An oil production well extraction string

Abstract

The utility model discloses an oil production well pumping pipe column, which comprises: an oil layer casing pipe, a large oil pipe is sleeved in the oil layer casing pipe, a small oil pipe is sleeved in the large oil pipe, a conversion joint is installed at the bottom end of the large oil pipe, a sealing spigot is installed at the bottom end of the small oil pipe, a sealing cylinder is installed at the top end of the conversion joint, a lower oil pipe is communicated at the bottom end of the conversion joint, the conversion joint is provided with two independent and up-down through flow channels, the lower oil pipe is communicated with the annulus between the large oil pipe and the small oil pipe through one flow channel of the conversion joint, the small oil pipe is communicated with the oil layer through the other flow channel of the conversion joint, a forward check valve is installed in the lower oil pipe, and a pumping unit is installed in the small oil pipe. The utility model adds medicine in the annulus of the large and small oil pipes, the medicine is mixed with the oil layer production fluid through the conversion joint and the lower oil pipe, and then enters the small oil pipe through the conversion joint and the sealing spigot, and is pumped to the ground by the pumping unit, thereby solving the problem that the medicine cannot be added to the underground in the oil well production when there is a dead oil ring in the oil jacket annulus.

Description

Technical Field

[0001] This utility model relates to the field of oil well production tubing technology, and in particular to an oil well extraction tubing. Background Technology

[0002] During oil well production, the formation water has complex properties; some is corrosive, some is prone to scaling, and some crude oil has a high wax content, making the tubing prone to wax formation. Usually, it is necessary to add corrosion inhibitors, scale inhibitors, and wax removers and preventers through the annulus. However, when the crude oil has a high wax content and a high pour point, dead oil rings are easily formed in the annulus. The presence of dead oil rings prevents the agents from being added to the well through the annulus, forcing the company to periodically inspect the pump, replace the tubing and sucker rod, etc., which is costly. Utility Model Content

[0003] The purpose of this utility model is to provide an oil well production tubing string that allows for chemical injection through the annulus of the large and small tubing. The chemical is mixed with the produced fluid from the oil layer via a conversion joint and the lower tubing, and then enters the small tubing through the conversion joint and the sealed insertion pipe. It is then pumped to the surface by the oil pump, solving the problem of chemical injection not being able to reach the wellbore during production in oil wells with dead oil rings in the annulus.

[0004] To achieve the purpose of this utility model, this utility model provides an oil well production tubing string, comprising: an oil layer casing, a large oil pipe sleeved inside the oil layer casing, a small oil pipe sleeved inside the large oil pipe, a conversion joint installed at the bottom end of the large oil pipe, a sealing insert installed at the bottom end of the small oil pipe, a sealing cylinder installed at the top end of the conversion joint, the bottom end of the sealing insert being inserted into and sealed to the sealing cylinder, the small oil pipe being connected to the conversion joint through the insertion structure of the sealing insert and the sealing cylinder, a lower oil pipe being connected to the bottom end of the conversion joint, the conversion joint having two independent and vertically connected flow channels, the lower oil pipe being connected to the annulus between the large and small oil pipes through one flow channel of the conversion joint, the small oil pipe being connected to the oil layer through the other flow channel of the conversion joint, a positive flow valve installed inside the lower oil pipe, and a pumping pump installed inside the small oil pipe.

[0005] As a preferred embodiment of this utility model, the top of the oil pump is connected to a sucker rod.

[0006] As a preferred embodiment of this utility model, the sealing tube is a through-tube structure, comprising an upper connector, an intermediate body, a lower connector, and a sealing element. The upper connector, intermediate body, and lower connector are sequentially threaded together. The upper end of the upper connector is threadedly connected to the bottom end of the small oil tube, and the lower end of the upper connector is a small-diameter section used to fit the sealing element. The upper end of the intermediate body is threadedly connected to the bottom end of the upper connector, and the upper end face of the intermediate body presses against the sealing element. The lower end of the intermediate body is a small-diameter section used to fit the sealing element. The upper end of the lower connector is threadedly connected to the lower end of the intermediate body, and the upper end face of the lower connector presses against the sealing element.

[0007] As a preferred embodiment of this utility model, the lower end face of the lower connector is provided with a horseshoe-shaped guide shoe.

[0008] As a preferred technical solution of this utility model, the sealing cylinder is a through-hole structure. The through hole of the sealing cylinder includes a large-diameter section, a small-diameter section and a step. The small-diameter section is located below the large-diameter section, and the top of the small-diameter section transitions to the bottom of the large-diameter section through the step. The bottom end of the sealing tube is inserted into the large-diameter section until it abuts against the step. The outer wall of the bottom end of the sealing cylinder is provided with external threads and is threadedly connected to the adapter.

[0009] As a preferred embodiment of this utility model, the conversion connector includes a body and a screen sleeve. The body is a cylindrical body with unequal diameters and a smaller outer diameter at the top. The screen sleeve is fitted onto the body, and a joint annulus is formed between the inner wall of the screen sleeve and the outer wall of the body. One end of the screen sleeve is threaded to the larger diameter section of the body. The top of the body is provided with a first threaded upper interface and a second threaded upper interface, and the diameter of the second threaded upper interface is smaller than that of the first threaded upper interface. The bottom of the body is provided with a threaded lower interface. The outer wall of the screen sleeve has several screen holes. The body has a central blind hole, an eccentric hole, and a radial through hole. The eccentric hole and the radial through hole are circumferentially spaced. There are two eccentric holes. The two ends of the eccentric hole are respectively connected to the first threaded upper interface and the threaded lower interface. The joint annulus is connected to the screen holes. The top of the central blind hole is connected to the second threaded upper interface. The two ends of the radial through hole are respectively connected to the central blind hole and the joint annulus.

[0010] As a preferred embodiment of this utility model, the first threaded upper interface is threadedly connected to the large oil pipe, the first threaded lower interface is threadedly connected to the lower oil pipe, and the lower oil pipe is connected to the annulus between the large oil pipe and the small oil pipe through the flow channel of the eccentric hole.

[0011] As a preferred embodiment of this utility model, the second threaded interface is threadedly connected to the sealing cylinder, and the oil layer is connected to the sealing cylinder through the flow channels of the sieve hole, the joint annulus, the radial perforation and the central blind hole.

[0012] As a preferred embodiment of this utility model, a plug is installed at the bottom end of the lower oil pipe, and a screen pipe is installed between the plug and the positive flow valve.

[0013] Compared with the prior art, this utility model provides an oil well production tubing string with the following beneficial effects:

[0014] This invention utilizes annular dosing of chemicals through both large and small tubing. The chemicals mix with the produced fluid from the oil layer via a conversion joint and the lower tubing, then enter the smaller tubing through the conversion joint and a sealed insert, and are pumped to the surface by a pump. This solves the problem of chemicals not being able to be delivered downhole in wells with dead oil rings in the annulus. The dosing path is as follows: the chemicals enter the eccentric orifice channel through the annulus between the large and small tubings, and then enter the lower tubing. The oil discharge path is as follows: after mixing with the produced fluid, the chemicals enter the channels of the screen holes, the joint annulus, the radial perforation, and the central blind hole through the lower tubing, and then enter the smaller tubing through the sealed cylinder and the upper sealed insert, and are pumped to the surface. The same path can also be used for reverse circulation well washing. Furthermore, during normal production, due to the forward flow valve structure and the dual-channel structure of the conversion joint, the two channels in the conversion joint are independent of each other. Crude oil produced from the formation cannot enter the annulus of the large and small oil pipes through the conversion joint, thus preventing the formation of dead oil rings in the annulus of the large and small oil pipes. This greatly extends the time required for pump inspection, oil pipe replacement, sucker rod replacement, and other operations, thereby reducing production costs. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model;

[0016] Figure 2 This is a schematic diagram of the sealing cannula structure of this utility model;

[0017] Figure 3 This is a schematic diagram of the sealing cylinder structure of this utility model;

[0018] Figure 4 This is a schematic diagram of the adapter structure of this utility model;

[0019] Figure 5 This is a schematic diagram of the radial cross-sectional structure of the adapter of this utility model.

[0020] 1 is the oil layer casing, 2 is the large oil pipe, 3 is the small oil pipe, 4 is the conversion joint, 5 is the sealing insert, 6 is the sealing cylinder, 7 is the lower oil pipe, 8 is the oil layer, 9 is the positive check valve, 10 is the oil pump, 11 is the sucker rod, 13 is the upper joint, 14 is the intermediate body, 15 is the lower joint, 16 is the seal, 17 is the horseshoe-shaped guide shoe, 18 is the large diameter section, 19 is the small diameter section, 20 is the step, 21 is the body, 22 is the screen sleeve, 23 is the joint annulus, 24 is the first thread upper interface, 25 is the second thread upper interface, 26 is the thread lower interface, 27 is the screen hole, 28 is the central blind hole, 29 is the eccentric hole, 30 is the radial perforation, 31 is the plug, 32 is the screen tube, and 33 is the dead oil ring. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] Please see Figures 1-5 This utility model provides an oil well production tubing string, including: an oil layer casing 1, a large oil pipe 2 sleeved inside the oil layer casing 1, a small oil pipe 3 sleeved inside the large oil pipe 2, a conversion joint 4 installed at the bottom end of the large oil pipe 2, a sealing insert 5 installed at the bottom end of the small oil pipe 3, a sealing cylinder 6 installed at the top end of the conversion joint 4, the bottom end of the sealing insert 5 being inserted and sealed to the sealing cylinder 6, the small oil pipe 3 being connected to the conversion joint 4 through the insertion structure of the sealing insert 5 and the sealing cylinder 6, the bottom end of the conversion joint 4 being connected to a lower oil pipe 7, the conversion joint 4 having two independent and vertically connected flow channels, the lower oil pipe 7 being connected to the annulus between the large oil pipe 2 and the small oil pipe 3 through one flow channel of the conversion joint 4, and the small oil pipe 3 being connected to the oil layer 8 through the other flow channel of the conversion joint 4, a positive flow valve 9 installed inside the lower oil pipe 7, and an oil pump 10 installed inside the small oil pipe 3.

[0023] In one embodiment of the present invention, the top of the oil pump 10 is connected to a sucker rod 11.

[0024] In one embodiment of this utility model, the sealing tube 5 is a through-tube structure and includes an upper connector 13, an intermediate body 14, a lower connector 15, and a sealing element 16. The upper connector 13, the intermediate body 14, and the lower connector 15 are sequentially threaded together. The upper end of the upper connector 13 is threadedly connected to the bottom end of the small oil tube 3. The lower end of the upper connector 13 is a small-diameter section used to fit the sealing element 16. The upper end of the intermediate body 14 is threadedly connected to the bottom end of the upper connector 13, and the upper end face of the intermediate body 14 presses against the sealing element 16. The lower end of the intermediate body 14 is a small-diameter section used to fit the sealing element 16. The upper end of the lower connector 15 is threadedly connected to the lower end of the intermediate body 14, and the upper end face of the lower connector 15 presses against the sealing element 16.

[0025] In one embodiment of this utility model, the lower end face of the lower connector 15 is provided with a horseshoe-shaped guide shoe 17.

[0026] In one embodiment of this utility model, the sealing cylinder 6 is a through-hole structure. The through hole of the sealing cylinder 6 includes a large diameter section 18, a small diameter section 19, and a step 20. The small diameter section 19 is located below the large diameter section 18, and the top of the small diameter section 19 transitions to the bottom of the large diameter section 18 through the step 20. The bottom end of the sealing tube 5 is inserted into the large diameter section 18 until it abuts against the step 20. The outer wall of the bottom end of the sealing cylinder 6 is provided with external threads and is threadedly connected to the conversion connector 4.

[0027] In one embodiment of this utility model, the adapter 4 includes a body 21 and a screen sleeve 22. The body 21 is a cylindrical body with unequal diameters and a smaller outer diameter at the top. The screen sleeve 22 is fitted onto the body 21, and a joint annular space 23 is formed between the inner wall of the screen sleeve 22 and the outer wall of the body 21. One end of the screen sleeve 22 is threaded to the larger diameter section of the body 21. The top of the body 21 is provided with a first threaded upper interface 24 and a second threaded upper interface 25, and the diameter of the second threaded upper interface 25 is smaller than that of the first threaded upper interface 24. The bottom end of the body 21 is provided with a thread. The lower interface 26 has a plurality of screen holes 27 on the outer wall of the screen sleeve 22. The body 21 has a central blind hole 28, an eccentric hole 29 and a radial through hole 30. The eccentric hole 29 and the radial through hole 30 are circumferentially spaced apart. There are two eccentric holes 29. The two ends of the eccentric hole 29 are respectively connected to the first threaded upper interface 24 and the threaded lower interface 26. The joint annular space 23 is connected to the screen holes 27. The top end of the central blind hole 28 is connected to the second threaded upper interface 25. The two ends of the radial through hole 30 are respectively connected to the central blind hole 28 and the joint annular space 23.

[0028] In one embodiment of this utility model, the first threaded upper interface 24 is threadedly connected to the large oil pipe 2, the threaded lower interface 26 is threadedly connected to the lower oil pipe 7, and the lower oil pipe 7 is connected to the annulus between the large oil pipe 2 and the small oil pipe 3 through the flow channel of the eccentric hole 29.

[0029] In one embodiment of this utility model, the second threaded upper interface 25 is threadedly connected to the sealing cylinder 6, and the oil layer 8 is connected to the sealing cylinder 6 through the flow channels of the sieve hole 27, the joint annulus 23, the radial perforation 30 and the central blind hole 28.

[0030] In one embodiment of this utility model, a plug 31 is installed at the bottom end of the lower oil pipe 7, and a screen pipe 32 is installed between the plug 31 and the positive flow valve 9.

[0031] The above are merely preferred embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this utility model, based on the technical solution and inventive concept of this utility model, should be included within the scope of protection of this utility model.

Claims

1. An oil well production tubing string, characterized in that, include: An oil layer casing (1) is provided, with a large oil pipe (2) fitted inside the casing (1). A small oil pipe (3) is fitted inside the large oil pipe (2). A conversion joint (4) is installed at the bottom end of the large oil pipe (2). A sealing insert (5) is installed at the bottom end of the small oil pipe (3). A sealing cylinder (6) is installed at the top end of the conversion joint (4). The bottom end of the sealing insert (5) is inserted into and sealed to the sealing cylinder (6). The small oil pipe (3) is connected to the conversion joint (4) through the insertion structure of the sealing insert (5) and the sealing cylinder (6). The connector (4) is connected to a lower oil pipe (7) at its bottom end. The connector (4) is provided with two independent and vertically connected flow channels. The lower oil pipe (7) is connected to the annulus between the large oil pipe (2) and the small oil pipe (3) through one flow channel of the connector (4). The small oil pipe (3) is connected to the oil layer (8) through the other flow channel of the connector (4). A positive flow valve (9) is installed in the lower oil pipe (7). An oil pump (10) is installed in the small oil pipe (3).

2. The oil well production tubing string according to claim 1, characterized in that: The top of the oil pump (10) is connected to a sucker rod (11).

3. The oil well production tubing string according to claim 1, characterized in that: The sealing tube (5) is a through tube structure and includes an upper connector (13), an intermediate body (14), a lower connector (15), and a seal (16). The upper connector (13), the intermediate body (14), and the lower connector (15) are connected by threads in sequence. The upper end of the upper connector (13) is threaded to the bottom end of the small oil tube (3). The lower end of the upper connector (13) is set as a small diameter section, which is used to fit the seal (16). The upper end of the intermediate body (14) is threaded to the bottom end of the upper connector (13), and the upper end face of the intermediate body (14) is pressed against the seal (16). The lower end of the intermediate body (14) is set as a small diameter section, which is used to fit the seal (16). The upper end of the lower connector (15) is threaded to the lower end of the intermediate body (14), and the upper end face of the lower connector (15) is pressed against the seal (16).

4. The oil well production tubing string according to claim 3, characterized in that: The lower end face of the lower connector (15) is provided with a horseshoe-shaped guide shoe (17).

5. The oil well production tubing string according to claim 1, characterized in that: The sealing cylinder (6) is a through-hole structure. The through hole of the sealing cylinder (6) includes a large diameter section (18), a small diameter section (19) and a step (20). The small diameter section (19) is located below the large diameter section (18), and the top of the small diameter section (19) transitions to the bottom of the large diameter section (18) through the step (20). The bottom end of the sealing tube (5) is inserted into the large diameter section (18) until it reaches the step (20). The outer wall of the bottom end of the sealing cylinder (6) is provided with external threads and is threadedly connected to the conversion connector (4).

6. The oil well production tubing string according to claim 1, characterized in that: The adapter (4) includes a body (21) and a screen sleeve (22). The body (21) is a cylindrical body with an unequal diameter and a smaller outer diameter at the top. The screen sleeve (22) is fitted onto the body (21). A joint annulus (23) is formed between the inner wall of the screen sleeve (22) and the outer wall of the body (21). One end of the screen sleeve (22) is threaded to the larger diameter section of the body (21). The top of the body (21) is provided with a first threaded upper interface (24) and a second threaded upper interface (25), and the diameter of the second threaded upper interface (25) is smaller than that of the first threaded upper interface (24). The bottom of the body (21) is provided with a threaded lower interface (26). The outer wall of the sieve sleeve (22) is provided with a number of sieve holes (27). The body (21) is provided with a central blind hole (28), an eccentric hole (29) and a radial through hole (30). The eccentric hole (29) and the radial through hole (30) are circumferentially spaced. There are two eccentric holes (29). The two ends of the eccentric hole (29) are respectively connected to the first threaded upper interface (24) and the threaded lower interface (26). The joint annulus (23) is connected to the sieve hole (27). The top end of the central blind hole (28) is connected to the second threaded upper interface (25). The two ends of the radial through hole (30) are respectively connected to the central blind hole (28) and the joint annulus (23).

7. The oil well production tubing string according to claim 6, characterized in that: The first threaded upper interface (24) is threadedly connected to the large oil pipe (2), and the threaded lower interface (26) is threadedly connected to the lower oil pipe (7). The lower oil pipe (7) is connected to the annulus between the large oil pipe (2) and the small oil pipe (3) through the flow channel of the eccentric hole (29).

8. The oil well production tubing string according to claim 6, characterized in that: The second threaded interface (25) is threadedly connected to the sealing cylinder (6), and the oil layer (8) is connected to the sealing cylinder (6) through the flow channels of the sieve hole (27), the joint annulus (23), the radial perforation (30) and the central blind hole (28).

9. The oil well production tubing string according to claim 1, characterized in that: A plug (31) is installed at the bottom of the lower oil pipe (7), and a screen pipe (32) is installed between the plug (31) and the positive flow valve (9).

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