Mechanical puller oil drain

Abstract

The utility model relates to petroleum exploitation technical field discloses a kind of mechanical lifting type oil drainers, including upper joint, the end portion of the upper joint is equipped with first pressure cap, the connecting place of the upper joint and first pressure cap is fixedly connected with shear nail, the inner wall of the connecting place of the upper joint and first pressure cap is simultaneously inserted and is equipped with center tube, the pipe wall of the center tube is equipped with steel sleeve, the connecting place of the steel sleeve and first pressure cap is fixedly connected with first fixed pin.The upper joint provided by the utility model drives first pressure cap to move upward synchronously, shear nail bears upward tension force at this time, shear nail is sheared when tension force reaches the preset breaking strength of shear nail, relative motion is generated between upper joint and first pressure cap, steel sleeve, along with the continuous pulling of upper joint, originally closed oil passage is opened, forms the oil drain passage from the inside of center tube to outside through each gap, wellbore oil is discharged through the passage, realize oil drain function, improve use convenience.

Description

Technical Field

[0001] This utility model relates to the field of oil extraction technology, and in particular to a mechanical pull-out oil drainer. Background Technology

[0002] During pump inspection operations at rod pump wells, in order to prevent crude oil and wastewater in the tubing from being brought to the surface and polluting the environment, an oil drainer is usually installed on the production tubing string. During the pump inspection and tubing tripping process, the oil drainer can drain the oil and water in the tubing into the annulus. There are various types of oil drainers, such as pressure relief oil drainers, impact oil drainers, and sliding sleeve oil drainers.

[0003] The announcement number is CN207245673U, which discloses a hydraulic pressure-transmitting oil drain device, including an oil drain valve body. The upper end of the oil drain valve body is connected to the oil production tubing string, and the lower end of the oil drain valve body is connected to the oil pump. An oil drain hole communicating with the valve chamber is machined on the outer surface of the oil drain valve body. A sealing gasket is provided in the oil drain hole, and an arched rupture disc is provided on the outside of the sealing gasket. The announcement number is CN2174563Y. An impact-type oil drainer for well workover operations consists of a short section and a hollow drain screw. There is a side hole and a step on the inner wall of the short section. During operation, a heavy rod is thrown into the oil drainer to cut the screw and open the side hole. The crude oil remaining in the tubing can then flow into the annular space between the tubing and the casing, thus achieving the purpose of draining oil. In existing technologies, pressure relief valves require pressurization from the tubing during use, resulting in high operating costs and complex operation. Impact relief valves are installed between the fixed and traveling valves of the pump. During maintenance operations, after removing the original well rod and plunger, an impact rod is dropped from the tubing to break open the relief valve core, achieving annular connection and thus draining oil. However, for wells with broken rods, stuck pumps, or wax and scale buildup, the impact rod cannot be dropped into place, making it difficult to open the relief valve during operation and causing environmental pollution. Utility Model Content

[0004] The purpose of this invention is to solve the problems in the prior art by proposing a mechanical pull-out oil drainer.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A mechanical pull-out oil drain includes an upper connector, a first pressure cap fitted at the end of the upper connector, a shear pin fixedly connected at the connection between the upper connector and the first pressure cap, a central tube inserted into the inner wall of the connection between the upper connector and the first pressure cap, a steel sleeve fitted on the wall of the central tube, a first fixing pin fixedly connected at the connection between the steel sleeve and the first pressure cap, a second pressure cap fitted at the gap between the central tube and the steel sleeve, a second fixing pin fixedly connected at the connection between the second pressure cap and the central tube, and a lower connector inserted into the gap between the central tube and the steel sleeve at the end opposite to the upper connector.

[0006] Preferably, the inner walls of the upper connector, the central tube, and the lower connector are each provided with multiple chamfers.

[0007] Preferably, the inner wall of the upper connector is provided with an annular groove, and the upper connector is provided with a first sealing ring on the inner wall of the annular groove. The first sealing ring is pressed against the pipe wall of the central tube.

[0008] Preferably, a sealing ring is provided to fill the gap between the central tube and the steel sleeve, a second sealing ring is provided on the side wall of the sealing ring, and a gasket is provided on the side of the second sealing ring away from the sealing ring. The inner walls of the sealing ring, the second sealing ring and the gasket are respectively pressed tightly onto the tube wall of the central tube.

[0009] Preferably, the inner wall of the lower connector is provided with a third sealing ring and a first sealing retaining ring, and the third sealing ring and the first sealing retaining ring are respectively fitted onto the pipe wall of the central tube.

[0010] Preferably, a second sealing ring is fixedly connected to the outer wall of the lower connector, and the second sealing ring is fitted into the inner wall of the steel sleeve.

[0011] Compared with the prior art, this utility model provides a mechanical pull-out oil drainer, which has the following advantages: 1. This mechanical pull-up oil drainer moves the first pressure cap upward synchronously through the upper connector. At this time, the shear pin bears an upward tension. When the tension reaches the preset breaking strength of the shear pin, the shear pin is sheared. The upper connector, the first pressure cap, and the steel sleeve generate relative movement. As the upper connector is continuously pulled up, the originally closed oil passage is opened, forming an oil draining channel from the inside of the central tube through various gaps to the outside. The downhole oil is discharged through this channel, realizing the oil draining function and improving the convenience of use.

[0012] 2. In this mechanical pull-out oil drain, the sealing ring, the second sealing ring, and the gasket, which fill the gap between the central tube and the steel sleeve, are all pressed tightly against the wall of the central tube. The sealing ring provides a basic seal, the second sealing ring enhances the sealing effect, and the gasket prevents the sealing ring and the second sealing ring from failing due to pressure deformation.

[0013] 3. This mechanical pull-out oil drainer uses a third sealing ring and a first sealing retainer ring on the inner wall of the lower connector to adhere to the pipe wall of the central pipe, sealing the gap between the lower connector and the central pipe. The second sealing retainer ring on the outer wall of the lower connector adheres to the inner wall of the steel sleeve, further sealing the connection gap between the lower connector and the steel sleeve. The multiple sealing effects work together to ensure that oil will not leak from any connection points during normal downhole operations. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of a mechanical pull-out oil drain device proposed in this utility model; Figure 2 for Figure 1 Enlarged structural diagram of part A in the middle section; Figure 3 for Figure 1 A magnified schematic diagram of the structure of part B in the middle section.

[0015] In the diagram: 1 Upper connector, 2 First sealing ring, 3 Shear pin, 4 First pressure cap, 5 First fixing pin, 6 Center tube, 7 Steel sleeve, 8 Sealing ring, 9 Second sealing ring, 10 Washer ring, 11 Second pressure cap, 12 Second fixing pin, 13 Third sealing ring, 14 First sealing retaining ring, 15 Second sealing retaining ring, 16 Lower connector. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0017] Reference Figure 1-3 A mechanical pull-out oil drainer includes an upper connector 1, with a first pressure cap 4 fitted at the end of the upper connector 1. A shear pin 3 is fixedly connected to the connection between the upper connector 1 and the first pressure cap 4. A central tube 6 is inserted into the inner wall of the connection between the upper connector 1 and the first pressure cap 4. A steel sleeve 7 is fitted on the wall of the central tube 6. A first fixing pin 5 is fixedly connected to the connection between the steel sleeve 7 and the first pressure cap 4. A second pressure cap 11 is fitted into the gap between the central tube 6 and the steel sleeve 7. A second fixing pin 12 is fixedly connected to the connection between the second pressure cap 11 and the central tube 6. A lower connector 16 is inserted into the gap between the central tube 6 and the steel sleeve 7 at the end opposite to the upper connector 1.

[0018] The inner walls of the upper connector 1, the central tube 6 and the lower connector 16 are respectively provided with multiple chamfers. The inner wall of the upper connector 1 is provided with an annular groove. The upper connector 1 is provided with a first sealing ring 2 located on the inner wall of the annular groove. The first sealing ring 2 is pressed and set on the tube wall of the central tube 6.

[0019] A sealing ring 8 is provided to fill the gap between the central tube 6 and the steel sleeve 7. A second sealing ring 9 is provided on the side wall of the sealing ring 8. A gasket 10 is provided on the side of the second sealing ring 9 away from the sealing ring 8. The inner walls of the sealing ring 8, the second sealing ring 9 and the gasket 10 are respectively pressed tightly onto the tube wall of the central tube 6.

[0020] The upper connector 1 is the connecting component between the device and the upper tubing string, used to connect the drain valve to the downhole tubing system. In the initial state, the first pressure cap 4 fitted at the end of the upper connector 1 is fixedly connected to the upper connector 1 by shear pins 3. The strength of the shear pins 3 is preset to a specific value, which can withstand the pressure and tension during normal downhole operations, ensuring the initial structural stability of the device. The inner wall of the connection between the upper connector 1 and the first pressure cap 4 is connected to the central tube 6. The central tube 6 is the core channel for oil flow. The steel sleeve 7 fitted on its tube wall is fixed to the first pressure cap 4 by the first fixing pin 5, so that the steel sleeve 7 moves synchronously with the first pressure cap 4. The second pressure cap 11 fitted at the gap between the central tube 6 and the steel sleeve 7 is fixed to the central tube 6 by the second fixing pin 12, so as to achieve synchronous positioning of the second pressure cap 11 and the central tube 6 and avoid relative sliding between the two. The lower connector 16 is inserted at the gap between the central tube 6 and the steel sleeve 7 away from the upper connector 1. The lower connector 16 is used to connect the lower tubing string or downhole tools to form a complete downhole tubing passage.

[0021] The first sealing ring 2 in the annular groove on the inner wall of the upper connector 1 is pressed against the pipe wall of the central tube 6 to seal the gap between the upper connector 1 and the central tube 6. The sealing ring 8, the second sealing ring 9 and the gasket 10 filling the gap between the central tube 6 and the steel sleeve 7 are all pressed against the pipe wall of the central tube 6. The sealing ring 8 provides basic sealing, the second sealing ring 9 enhances the sealing effect, and the gasket 10 prevents the sealing ring 8 and the second sealing ring 9 from failing due to pressure deformation.

[0022] When oil drainage is required, the upper connector 1 is pulled upwards through the upper tubing string. The upper connector 1 drives the first pressure cap 4 to move upwards synchronously. At this time, the shear pin 3 bears an upward pulling force. When the pulling force reaches the preset breaking strength of the shear pin 3, the shear pin 3 is sheared, and the fixed relationship between the upper connector 1 and the first pressure cap 4 is released. The upper connector 1 is pulled upwards again, and the upper connector 1, the first pressure cap 4, and the steel sleeve 7 generate relative movement. At the same time, the central tube 6 remains relatively stationary due to its connection with the second pressure cap 11 and the lower connector 16. As the upper connector 1 is continuously pulled upwards, the relative position between the upper connector 1 and the central tube 6 changes, and the tight sealing state between the first sealing ring 2 and the central tube 6 is destroyed. At the same time, the sealing structure between the central tube 6 and the steel sleeve 7 and the lower connector 16 also loses its sealing effect due to the relative displacement between the components. The originally closed oil passage is opened, forming an oil drainage channel from the inside of the central tube 6 through various gaps to the outside. The downhole oil is discharged through this channel, realizing the oil drainage function.

[0023] To ensure that oil does not leak from various connection points during normal downhole operations, such as Figure 1-3 As shown, the inner wall of the lower connector 16 is provided with a third sealing ring 13 and a first sealing retaining ring 14. The third sealing ring 13 and the first sealing retaining ring 14 are respectively attached to the pipe wall of the central pipe 6. The outer wall of the lower connector 16 is fixedly connected with a second sealing retaining ring 15, which is attached to the inner wall of the steel sleeve 7.

[0024] The third sealing ring 13 and the first sealing retaining ring 14 on the inner wall of the lower connector 16 are respectively attached to the pipe wall of the central pipe 6 to seal the gap between the lower connector 16 and the central pipe 6. The second sealing retaining ring 15 on the outer wall of the lower connector 16 is attached to the inner wall of the steel sleeve 7 to further seal the connection gap between the lower connector 16 and the steel sleeve 7. The multiple sealing works together to ensure that oil will not leak from the connection parts during normal downhole operations.

[0025] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A mechanical pull-out type oil drainer, comprising an upper connector (1), characterized in that: The upper connector (1) is fitted with a first pressure cap (4) at its end. A shear pin (3) is fixedly connected to the connection between the upper connector (1) and the first pressure cap (4). A central tube (6) is inserted into the inner wall of the connection between the upper connector (1) and the first pressure cap (4). A steel sleeve (7) is fitted on the wall of the central tube (6). A first fixing pin (5) is fixedly connected to the connection between the steel sleeve (7) and the first pressure cap (4). A second pressure cap (11) is fitted into the gap between the central tube (6) and the steel sleeve (7). A second fixing pin (12) is fixedly connected to the connection between the second pressure cap (11) and the central tube (6). A lower connector (16) is inserted into the gap between the central tube (6) and the steel sleeve (7) away from the upper connector (1).

2. The mechanical pull-out oil drainer according to claim 1, characterized in that: The inner walls of the upper connector (1), the central tube (6) and the lower connector (16) are respectively provided with multiple chamfers.

3. The mechanical pull-out oil drainer according to claim 1, characterized in that: The upper connector (1) has an annular groove on its inner wall. The upper connector (1) has a first sealing ring (2) on the inner wall of the annular groove. The first sealing ring (2) is pressed against the wall of the central tube (6).

4. The mechanical pull-out oil drainer according to claim 1, characterized in that: A sealing ring (8) is provided to fill the gap between the central tube (6) and the steel sleeve (7). A second sealing ring (9) is provided on the side wall of the sealing ring (8). A gasket (10) is provided on the side of the second sealing ring (9) away from the sealing ring (8). The inner walls of the sealing ring (8), the second sealing ring (9) and the gasket (10) are respectively pressed against the tube wall of the central tube (6).

5. A mechanical pull-out oil drainer according to claim 1, characterized in that: The inner wall of the lower connector (16) is provided with a third sealing ring (13) and a first sealing retainer ring (14), which are respectively attached to the pipe wall of the central tube (6).

6. A mechanical pull-out oil drainer according to claim 1, characterized in that: The outer wall of the lower connector (16) is fixedly connected to a second sealing ring (15), which is fitted into the inner wall of the steel sleeve (7).

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