A hydraulically retractable salvage cylinder

Abstract

This utility model discloses a hydraulically retractable retrieval cylinder, comprising: an upper connector, a guide sleeve, a connecting cylinder, an elastic component, a slip, a piston rod, a piston, a plug, an adjusting shim, and several sealing rings. A flow guide hole is provided on the piston rod, positioned outside the piston's sealing ring when the elastic component is in its initial position; and inside the piston's sealing ring when the elastic component is in a compressed state. During fish retrieval, regardless of the fish's shape, upon retrieval, the flow guide hole is blocked, causing pressure buildup. This results in a significant increase in pump pressure, allowing for accurate determination of fish retrieval.

Description

Technical Field

[0001] This utility model belongs to the technical field of oil machinery coiled tubing retrieval tools, and relates to a hydraulic retractable retrieval cylinder. Background Technology

[0002] In oil drilling or other downhole operations, "fallen fish" typically refers to drill strings, casing, tubing, or other tools that have fallen and become stuck in the well. Retrieving fallen fish is an important downhole operation technique aimed at freeing them from obstruction and safely removing them from the well. Chinese utility model patent (202420656437X) discloses a hydraulically retractable retrieval cylinder capable of retrieving and releasing fallen fish at any time. However, its shortcomings are: when conducting on-site retrieval operations, the commonly used coiled tubing retrieval tools typically rely on repeatedly pressing down the coiled tubing several times to observe whether the pump pressure increases, or observing whether the weight indicator increases when pulling it up. However, due to the irregular shape of the fallen fish, sometimes the increase in pump pressure is not significant; if the fallen fish is light, the change in the weight indicator is also not obvious, making it impossible to accurately determine on-site whether the fallen fish has been retrieved. Summary of the Invention

[0003] The technical problem this invention aims to solve is to be able to clearly determine whether a fish has been caught by using pump pressure when retrieving it.

[0004] The technical solution of this utility model is: a hydraulically retractable retrieval cylinder, including an upper connector 1, a guide shoe cylinder 2 detachably connected to the upper connector 1, and a slip 5 located inside the guide shoe cylinder 2. A piston rod 6, a piston 7, and an elastic component 4 mounted on the piston rod 6 are installed inside the guide shoe cylinder 2. The piston rod 6 is provided with several guide holes 6-1 serving as fluid channels. As the piston 7 moves up and down, the guide holes 6-1 can be opened or blocked. The piston 7 and the slip 5 are connected as a whole by a connecting cylinder 3. A second sealing ring 11 is provided in the inner hole of the piston 7.

[0005] The guide hole 6-1 is provided on the piston rod 6, located outside the second sealing ring 11 of the piston 7 when the elastic member 4 is in the initial position; and inside the second sealing ring 11 of the piston 7 when the elastic member 4 is in the compressed state.

[0006] The beneficial effect of this invention is that by setting the flow guide hole, the pressure difference before and after the fish is caught is increased, which helps to more accurately determine whether the catch was successful. Attached Figure Description

[0007] Figure 1 This is a front view of a hydraulically retractable retrieval cylinder according to the present invention; In the diagram, the components are: 1. Upper connector; 2. Shoe guide tube; 3. Connecting tube; 4. Spring; 5. Slipper; 6. Piston rod; 7. Piston; 8. Plug; 9. Adjusting shim; 10. First sealing ring; 11. Second sealing ring; 12. Third sealing ring; 6-1 guide hole; and 6-2 inlet hole. Detailed Implementation

[0008] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0009] This utility model discloses a hydraulically retractable retrieval cylinder for retrieving fallen fish during oil drilling operations, such as... Figure 1 As shown, it includes: an upper connector 1, a shoe guide tube 2, a connecting tube 3, an elastic component 4, a slipper 5, a piston rod 6, a piston 7, a plug 8, an adjusting shim 9, a first sealing ring 10, a second sealing ring 11, and a third sealing ring 12. The upper connector 1 and the shoe guide tube 2 are threadedly connected, the piston rod 6 and the piston 7 are sealed together, the elastic component 4 is installed on the piston rod 6, the thickness of the adjusting shim 9 is used to adjust the initial position of the elastic component 4, the piston rod 6 is threadedly sealed to the upper connector 1, the plug 8 is threaded to the head of the piston rod 7, and the slipper 5 and the piston 7 are connected as one unit by the connecting tube 3, so that the slipper 5 and the piston 7 can move up and down together on the piston rod 6. A guide hole 6-1 and a liquid inlet hole 6-2 are provided on the piston rod 6. The liquid inlet hole 6-2 is located between the piston rod 6 and the piston 7. After liquid is introduced, the piston is pushed upward, thereby driving the slip 5 to move upward. The guide hole is positioned as follows: when preparing to catch the fish, the guide hole 6-1 is located outside the second sealing ring 11 of the piston 7. After the fish is caught, the piston 7 moves upward and the guide hole 6-1 is located inside the second sealing ring 11 of the piston 7.

[0010] The working process of this utility model is as follows: When retrieving a fallen fish, the upper connector 1 is connected to the matching continuous tubing, and the entire retrieval cylinder is lowered into the well. After it touches the fallen fish, the pump is turned on to circulate and flush the top of the fish. At this time, the liquid simultaneously passes through the straight channel and the guide hole, and the pump pressure remains constant. The retrieval cylinder continues to move downward and introduces the fallen fish through the guide shoe 2 until the slipper 5 touches the fallen fish. Regardless of the shape of the fallen fish, as the fish is retrieved, the retrieval cylinder continues to move downward, and the slipper 5 and piston 7 move upward simultaneously. The guide hole 6-1 will then be located inside the second sealing ring 11 of the piston 7 and begin to pressurize. At this time, the pump pressure will rise significantly, indicating that the fallen fish has been retrieved, and there is no need to repeatedly press down the continuous tubing to determine this. At this point, the retrieval cylinder can be pulled up to continue the fish retrieval operation.

Claims

1. A hydraulically retractable retrieval cylinder, comprising an upper connector (1), a guide shoe cylinder (2) detachably connected to the upper connector (1), and a locking device (5) located inside the guide shoe cylinder (2), characterized in that: The shoe boot (2) is equipped with a piston rod (6), a piston (7) and an elastic component (4) installed on the piston rod (6). The piston rod (6) is provided with several guide holes (6-1) as fluid channels. As the piston (7) moves up and down, the guide holes (6-1) can be opened or blocked.

2. The hydraulically retractable retrieval cylinder as described in claim 1, characterized in that: The piston (7) and the slip (5) are connected as one unit through the connecting cylinder (3).

3. The hydraulically retractable retrieval cylinder as described in claim 1, characterized in that: A second sealing ring (11) is provided in the inner hole of the piston (7).

4. The hydraulically retractable retrieval cylinder as described in claim 1, characterized in that: The guide hole (6-1) is located on the piston rod (6), outside the second sealing ring (11) of the piston (7) when the elastic member (4) is in the initial position; and inside the second sealing ring (11) of the piston (7) when the elastic member (4) is in the compressed state.

5. The hydraulically retractable retrieval cylinder as described in claim 4, characterized in that: The thickness of the adjusting pad (9) is used to control the initial position of the elastic component (4).

6. The hydraulically retractable retrieval cylinder as described in claim 4, characterized in that: The piston rod (6) is provided with a liquid inlet hole 6-2 for liquid inlet to drive the piston to move up and down.

7. The hydraulically retractable retrieval cylinder as described in claim 6, characterized in that: The piston rod (6) is sealed at both ends by the first sealing ring (10) and the third sealing ring (12).

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