A hydraulic spear-finding sealing structure

Abstract

This utility model discloses a hydraulic spear-catching sealing structure. An upper connector is connected to a body at its lower end. A sealing component and a sealing push ring are fitted onto the body. An external rack is fixed to the inner wall of the sealing push ring. A gear is installed at the mounting port of the body, meshing with the external rack. A central rod is inserted into the inner bore of the body. The inner bore of the central rod is a blind hole structure with a closed upper end. A communication port communicating with the inner bore is provided on the outer periphery of the upper end of the central rod. From top to bottom, a back cap, a rack piston, and a return spring are sequentially fitted onto the outer periphery of the central rod. The rack piston meshes with the gear. This utility model uses a rack and pinion structure to ensure that when the spear-catching sealing assembly is lowered into the fish or when it is lifted to retrieve the fish, the sealing component is in its original state, smaller than the inner diameter of the fish. When sealing is needed, the pump is turned on, and the liquid pressure and the rack and pinion structure open the sealing component, establishing a seal and external circulation. This enhances the stability of the seal and improves the success rate of retrieval.

Description

Technical Field

[0001] This utility model relates to a hydraulic spear-retrieval sealing structure, belonging to the technical field of oil and gas field extraction and retrieval equipment. Background Technology

[0002] Oil and gas salvage operations are an extremely complex process, typically using a retrieval spear. However, simply using a spear to retrieve a fallen fish cannot create a seal. If the annulus of the fallen fish is blocked by debris, it is impossible to flush the annulus using mud circulation. Current technology conventionally involves fixing a rubber sleeve to the outer circumference of the lower end of the spear shaft to create an internal seal and establish external circulation. This rubber sleeve is larger than the inner hole of the fallen fish, forming a seal through compression. However, the downhole environment is complex, and this structure makes it difficult for the spear to enter the fallen fish, and the rubber ring is prone to damage before it even enters the inner hole, leading to seal failure. Utility Model Content

[0003] The purpose of this invention is to provide a sealing structure for a hydraulic fishing spear. This structure, used in conjunction with a fishing spear to retrieve fallen fish, ensures that a stable high-pressure mud circulation is formed in the outer annulus during the fish retrieval operation.

[0004] The technical solution of this utility model is as follows: A hydraulic spear-catching sealing structure includes an upper connector, a body connected to the lower end of the upper connector, a sealing component and a sealing push ring sleeved on the outer periphery of the body from top to bottom, the sealing component is a downward opening structure, an external rack is fixed on the inner wall of the sealing push ring, an installation port is provided on the body, a gear is provided at the installation port, the gear meshes with the external rack, a central rod is installed in the upper section of the large hole of the inner hole of the body, the inner hole of the central rod is a blind hole structure with the upper end closed, a communication port communicating with the inner hole is provided on the outer periphery of the upper end of the central rod, a back cap, a rack piston and a return spring are movably sleeved on the outer periphery of the central rod from top to bottom, the two ends of the rack piston abut against the back cap and the return spring respectively, the rack piston meshes with the gear, and in the normal state, the rack piston blocks the communication port;

[0005] The sealing component includes a metal part with a U-shaped structure and a rubber part with an opening at the lower end, with the upper end of the rubber part fitting into the metal part;

[0006] The lower end of the sealing push ring is provided with an axial groove, and the protruding rib on the outer periphery of the upper end of the body is inserted into the axial groove.

[0007] In the aforementioned hydraulic spear-retrieving sealing structure, the lower end of the rubber component is an outwardly opening horn mechanism, and the upper end of the sealing push ring is a conical structure.

[0008] In the aforementioned hydraulic spear sealing structure, a step is provided at the bottom of the lower end of the central rod, one end of the return spring abuts against the step, and a back cap is threadedly connected to the outer circumference of the upper end of the central rod.

[0009] In the aforementioned hydraulic spear-catching sealing structure, the rack piston has a rack structure in the middle and smooth surfaces at both ends.

[0010] In the aforementioned hydraulic spear sealing structure, multiple external racks are arranged and fixed on the inner wall of the sealing push ring, and multiple mounting ports are arrayed on the body, with a gear at each mounting port.

[0011] In the aforementioned hydraulic spear-catching sealing structure, under normal conditions, the upper end of the sealing push ring is embedded into the end opening of the sealing component.

[0012] In the aforementioned hydraulic spear-catching sealing structure, the upper end face of the metal part abuts against the lower end face of the upper connector.

[0013] The beneficial effects of this utility model are as follows: Compared with the prior art, the sealing assembly of this utility model adopts a gear and rack structure, which ensures that when the fishing spear sealing assembly is lowered into the fish or when it is lifted to retrieve the fish, the sealing component is in its original state and smaller than the inner diameter of the fish. When sealing is required, the pump is turned on to pressurize the liquid and the action of the gear and rack structure to open the sealing component, establish a seal and external circulation.

[0014] When the retrieval spear and sealing assembly are placed inside the fallen fish, or when the obstructing debris in the outer annulus is flushed away by the circulating mud, the pump is shut off and pressurized. At this time, the rack piston is pushed upward by the return spring, the sealing push ring moves downward, and the rubber parts of the sealing component close and stop working, thereby increasing the service life of the sealing assembly and ensuring that it is easier to enter the inner hole of the fallen fish when using the retrieval spear to retrieve the fallen fish.

[0015] Driven by hydraulic pressure and a gear rack, the rubber sealing component expands outward and presses against the inner hole of the fish to form a seal. The internal flow channel of the water hole is opened, allowing for external mud circulation to flush out any stuck debris in the outer annulus of the fish. The expansion force on the sealing part increases with pressure within a certain range, making it less prone to leakage. Compared with the existing interference compression method for fishing spears, this invention enhances the stability of the seal and improves the success rate of fishing. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model when the pump is not turned on and pressurized;

[0017] Figure 2 This is a schematic diagram of the structure of this utility model after the pump is started and pressurized;

[0018] Figure 3 This is a schematic diagram of the structure of this utility model when used in conjunction with a reaming spear;

[0019] Figure 4 This is a three-dimensional structural diagram of the present invention;

[0020] Figure 5 A three-dimensional structural diagram of the central rod;

[0021] Figure 6 This is a schematic diagram of the gear mounting structure.

[0022] Reference numerals: 1-Upper connector, 2-Body, 3-Sealing component, 4-Sealing push ring, 5-External rack, 6-Gear, 7-Center rod, 8-Connecting port, 9-Rack piston, 10-Return spring, 11-Metal part, 12-Rubber part, 13-Axial groove, 14-Rib, 15-Back cap. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0024] An embodiment of this utility model: A hydraulic spear-retrieving sealing structure includes an upper connector 1, with a body 2 threadedly connected to the lower end of the upper connector 1. A sealing component 3 and a sealing push ring 4 are fitted around the outer periphery of the body 2 from top to bottom. The sealing component 3 has a downward-opening structure. An external rack 5 is fixed to the inner wall of the sealing push ring 4. An installation port is provided on the body 2, and a gear 6 is provided at the installation port. The gear 6 meshes with the external rack 5. A central rod 7 is installed in the upper section of the inner hole of the body 2. The inner hole of the central rod 7 is a blind hole structure with the upper end closed. Multiple connecting ports 8 communicating with the inner hole are provided on the outer periphery of the upper end of the central rod 7. A back cap 15, a rack piston 9, and a return spring 10 are sequentially movably fitted around the outer periphery of the central rod 7 from top to bottom. The two ends of the rack piston 9 abut against the back cap 15 and the return spring 10 respectively. The rack piston 9 meshes with the gear 6. Under normal conditions (when the pump is not pressurized), the rack piston 9 blocks the connecting ports 8.

[0025] The sealing component 3 includes a U-shaped metal part 11 and a rubber part 12 with an opening at the lower end. The upper end of the rubber part 12 is inserted into the metal part 11, and the upper end face of the metal part 11 abuts against the lower end face of the upper connector 1. This structure limits and fixes the sealing component 3.

[0026] The lower end of the sealing push ring 4 is provided with an axial groove 13, and the protruding rib 14 on the outer periphery of the upper end of the body 2 is inserted into the axial groove 13. This ensures that the sealing push ring 4 and the body 2 cannot rotate relative to each other, so that the external rack 5 and gear 6 in the inner hole of the sealing push ring 4 will always be in a meshing state.

[0027] The lower end of the rubber component 12 is a horn-shaped mechanism with an outward opening, and the upper end of the sealing push ring 4 is a conical structure. When the sealing push ring 4 moves upward, it can effectively open the rubber component 12 to achieve a seal.

[0028] The bottom of the center rod 7 is provided with a step, and one end of the return spring 10 abuts against the step. The outer circumference of the upper end of the center rod 7 is threaded with a back cap 15. During installation, after the return spring 10 and the rack piston 9 are put on the outer circumference of the center rod 7, the back cap 15 is screwed on, thereby limiting and fixing the return spring 10 and the rack piston 9. Installation and disassembly are relatively convenient.

[0029] The rack piston 9 has a rack structure in the middle and smooth surfaces at both ends. The rack part is used to cooperate with the gear 6, and the smooth surfaces at both ends form a seal with the inner wall of the body 2.

[0030] Multiple external racks 5 are arranged and fixed on the inner wall of the sealing push ring 4, and multiple mounting ports are arrayed on the body 2. Each mounting port is provided with a gear 6. By setting multiple gears 6 and multiple external racks 5, the stability of the entire structure is ensured.

[0031] Under normal conditions (when the pump is not pressurized), the upper end of the sealing push ring 4 is embedded into the end opening of the sealing component 3, ensuring that after pressurization, the sealing push ring 4 can move upward and extend into the interior of the sealing component 3, thereby opening the sealing component 3 and forming a sealing structure.

[0032] The upper end face of the metal part 11 abuts against the lower end face of the upper connector 1, and the upper connector 1 is used to limit and fix the sealing component 3, so as to prevent the sealing component 3 from sliding upward after being squeezed by the sealing push ring 4.

[0033] The hydraulic spear-catching sealing structure of this utility model is mainly composed of upper connector 1, body 2, sealing component 3, sealing push ring 4, rack piston 9, return spring 10, center rod 7, back cap 15, gear 6 and other components.

[0034] The specific parts fit and function are as follows:

[0035] Upper connector 1:

[0036] 1. The upper inner hole is provided with a connecting thread that matches the drill bit for connecting the drill bit;

[0037] 2. The lower part is threadedly connected to the body 2 to form a seal and transmit torque. At the same time, it can also press the sealing component 3 to fix the sealing component 3 to the body 2 and form a sealing surface.

[0038] Sealing component 3:

[0039] 1. The upper part is a metal part 11, and the lower part is a rubber part 12. When squeezed, the inner hole of the rubber part 12 opens to form a seal;

[0040] 2. The lower rubber part 12 contacts the sealing push ring 4, and the contact surface is a conical surface. When the sealing push ring 4 moves upward, it will squeeze the sealing component 3 outward, causing the rubber part 12 to open outward.

[0041] 3. During operation, the sealing component 3 is located in the inner hole of the fish. When the rubber component 12 is squeezed and opens outward, the sealing component 3 can form a seal with the inner hole of the fish.

[0042] Sealing ring 4:

[0043] 1. The upper conical surface of the sealing push ring 4 contacts the sealing component 3, and the fit and function have been described above;

[0044] 2. The inner hole of the sealing push ring 4 is clearance-fitted with the body 2, allowing it to slide axially on the body 2;

[0045] 3. An external rack 5 is fixed in the inner hole of the sealing push ring 4. The external rack 5 meshes with the gear 6. When the gear 6 rotates, it can drive the sealing push ring 4 to slide on the body 2.

[0046] 4. An axial groove 13 is opened on the lower end face of the sealing push ring 4. This axial groove 13 cooperates with the rib 14 of the body 2 to ensure that the sealing push ring 4 and the body 2 cannot rotate relative to each other, so that the outer rack 5 and the gear 6 in the inner hole of the sealing push ring 4 will always be in a meshing state.

[0047] Gear 6:

[0048] 1. Gear 6 is fitted onto the gear shaft. During installation, gear 6 is placed at the mounting port of body 2. The gear shaft is inserted through the through hole on one side of the mounting port, passes through gear 6, and extends into the through hole on the other side. Threaded plugs with gear shafts are then placed at the through holes on both sides to achieve fixed installation of gear 6.

[0049] 2. The bottom end of gear 6 meshes with rack piston 9, and the top end meshes with external rack 5.

[0050] Center rod 7:

[0051] 1. The center rod 7 is interference-fitted with the body 2, which is relatively fixed and sealed;

[0052] 2. The center rod 7 and the inner hole of the rack piston 9 are clearance-fitted, allowing the rack piston 9 to slide axially on the center rod 7 while maintaining a seal;

[0053] 3. A connecting port 8 is opened in the upper part of the center rod 7. When the rack piston 9 slides past the position of the connecting port 8, the channel opens and the liquid can flow from the upper inner hole of the body 2 through the inner hole of the center rod 7 to the lower inner hole of the body.

[0054] Hat 15:

[0055] 1. The back cap 15 is threaded to the upper end of the center rod 7, blocking the lower rack piston 9 and preventing the rack piston 9 from slipping out.

[0056] Rack and pinion piston 9:

[0057] 1. The inner hole of the rack piston 9 is clearance-fitted with the central rod 7, allowing the rack piston 9 to slide axially on the central rod 7 while maintaining a seal;

[0058] 2. The outer circle of the rack piston 9 is clearance-fitted with the body 2, and the rack piston 9 can slide axially and seal within the inner hole of the body 2;

[0059] 3. The lower end of the rack piston 9 has a return spring 10, which is always under pressure;

[0060] 4. When pressure is applied to the upper part of the tool, the rack piston 9 is compressed. When the pressure is greater than the spring force of the return spring 10 and the friction force, the rack piston 9 will move downward. When it moves to the open position of the connecting port 8 of the center rod 7, the channel opens and the fluid can flow downward.

[0061] When the hydraulic spear-catching sealing assembly of this utility model is not pressurized by the pump, it is in its original state. At this time, the rack piston 9 is in the upper limit position due to the thrust of the return spring 10, the sealing push ring 4 is in the lower limit position, the rubber part 12 of the sealing component 3 is closed, the diameter is small, smaller than the inner diameter of the fish, the sealing component 3 is in its original state, and no seal is formed with the inner wall of the fish. After the pump is started and pressurized, it is in a sealed state. The fishing spear and the hydraulic fishing spear sealing assembly are lowered into the inner hole of the fish, so that the fishing spear slips engage with the inner hole of the fish. At this time, the hydraulic fishing spear sealing assembly is also in the inner hole of the fish. The pump is started and pressurized. At this time, under the action of pressure difference, the rack piston 9 is pressed downward and the gear 6 rotates, driving the sealing push ring 4 to move upward, thereby squeezing the rubber part 12 of the sealing component 3 to expand outward and fit with the inner hole of the fish to form a seal. At this time, the channel at the connecting port 8 of the central rod 7 is opened, and the mud can flow downward through the water eye. The sealing component 3 is always in a sealed state. The mud flows to the outer annulus of the fish to flush the stuck debris in the outer annulus, so that the flushed stuck debris returns upward, reducing the stuck force of the fish. After the debris stuck in the outer ring is washed away, the fish can be retrieved simply by lifting the spear under the action of the spear and the fish biting each other. At this time, the pump stops, the pressure on the upper part of the rack piston 9 decreases, and the return spring 10 pushes the rack piston 9 to move upward. This will drive the sealing push ring 4 to move downward, and the rubber part 12 of the sealing component 3 will retract. There will be no seal between the hydraulic spear sealing assembly and the inner hole of the fish.

Claims

1. A hydraulic spear-retrieving sealing structure, characterized in that: It includes an upper connector (1), the lower end of which is connected to a body (2). A sealing component (3) and a sealing push ring (4) are fitted around the outer periphery of the body (2) from top to bottom. The sealing component (3) has a downward opening structure. An external rack (5) is fixed on the inner wall of the sealing push ring (4). An installation port is provided on the body (2). A gear (6) is provided at the installation port. The gear (6) meshes with the external rack (5). A central rod (7) is installed in the upper section of the large hole of the inner hole of the body (2). The inner hole of the central rod (7) is a blind hole structure with the upper end closed. The outer periphery of the upper end of the central rod (7) is provided with a connecting port (8) that communicates with the inner hole. The outer periphery of the central rod (7) is movably sleeved with a back cap (15), a rack piston (9) and a return spring (10) from top to bottom. The two ends of the rack piston (9) abut against the back cap (15) and the return spring (10) respectively. The rack piston (9) meshes with the gear (6). Under normal conditions, the rack piston (9) blocks the connecting port (8). The sealing component (3) includes a metal part (11) with a U-shaped structure and a rubber part (12) with an opening at the lower end. The upper end of the rubber part (12) is fitted into the metal part (11). The lower end of the sealing push ring (4) is provided with an axial groove (13), and the protruding rib (14) on the outer periphery of the upper end of the body (2) is inserted into the axial groove (13).

2. A hydraulic spear seal assembly as defined in claim 1, wherein: The lower end of the rubber part (12) is a horn mechanism with an outward opening, and the upper end of the sealing push ring (4) is a cone structure.

3. The hydraulic spear seal structure of claim 1, wherein: The bottom of the lower end of the central rod (7) is provided with a step, one end of the reset spring (10) abuts against the step, and a back cap (15) is threaded on the outer periphery of the upper end of the central rod (7).

4. The hydraulic spear seal structure of claim 1, wherein: The rack piston (9) has a rack structure in the middle and smooth surfaces at both ends.

5. The hydraulic spear seal structure of claim 1, wherein: The sealing push ring (4) has multiple external racks (5) arranged and fixed on the inner wall of the hole, and multiple mounting ports are arrayed on the body (2), with a gear (6) set at each mounting port.

6. The hydraulic spear seal structure of claim 1, wherein: Under normal conditions, the upper end of the sealing push ring (4) is embedded into the end opening of the sealing component (3).

7. The hydraulic spear seal structure of claim 1, wherein: The upper end face of the metal part (11) abuts against the lower end face of the upper connector (1).

Images