Soluble bridge plug with plug-in type locking mechanism

Abstract

The utility model provides a soluble bridge plug with a plug-in type locking mechanism, and relates to the technical field of downhole tools in the petroleum and natural gas industry, the soluble bridge plug with the plug-in type locking mechanism comprises a cone, a sealing ring, a slip and a guiding shoe; the cone is in a cone frustum shape, an axially-arranged channel is formed in the cone, the sealing ring is arranged on the outer wall of the cone in a sleeving mode, the slip is arranged at one end of the top face of the cone in a sleeving mode, and the guiding shoe is located at the end, back to the cone, of the slip and connected with the slip. The inner wall of the cone is provided with first threaded teeth, the outer wall of the guide shoe is provided with second threaded teeth, and by arranging the first threaded teeth and the second threaded teeth, after setting, the cone and the guide shoe of the bridge plug are locked mutually, the whole bridge plug is not prone to being separated, the whole structure of the bridge plug is more stable after setting, and the situation that due to pressure fluctuation, the bridge plug is damaged is effectively avoided. Compared with other single-slip bridge plugs, the single-slip soluble bridge plug can bear a part of upward pressure from the bottom of a well, and can be comparable with a double-slip soluble bridge plug.

Description

Technical Field

[0001] The utility model relates to the technical field of downhole tools in the oil and gas industry, in particular to a soluble bridge plug with an inserted locking mechanism. Background Art

[0002] In oil and gas well production enhancement operations, the most commonly used measure is fracturing. Soluble bridge plug fracturing is characterized by high efficiency, safety, and lower construction cost.

[0003] In 2020, the market size of China's soluble fracturing bridge plugs reached 137 million yuan, and it is expected to reach 372 million yuan in 2027, with a compound annual growth rate (CAGR) of 14.19% in the next few years (2021-2027). The development of China's soluble bridge plug market benefits from the development of shale gas. Shale gas refers to unconventional natural gas that exists in organic-rich mudstone and its interlayers, and exists mainly in adsorption or free state. It is mainly composed of methane and is a clean and efficient energy source. The application value of shale gas Shale gas is natural gas extracted from shale layers. Its composition and uses are the same as conventional natural gas, and it is a substitute for conventional natural gas. Shale gas can replace coal for factory heating, production boilers, thermal power plant gas turbine boilers, power generation, residential fuel, chemical industry, etc., and can also replace automobile oil, etc. With the growth of China's proven shale gas reserves and the country's attention to shale gas, the market will continue to grow in the future. The diameter of the soluble fracturing plug is usually between 4.5 and 5.5 inches, and the length is between 22 and 30 inches. A single wellbore requires 10 to 40 multi-component fracturing plugs to pressurize and perforate multiple oil and gas production layers. The soluble bridge plug technology achieves full bore of the wellbore without any intervention, effectively solving the problem that fast-drilling composite bridge plugs rely on continuous tubing drilling and large-diameter bridge plugs cannot meet production logging requirements, and adapts to the development trend of staged fracturing of horizontal wells in my country's oil and gas wells.

[0004] After extensive use of soluble bridge plugs for oil and gas well fracturing operations, the applicant found that after the single-slip soluble bridge plug was set, the bridge plug was affected by pressure fluctuations, and the cone and the guide shoe (leader) were easily separated by pressure, resulting in failure of the bridge plug.

[0005] The prior patent CN2023205951972 has been published. Utility Model Content

[0006] In view of the deficiencies in the prior art, the present application provides a soluble bridge plug with an insertable locking mechanism.

[0007] The present application discloses a soluble bridge plug with an insert-type locking mechanism, comprising: a cone, a sealing ring, a slip and a guide shoe; the cone is in the shape of a truncated cone, an axially arranged channel is provided inside the cone, the sealing ring is sleeved on the outer wall of the cone, the slip is sleeved on one end of the top surface of the cone, the guide shoe is located at the end of the slip facing away from the cone, and is connected to the slip; the inner wall of the cone has a first thread tooth, and the outer wall of the guide shoe has a second thread tooth, and when the cone is connected to the guide shoe, the cone and the guide shoe form a one-way moving fit.

[0008] Preferably, the outer wall of the cone has third thread teeth, the inner wall of the slip has fourth thread teeth, the cone and the slip form a one-way moving fit, and the one-way moving direction of the cone relative to the slip is the same as that of the guide shoe.

[0009] Preferably, the guide shoe includes a guide ring and a pawl, the guide ring is located at one end of the slip facing away from the cone and abuts against the slip, the pawl is located between the guide ring and the cone and connected to the guide ring, the slip is sleeved outside the pawl, and the second threaded tooth is located on the outer wall of the pawl.

[0010] Preferably, the outer wall ring of the pawl is provided with a first boss, the inner wall of the slip is provided with a second boss, and the first boss is located between the second boss and the guide ring.

[0011] Preferably, the pawl includes a fixed part and an elastic part, the fixed part is connected to the guide ring, the first boss is located on the fixed part, the second thread tooth is located on the elastic part, and the elastic part has a slit extending from the direction of the fixed part away from the guide ring to the direction of the fixed part close to the guide ring.

[0012] Preferably, the number of the slits is 4-8.

[0013] Preferably, the slit extends from an end of the fixing portion facing away from the guide ring to an end of the fixing portion facing the guide ring.

[0014] Preferably, the plurality of slits are distributed at equal intervals.

[0015] Preferably, the pawl has a guide member, which is arranged around the pawl, and the outer diameter of the guide member gradually increases from the direction of the pawl facing away from the guide ring to the direction of the pawl facing the guide ring.

[0016] Preferably, the first thread teeth and the second thread teeth each have multiple turns.

[0017] The beneficial effects of the present application are as follows: by setting the first thread teeth and the second thread teeth, the cone and the guide shoe of the bridge plug are locked with each other after setting, and the bridge plug as a whole is not easy to separate. The overall structure of the bridge plug is more stable after setting, which effectively avoids the failure caused by the separation of the parts of the bridge plug due to pressure fluctuations, and the quality is more reliable. Compared with other single-cava bridge plugs, it can withstand part of the pressure from the bottom of the well, which is comparable to the double-cava soluble bridge plug. In addition, the soluble bridge plug with the insert-type locking mechanism has a simple structure. On the premise of ensuring product quality and reliable performance, the production cost is lower, achieving the strategy of reducing costs and increasing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0019] Figure 1 A three-dimensional diagram of a soluble bridge plug with an insert-type locking mechanism in an embodiment;

[0020] Figure 2 A cross-sectional view of a soluble bridge plug with an insert-type locking mechanism in an embodiment;

[0021] Figure 3 A cross-sectional view of a cone in an embodiment;

[0022] Figure 4 A three-dimensional diagram of a shoe in the embodiment;

[0023] Figure 5 A cross-sectional view of a shoe in an embodiment;

[0024] Figure 6 2 is a cross-sectional view of the slip in the embodiment.

[0025] Reference numerals:

[0026] 1- cone; 2- sealing ring; 3- slip; 4- guide shoe;

[0027] 11-first thread tooth; 13-third thread tooth;

[0028] 31- fourth thread tooth; 32- second boss;

[0029] 41-lead ring; 42-ratchet;

[0030] 421 - first boss; 422 - fixing portion; 423 - elastic portion; 424 - flow guide; 425 - second thread tooth; 4221 - slit. DETAILED DESCRIPTION

[0031] The following will disclose multiple embodiments of the present application with drawings. For the purpose of clear description, many practical details will be described together in the following description. However, it should be understood that these practical details should not be used to limit the present application. In other words, in some embodiments of the present application, these practical details are not necessary. In addition, in order to simplify the drawings, some conventional structures and components will be depicted in a simple schematic manner in the drawings.

[0032] It should be noted that all directional indications such as up, down, left, right, front, back... in the embodiments of the present application are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture as shown in the accompanying drawings. If the specific posture changes, the directional indication will also change accordingly.

[0033] In addition, in the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes, and do not specifically refer to the order or sequence, nor are they used to limit the present application. They are only used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present application.

[0034] In order to further understand the application content, features and effects of the present application, the following embodiments are cited and described in detail with reference to the accompanying drawings.

[0035] Please refer to Tu 1, Figure 1 It is a three-dimensional diagram of a soluble bridge plug with an insertable locking mechanism. The soluble bridge plug with an insertable locking mechanism in this example includes a cone 1, a sealing ring 2, a slip 3 and a guide shoe 4. The cone 1 is used to carry the soluble fracturing ball and the sealing ring 2, the slip 3 is used to anchor the casing wall, and the guide shoe 4 is used to prevent the equipment from colliding with the well wall and acts as a grab hook.

[0036] Please also read Figures 2 to 5 , Figure 2 This is a cross-sectional view of a soluble bridge plug with an insert-type locking mechanism. Figure 3 is a cone section view. Figure 4 To guide the three-dimensional diagram of the shoe, Figure 5 It is a cross-sectional view of the guide shoe, in which the cone 1 is in the shape of a truncated cone with an axially arranged channel inside. The cone 1, sealing ring 2, slipper 3 and guide shoe 4 are arranged in sequence, the sealing ring 2 is sleeved on the outer wall of the cone 1, the slipper 3 is sleeved on one end of the top surface of the cone 1, and the guide shoe 4 is located at the end of the slipper 3 facing away from the cone 1 and is connected to the slipper 3; the inner wall of the cone 1 has a first thread tooth 11, and the outer wall of the guide shoe 4 has a second thread tooth 425. When the cone 1 is connected to the guide shoe 4, the cone 1 and the guide shoe 4 form a unidirectional moving fit.

[0037] Specifically, the first thread tooth 11 has an a surface and a b surface, which are respectively located on opposite sides of the first thread tooth 11, and the a surface is located on the side of the first thread tooth 11 facing away from the guide shoe 4, and the b surface is located on the side of the first thread tooth 11 facing the guide shoe 4. The angle between the b surface and the outer wall surface of the cone 1 is an acute angle, and the angle between the a surface and the outer wall surface of the cone 1 is a right angle; the second thread tooth 425 has a c surface and a d surface, which are respectively located on opposite sides of the second thread tooth 425, and the c surface is located on the side of the second thread tooth 425 facing the cone 1, and the d surface is located on the side of the second thread tooth 425 facing away from the cone 1. The angle between the c surface and the outer wall surface of the guide shoe 4 is an acute angle, and the angle between the d surface and the outer wall surface of the guide shoe 4 is a right angle. When the cone 1 is connected to the guide shoe 4, the cone 1 and the guide shoe 4 form a unidirectional moving fit, that is, when the cone 1 and the guide shoe 4 are connected, there is only a tendency for the relative distance to decrease.

[0038] In this example, a sealing surface is provided in the cavity at the upper end of the cone 1. After the soluble bridge plug is set, the soluble fracturing ball is placed to form a seal with the sealing surface. A screw hole is provided at the upper end of the cone 1. A set screw is installed to fix the cone 1 and the adapter. The screw has a fixed shear value to prevent premature setting. The taper of the inner side of the soluble metal sealing ring 2 is consistent with the cone 1 on the outer side of the cone 1. After the soluble bridge plug is set, the inner side of the soluble metal sealing ring 2 is sealed with the cone surface of the cone 1, and the outer side of the soluble metal sealing ring 2 is sealed with the downhole casing. The soluble metal sealing ring 2 is a spiral structure. During the setting process, the soluble metal sealing ring 2 is radially expanded. The taper of the inner side of the slip 3 is consistent with the taper of the outer side of the cone 1. The taper is consistent, the surface of the cone 1 is in close contact with the inner side of the slip 3, and the cone 1 supports the slip 3; the outer side of the slip 3 is provided with a slip tooth hole for installing the slip teeth, and after the soluble bridge plug is sealed, the slip teeth anchor the casing wall; the guide shoe 4 is provided with a shear ring for releasing, and the shear ring is connected to the pull rod of the adapter. After the soluble bridge plug is sealed, the releasing shear ring on the guide shoe 4 is sheared to separate the soluble bridge plug from the adapter, thereby completing the release; the slip teeth are made of insoluble material, and the cone 1, sealing ring 2, guide shoe 4 and the remaining structures of the slip 3 are made of soluble materials. After the bridge plug is sealed underground, it can be completely soluble after soaking for a period of time, and will not affect subsequent production work.

[0039] In specific applications, when the bridge plug is pumped to the designed position underground, the sealing tool starts to work. During the sealing process, the adapter push tube pushes the cone 1 of the soluble bridge plug, the set screw is sheared off, and the adapter push tube moves together with the cone 1 toward the guide shoe 4. The soluble metal sealing ring 2 rotates circumferentially and expands without obvious displacement, the slip 3 opens radially without obvious displacement, and the guide shoe 4 has no obvious displacement until the outer diameter of the soluble metal sealing ring 2 is in close contact with the inner wall of the casing, and the inner diameter is in close contact with the conical surface of the cone 1. At this time, the soluble metal sealing ring 2 is tightly closed. The annular space between the inner wall of the casing and the conical surface of the cone 1 is sealed; the slips 3 are radially opened synchronously, and the slip teeth are embedded in the casing wall to anchor the bridge plug as a whole. After the release force is reached, the shear ring on the guide shoe 4 is sheared off, and the adapter is separated from the soluble bridge plug, the shear release is completed, the setting tool is lifted up, and the setting tool is pulled out to the wellhead, and a soluble fracturing ball is dropped into the well. After the soluble fracturing ball reaches the sealing surface of the cone 1, the soluble bridge plug seals the upper and lower positions of the bridge plug; high-pressure fluid is pumped toward the upper part of the bridge plug to start the fracturing operation.

[0040] In this way, by setting the first thread teeth 11 and the second thread teeth 425, the cone 1 and the guide shoe 4 of the bridge plug are locked with each other after setting, and the bridge plug as a whole is not easy to separate. The overall structure of the bridge plug is more stable after setting, which effectively avoids the failure caused by the separation of the parts of the bridge plug due to pressure fluctuations. The quality is more reliable. Compared with other single-cava 3 bridge plugs, it can withstand part of the upward pressure from the bottom of the well, which is comparable to the double-cava 3 soluble bridge plug. In addition, the soluble bridge plug with the insert-type locking mechanism has a simple structure. Under the premise of ensuring product quality and reliable performance, the production cost is lower, achieving the strategy of reducing costs and increasing efficiency.

[0041] In addition to the above, please refer to Figure 6 , Figure 6 It is a cross-sectional view of the slip, the outer wall of the cone 1 has a third thread tooth 13, the inner wall of the slip 3 has a fourth thread tooth 31, the cone 1 and the slip 3 form a one-way moving fit, and the one-way moving direction of the cone 1 relative to the slip 3 and the guide shoe 4 is the same, that is, the relative distance between the cone 1 and the slip 3 only tends to decrease.

[0042] Specifically, the matching principle between the third thread teeth 13 and the fourth thread teeth 31 is the same as the matching principle between the first thread teeth 11 and the second thread teeth 425 , which will not be elaborated herein.

[0043] Furthermore, the first thread teeth 11 , the second thread teeth 425 , the third thread teeth 13 and the fourth thread teeth 31 all have multiple turns.

[0044] Furthermore, the guide shoe 4 includes a guide ring 41 and a pawl 42. The guide ring 41 is located at the end of the cava 3 facing away from the cone 1 and abuts against the cava 3. The pawl 42 is located between the guide ring 41 and the cone 1 and is connected to the guide ring 41. The cava 3 is sleeved outside the pawl 42, and the second thread tooth 425 is located on the outer wall of the pawl 42.

[0045] In this way, the guide ring 41 is connected to the adapter, the pawl 42 can extend into the axial channel of the cone 1 and connect with the inner wall of the cone 1. After setting, the pawl 42 and the cone 1 are locked in one direction.

[0046] Furthermore, a first boss 421 is provided on the outer wall of the pawl 42 , and a second boss 32 is provided on the inner wall of the slip 3 . The second boss 32 is located between the first boss 421 and the guide ring 41 .

[0047] In this way, the first boss 421 and the second boss 32 are limitedly matched, and the second boss 32 blocks the first boss 421 , thereby fixing the guide shoe 4 .

[0048] Furthermore, the pawl 42 includes a fixed portion 422 and an elastic portion 423, the fixed portion 422 is connected to the guide ring 41, the first boss 421 is located at the fixed portion 422, the second thread tooth 425 is located at the elastic portion 423, and the elastic portion 423 has a slit 4221, which extends from the direction of the fixed portion 422 away from the guide ring 41 to the direction of the fixed portion 422 close to the guide ring 41.

[0049] In this way, the slit 4221 makes the elastic portion 423 elastic, and the one-way locking effect between the pawl 42 and the cone 1 is better.

[0050] Specifically, there are 4-8 slits 4221; the slits 4221 extend from one end of the fixed portion 422 facing away from the guide ring 41 to the end of the fixed portion 422 facing the guide ring 41. It should be noted that the fewer the slits 4221, the greater the elasticity of the elastic portion 423, and the longer the slits 4221, the greater the elasticity of the elastic portion 423.

[0051] Furthermore, the plurality of slits 4221 are distributed at equal intervals.

[0052] Furthermore, the pawl 42 has a guide member 424 , which is arranged around the pawl 42 , and the outer diameter of the guide member 424 gradually increases from the direction of the pawl 42 facing away from the guide ring 41 to the direction of the pawl 42 facing the guide ring 41 .

[0053] In this way, the guide member 424 can be used to guide the direction in which the slips 3 open.

[0054] In summary, by setting the first thread teeth and the second thread teeth, the cone and the guide shoe of the bridge plug are locked with each other after setting, and the bridge plug as a whole is not easy to separate. The overall structure of the bridge plug is more stable after setting, which effectively avoids the failure caused by separation of parts of the bridge plug due to pressure fluctuations. The quality is more reliable. Compared with other single-cava bridge plugs, it can withstand part of the upward pressure from the bottom of the well, which is comparable to the double-cava soluble bridge plug. In addition, the soluble bridge plug with the insert-type locking mechanism has a simple structure. Under the premise of ensuring product quality and reliable performance, the production cost is lower, achieving the strategy of reducing costs and increasing efficiency.

[0055] The above is only the implementation mode of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A soluble bridge plug with an insert-type locking mechanism, characterized in that: The invention comprises a cone (1), a sealing ring (2), a slipper (3) and a guide shoe (4); the cone (1) is in the shape of a truncated cone, and an axially arranged channel is arranged inside the cone; the sealing ring (2) is sleeved on the outer wall of the cone (1); the slipper (3) is sleeved on one end of the top surface of the cone (1); the guide shoe (4) is located at the end of the slipper (3) facing away from the cone (1) and is connected to the slipper (3); the inner wall of the cone (1) has a first thread tooth (11), and the outer wall of the guide shoe (4) has a second thread tooth (425); when the cone (1) and the guide shoe (4) are connected, the cone (1) and the guide shoe (4) form a one-way movable fit.

2. The soluble bridge plug with an insert-type locking mechanism according to claim 1, characterized in that: The outer wall of the cone (1) has third thread teeth (13), the inner wall of the slip (3) has fourth thread teeth (31), the cone (1) and the slip (3) form a one-way moving fit, and the one-way moving direction of the cone (1) relative to the slip (3) is the same as that of the guide shoe (4).

3. The soluble bridge plug with an insert-type locking mechanism according to claim 1, characterized in that: The guide shoe (4) comprises a guide ring (41) and a pawl (42); the guide ring (41) is located at one end of the slip (3) facing away from the cone (1) and is in contact with the slip (3); the pawl (42) is located between the guide ring (41) and the cone (1) and is connected to the guide ring (41); the slip (3) is sleeved outside the pawl (42); and the second threaded tooth (425) is located on the outer wall of the pawl (42).

4. The soluble bridge plug with an insert-type locking mechanism according to claim 3, characterized in that: The outer wall ring of the ratchet (42) is provided with a first boss (421), the inner wall of the slip (3) is provided with a second boss (32), and the first boss (421) is located between the second boss (32) and the guide ring (41).

5. The soluble bridge plug with insert-type locking mechanism according to claim 4, characterized in that: The pawl (42) includes a fixed portion (422) and an elastic portion (423), the fixed portion (422) is connected to the guide ring (41), the first boss (421) is located on the fixed portion (422), the second threaded tooth (425) is located on the elastic portion (423), and the elastic portion (423) has a slit (4221), and the slit (4221) extends from the direction of the fixed portion (422) away from the guide ring (41) to the direction of the fixed portion (422) close to the guide ring (41).

6. The soluble bridge plug with insert-type locking mechanism according to claim 5, characterized in that: The number of the slits (4221) is 4 to 8.

7. The soluble bridge plug with an insert-type locking mechanism according to claim 5, characterized in that: The slit (4221) extends from an end of the fixing portion (422) facing away from the guide ring (41) to an end of the fixing portion (422) facing the guide ring (41).

8. The soluble bridge plug with an insert-type locking mechanism according to claim 6, characterized in that: The plurality of slits (4221) are distributed at equal intervals.

9. The soluble bridge plug with an insert-type locking mechanism according to claim 3, characterized in that: The ratchet (42) has a guide piece (424) which is arranged around the ratchet (42). The outer diameter of the guide piece (424) gradually increases from the direction of the ratchet (42) facing away from the guide ring (41) to the direction of the ratchet (42) facing the guide ring (41).

10. The soluble bridge plug with an insert-type locking mechanism according to claim 1, characterized in that: The first thread teeth (11) and the second thread teeth (425) both have multiple turns.

Images