Wellhead reconstruction tool and wellhead reconstruction system

Abstract

This disclosure provides a wellhead reconstruction tool and a wellhead reconstruction system. The wellhead reconstruction tool includes: a tool body with an internal cavity; a first flange connected to the top of the tool body for connection to a blowout preventer (BOP); a connecting part at the bottom of the tool body for connection to a second flange of the well; and a piston disposed within the cavity, with a channel formed inside the piston for moving towards or away from the second flange. When the piston moves to contact the second flange, a sealing connection is formed between the tool body and the second flange. The wellhead reconstruction tool is suitable for situations where the distance between the second flange and the BOP is small, or where the outer side of the second flange has a set screw or grease injection port structure, even when the second flange or the second flange is intact. Remote control via an automated handling tool and an automated robotic arm enables rapid completion of wellhead reconstruction operations, improving safety.

Description

Technical Field

[0001] This disclosure relates to the field of well workover equipment technology, and in particular to a wellhead reconstruction tool and a wellhead reconstruction system. Background Technology

[0002] Well workover operations are a crucial technical means to ensure the normal production of oil, gas, and water wells during oilfield exploration and development. However, as oilfield development progresses into its later stages, the number of wells with hidden problems increases annually, exposing various well control issues during well production operations. A review and statistical analysis of well control emergency rescue incidents reveals that for blowouts with intact flanges, current emergency rescue techniques can only be applied to the casing bottom flange. However, for cases where the blowout preventer (BOP) or wellhead flange is intact, the small distance between the finished BOP and the original well flange, or the presence of set screws or grease injection holes on the outside of the original well flange, limits the usability of relevant wellhead reconstruction tools due to size constraints.

[0003] Therefore, it is necessary to propose a wellhead reconstruction tool and a wellhead reconstruction system to at least partially solve the problems existing in the prior art. Summary of the Invention

[0004] This disclosure aims to address at least one of the technical problems existing in the prior art or related technologies.

[0005] Therefore, the first aspect of this disclosure provides a wellhead reconstruction tool;

[0006] A second aspect of this disclosure provides a wellhead reconstruction system.

[0007] In view of this, a wellhead reconstruction tool is provided according to a first aspect of the present disclosure, comprising:

[0008] The tool body has a cavity formed inside it;

[0009] A first flange is connected to the top of the tool body and is used to connect to the blowout preventer.

[0010] The connecting part, at the bottom of the tool body, is used to connect to the second flange of the oil well via the connecting part;

[0011] A piston is disposed in the cavity, and a channel is formed inside the piston. The piston is used to move toward or away from the second flange. When the piston moves to fit against the second flange, a sealed connection is formed between the tool body and the second flange.

[0012] In one feasible implementation, the main body of the above-mentioned tool includes:

[0013] Hydraulic cylinder;

[0014] A hydraulic cylinder cover is disposed inside the aforementioned hydraulic cylinder and sleeved on the aforementioned piston;

[0015] The piston has a boss at one end away from the first flange, and an annular space is formed between the top of the hydraulic cylinder head and the boss. One of the piston, the hydraulic cylinder, and the hydraulic cylinder head has a hydraulic oil passage along the axial direction, and the hydraulic oil passage is connected to the annular space.

[0016] In one feasible implementation, it further includes:

[0017] The first sealing ring is disposed in the first sealing ring groove provided on the side wall of the piston, and the first sealing ring is located above the annular space.

[0018] The second sealing ring is disposed in the second groove provided on the side wall of the piston, and the second sealing ring is located below the annular space.

[0019] In one feasible implementation, it further includes:

[0020] A sealing assembly is used to cooperate with the piston to seal the second flange.

[0021] In one feasible implementation, the sealing assembly includes:

[0022] The third sealing ring is disposed at the end of the piston away from the first flange. When the piston and the second flange are in contact, the third sealing ring is inserted into the third groove of the second flange.

[0023] The fourth sealing ring is disposed at the end of the piston away from the first flange. Along the radial direction of the piston, the fourth sealing ring is located inside the third sealing ring. When the piston and the second flange are in contact, the fourth sealing ring is compressed and deformed and adheres tightly to the piston and the second flange.

[0024] In one feasible implementation, the connecting portion includes:

[0025] The hook claw is used to fit the end of the hydraulic cylinder away from the first flange onto the second flange. The hook claw is connected to the inner wall of the end of the hydraulic cylinder away from the first flange by an elastic element. The end of the hook claw facing the first flange is provided with a hook groove.

[0026] When the second flange is engaged with the groove, the elastic element is in a compressed state.

[0027] In one feasible implementation, a chamfer is provided on the inner side of the end of the hook that is away from the first flange.

[0028] In one feasible implementation, the connecting portion includes:

[0029] Multiple retrieval spears are disposed at the end of the piston opposite to the first flange, and the multiple retrieval spears are used to correspond to the multiple threaded holes of the second flange;

[0030] When the piston is in contact with the second flange, the spear is inserted into the threaded hole and engaged with the inner wall of the threaded hole; when the piston moves away from the second flange, the spear retracts from the threaded hole.

[0031] A wellhead reconstruction system is provided according to a second aspect of the embodiments of this disclosure, comprising:

[0032] As described in any of the above technical solutions, the wellhead reconstruction tool body of the wellhead reconstruction tool includes: a hydraulic cylinder; a hydraulic cylinder cover disposed inside the hydraulic cylinder and sleeved on the piston; wherein, a boss is provided at the end of the piston away from the first flange, an annular space is formed between the top of the hydraulic cylinder cover and the boss, and a hydraulic oil passage is provided along the axial direction for one of the piston, the hydraulic cylinder and the hydraulic cylinder cover, and the hydraulic oil passage is connected to the annular space;

[0033] A drive unit is used to transport the aforementioned wellhead reconstruction tools to the wellhead.

[0034] A robotic arm is used to install the aforementioned wellhead reconstruction tool onto the aforementioned second flange;

[0035] Blowout preventer, connected to the first flange before the drive unit transports the wellhead reconstruction tool;

[0036] The hydraulic injection pipeline has an injection hole on the first flange, which is connected to the hydraulic circuit. The hydraulic oil from the hydraulic source is delivered to the hydraulic circuit through the hydraulic injection pipeline.

[0037] Both the aforementioned drive unit and the robotic arm are remotely controlled.

[0038] In one feasible implementation, the length of the aforementioned hydraulic injection pipeline is greater than 25m.

[0039] Compared to existing technologies, this disclosure offers at least the following advantages: The wellhead reconstruction tool provided in this embodiment comprises a tool body, a first flange, a connecting portion, and a piston. The tool body has a cavity, the piston is disposed within the cavity, and the bottom of the tool body is connected to the second flange at the wellhead via the connecting portion. The piston can move within the cavity towards or away from the second flange. When the piston moves to abut against the second flange, the piston and the second flange fit together to form a sealed connection. Furthermore, a passage is formed inside the piston, connecting the piston passage, the first flange passage, and the second flange passage, thereby enabling operations such as draining fluid from the well through the tool body. A blowout preventer (BOP) can be connected to the top of the tool body. Closing the BOP's full-seal gate seals the piston passage, the first flange passage, and the second flange passage, achieving rapid blowout prevention. After blowout control, it can be directly connected to pressurized equipment or coiled tubing, facilitating subsequent high-density workover fluid flushing and well control to completely eliminate blowout. Wellhead reconstruction tools are suitable for situations where the second flange or blowout preventer is intact, and where the distance between the second flange and the blowout preventer is small, or where the outer side of the second flange has a set screw or grease injection hole structure. By using automatic handling tools and automatic robotic arms, the wellhead reconstruction operation can be completed quickly and remotely, improving safety. Attached Figure Description

[0040] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of exemplary embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this disclosure. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0041] Figure 1 One of the schematic assembly drawings of a wellhead reconstruction tool and a second flange according to an embodiment of this disclosure;

[0042] Figure 2 This is a second schematic assembly diagram of a wellhead reconstruction tool and a second flange according to an embodiment of this disclosure;

[0043] Figure 3 This is a schematic assembly diagram of a wellhead reconstruction tool, a blowout preventer, and a second flange, according to one embodiment of this disclosure.

[0044] in, Figures 1 to 3 The correspondence between the reference numerals and component names in the attached drawings is as follows:

[0045] 100 Wellhead reconstruction tool, 110 Tool body, 111 Hydraulic cylinder, 112 Hydraulic cylinder cover, 113 Annulus, 114 Hydraulic circuit, 120 First flange, 130 Connecting part, 131 Hook, 1311 Hook groove, 132 Elastic element, 133 Retriever, 140 Piston, 150 First sealing ring, 160 Second sealing ring, 170 Sealing assembly, 171 Third sealing ring, 172 Fourth sealing ring, 200 Second flange, 210 Blowout preventer. Detailed Implementation

[0046] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0047] like Figures 1 to 3 As shown, a wellhead reconstruction tool 100 is provided according to a first aspect embodiment of the present disclosure, comprising: a tool body 110, the tool body 110 having a cavity formed inside; a first flange 120 connected to the top of the tool body 110, the first flange 120 being used to connect to a blowout preventer 210; a connecting portion 130, the bottom of the tool body 110 being used to connect to a second flange 200 of an oil well via the connecting portion 130; and a piston 140 disposed in the cavity, the piston 140 having a channel formed inside, the piston 140 being used to move toward or away from the second flange 200, wherein when the piston 140 moves to fit against the second flange 200, a sealed connection is formed between the tool body 110 and the second flange 200.

[0048] It is understood that this disclosure includes at least the following beneficial effects: The wellhead reconstruction tool 100 provided in the embodiments of this disclosure is provided with a tool body 110, a first flange 120, a connecting part 130, and a piston 140. The tool body 110 forms a cavity, the piston 140 is disposed within the cavity, and the bottom of the tool body 110 is connected to the second flange 200 of the wellhead via the connecting part 130. The piston 140 can move within the cavity towards or away from the second flange 200. When the piston 140 moves to abut against the second flange 200, the piston 140 and the second flange 200 fit together to form a sealed connection. Furthermore, a passage is formed inside the piston 140, connecting the passage of the piston 140, the passage of the first flange 120, and the passage of the second flange 200, thereby enabling operations such as draining fluid from the wellhead to be performed through the tool body 110. Furthermore, the structure at the top of the tool body 110 can be connected to the blowout preventer 210. After connecting the wellhead reconstruction tool 100 and the blowout preventer 210, the wellhead reconstruction tool 100 is connected to the second flange 200. By closing the full-sealing gate of the blowout preventer 210, the passages of the piston 140, the first flange 120, and the second flange 200 can be sealed to achieve rapid blowout prevention. After the blowout is controlled, it can be directly connected to pressurized equipment or coiled tubing, facilitating subsequent high-density workover fluid flushing and well control to completely achieve blowout control. The wellhead reconstruction tool 100 is suitable when the second flange 200 or the blowout preventer 210 is intact. In cases where the distance between the second flange 200 and the blowout preventer 210 is small, such as less than 50mm, or when the outer side of the second flange 200 is equipped with a set screw or grease injection port, remote control can be used with automated handling tools and automated robotic arms to quickly complete the wellhead reconstruction operation, improving safety.

[0049] For example, the sealing pressure resistance of the wellhead reconstruction tool 100 is 35 MPa to 70 MPa. The maximum bore of the wellhead reconstruction tool 100 is 140 mm. The maximum temperature that the wellhead reconstruction tool 100 can withstand is 350 degrees Celsius.

[0050] In some examples, such as Figures 1 to 3 As shown, the tool body 110 includes: a hydraulic cylinder 111; a hydraulic cylinder cover 112, which is disposed inside the hydraulic cylinder 111 and sleeved on the piston 140; wherein, a boss is provided at one end of the piston 140 away from the first flange 120, and an annular space 113 is formed between the top of the hydraulic cylinder cover 112 and the boss; one of the piston 140, the hydraulic cylinder 111 and the hydraulic cylinder cover 112 is provided with a hydraulic oil passage 114 along the axial direction, and the hydraulic oil passage 114 is connected to the annular space 113.

[0051] It is understood that the tool body 110 may be equipped with a hydraulic cylinder 111 and a hydraulic cylinder cover 112. The hydraulic cylinder 111 has the aforementioned cavity formed inside, and the hydraulic cylinder cover 112 is disposed within the cavity and fitted onto the piston 140. The hydraulic cylinder cover 112 protects the hydraulic cylinder 111 and prevents external debris from entering the hydraulic cylinder 111, keeping the hydraulic cylinder 111 clean and extending its service life. The dimension of the end of the piston 140 facing the second flange 200 is adapted to the dimension of the second flange 200 to ensure reliable sealing connection with the second flange 200. For example, the diameter of the end of the piston 140 facing the second flange 200 is larger than the diameter of the end of the piston 140 facing the first flange 120, and a boss is provided on the back side of the end of the piston 140 facing the second flange 200. After the piston 140 and hydraulic cylinder head 112 are assembled, an annular space 113 is formed between the hydraulic cylinder head 112 and the top of the boss. A hydraulic oil passage 114 is provided along the axial direction in one of the piston 140, hydraulic cylinder 111, or hydraulic cylinder head 112, and the hydraulic oil passage 114 connects to the annular space 113. An external hydraulic source delivers hydraulic oil to the hydraulic oil passage 114, and then to the annular space 113, to push the piston 140 towards the second flange 200. After the hydraulic oil is removed from the annular space 113 and the hydraulic oil passage 114, the piston 140 moves away from the second flange 200. The piston 140 is reliably driven by hydraulic pressure.

[0052] For example, the hydraulic oil passage 114 is opened along the axial direction of the piston 140, and an injection hole is opened radially on the first flange 120, which is connected to the hydraulic oil passage 114. Hydraulic oil from the hydraulic source can be delivered to the hydraulic oil passage 114 through the injection hole via a hydraulic injection line.

[0053] In some examples, such as Figures 1 to 3 As shown, it also includes: a first sealing ring 150, disposed between the inner side wall of the hydraulic cylinder cover 112 and the side wall of the piston 140, the first sealing ring 150 being located above the annulus 113; and a second sealing ring 160, disposed in the second annulus 140, the side wall of the piston 140 having a second groove, the second sealing ring 160 being located below the annulus 113.

[0054] Understandably, the wellhead reconstruction tool 100 may also be equipped with a first sealing ring 150 and a second sealing ring 160. Specifically, a first annular groove is formed above the annulus 113 on the inner wall of the hydraulic cylinder cover 112; a second annular groove is formed below the annulus 113. The first sealing ring 150 is disposed in the first annular groove, sealing the portion of the hydraulic cylinder and piston 140 above the annulus 113; the second sealing ring 160 seals the portion of the hydraulic cylinder and piston 140 below the annulus 113, preventing hydraulic oil leakage in the annulus 113 and improving reliability.

[0055] For example, multiple first sealing rings 150 and second sealing rings 160 can be provided and arranged at intervals along the axial direction of the hydraulic cylinder cover 112 to improve the sealing effect.

[0056] In some examples, such as Figures 1 to 3 As shown, it also includes a sealing assembly 170, which is used to cooperate with the piston 140 to seal the second flange 200.

[0057] Understandably, the wellhead reconstruction tool 100 may also be equipped with a sealing component 170, which, in conjunction with the piston 140, achieves a seal on the second flange 200, ensuring a sealing effect.

[0058] In some examples, such as Figures 1 to 3 As shown, the sealing assembly 170 includes: a third sealing ring 171 disposed at one end of the piston 140 away from the first flange 120, wherein when the piston 140 and the second flange 200 are in contact, the third sealing ring 171 is inserted into the third groove of the second flange 200; and a fourth sealing ring 172 disposed at one end of the piston 140 away from the first flange 120, located inside the third sealing ring 171 along the radial direction of the piston 140, wherein when the piston 140 and the second flange 200 are in contact, the fourth sealing ring 172 is compressed and deformed and adheres tightly to the piston 140 and the second flange 200.

[0059] Understandably, the sealing assembly 170 may be provided with a third sealing ring 171 and a fourth sealing ring 172. The third sealing ring 171 is located at the end of the piston 140 facing the second flange 200, and may be a sealing steel ring. A third groove, a steel ring groove, is formed at the top of the second flange 200. When the piston 140 moves closer to the second flange 200, the sealing steel ring inserts into the groove. When the piston 140 and the second flange 200 are in contact, the sealing steel ring and the groove work together to create a seal, ensuring a good sealing effect. The fourth sealing ring 172 is also located at the end of the piston 140 facing the second flange 200, and is positioned radially from the piston 140, inside the third sealing ring 171. As the piston 140 moves closer to the second flange 200, the fourth sealing ring 172, after abutting against the top of the second flange 200, is subjected to pressure from the piston 140. The fourth sealing ring 172 compresses and deforms to tightly adhere to the second flange 200 and the piston 140, further improving the sealing effect. The hydraulically driven piston 140, in conjunction with the sealing assembly 170, achieves a sealed connection between the piston 140 and the second flange 200, eliminating the need for bolts, improving connection efficiency, and allowing for easy connection operations even with a remotely controlled robotic arm.

[0060] For example, the third sealing ring 171 can be a polytetrafluoroethylene (PTFE) composite sealing ring, which can be molded from suspension polymerized PTFE resin. It has excellent chemical corrosion resistance, is suitable for the working environment of oil fields, ensures the reliability of the third sealing ring 171, and makes the third sealing ring 171 have a long service life.

[0061] In some examples, such as Figure 1 and Figure 3 As shown, the connecting part 130 includes: a hook 131, one end of the hydraulic cylinder 111 facing away from the first flange 120 is used to be sleeved on the second flange 200, the hook 131 is connected to the inner side wall of the end of the hydraulic cylinder 111 facing away from the first flange 120 through an elastic member 132, and the end of the hook 131 facing the first flange 120 is provided with a hook groove 1311; wherein, when the second flange 200 is engaged with the hook groove 1311, the elastic member 132 is in a compressed state.

[0062] Understandably, the connecting part 130 may be provided with a hook 131 and an elastic element 132. The end of the hydraulic cylinder 111 facing the second flange 200 is larger, so that this end can be fitted onto the second flange 200. The hook 131 is connected to the inner wall of the end of the hydraulic cylinder 111 facing the second flange 200 via the elastic element 132. Furthermore, the hook 131 has a vertically oriented groove 1311 facing the first flange 120. With this configuration, during the installation of the wellhead reconstruction tool 100 onto the second flange 200, the hook 131 is subjected to pressure from the outer wall of the second flange 200, and the elastic element 132 is compressed, causing the hook 131 to move towards the inner wall of the end of the hydraulic cylinder 111 facing the second flange 200, thereby increasing the distance between the hook 131 and the outer wall of the second flange 200 until the hook 131 and the outer wall of the second flange 200 are in contact. The hook 131 can continue to move downwards until the hook groove 1311 of the hook 131 moves to the second flange 200, and the elastic element 132 rebounds, driving the hook 131 to move towards the outer side of the second flange 200, so that the second flange 200 is engaged with the hook groove 1311. Under the action of the rebound force of the elastic element 132, the hook 131 clamps the second flange 200, thereby achieving a fixed connection between the hydraulic cylinder 111 and the second flange 200.

[0063] In some examples, such as Figure 1 and Figure 3 As shown, the inner side of the hook 131 opposite to the first flange 120 is provided with a chamfer.

[0064] Understandably, the inner side of the end of the hook 131 away from the first flange 120 is chamfered. The chamfer guides the hook 131 to move against the outer wall of the second flange 200, ensuring smooth movement.

[0065] In some examples, such as Figure 2 As shown, the connecting part 130 includes a plurality of retrieval spears 133 disposed at one end of the piston 140 away from the first flange 120. The plurality of retrieval spears 133 are used to correspond to a plurality of threaded holes of the second flange 200. When the piston 140 is in contact with the second flange 200, the retrieval spears 133 are inserted into the threaded holes and engaged with the inner sidewall of the threaded holes. When the piston 140 moves away from the second flange 200, the retrieval spears 133 are withdrawn from the threaded holes.

[0066] Understandably, the connecting part 130 can be equipped with multiple retrieval spears 133, which can be hydraulically retractable. The positions of the retrieval spears 133 correspond to the positions of the threaded holes on the second flange 200, and the number of retrieval spears 133 is the same as the number of threaded holes. With this configuration, during the installation of the wellhead reconstruction tool 100 onto the second flange 200, the piston 140 moves downwards, causing the retrieval spears 133 to be inserted into the threaded holes. The retrieval spears 133 can also engage with the inner wall of the threaded holes to fix the wellhead reconstruction tool 100 to the second flange 200. Using multiple retrieval spears 133 ensures force balance while improving connection force and stability. When it is necessary to remove the wellhead reconstruction tool 100 from the second flange 200, the piston 140 moves away from the second flange 200, and the retrieval spears 133 retract from the threaded holes. By setting the retrieval spear 133 for connection, the radial dimension of the hydraulic cylinder 111 can be shortened, requiring only the piston 140 dimension to correspond to the second flange 200 dimension, thereby improving the applicability of the wellhead reconstruction tool 100, for example, for situations where the distance between the second flange 200 and the blowout preventer 210 is smaller, such as less than 30 mm.

[0067] like Figure 3 As shown, a wellhead reconstruction system is proposed according to a second aspect of this disclosure, comprising: a wellhead reconstruction tool 100 as described in any of the above technical solutions, wherein the tool body 110 of the wellhead reconstruction tool 100 includes: a hydraulic cylinder 111; a hydraulic cylinder cover 112 disposed within the hydraulic cylinder 111 and sleeved on the piston 140; wherein a boss is provided at one end of the piston 140 away from the first flange 120, and an annular space 113 is formed between the top of the hydraulic cylinder cover 112 and the boss; and a hydraulic oil passage 114 is provided along the axial direction for one of the piston 140, the hydraulic cylinder 111, and the hydraulic cylinder cover 112. The hydraulic circuit 114 is connected to the annulus 113; the drive unit is used to transport the wellhead reconstruction tool 100 to the wellhead; the manipulator is used to install the wellhead reconstruction tool 100 onto the second flange 200; the blowout preventer 210 is connected to the first flange 120 before the drive unit transports the wellhead reconstruction tool 100; the hydraulic injection line has an injection hole on the first flange 120, which is connected to the hydraulic circuit 114, and hydraulic oil from the hydraulic source is delivered to the hydraulic circuit 114 through the hydraulic injection line; wherein, the drive unit and the manipulator are both remotely controlled.

[0068] Understandably, the wellhead reconstruction system may include a wellhead reconstruction tool 100, a drive unit, a robotic arm, a blowout preventer 210, and a hydraulic injection line. The wellhead reconstruction system possesses all the beneficial effects of the aforementioned wellhead reconstruction tool 100, which will not be elaborated upon here. One of the piston 140, hydraulic cylinder 111, and hydraulic cylinder head 112 of the wellhead reconstruction tool 100 has a hydraulic passage 114 along its axial direction. An injection port is radially formed on the first flange 120, connecting to the hydraulic passage 114. Hydraulic oil from a hydraulic source is delivered to the hydraulic passage 114 via the hydraulic injection line. During the installation of the wellhead reconstruction tool 100, the blowout preventer 210 can be pre-installed on the first flange 120. The combination of the blowout preventer 210 and the first flange 120 is placed on the drive unit. One end of the hydraulic injection line is connected to the hydraulic station, and the other end is connected to the injection port. The remotely controlled drive unit moves towards the wellhead. Upon reaching the designated position, the combination of the blowout preventer 210 and the first flange 120 is removed from the drive unit by a manipulator. With the connecting part 130 being a hook 131, the hydraulic cylinder 111 is connected to the second flange 200 via the hook 131. The control hydraulic station begins supplying hydraulic oil, which is delivered to the annulus 113 via the hydraulic injection line, injection port, and hydraulic oil passage 114. This drives the piston 140 to move closer to the second flange 200, so that the piston 140 fits against the top of the second flange 200. The sealing assembly 170 then seals the piston 140 to the second flange 200. By closing the full-sealing gate of the blowout preventer 210, the passages of the piston 140, the first flange 120, and the second flange 200 are sealed, achieving rapid blowout prevention. After the blowout is controlled, it can be directly connected to pressurized equipment or coiled tubing, facilitating subsequent high-density workover fluid flushing and well control to completely eliminate the blowout. With the connecting part 130 being a retrieval spear 133, the robotic arm operates the hydraulic cylinder 111 to align with the second flange 200, then controls the hydraulic station to begin supplying hydraulic oil. The hydraulic oil is delivered to the annulus 113 via the hydraulic injection line, injection hole, and hydraulic oil circuit 114, driving the piston 140 to move closer to the second flange 200, allowing the retrieval spear 133 to be inserted and engaged in the threaded hole of the second flange 200, thus completing the fixation of the hydraulic cylinder 111 and the second flange 200, and the sealing connection between the piston 140 and the second flange 200. Considering the increasing number of potential wells in the later stages of oilfield development, and the average number of blowouts occurring 3 to 5 per year during oil and water well workover operations with intact flanges, the wellhead reconstruction system proposed in this application can significantly reduce the labor intensity, personal risk level, and environmental pollution of well control and rescue personnel.

[0069] In some examples, the length of the aforementioned hydraulic injection pipeline is greater than 25m.

[0070] Understandably, considering the safety distance in the event of a blowout, the length of the hydraulic injection pipeline can be greater than 25m to avoid the blowout affecting the hydraulic station and the personnel near the hydraulic station, thereby improving safety.

[0071] In this disclosure, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise expressly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0072] In the description of this disclosure, it should be understood that the terms "upper," "lower," "left," "right," "front," "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure.

[0073] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0074] The above are merely preferred embodiments of this disclosure and are not intended to limit this disclosure. Various modifications and variations can be made to this disclosure by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A wellhead reconstruction tool, characterized in that, include: The tool body has a cavity formed inside it; A first flange is connected to the top of the tool body, and the first flange is used to connect to the blowout preventer; A connecting part, wherein the bottom of the tool body is used to connect to the second flange of the oil well via the connecting part; A piston is disposed within the cavity, and a channel is formed inside the piston. The piston is used to move toward or away from the second flange, wherein a sealing connection is formed between the tool body and the second flange when the piston moves to fit against the second flange.

2. The wellhead reconstruction tool according to claim 1, characterized in that, The main body of the tool includes: Hydraulic cylinder; A hydraulic cylinder cover is disposed inside the hydraulic cylinder and sleeved on the piston; The piston has a boss at the end opposite to the first flange, and an annular space is formed between the top of the hydraulic cylinder cover and the boss. One of the piston, the hydraulic cylinder, and the hydraulic cylinder cover has a hydraulic oil passage along the axial direction, and the hydraulic oil passage is connected to the annular space.

3. The wellhead reconstruction tool according to claim 2, characterized in that, Also includes: The first sealing ring is disposed in the first sealing ring groove on the side wall of the piston and is located above the annular space. The second sealing ring is disposed in the second sealing ring groove provided on the side wall of the piston, and the second sealing ring is located below the annular space.

4. The wellhead reconstruction tool according to claim 3, characterized in that, Also includes: A sealing assembly is used to cooperate with the piston to seal the second flange.

5. The wellhead reconstruction tool according to claim 4, characterized in that, The sealing assembly includes: The third sealing ring is disposed at the end of the piston away from the first flange. When the piston and the second flange are in contact, the third sealing ring is inserted into the third groove of the second flange. The fourth sealing ring is disposed at the end of the piston away from the first flange. Along the radial direction of the piston, the fourth sealing ring is located inside the third sealing ring. When the piston and the second flange are in contact, the fourth sealing ring is compressed and deformed and adheres tightly to the piston and the second flange.

6. The wellhead reconstruction tool according to claim 2, characterized in that, The connecting part includes: The hook claw is used to fit the end of the hydraulic cylinder away from the first flange onto the second flange. The hook claw is connected to the inner wall of the end of the hydraulic cylinder away from the first flange by an elastic element. The end of the hook claw facing the first flange is provided with a hook groove. When the second flange is engaged with the groove, the elastic element is in a compressed state.

7. The wellhead reconstruction tool according to claim 6, characterized in that, The inner side of the end of the hook opposite to the first flange is chamfered.

8. The wellhead reconstruction tool according to claim 2, characterized in that, The connecting part includes: Multiple retrieval spears are disposed at the end of the piston opposite to the first flange, and the multiple retrieval spears are used to correspond to multiple threaded holes of the second flange; Specifically, when the piston is in contact with the second flange, the spear is inserted into the threaded hole and engaged with the inner wall of the threaded hole; when the piston moves away from the second flange, the spear retracts from the threaded hole.

9. A wellhead reconstruction system, characterized in that, include: The wellhead reconstruction tool according to any one of claims 1 to 8, wherein the tool body of the wellhead reconstruction tool comprises: a hydraulic cylinder; a hydraulic cylinder cover disposed inside the hydraulic cylinder and sleeved on the piston; wherein a boss is provided at one end of the piston away from the first flange, an annular space is formed between the top of the hydraulic cylinder cover and the boss, and a hydraulic oil passage is provided along the axial direction for one of the piston, the hydraulic cylinder and the hydraulic cylinder cover, the hydraulic oil passage being connected to the annular space; A drive unit is used to transport the wellhead reconstruction tool to the wellhead. A robotic arm is used to install the wellhead reconstruction tool onto the second flange; Blowout preventer, connected to the first flange before the drive unit transports the wellhead reconstruction tool; A hydraulic injection pipeline is provided, wherein the first flange is provided with an injection hole, the injection hole is connected to the hydraulic oil circuit, and hydraulic oil from the hydraulic source is delivered to the hydraulic oil circuit through the hydraulic injection pipeline; Both the drive device and the robotic arm are remotely controlled.

10. The wellhead reconstruction system according to claim 9, characterized in that, The length of the hydraulic injection pipeline is greater than 25m.

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