Double-layer sucker rod

Abstract

The utility model discloses a double-layer sucker rod which comprises a plurality of sections of sucker rods which are detachably connected, and the structure of each sucker rod comprises an outer ring, an inner ring and an inner ring, the inner ring is arranged in the outer ring in a sleeved mode, a gap is formed between the outer ring and the upper half portion of the inner ring, the outer ring is fixedly connected with the lower half portion of the inner ring through a fixing ring, and a limiting ring in sliding connection is arranged on the middle section of the outer ring and the middle section of the inner ring; the connecting shaft sleeve is of a multi-ring structure, the connecting shaft sleeve is detachably connected with the sucker rod, and two adjacent sections of sucker rods form a double-layer sucker rod of a multi-section structure through the connecting shaft sleeve; the inner ring is sleeved with the spring, one end of the spring is fixed to the limiting ring, and the other end of the spring is fixed to the connecting shaft sleeve. According to the double-layer sucker rod, the problems that fixing rings connected between sucker rods and connecting rings are loosened along with increase of the depth of a drilling well, oil leakage occurs, and even direct tripping and disconnection occur are solved.

Description

Technical Field

[0001] The utility model relates to a sucker rod for oil production in oil fields, in particular to a double-layer sucker rod. Background Technique

[0002] The sucker rod is a slender rod of a pumping well. It is connected to the polished rod at the upper end and the subsurface pump at the lower end to transmit power. The single length of the sucker rod is 7.6 or 8 meters. The material is generally high-carbon steel with a hard chromium plating on the surface. It is connected by internal thread collars one by one in the oil pipe and extends to the piston at the underground oil layer. Oil is pumped through reciprocating motion. Currently, the length of oil wells is generally about 2,000 meters, and even the deepest can reach more than 3,000 meters.

[0003] In order to adapt to oil wells of different depths, the sucker rods available on the market are generally connected to each other. However, during use, it will increase the pressure at the connection of the sucker rods, resulting in excessive pressure at the connection of the sucker rods and causing problems such as fracture.

[0004] To solve this problem, a new type of sucker rod with the application number: 201721801434.7 is provided. The two ends are fixed on the protection pipe through connection rings. However, there is a problem that the fixing ring connecting the sucker rod and the connection ring is prone to looseness, which may cause oil leakage or even direct unthreading, resulting in the sucker rod breaking directly in the middle of the pumping well. Content of the Utility Model

[0005] An object of the utility model is to solve at least the above problems and / or defects, and provide at least the advantages described later.

[0006] To achieve these objects and other advantages according to the utility model, a double-layer sucker rod is provided, including:

[0007] Multiple sections of detachable sucker rods, wherein the structure of each sucker rod includes:

[0008] An outer ring;

[0009] An inner ring, which is sleeved in the outer ring, and there is a gap between the upper halves of the outer ring and the inner ring. The lower halves of the outer ring and the inner ring are fixedly connected by a fixing ring, and a limiting ring with a sliding connection is arranged in the middle section of the outer ring and the inner ring;

[0010] A connecting bushing, which is a multi-ring structure. The connecting bushing is detachably connected to the sucker rod, and a multi-section double-layer sucker rod structure is formed between adjacent two sections of sucker rods through the connecting bushing;

[0011] A spring, which is sleeved on the inner ring, and one end of the spring is fixed to the limiting ring, and the other end is fixed to the connecting bushing.

[0012] Preferably, the structure of the connecting bushing includes:

[0013] O-shaped disc;

[0014] Outer ring, which is arranged on the outer circle of the O-shaped disc;

[0015] Inner ring, which is arranged on the inner circle of the O-shaped disc;

[0016] Middle ring, which is arranged in the middle section of the O-shaped disc and between the outer ring and the inner ring. The middle ring is located in the lower half of the O-shaped disc. A spring is arranged at the lower end of the middle ring, and the spring is fixed to the limit ring. The width of the middle ring is adapted to the gap between the outer circle and the inner circle, and the middle ring is embedded in the gap.

[0017] Preferably, threads are arranged at both ends of the inner side of the outer ring, threads are arranged at both ends of the outer wall of the outer circle, and the outer ring is threadedly connected to the outer circle.

[0018] Preferably, threads are arranged at both ends of the outer side of the inner ring, threads are arranged at both ends of the inner circle, and the inner ring is threadedly connected to the inner circle.

[0019] Preferably, a first group of limit grooves are arranged inside the outer circle, a second group of limit grooves are arranged outside the inner circle, and the limit ring is slidably embedded in the first group of limit grooves and the second group of limit grooves.

[0020] The utility model has at least the following beneficial effects:

[0021] A double-layer sucker rod of the utility model connects and fixes adjacent double-layer sucker rods through a set connection shaft sleeve to form a multi-section structure, and can be assembled by itself according to the length of the oil well during actual use;

[0022] The multi-ring design of the connection shaft sleeve can effectively share the pressure generated during the oil pumping process of adjacent double-layer sucker rods and prevent liquid overflow at the same time;

[0023] The built-in spring can offset part of the pressure of the connection shaft sleeve through elasticity to avoid its disconnection and ensure the normal progress of the oil pumping operation.

[0024] Other advantages, objectives and features of the utility model will be partially reflected by the following description and partially understood by those skilled in the art through the research and practice of the utility model. Brief Description of the Drawings

[0025] Figure 1 It is a schematic cross-sectional structure diagram of the utility model;

[0026] Figure 2 It is a schematic overall structure diagram of the utility model;

[0027] Figure 3Schematic cross-sectional structure diagram of the connecting bushing of the present utility model;

[0028] Figure 4 Schematic structure diagram of the limit ring of the present utility model Detailed implementation manners

[0029] The following further describes the present utility model in detail with reference to the accompanying drawings, so that those skilled in the art can implement it according to the description in the specification.

[0030] It should be understood that terms such as "having", "including", and "comprising" used herein do not exclude the presence or addition of one or more other elements or their combinations.

[0031] It should be noted that in the description of the present utility model, the orientation or positional relationship indicated by the terms is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0032] In the description of the present utility model, unless otherwise clearly defined and limited, terms such as "installed", "provided with", "sheathed / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection, can be a mechanical connection, can be an electrical connection, can be directly connected, or can be indirectly connected through an intermediate medium, and can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0033] In addition, in the present utility model, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "below" and "beneath" the second feature can be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0034] The following describes the present experimental model in detail with reference to the accompanying drawings:

[0035] Figures 1-3 A double-layer sucker rod of the present utility model is shown, including:

[0036] The sucker rod 10 with multi - section detachable connection, wherein the structure of each sucker rod 10 includes:

[0037] An outer ring 11;

[0038] An inner ring 12, which is sleeved inside the outer ring 11, and there is a gap between the upper halves of the outer ring 11 and the inner ring 12. The lower halves of the outer ring 11 and the inner ring 12 are fixedly connected by a fixing ring 14, and a limiting ring 13 with a sliding connection is arranged in the middle section between the outer ring 11 and the inner ring 12;

[0039] A connecting bushing 20, which has a multi - ring structure. The connecting bushing 20 is detachably connected to the sucker rod 10, and a double - layer sucker rod with a multi - section structure is formed between two adjacent sucker rods 10 through the connecting bushing 20;

[0040] A spring 30, which is sleeved on the inner ring 12, and one end of the spring 30 is fixed to the limiting ring 13 and the other end is fixed to the connecting bushing 20.

[0041] Working principle:

[0042] The main body of the sucker rod 10 is composed of the outer ring 11 and the inner ring 12 sleeved. The lower half of the outer ring 11 and the lower half of the inner ring 12 are welded by a fixing ring 14 to connect and fix the outer ring 11 and the inner ring 12 (there is no gap between the inner ring 12 and the outer ring 11 in the lower half), and a limiting ring 13 is arranged in the middle so that the spring 30 can be slidably connected in the gap between the outer ring 11 and the inner ring 12. Between two adjacent sucker rods 10, the detachable connection between the sucker rod 10 and the connecting bushing 20 is a threaded connection. The docking of multiple - section sucker rods 10 is realized by using the connecting bushing 20 to form a whole double - layer sucker rod to go deep into the oil well for operation;

[0043] When the liquid starts to work inside the sucker rod 10, the liquid enters the inner ring 12. At this time, because the sucker rod 10 adopts a double - layer design, by directly contacting the sandstone wall of the oil well through the outer ring 11, the inner ring 12 for transporting oil can be protected, improving the service life of the double - layer sucker rod. At the same time, the gap between the inner ring 12 and the outer ring 11 can also prevent the leakage of liquid;

[0044] During the connection process, the spring 30 is sleeved in the gap between the outer ring 11 and the inner ring 12. The lower end of the spring 30 is fixed to the limit ring 13. At this time, when the sucker rod 10 and the connecting bushing 20 are fixed, the spring 30 is in a normal state. At this time, due to the up and down movement of the sucker rod 10 during work, the connecting bushing 20 and the sucker rod 10 move outward, and at this time the spring 30 is in a state of being stretched outward. The spring 30 exerts an upward force on the sucker rod 10 and a downward force on the connecting bushing 20, so that the sucker rod 10 will not break due to the loosening of the connecting bushing 20. At the same time, it also plays a certain auxiliary role in correcting the center of gravity deviation caused by the deepening between multiple sucker rods 10. The design of the double-layer sucker rod with multiple joints connected can be adjusted according to the actual depth of the oil well. If a problem occurs in one section, it is more convenient to replace than a whole sucker rod, saving costs.

[0045] In the above solution, the structure of the connecting bushing 20 includes:

[0046] O-shaped disc 21;

[0047] Outer ring 22, which is arranged on the outer ring of the O-shaped disc 21;

[0048] Inner ring 23, which is arranged on the inner ring of the O-shaped disc 21;

[0049] Middle ring 24, which is arranged in the middle section of the O-shaped disc 21 and is located between the outer ring 22 and the inner ring 23. The middle ring is located in the lower half of the O-shaped disc 21. A spring 30 is arranged at the lower end of the middle ring 24. The spring 30 is fixed to the limit ring 13. The width of the middle ring 24 is adapted to the gap between the outer ring 11 and the inner ring 12, and the middle ring is embedded in the gap.

[0050] Working principle:

[0051] During the pumping operation, when the outer ring 11 and the inner ring 12 on the sucker rod 10 are docked with the outer ring 22 and the inner ring 23 provided on the connecting bushing 20, one end of the spring 30 is fixed to the lower end of the middle ring 24, and the other end of the spring 30 is connected to the limit block 13. Then the middle ring 24 is embedded in the gap between the outer ring 11 and the inner ring 12. The middle ring 24 is only arranged between the lower half outer ring 22 and the inner ring 23 of the connecting bushing 20. The middle ring 24 is not arranged between the outer ring 22 and the inner ring 23 of the other half of the connecting bushing 20. The lower end of the upper connected sucker rod 10 is directly docked with the outer ring 22 and the inner ring 23 provided on the upper end of the connecting bushing 20 through the outer ring 11 and the inner ring 12;

[0052] When the sucker rod 10 and the connecting bushing 20 are not completely spliced, the spring 30 is in a state of being stretched at both ends at this time. When the spring 30 is sleeved into the gap between the inner ring 12 and the outer ring 11, the connecting bushing 20 starts to be threadedly connected to the sucker rod 10. At this time, the spring 30 is still in a stretched state. When both ends are fixed, the spring 30 is in a normal state. If the connection loosens, it provides a downward tensile force for the connecting bushing 20 and an upward tensile force for the sucker rod, thereby effectively avoiding the problem that the connecting bushing 20 may accidentally loosen and fall off during the use of the sucker rod 10. When the spring is in a stretched state and retracts, the tightened elastic force pulls the sucker rod 10 and the connecting bushing 20 at both ends tightly to prevent falling off. In addition, when multiple sections of the sucker rod 10 go deep into the oil well, due to a certain deviation in the drilling, the center of gravity of the sucker rod 10 becomes more and more off as it goes deeper. The spring 30 can also use its own stretching to straighten the sucker rod 10;

[0053] The O-shaped disc 21 on the connecting bushing 20 is set as a multi-ring structure. When connecting the sucker rod 10, there are two layers of structures, the inner ring 23 and the middle ring 24, to prevent the overflow of liquid, and there are two layers of mechanisms, the outer ring 22 and the middle ring 24, outside to prevent sand and gravel from entering the sucker rod 10.

[0054] In the above solution, threads are provided at both ends of the inner side of the outer ring 22, threads are provided at both ends of the outer wall of the outer ring 11, and the outer ring 22 is threadedly connected to the outer ring 11.

[0055] In the above solution, threads are provided at both ends of the outer side of the inner ring 23, threads are provided at both ends of the inner ring 12, and the inner ring 23 is threadedly connected to the inner ring 12.

[0056] Working principle:

[0057] Adjacent sucker rods 10 are threadedly connected through the outer ring 11 and the outer ring 22, and the inner ring 12 and the inner ring 23, so as to use the connecting bushing 20 to realize the docking of multiple sections of double-layer sucker rods, forming a complete double-layer sucker rod to go deep into the oil well for operation. The design of the double-layer sucker rod 10 can effectively prevent the leakage of internal liquid and the entry of external sand and gravel, and improve the working life of the sucker rod 10.

[0058] In the above solution, a first set of limiting grooves 110 is provided inside the outer ring 11, a second set of limiting grooves 120 is provided outside the inner ring 12, and the limiting ring 13 is slidably embedded in the first set of limiting grooves 110 and the second set of limiting grooves 120.

[0059] Working principle:

[0060] The width of the recessed gap between the first group of limiting grooves 110 and the second group of limiting grooves 120 is adapted to be embedded with the width of the protruding parts at both ends of the limiting ring 13. Through the limiting ring 13, the spring 30 can be driven to be embedded between the outer ring 11 and the inner ring 12 (the gap between the outer ring 11 and the inner ring 12 is greater than the radius of the spring forming center, which satisfies the sleeving of the spring 30 and will not cause wear between the inner wall of the outer ring 11 and the outer wall of the inner ring 12 during rotation). Through the sliding connection mode of the first group of limiting grooves 110 and the second group of limiting grooves 120 with the limiting ring 13 (when the connecting shaft sleeve 20 drives the spring 30 to be rotationally connected to the sucker rod 10, the first group of limiting grooves 110 and the second group of limiting grooves 120 can provide a rotatable space for the limiting ring 13), when the sucker rod 10 is threadedly connected to both ends of the connecting shaft sleeve 20, the spring 30 can maintain a certain rotation and will not cause excessive frictional damage to the inner ring 12 and the outer ring 11 of the sucker rod 10.

[0061] Although the embodiments of the present invention have been disclosed above, it is not limited to the applications listed in the specification and embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the field, additional modifications can be easily achieved. Therefore, without departing from the general concept defined by the claims and the equivalent scope, the present invention is not limited to the specific details and the illustrated and described examples here.

Claims

1. A double-layer sucker rod, characterized in that, Comprising: A sucker rod with multiple sections detachably connected. Among them, the structure of each sucker rod includes: An outer ring; An inner ring, which is sleeved inside the outer ring, and there is a gap between the upper halves of the outer ring and the inner ring. The lower halves of the outer ring and the inner ring are fixedly connected by a fixing ring, and a limiting ring with a sliding connection is arranged in the middle section of the outer ring and the inner ring; A connecting shaft sleeve, which is a multi-ring structure. The connecting shaft sleeve is detachably connected to the sucker rod, and a double-layer sucker rod with a multi-section structure is formed between adjacent two sections of sucker rods through the connecting shaft sleeve; A spring, which is sleeved on the inner ring, and one end of the spring is fixed to the limiting ring, and the other end is fixed to the connecting shaft sleeve.

2. The double-layer sucker rod according to claim 1, wherein, The structure of the connecting shaft sleeve includes: An O-shaped disc; An outer ring, which is arranged on the outer circle of the O-shaped disc; An inner ring, which is arranged on the inner circle of the O-shaped disc; A middle ring, which is arranged in the middle section of the O-shaped disc and is located between the outer ring and the inner ring. The middle ring is located in the lower half of the O-shaped disc, and a spring is arranged at the lower end of the middle ring, and the spring is fixed to the limiting ring. The width of the middle ring is adapted to the gap between the outer ring and the inner ring, and the middle ring is embedded in the gap.

3. The double-layer sucker rod according to claim 2, wherein Threads are arranged at both ends of the inner side of the outer ring, and threads are arranged at both ends of the outer wall of the outer ring. The outer ring is threadedly connected to the outer ring.

4. The double-layer sucker rod according to claim 2, wherein, Threads are arranged at both ends of the outer side of the inner ring, and threads are arranged at both ends of the inner ring. The inner ring is threadedly connected to the inner ring.

5. The double-layer sucker rod according to claim 1, characterized in that, A first group of limiting grooves are arranged inside the outer ring, and a second group of limiting grooves are arranged outside the inner ring. The limiting ring is slidably embedded in the first group of limiting grooves and the second group of limiting grooves.

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