Sucker rod

Abstract

The invention discloses a sucker rod, and relates to the technical field of oil well equipment. The sucker rod comprises a rod body, a first flange used for being matched with a rod grabbing device is arranged on the rod body, a second flange used for being matched with a supporting device is further arranged on the rod body, the second flange is located on the side, close to the middle of the rod body, of the first flange, and an avoiding section used for the rod grabbing device to conduct rod grabbing operation is arranged between the second flange and the first flange. The first flange and the second flange are matched with the grabbing rod device and the supporting device correspondingly, interference is not prone to occurring, and automation of well repair is achieved conveniently.

Description

Technical Field

[0001] The invention belongs to the technical field of oil well equipment, and in particular relates to a sucker rod. Background Art

[0002] When an oil well is repaired, the sucker rod needs to be pulled out and then lowered after the repair is completed. Currently, the raising and lowering of the sucker rod requires manual work with the help of repair equipment.

[0003] Generally, each section of the sucker rod is provided with a flange at the end thereof for cooperation with the elevator. In the process of pulling out and lowering the sucker rod, two elevators are required to be used in cooperation. First, use an elevator to clamp onto the flange of the sucker rod and lift the sucker rod. When one section of the sucker rod is lifted, the operator clamps another elevator under the flange of the next section of the sucker rod. The elevator seat at the wellhead supports the sucker rod and prevents the sucker rod from falling. At this time, the sucker rod can be removed, and then the next section of the sucker rod can be lifted. Repeat the above operation to complete the pulling out of the sucker rod.

[0004] The above-mentioned elevator can refer to the Chinese utility model patent with authorization announcement number CN217151872U and announcement date August 9, 2022. The patent discloses a hydraulically powered sucker rod elevator, which includes an elevator body, a elevator opening is provided on the front side of the elevator body, and two side doors for closing the opening are symmetrically hinged on both sides of the elevator opening, and a first hydraulic cylinder for driving the side door to rotate is respectively provided between the elevator body and each side door.

[0005] In the process of raising and lowering the sucker rod, the above technical solution requires manual operation to insert the sucker rod from the opening of the elevator into the elevator body. And when in use, the two elevators move up and down alternately. In order to avoid collision between the two elevators, a safe distance must be maintained between the two elevators and between the elevators and the sucker rod. The existing sucker rod can only be raised and lowered in the above manner. In this process, the two elevators make the structure of the well repair equipment complicated, the movement process of the elevators is complicated, the control is difficult, and it is not easy to realize automatic operation. Summary of the invention

[0006] The purpose of the present invention is to provide a sucker rod to solve the technical problem that the sucker rod structure in the prior art can only use two elevators to lift the sucker rod alternately up and down, resulting in a complex well repair equipment structure and difficulty in realizing automated operation.

[0007] To achieve the above purpose, the technical solution provided by the present invention is:

[0008] A sucker rod comprises a rod body, wherein the rod body is provided with a first flange for cooperating with a rod grabbing device, and the rod body is also provided with a second flange for cooperating with a supporting device, wherein the second flange is located on a side of the first flange close to the middle of the rod body, and an avoidance section for the rod grabbing device to perform a rod grabbing operation is provided between the second flange and the first flange.

[0009] The beneficial effect is that the above technical solution is a further improvement of the prior art. Since the first flange and the second flange are arranged on the rod body, the first flange can be used as a matching position for the grabbing device to grab the sucker rod, and the second flange can be used as a matching position for the supporting device to temporarily support the sucker rod. The grabbing operation and the supporting operation do not interfere with each other, and the grabbing device can move straight up and down, which is convenient for operation and easy to realize the automatic control of the process. And only one grabbing device is needed to complete the operation of raising and lowering the sucker rod, so that the overall structure of the well repair equipment is simplified.

[0010] As a further improvement, at least one side of the first flange and / or the second flange is formed with a transition portion having an eight-shaped structure in a longitudinal section.

[0011] The beneficial effect is that the transition part can avoid stress concentration caused by sudden change of cross section, avoid stress corrosion and increase the service life of the sucker rod.

[0012] As a further improvement, the length of the transition portion on one side of the first flange and / or the second flange close to the middle of the rod body is greater than the length of the transition portion on the other side.

[0013] The beneficial effect is that the transition part with a longer length needs to contact the support device or the grab bar device, so the longer length can make its cross-section change more gradually, which can effectively avoid stress concentration. The transition part with a shorter length does not need to contact the support device or the grab bar device, so its shorter length can save the space occupied by the first flange or the second flange.

[0014] As a further improvement, the end of the rod body is also provided with a threaded section for interconnection and a twisting section for rotating the rod body, the twisting section is formed with at least one torsion matching surface, and the twisting section and the threaded section are located on the side of the second flange away from the first flange.

[0015] The beneficial effect is that the threaded section is formed with an external thread for connecting with the coupling. The twisting section is convenient for rotating the sucker rod using a tool such as a wrench to complete the connection between the sucker rod and the coupling.

[0016] As a further improvement, at least two torsion fitting surfaces are provided, and each torsion fitting surface is arranged around the center of the rod body.

[0017] The beneficial effects are: easy to manufacture and operate.

[0018] As a further improvement, the torsion fitting surface and the axis of the rod body are parallel to each other.

[0019] The beneficial effect is that it is convenient for operators to perform the rotating operation.

[0020] As a further improvement, a unloading section is provided between the threaded section and the twisting section, and the unloading section is a bare rod structure.

[0021] The beneficial effect is that the unloading section reduces the stress concentration caused by the change of the thread and the cross section, and improves the fatigue resistance of the sucker rod.

[0022] As a further improvement, a shoulder for limiting the screwing depth of the threaded section is provided between the twisting section and the unloading section.

[0023] The beneficial effect is that when the sucker rod is connected to the coupling, the coupling is tightened and the end face of the coupling is abutted against the end face of the shoulder to generate pressure, thereby effectively preventing the sucker rod from being disengaged during use, achieving good sealing, and preventing well fluid from corroding the thread. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the overall structure of Embodiment 1 of the present invention;

[0025] Figure 2 This is a schematic diagram of Example 1 of the present invention when in use.

[0026] Description of reference numerals:

[0027] 1. Rod body; 2. Threaded section; 3. Unloading section; 4. Shoulder; 5. Twisting section; 6. First flange; 7. Avoidance section; 8. Second flange; 9. Well plugging device; 10. Support device; 11. Rod grabbing device. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, that is, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0029] The present invention is further described in detail below in conjunction with embodiments.

[0030] Specific embodiment 1 provided by the present invention:

[0031] See attached Figure 1A sucker rod comprises a rod body 1, the end of which is provided with a threaded section 2, a relief section 3, a shoulder 4, a twisting section 5, a first flange 6, an avoidance section 7 and a second flange 8 in sequence from outside to inside.

[0032] The threaded section 2 is formed with an external thread for connecting with a coupling connected to an adjacent rod body. When the sucker rod is connected with the coupling, the coupling is tightened so that the end face of the coupling abuts against the end face of the shoulder 4 and generates pressure, thereby effectively preventing the sucker rod from being disengaged during use, and effectively improving the sealing between the coupling and the shoulder, and preventing the well fluid from corroding the thread.

[0033] The unloading section 3 is located between the shoulder 4 and the thread section 2, and is used to reduce the stress concentration caused by the thread and the cross-section change, and improve the fatigue resistance of the sucker rod.

[0034] The twisting section 5 is formed with at least one torsion matching surface parallel to the axis of the rod body. In order to facilitate processing and operation, the twisting section 5 in this embodiment is a quadrangular prism structure, and the four side walls of the quadrangular prism structure constitute the force-bearing surface. In other embodiments, the twisting section can also be a hexagonal prism structure.

[0035] The first flange 6 and the second flange 8 are integrally formed with the rod body 1. A transition section with an eight-shaped longitudinal section is formed on the side of the first flange 6 away from the torsion section 5 and on both sides of the second flange 8 to reduce stress concentration. And the length of the transition section on one side of the first flange 6 and the second flange 8 close to the middle of the rod body 1 is greater than the length of the transition section on the other side. The transition section with a longer length has a smoother cross-sectional change, which can effectively avoid stress concentration. The transition section with a shorter length can save the space occupied by the first flange or the second flange. The edges of the first flange 6 and the second flange 8 are formed with rounded corners to avoid scratching the oil pumping equipment.

[0036] See attached Figure 2 A support device 10 is installed on the well plug 9, and the support device 10 can be opened and closed. After the support device 10 is closed, the second flange 8 can sit down on the support device 10, so that the sucker rod is suspended and supported at the wellhead by the support device 10. The grabbing rod device 11 grabs the avoidance section 7 between the first flange 6 and the second flange 8, and the sucker rod is clamped on the grabbing rod device 11 by the first flange 6.

[0037] When lifting the sucker rod, first use the grabbing rod device 11 to grab the avoidance section 7 on the first sucker rod, lift the first sucker rod, and when the height of the second flange 8 of the second sucker rod exceeds the supporting device 10 installed on the well plug 9, operate the supporting device 10 to close it, lower the sucker rod so that the second flange 8 on the second sucker rod sits on the supporting device 10, so that the sucker rod is suspended and supported at the wellhead by the supporting device 10. Then remove the first sucker rod, lower the traveling block of the well repair equipment, and lower the grabbing rod device 11 suspended on the traveling block together. When the grabbing rod device 11 is lowered to the avoidance section 7 of the second sucker rod, the grabbing rod device 11 grabs the avoidance section 7 of the second sucker rod, and the first flange 6 is stuck on the grabbing rod device 11 to ensure the stability of the sucker rod during the lifting process. Then, the sucker rod is lifted up by the grabbing rod device 11. When the second flange 8 of the second sucker rod moves upward and detaches from the supporting device 10, the supporting device 10 is operated to open it until the height of the second flange 8 of the third sucker rod exceeds the supporting device 10. Then, the supporting device 10 is operated to close it, so that the third sucker rod is suspended and supported at the wellhead. Repeat the above operation to complete the sucker rod lifting operation. The sucker rod lowering operation can be completed by reverse operation. The supporting device 10 and the grabbing rod device 11 in this embodiment are both prior art and will not be described in detail here.

[0038] The first flange 6 and the second flange 8 are used to cooperate with the grabbing rod device 11 and the supporting device 10 respectively, and the operation of grabbing the sucker rod by the grabbing rod device 11 and the operation of supporting the sucker rod by the supporting device 10 will not interfere with each other. In addition, compared with the prior art, the sucker rod in this embodiment can be raised and lowered with one grabbing rod device, the well repair equipment has a simple structure, the grabbing rod device can move straight up and down, the movement process is relatively simple, and automatic control is easy to achieve.

[0039] The specific embodiment 2 provided by the present invention is different from the embodiment 1 mainly in that: in this embodiment, the second flange is connected to the rod body by welding.

[0040] The specific embodiment 3 provided by the present invention is different from the embodiment 1 mainly in that: in this embodiment, the cross-sectional shape of the second flange is a rectangular structure.

[0041] The specific embodiment 4 provided by the present invention differs from the embodiment 1 mainly in that: in this embodiment, the outer wall of the twist section is composed of an arc surface and a plane, and the intersection of the arc surface and the plane forms two edges parallel to the axis of the rod body. In this embodiment, the plane constitutes the twist mating surface.

[0042] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions recorded in the aforementioned embodiments without creative work, or replace some of the technical features therein with equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A sucker rod, comprising a rod body, wherein the rod body is provided with a first flange for cooperating with a gripping rod device, wherein: The rod body is also provided with a second flange for cooperating with the supporting device, the second flange is located on the side of the first flange close to the middle of the rod body, and between the second flange and the first flange is an avoidance section for the rod grabbing device to perform the rod grabbing operation.

2. The sucker rod according to claim 1, characterized in that: At least one side of the first flange and / or the second flange is formed with a transition portion having an eight-shaped structure in the longitudinal section.

3. The sucker rod according to claim 2, characterized in that: The length of the transition portion on one side of the first flange and / or the second flange close to the middle of the rod body is greater than the length of the transition portion on the other side.

4. The sucker rod according to any one of claims 1 to 3, characterized in that: The end of the rod body is also provided with a threaded section for mutual connection and a twisting section for rotating the rod body, the twisting section is formed with at least one torsion matching surface, and the twisting section and the threaded section are located on the side of the second flange away from the first flange.

5. The sucker rod according to claim 4, characterized in that: There are at least two torsion matching surfaces, and each torsion matching surface is arranged around the center of the rod body.

6. The sucker rod according to claim 4, characterized in that: The torsion fitting surface and the axis of the rod body are parallel to each other.

7. The sucker rod according to claim 4, characterized in that: A load-relief section is also provided between the threaded section and the twisting section, and the load-relief section is a bare rod structure.

8. The sucker rod according to claim 7, characterized in that: A shoulder for limiting the screwing depth of the threaded section is provided between the twisting section and the unloading section.

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