Salvage device for coiled tubing

Abstract

The utility model provides a fishing device for a coiled tubing, which comprises an outer cylinder, an upper joint, a return spring and a pin hole for fixing the outer cylinder and the upper joint, wherein a key slot, a key block and an O-shaped sealing ring are arranged on the contact wall of the outer cylinder and the upper joint; the bottom of the upper connector is connected with a connecting cylinder, the lower end of the connecting cylinder is provided with an extension C-ring-shaped push block, a second spring between the push block and the upper connector and a pawl in threaded connection with the push block, and the inner side of the lower end of the pawl is provided with pawl teeth; the inner wall of the lower end of the outer cylinder is of an inverted circular truncated cone structure. When the fishing device is used for fishing a fish, under the combined action of the pawl, the second spring and the outer cylinder, the pawl can realize variable-diameter grabbing, the fish head fishing neck is grabbed through variable-diameter grabbing of the pawl or the fish head is anchored through pawl teeth, and the fish smoothly enters the fishing device to realize fish entering; when the fishing tool is used for fishing fishes without variable diameters, the fishes can be clamped through the pawl teeth, the fishes with the fishing necks can be fished through the variable-diameter positions of the pawls, fishing of fish heads of various sizes or shapes is achieved, and the fishing success rate is increased.

Description

Technical Field

[0001] The utility model relates to the technical field of tubing fishing tools, and particularly relates to a continuous tubing fishing device. Background Art

[0002] Continuous tubing fishing tools play an important role in oil and gas exploitation. They are mainly used to solve problems such as downhole blockage, stuck pipe, and fishing failure wells. With the advantages of simple operation, high flexibility, low cost, and resistance to high pressure and corrosion, they are widely used in complex environments such as deepwater oil and gas fields. However, there are still some problems in the existing technology, such as: no circulation channel or only a one-way circulation channel, and in extreme cases, it is impossible to effectively flush and clean the fish top and the wellbore above the fish top, increasing the risk of fishing operations and reducing the fishing success rate; the gripper has a single size or a small moving range, and cannot fish fish heads of various sizes or shapes, resulting in a low fishing success rate; the end of the fishing tool is blunt, which is not convenient for entering the fish, reducing the fishing success rate. Summary of the Utility Model

[0003] In order to solve the technical problem of the low fishing success rate of the existing fishing tools, the utility model provides a continuous tubing fishing device, which improves the fishing success rate.

[0004] The specific solution provided by the utility model is as follows:

[0005] A continuous tubing fishing device includes: an outer cylinder and an upper joint, and the bottom of the upper joint is inserted into the top of the outer cylinder;

[0006] A circular protrusion is circumferentially provided in the middle of the upper joint. A compression state return spring is provided between the protrusion and the top end of the outer cylinder. A pin hole is provided on the outer wall of the lower end of the upper joint, and a corresponding pin hole is also provided at the corresponding position of the outer cylinder. A shear pin passes through the pin hole on the outer cylinder to fix the outer cylinder and the upper joint; above the shear pin, corresponding key grooves are provided on the outer cylinder and the upper joint, and a key block is slidably provided in the key grooves. Below the shear pin, an O-ring is provided in the gap between the outer cylinder and the upper joint;

[0007] The bottom of the upper joint is threadedly connected with a connecting cylinder. An outer extension is circumferentially provided at the lower end of the connecting cylinder. A C-shaped push block is provided above the outer extension. The push block is slidably embedded in the gap between the connecting cylinder and the outer cylinder. A natural state second spring is provided between the top end of the push block and the bottom end of the upper joint. The upper end of the pawl passes through the gap between the outer extension and the outer cylinder and is threadedly connected with the push block; the inner side of the lower end of the pawl is provided with pawl teeth; the inner wall of the lower end of the outer cylinder is in an inverted frustum structure, and the pawl is in close contact with the inner wall;

[0008] A guide shoe is provided at the bottom end of the outer cylinder.

[0009] Preferably, the upper sub is of a through-hole structure, and threads are provided on the inner side of the upper end.

[0010] Preferably, the inside of the fishing device is of a through-hole structure.

[0011] Preferably, at least three such pawls are provided inside the fishing device.

[0012] Preferably, at least three such key grooves and corresponding key blocks (5) are provided along the circumferential direction of the upper sub.

[0013] Preferably, the bottom end of the pawl is wedge-shaped, and the side away from the inner wall of the outer cylinder is an inclined surface.

[0014] Beneficial effects:

[0015] The utility model provides a fishing device for continuous oil pipes, which comprises an outer cylinder, and an upper sub is inserted at the upper end of the outer cylinder; a circle of protrusions is provided along the circumferential direction in the middle of the upper sub, a reset spring in a compressed state is provided between the protrusions and the top end of the outer cylinder, pin holes are provided along the circumferential direction at the lower end of the upper sub, and pin holes are also provided at the corresponding positions of the outer cylinder, and a shear pin passes through the pin holes on the outer cylinder to fix the outer cylinder and the upper sub; above the shear pin, on the contact wall between the outer cylinder and the upper sub, key grooves are provided at corresponding positions along the vertical direction, and key blocks are slidably arranged in the key grooves, and an O-ring is provided in the gap between the outer cylinder and the upper sub below the shear pin; a connecting cylinder is threadedly connected to the bottom of the upper sub, an outer extension is provided along the circumferential direction at the lower end of the connecting cylinder, a C-shaped push block is provided above the outer extension, the push block is slidably embedded in the gap between the connecting cylinder and the outer cylinder, a second spring in a natural state is provided between the top end of the push block and the bottom end of the upper sub, the upper end of the pawl passes through the gap between the outer extension and the outer cylinder and is threadedly connected to the push block; a pawl tooth is provided on the inner side of the lower end of the pawl; the inner wall of the lower end of the outer cylinder is of an inverted frustum structure, and the pawl is in close contact with the inner wall; a guide shoe is provided at the bottom end of the outer cylinder.

[0016] When using the above device to fish for the sunken fish, push the fishing device downward. Under the action of the sunken fish, the pawl moves upward and compresses the second spring through the push block. Since the inner wall at the lower end of the outer cylinder has an inverted frustum structure with an increasing upward diameter, the grasping size of the pawl becomes larger, allowing the sunken fish to smoothly enter the fishing device. When pulling the fishing device upward, the second spring rebounds, and the fish head is grasped through the variable diameter of the pawl or the fish head is anchored through the pawl teeth, achieving fish entry and improving the fishing success rate. Through the combined interaction of the second spring, the pawl, and the outer cylinder, when fishing for a sunken fish without variable diameter, the sunken fish can be caught by the pawl teeth, and for a sunken fish with a fishing neck, it can be fished through the variable diameter of the pawl. Fish heads of various sizes or shapes can be fished, achieving the fishing effect and improving the fishing success rate. A guide shoe is provided at the bottom end of the outer cylinder, which can guide the fish by rotating the fishing device, making it more convenient for the fish to enter and improving the fishing success rate. A keyway and a key block are provided to transmit torque, ensuring that when the upper joint is rotated, the outer cylinder rotates simultaneously under the drive of the upper joint, preventing the upper joint from idling, thereby increasing the probability of fish entry and ensuring the success rate of fishing.

[0017] Particularly, if the maximum pulling tonnage during construction design is exceeded and the fish cannot be lifted after fishing, or the coiled tubing gets stuck during the pulling process and cannot be released by movement, the shear pin can be cut by increasing the pulling tonnage to the shear tonnage of the shear pin. Utilizing the reset function of the reset spring, the outer cylinder is pushed downward to move to a position with a larger inner wall diameter, opening the pawl and canceling the anchoring effect on the sunken fish to achieve releasing the tool and avoid causing secondary accidents.

[0018] Particularly, the fishing device has a through-hole structure. By pumping through the coiled tubing, the fish head can be flushed. In extreme cases, two-way cyclic flushing can be achieved, improving the fish entry efficiency and thus ensuring the success rate of the fishing operation.

[0019] Particularly, the bottom end of the pawl is wedge-shaped, and the side away from the inner wall of the outer cylinder is an inclined surface, which can reduce resistance during the fish entry process, greatly improving the success rate of fish entry and ensuring the success of the fishing operation. Description of the Drawings

[0020] Figure 1 It is a schematic structural diagram of a fishing device for coiled tubing provided by the present utility model.

[0021] In the figure: 1 - outer cylinder; 2 - guide shoe; 3 - upper joint; 4 - reset spring; 5 - key block; 6 - shear pin; 7 - O-ring seal; 8 - spring; 9 - push block; 10 - pawl; 11 - pawl teeth; 12 - connecting cylinder. Detailed Embodiments

[0022] The following further describes the present utility model in conjunction with the drawings and embodiments.

[0023] Figure 1This is a schematic structural diagram of a fishing device for continuous tubing provided by this application. As Figure 1 shown, a fishing device for continuous tubing includes an outer cylinder 1, and an upper joint 3 is inserted into the upper end of the outer cylinder 1;

[0024] A circle of protrusions is provided in the middle of the upper joint 3 along the circumferential direction. A reset spring 4 in a compressed state is provided between the protrusions and the top end of the outer cylinder 1. Pin holes are provided along the circumferential direction at the lower end of the upper joint 3, and corresponding positions of the outer cylinder 1 are also provided with pin holes. A shear pin 6 passes through the pin holes on the outer cylinder 1 to fix the outer cylinder 1 and the upper joint 3; above the shear pin 6, on the contact surface between the outer cylinder 1 and the upper joint 3, key grooves are provided at corresponding positions along the vertical direction, and key blocks 5 are slidably arranged in the key grooves. An O-ring 7 is provided in the gap between the outer cylinder 1 and the upper joint 3 below the shear pin 6;

[0025] The bottom of the upper joint 3 is threadedly connected with a connecting cylinder 12. An outer extension is provided along the circumferential direction at the lower end of the connecting cylinder 12. A C-shaped push block 9 is provided above the outer extension. The push block 9 is slidably embedded in the gap between the connecting cylinder and the outer cylinder 1. A second spring 8 in a natural state is provided between the top end of the push block 9 and the bottom end of the upper joint 3. The upper end of the pawl 10 passes through the gap between the outer extension and the outer cylinder 1 and is threadedly connected with the push block 9; Pawl teeth 11 are provided on the inner side of the lower end of the pawl 10; the inner wall of the lower end of the outer cylinder 1 is in an inverted frustum structure, and the pawl 10 is in close contact with the inner wall; A guide shoe 2 is provided at the bottom end of the outer cylinder 1.

[0026] When using the device provided by this application to fish for the fish left in the well, push the fishing device downward. Under the action of the fish left in the well, the pawl moves upward and compresses the second spring through the push block. Since the inner wall of the lower end of the outer cylinder is in an inverted frustum structure and the diameter gradually becomes larger upward, the grasping size of the pawl can become larger, and the fish left in the well can smoothly enter the fishing device; when pulling the fishing device upward, the second spring rebounds, and the fish head is grasped through the variable diameter of the pawl or the fish head is anchored through the pawl teeth, realizing fish entry, and improving the fishing success rate. Through the combined interaction of the second spring, the pawl and the outer cylinder, when fishing for a fish left in the well without variable diameter, the fish left in the well can be stuck by the pawl teeth, and for a fish left in the well with a fishing neck, the fish can be fished through the variable diameter part of the pawl. Fish heads of various sizes or shapes can be fished, achieving the fishing effect and improving the fishing success rate. A guide shoe is provided at the bottom end of the outer cylinder, and the fish can be guided by rotating the fishing device, making it more convenient for the fish to enter, and improving the fishing success rate.

[0027] Specifically, the upper joint 3 is a through-hole structure, and internal threads are provided on the inner side of the upper end.

[0028] Specifically, the inside of the fishing device is a through-hole structure.

[0029] In some embodiments, internal threads are provided on the upper end inside of the upper sub 3, and it is threadedly connected to the coiled tubing through the threads. The coiled tubing is lowered to the position of the fish, and the fish fishing operation is carried out; the upper sub 3 is a through-hole structure, which is connected to the connecting cylinder 12 to make the whole fishing device a through-hole structure. Before the fishing operation, the fish head can be flushed by pumping through the coiled tubing; in extreme cases, if there is a blockage between the fishing tool and the fish, the fish can be flushed through the casing to achieve two-way circulating flushing, thereby ensuring the success rate of the coiled tubing fishing operation.

[0030] Specifically, at least three of the ratchet claws 10 are provided inside the fishing device.

[0031] In some embodiments, the number of ratchet claws can be set according to the size of the fishing tool or the size of the fish. In this embodiment, a fishing tool with 6 ratchet claws is provided, and a certain gap is reserved between the ratchet claws to ensure sufficient movement space when grasping the fish.

[0032] Specifically, at least three key grooves and the corresponding key blocks 5 are provided along the circumferential direction of the upper sub 3.

[0033] In some embodiments, the key grooves and key blocks are provided to transmit the torque between the upper sub and the outer cylinder, ensuring that when the upper sub rotates, the outer cylinder rotates simultaneously under the drive of the upper sub, preventing the upper sub from idling, thereby increasing the probability of entering the fish and ensuring the success rate of fishing; in this embodiment, a fishing tool with 3 key grooves and key blocks is provided, which can ensure the working intensity of rotation and enable the outer cylinder to slide smoothly downward when releasing the grip.

[0034] Specifically, the bottom end of the ratchet claw 10 is wedge-shaped, and the side away from the inner wall of the outer cylinder 1 is an inclined surface.

[0035] In some embodiments, the bottom end of the ratchet claw 10 is wedge-shaped, and the side away from the inner wall of the outer cylinder 1 is an inclined surface. During the process of entering the fish, the wedge shape can reduce the resistance, greatly increasing the success rate of entering the fish and ensuring the success of the fishing operation.

[0036] For a fishing device for coiled tubing provided by the present application, during operation, it is threadedly connected to the end of the coiled tubing through the upper sub 3, the coiled tubing is lowered to a predetermined depth, the situation of the fish head is explored, then the fish head is flushed by pumping through the tubing, and after completion, the downhole falling objects are lowered for fishing. After successful capture, the coiled tubing is lifted. The specific working process is as follows:

[0037] Fishing process:

[0038] (1) When the coiled tubing is lowered to the position of the fish, the fish head can be flushed by pumping through the coiled tubing to remove impurities such as residual sand, water scale, and rubber debris on the wellbore or the fish head. These impurities may affect the normal operation and fishing effect of the fishing tool, thereby ensuring the success rate of the coiled tubing fishing operation;

[0039] (2) Lower the coiled tubing to the position of the fish, and assist the downhole fish to enter the fish through the guide shoe 2, guiding the top of the fish to smoothly enter the fishing barrel device;

[0040] (3) Lower the coiled tubing to the position of the fish. When the top of the fish pushes the pawl 11, the spring 8 is compressed by pushing the push block 9. After the fish entry is completed, the spring 9 rebounds, and the variable diameter on the pawl 10 catches the fishing neck of the fish head or anchors the fish head through the pawl teeth 11 to achieve fish entry;

[0041] (4) Lift the coiled tubing to complete the fishing of the dropped object.

[0042] Releasing process:

[0043] If the lifting exceeds the maximum lifting tonnage designed for the construction and the object cannot be lifted off after fishing, or the coiled tubing is stuck during the lifting process and cannot be released by activities, the shear pin 6 can be cut by increasing the lifting tonnage to the shear tonnage of the shear pin 7. Through the reset function of the reset spring 4, the outer cylinder is pushed downward. Relying on the inverted conical surface structure on the inner wall of the lowered outer cylinder, the pawl 10 and the pawl 11 are opened to cancel the anchoring effect on the fish, realizing the release.

[0044] It should be noted that the above specific embodiments can enable those skilled in the art to more comprehensively understand the present utility model creation, but do not limit the present utility model creation in any way. Therefore, although this specification has described the present utility model creation in detail with reference to the drawings and embodiments, those skilled in the art should understand that the present utility model creation can still be modified or equivalently replaced. In short, all technical solutions and their improvements that do not depart from the spirit and scope of the present utility model creation should be covered by the protection scope of the patent of the present utility model creation.

Claims

1. A fishing device for continuous tubing, characterized in that, It includes an outer cylinder (1) and an upper joint. The bottom of the upper joint is inserted into the top of the outer cylinder (1). A circular protrusion is provided circumferentially in the middle of the upper joint (3). A reset spring (4) in a compressed state is provided between the protrusion and the top end of the outer cylinder (1). A pin hole is provided on the outer wall of the lower end of the upper joint (3), and a corresponding pin hole is also provided on the outer cylinder (1). A shear pin (6) passes through the pin hole on the outer cylinder (1) to fix the outer cylinder (1) and the upper joint (3). Above the shear pin (6), corresponding key grooves are provided on the outer cylinder (1) and the upper joint (3), and a key block (5) is slidably arranged in the key grooves. Below the shear pin (6), an O-ring (7) is provided in the gap between the outer cylinder (1) and the upper joint (3). A connecting cylinder (12) is threadedly connected to the bottom of the upper joint (3). An outer extension is provided circumferentially at the lower end of the connecting cylinder (12). Above the outer extension, a C-shaped push block (9) is provided. The push block (9) is slidably embedded in the gap between the connecting cylinder and the outer cylinder (1). A second spring (8) in a natural state is provided between the top end of the push block (9) and the bottom end of the upper joint (3). The upper end of a ratchet pawl (10) passes through the gap between the outer extension and the outer cylinder (1) and is threadedly connected to the push block (9). Ratchet teeth (11) are provided on the inner side of the lower end of the ratchet pawl (10). The inner wall of the lower end of the outer cylinder (1) is of an inverted frustum structure, and the ratchet pawl (10) is in close contact with the inner wall. A guide shoe (2) is provided at the bottom end of the outer cylinder (1).

2. The fishing device for continuous oil pipes according to claim 1, characterized in that, The upper joint (3) has a through-hole structure, and internal threads are provided on the inner side of the upper end.

3. The fishing device for continuous oil pipes according to claim 1, characterized in that The inside of the fishing device has a through-hole structure.

4. The fishing device for continuous oil pipes according to claim 1, wherein, At least three of the ratchet pawls (10) are provided inside the fishing device.

5. The fishing device for continuous oil pipes according to claim 1, characterized in that, At least three of the key grooves and the corresponding key blocks (5) are provided circumferentially along the upper joint (3).

6. The fishing device for continuous oil pipes according to claim 1, wherein The bottom end of the ratchet pawl (10) is wedge-shaped, and the side away from the inner wall of the outer cylinder (1) is an inclined surface.

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