Plug-in connecting rod

Abstract

A plug-in connecting rod, comprising a first end (11), a rod body (12), an abutting portion (13), and a second end (14) that are sequentially connected, and further comprising a coupling sleeve (15) removably sleeved on the rod body (12), thereby improving the convenience of installation and maintenance.

Description

A plug-in connecting rod

[0001] Citation of relevant applications

[0002] This disclosure claims priority to Chinese patent application No. 202520706305.8, filed on April 15, 2025, entitled "A Plug-in Connecting Rod", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of oil and gas artificial lift technology, and in particular to a plug-in connecting rod. Background Technology

[0004] In manual lift operations, commonly used sucker rods consist of a rod body with rod heads at both ends. The rod heads are machined with external threads, and the threaded ends have shoulders. When connecting two sucker rods, the rod heads are joined together, and then connected using tubular couplings with internal threads at both ends. The two ends of the couplings are pre-tightened by pressing against the shoulder end faces. However, during actual lift operations, due to external forces, the sucker rods are prone to relative rotation. This can cause the threaded connection between the sucker rod and the coupling to loosen. Furthermore, to improve the anti-loosening capability, the locking area between the coupling end face and the shoulders needs to be further increased, directly leading to an increase in the coupling diameter and shoulder diameter. This increases the flow resistance of the extracted medium within the tubing, reducing extraction efficiency.

[0005] To address this issue, existing technology has improved the rod end of the sucker rod by designing a mating structure. During operation, a coupling, which slides onto the rod body, is pushed to the end, allowing the threads on the coupling to connect with the rod end threads of another sucker rod. However, this design has a significant drawback: the coupling cannot be detached from the rod body. During production, the coupling must first be fitted onto the sucker rod body before welding or other processing steps can be performed, undoubtedly increasing the complexity of the process. Furthermore, if the coupling is damaged during later use, it cannot be replaced, rendering the entire sucker rod unusable and significantly increasing maintenance costs.

[0006] Public content

[0007] This disclosure aims to at least partially address one of the technical problems in the related art. To this end, this disclosure provides a plug-in connecting rod that solves the technical problem of complex manufacturing processes and high maintenance costs for sucker rods.

[0008] To achieve the above objectives, the main technical solutions adopted in this disclosure include:

[0009] This disclosure provides a plug-in connecting rod, including a first end, a rod body, an abutment portion, and a second end connected in sequence; it also includes a coupling detachably sleeved on the rod body; the first end of one plug-in connecting rod can be plugged into the second end of another plug-in connecting rod; the coupling is used to simultaneously sleeve and screw onto the first end of one plug-in connecting rod and the second end of another plug-in connecting rod, and one end of the coupling abuts against the abutment portion adjacent to the second end.

[0010] Preferably, the inner walls at both ends of the coupling are provided with mating grooves; the inner diameter of the mating grooves is larger than the major diameter of the internal thread of the coupling.

[0011] Preferably, the first end of one plug-in connecting rod and the second end of another plug-in connecting rod are joined to form a mating end; a relief groove is provided in the middle of the coupling, and the relief groove is opposite to the mating end; the inner diameter of the relief groove is larger than the major diameter of the internal thread of the coupling.

[0012] Preferably, the first end has a plurality of first protrusions and the second end has a plurality of second protrusions; the plurality of first protrusions on the first end and the plurality of second protrusions on the second end are staggered; the first protrusion of the first end of a plug-in connecting rod can be plugged into a slot formed by two adjacent second protrusions of the second end of another plug-in connecting rod, and the first protrusion fits against the wall of the second protrusion; the plurality of first protrusions and the plurality of second protrusions cooperate to form a mating end.

[0013] Preferably, it further includes a locking nut detachably fitted onto the rod body; the locking nut is located at the tail end of the coupling and can be threadedly connected to the first end.

[0014] Preferably, the threads of the first end and the second end are in the same direction.

[0015] Preferably, a wrench groove is provided on the outer wall surface of the coupling.

[0016] Preferably, the first end and the rod body, as well as the abutment portion and the rod body, are connected by a circular arc transition.

[0017] Preferably, the minor diameter of the internal thread of the coupling is greater than the diameter of the rod body.

[0018] This disclosure discloses a plug-in connector rod, which, by comprising a first end, a rod body, an abutment portion, and a second end connected in sequence, and in conjunction with a detachable coupling fitted onto the rod body, greatly improves the convenience of installation and maintenance. It also avoids the complex steps of traditional sucker rod manufacturing, where the coupling is fitted onto the rod body before subsequent processing. Each component can be processed independently first, followed by final assembly, effectively simplifying the process. Furthermore, when the coupling is damaged, its detachable nature allows for easy replacement, preventing the entire sucker rod from being scrapped due to coupling damage. This significantly reduces maintenance costs and improves the sucker rod's service life and economic efficiency. Furthermore, in terms of connection, the first end of one connecting rod can be inserted into the second end of another connecting rod, enabling greater torque transmission. This connecting rod also overcomes the problem of rod loosening due to forward and reverse rotation of the sucker rod. It is secured to both ends with a coupling, the end of which abuts against the contact portion. This connection method greatly enhances stability, and the coupling's screw-on connection to both ends further increases the lifting weight of the connecting rod. In this connection structure, the coupling only serves to connect and lift the connecting rod; torque transmission and anti-loosening are achieved through the insertion of the connecting rod ends. This results in a smaller outer diameter for the coupling, reducing the flow resistance of the extraction medium within the pipe while maintaining strength, thus further increasing flow rate. Compared to traditional sucker rods, which are prone to relative rotation and thread loosening due to external forces during operation, this design effectively prevents relative rotation between connecting rods, ensuring stable operation in complex lifting environments and improving the efficiency and reliability of lifting operations. Attached Figure Description

[0019] The above and / or additional aspects and advantages of this disclosure will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0020] Figure 1 is a structural schematic diagram of a plug-in connecting rod of the present disclosure;

[0021] Figure 2 is a schematic diagram of the connection between two plug-in connecting rods.

[0022]

Explanation of reference numerals in the attached drawings

[0023] To better explain and facilitate understanding of this disclosure, the following detailed description of the disclosure is provided in conjunction with the accompanying drawings and specific embodiments.

[0024] As shown in Figure 1, this embodiment of the present disclosure provides a plug-in connecting rod 1, which includes a first end 11, a rod body 12, an abutment part 13 and a second end 14 connected in sequence, and also includes a coupling 15 detachably sleeved on the rod body 12.

[0025] As shown in Figure 2, the first end 11 of a plug-in connecting rod 1 can be plugged into the second end 14 of another plug-in connecting rod 1. A coupling 15 is used to simultaneously sleeve and screw onto the first end 11 of one plug-in connecting rod 1 and the second end 14 of another plug-in connecting rod 1, and one end of the coupling 15 abuts against the abutment portion 13 of the other plug-in connecting rod 1 adjacent to the second end 14. The minor diameter of the internal thread 152 of the coupling 15 is larger than the diameter of the rod body 12, and the thread directions of the first end 11 and the second end 14 are the same.

[0026] Because the plug-in connecting rod 1 includes a first end 11, a rod body 12, an abutment part 13, and a second end 14 connected in sequence, and is fitted with a detachable coupling 15 that is sleeved on the rod body 12, the convenience of installation and maintenance is greatly improved. It also avoids the complex steps of fitting the coupling onto the rod body 12 and then performing subsequent processing in the traditional sucker rod production process. Each component can be processed independently first, and then assembled, effectively simplifying the process. Secondly, when the coupling 15 is damaged, its detachable nature allows for easy replacement with a new coupling 15, preventing the entire connecting rod from being scrapped due to coupling damage. This significantly reduces maintenance costs and improves the service life and economy of the connecting rod.

[0027] Furthermore, in terms of connection, the first end 11 of one plug-in connecting rod 1 can be plugged into the second end 14 of another plug-in connecting rod 1, enabling greater torque transmission. This connecting rod can also overcome the problem of rod loosening caused by the forward and reverse rotation of the sucker rod. It is fitted with and screwed to both ends by a coupling 15, with the end of the coupling 15 abutting against the abutment part 13. This connection method greatly enhances the stability of the connection. The coupling, screwed to both ends, further increases the lifting weight of the connecting rod. In this connection structure, the coupling 15 only serves to connect and lift the connecting rod, while torque transmission and anti-loosening are achieved through the plugging of the connecting rod ends. Consequently, the outer diameter of the coupling 15 is smaller, reducing the flow resistance of the extraction medium within the pipe while ensuring strength, further increasing the flow rate. Compared to traditional sucker rods, which are prone to relative rotation and thread loosening due to external forces during operation, this design effectively prevents relative rotation between connecting rods, ensuring stable operation in complex lifting environments and improving the efficiency and reliability of lifting operations. Furthermore, the design of the minor diameter of the internal thread 152 of the coupling 15 being larger than the diameter of the rod 12 ensures that the coupling 15 can be smoothly fitted onto the rod 12 without affecting the normal operation of the rod 12, further optimizing the overall structural rationality. It should be noted that in this embodiment, the rigidity of the rod 12 is not limited. The rod 12 can be a flexible rod or a rigid rod, as long as the coupling 15 can move on the rod 12.

[0028] As shown in Figure 2, the inner walls of both ends of the coupling 15 are provided with mating grooves 151, the inner diameter of which is larger than the major diameter of the internal thread 152 of the coupling 15. When the two connecting rods are mated, the mating grooves 151 provide a larger space allowance, making the mating process smoother and reducing the difficulty of mating.

[0029] As shown in Figure 2, the first end 11 of one plug-in connecting rod 1 and the second end 14 of another plug-in connecting rod 1 are joined to form a mating end. A relief groove 153 is provided in the middle of the coupling 15, opposite to the mating end. The inner diameter of the relief groove 153 is larger than the major diameter of the internal thread 152 of the coupling 15. The relief groove 153 provides clearance space for the mating ends of the connecting rods, further optimizing the fit between the coupling 15 and the mating end. During the process of connecting rods being joined and coupling 15 being tightened, the relief groove 153 prevents the coupling 15 from causing unnecessary compression or obstruction to the mating end, ensuring a tight fit and thus improving the stability of the connection.

[0030] Specifically, the first end 11 has multiple first protrusions 111, and the second end 14 has multiple second protrusions 141. The multiple first protrusions 111 on the first end 11 and the multiple second protrusions 141 on the second end 14 are staggered. The first protrusions 111 of the first end 11 of one plug-in connecting rod 1 can be inserted one-to-one into the slots formed by two adjacent second protrusions 141 in the second end 14 of another plug-in connecting rod 1, with the first protrusion and the wall surface of the second protrusion fitting together. The multiple first protrusions 111 and the multiple second protrusions 141 cooperate to form a mating end. The multiple staggered protrusions increase the contact area and friction of the mating end, effectively preventing relative rotation or radial displacement between the two connecting rods under the complex external force environment of oil pumping operations, thereby improving the reliability of the connection, ensuring the efficient and stable operation of oil pumping, and improving the performance of the product. In this embodiment, the first end 11 includes two first protrusions 111 spaced apart, and the second end 14 includes two second protrusions 141 spaced apart. Two slots are formed between the two second protrusions 141, and the two first protrusions 111 in the first end 11 are correspondingly arranged with the two slots.

[0031] To further enhance the stability between the two connecting rods, the plug-in connecting rod 1 also includes a locking nut 16 detachably fitted onto the rod body 12. The locking nut 16 is located at the tail end of the coupling 15 and can be threadedly connected to the first end 11. After the coupling 15 is tightened, tightening the locking nut 16 applies additional axial force to the coupling 15, preventing it from loosening due to vibration or external forces during long-term use. This reduces the risk of connecting rod failure due to loose connection and improves the safety and reliability of the product. Of course, to facilitate the movement of the locking nut 16 on the rod body 12, the minor diameter of the internal thread of the locking nut 16 is larger than the diameter of the rod body 12. A wrench groove can also be provided on the locking nut 16 to facilitate installation or removal.

[0032] To facilitate the installation or removal of the coupling 15, a wrench groove 154 is provided on the outer wall surface of the coupling 15. The wrench groove 154 provides an easy point of application for the operator, who can use a wrench or other tools to insert into the wrench groove 154 to tighten or loosen the coupling 15 more easily. This reduces labor intensity and improves work efficiency.

[0033] To avoid stress concentration, the connection between the rod 12 and the first end 11, and between the abutment part 13 and the rod 12, are all connected by arc transitions. This allows the stress to be transmitted more evenly, reducing the possibility of fatigue damage due to stress concentration at the connection between the rod 12 and the first end 11, and at the connection between the rod 12 and the abutment part 13. This extends the service life of the connecting rod and improves the reliability and durability of the product.

[0034] Although embodiments of the present disclosure have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure. Those skilled in the art can make modifications, alterations, substitutions and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A splicing rod, characterized in that, It includes a first end (11), a rod (12), an abutment part (13), and a second end (14) connected in sequence; It also includes a coupling (15) that is detachably fitted onto the rod (12); The first end (11) of one of the plug-in connecting rods (1) can be plugged into the second end (14) of another plug-in connecting rod (1); The coupling (15) is used to simultaneously fit and screw onto the first end (11) of one of the plug-in connecting rods (1) and the second end (14) of another plug-in connecting rod (1), and one end of the coupling (15) abuts against the abutting part (13) adjacent to the second end (14).

2. The plug-in connecting rod according to claim 1, characterized in that: The inner walls at both ends of the coupling (15) are provided with mating grooves (151); The inner diameter of the mating groove (151) is larger than the major diameter of the internal thread (152) of the coupling (15).

3. The plug-in connecting rod according to claim 2, characterized in that: The first end (11) of one of the plug-in connecting rods (1) and the second end (14) of the other plug-in connecting rod (1) are joined to form a mating end; The coupling (15) has a relief groove (153) in the middle, and the relief groove (153) is opposite to the mating end; The inner diameter of the relief groove (153) is larger than the major diameter of the internal thread (152) of the coupling (15).

4. The plug-in connecting rod according to claim 3, characterized in that: The first end (11) has a plurality of first protrusions (111) at its end, and the second end (14) has a plurality of second protrusions (141) at its end; The plurality of first protrusions (111) on the first end (11) and the plurality of second protrusions (141) on the second end (14) are arranged alternately; The first protrusion (111) of the first end (11) of one of the plug-in connecting rods (1) can be plugged into the slot formed by two adjacent second protrusions (141) in the second end (14) of another plug-in connecting rod (1), and the first protrusion (111) fits against the wall of the second protrusion (141); Multiple first protrusions (111) and multiple second protrusions (141) cooperate to form the docking end.

5. The plug-in connecting rod according to claim 1, characterized in that: It also includes a locking nut (16) that is detachably fitted onto the rod (12); The locking nut (16) is located at the tail end of the coupling (15) and can be threadedly connected to the first end (11).

6. The plug-in connecting rod according to claim 1, characterized in that: The first end (11) and the second end (14) have the same thread direction.

7. The plug-in connecting rod according to claim 1, characterized in that: A wrench groove (154) is provided on the outer wall surface of the coupling (15).

8. The plug-in connecting rod according to claim 1, characterized in that: Both between the first end head (11) and the rod body (12) and between the abutting portion (13) and the rod body (12) are transitioned through a circular arc.

9. The splicing rod according to claim 1, characterized in that: The minor diameter of the internal thread (152) of the coupling (15) is greater than the diameter of the rod body (12).

Images