) from falling off.

2. The improved structure of the downhole ball-feeding sliding sleeve according to claim 1, characterized in that: The secondary locking assembly (10) includes a rotating collar (101), which has multiple threaded holes, and each threaded hole is threaded with a locking bolt (102).

3. The improved structure of the downhole ball-feeding sliding sleeve according to claim 1, characterized in that: Each of the positioning blocks (303) is provided with a fixing hole that matches the threaded hole one, and the number of the threaded holes one is the same as the number of fixing holes.

4. The improved structure of the downhole ball-feeding sliding sleeve according to claim 1, characterized in that: The outer wall of the pipe (1) is provided with a plurality of first round holes (9), and one end of the pin (301) passes through the interior of the first round hole (9).

5. The improved structure of the downhole ball-feeding sliding sleeve according to claim 2, characterized in that: The other end of the pin (301) has a keyway, and the positioning block (303) is installed inside the keyway.

6. The improved structure of the downhole ball-feeding sliding sleeve according to claim 3, characterized in that: One end of the spring (304) is fixedly connected to a four-corner plate, which is fixedly connected to the inner wall of the pin (301).

7. The improved structure of the downhole ball-feeding sliding sleeve according to claim 4, characterized in that: The outer wall of the sliding sleeve (4) is fixedly connected to a vertical plate (5), and the inside of the pipe (1) is provided with a vertical groove (8), and the vertical plate (5) is engaged inside the vertical groove (8).

8. The improved structure of the downhole ball-feeding sliding sleeve according to claim 5, characterized in that: The surface of the vertical plate (5) is provided with a second circular hole (6), and the first circular hole (9) and the second circular hole (6) are symmetrical to each other.

9. An improved structure for a downhole ball-feeding sliding sleeve in oil wells according to claim 6, characterized in that: Both the inner walls of the first circular hole (9) and the second circular hole (6) are provided with rubber rings.

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