Integrated hollow rod lifting safety joint

Abstract

The invention relates to the field of petroleum and natural gas well exploitation, in particular to an integrated hollow rod lifting safety connector to solve the problems that after a screw pump is stuck, a hollow rod can be taken out only by sawing while lifting in an existing connecting mode, and the production cost and the maintenance difficulty are increased. The device comprises a shearing structure, the shearing structure is arranged between the upper joint and the lower joint; the shearing structure can transmit torque force to a stator of the screw pump and can be separated from the stator when the stator is stuck. According to the scheme, through the application of the shearing structure, when the pump is stuck, the hollow rod is lifted upwards, the shearing structure is broken, the upper connector is separated from the lower connector, the hollow rod is pulled out quickly, the maintenance process is greatly simplified, and the working efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of oil and gas well development, and in particular to an integrated hollow rod lifting safety joint. Background Technology

[0002] Screw pumps are widely used in oil and gas well production. However, due to the extremely complex and harsh bottom-hole environment, screw pumps often face a series of malfunctions during actual operation. The working environment of screw pumps is typically filled with high temperature, high pressure, and corrosive media, which can lead to performance degradation or even failure of the equipment.

[0003] Common problems encountered during oil well extraction include wax deposition, sand production, and scale buildup. These issues not only affect the normal operation of screw pumps but can also lead to pump jamming. Specifically, wax deposition occurs when paraffin wax in crude oil precipitates and adheres to the surfaces of pipes and equipment under low-temperature conditions, forming a solid wax layer that obstructs fluid flow. Sand production is caused by unstable formations, allowing sand particles to enter the wellbore, wear down equipment, and clog flow channels. Scale buildup refers to the deposition of minerals on equipment surfaces, forming a hard, scale-like layer that reduces equipment efficiency.

[0004] When a screw pump jams, it typically requires overhauling and inspecting the pump to restore production capacity. However, most current screw pump designs use a hollow rod direct connection method. When the screw pump rotor is jammed, it cannot be directly removed; a method of simultaneous lifting and sawing is necessary. This method not only consumes a lot of manpower and time but also causes significant waste of raw materials from the oil well, increasing production costs and maintenance difficulty.

[0005] Therefore, improving the reliability of screw pumps in harsh downhole environments has become an urgent problem to be solved in the oil and gas extraction field. Summary of the Invention

[0006] This invention provides an integrated hollow rod lifting safety connector to alleviate the problem that existing connection methods require simultaneous lifting and sawing to remove the hollow rod after a screw pump jams, which increases production costs and maintenance difficulty.

[0007] To alleviate the above-mentioned technical problems, the technical solution provided by the present invention is as follows:

[0008] This invention provides an integrated hollow rod lifting safety connector, including a shearing structure;

[0009] The shearing structure is located between the upper and lower joints;

[0010] The shearing structure can transmit torque to the stator of the screw pump and can separate from the stator when the stator is jammed.

[0011] Furthermore,

[0012] The shear structure includes a square plug-in body;

[0013] The four-sided connector has a first recessed hole at the top and a second recessed hole at the bottom;

[0014] There is a through slot between the first recess and the second recess;

[0015] The first recessed hole is connected to the upper connector thread via an internal thread;

[0016] The lower connector is inserted into the second recessed hole;

[0017] The lower connector is fixedly connected to the second recessed hole by a shearing nail.

[0018] Furthermore,

[0019] The second concave hole has an axially symmetrical first connecting hole on its sidewall.

[0020] The upper connector has a second connecting hole that mates with the first connecting hole;

[0021] The cutting nail runs through the first connecting hole and the second connecting hole.

[0022] Furthermore,

[0023] The upper part of the lower connector is provided with a protrusion;

[0024] The protrusion and the slot are slidably connected.

[0025] Furthermore,

[0026] The slot cross-section is rectangular;

[0027] The cross-section of the bump is a rectangle that matches the slot.

[0028] Furthermore,

[0029] The cross-sectional shape of the slot is symmetrical with respect to the axial center of the square connector.

[0030] Furthermore,

[0031] There is a gap between the lower part of the upper connector and the upper part of the protrusion.

[0032] Furthermore,

[0033] The upper connector sidewall is provided with a back nut.

[0034] The beneficial effects of the integrated hollow rod lifting safety connector in this invention are analyzed as follows:

[0035] This device includes a shearing structure positioned between the upper and lower connectors. The shearing structure transmits torque to the stator of the screw pump and can separate from the stator when it jams. This solution, through the application of the shearing structure, enables the hollow rod to be lifted and broken when the pump is jammed, separating the upper and lower connectors. This allows for the rapid removal of the hollow rod, greatly simplifying the maintenance process and improving work efficiency. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the specific embodiments or related technologies of the present invention, the drawings used in the description of the specific embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 A schematic diagram of the integrated hollow rod lifting safety connector provided for an embodiment of the present invention;

[0038] Figure 2 for Figure 1 A schematic diagram of the cross-section at point AA.

[0039] icon:

[0040] 100 - Shearing structure; 110 - Square plug-in body; 120 - Shearing pin;

[0041] 200 - Upper connector; 210 - Back nut;

[0042] 300 - Lower connector; 310 - Protrusion. Detailed Implementation

[0043] When a screw pump jams, it typically requires overhauling and inspecting the pump to restore production capacity. However, most current screw pump designs use a hollow rod direct connection method. When the screw pump rotor is jammed, it cannot be directly removed; a method of simultaneous lifting and sawing is necessary. This method not only consumes a lot of manpower and time but also causes significant waste of raw materials from the oil well, increasing production costs and maintenance difficulty.

[0044] In view of this, this solution provides an integrated hollow rod lifting safety connector to alleviate the above problems.

[0045] This device includes a shearing structure 100;

[0046] The shearing structure 100 is disposed between the upper connector 200 and the lower connector 300;

[0047] The shearing structure 100 can transmit torque to the screw pump stator and can separate from the screw pump stator when the screw pump stator is jammed.

[0048] Specifically, the upper part of the shearing structure 100 is detachably connected to the hollow rod, and the lower part is fixedly connected to the screw pump stator. Under normal operating conditions of the screw pump, the shearing structure 100 can transmit torque to the screw pump stator normally, just like the hollow rod. When the screw pump stator jams and cannot work normally, a pulling force of more than 120KN is used to lift the hollow rod, which will cause the shearing structure 100 to break, separate the hollow rod from the screw pump stator, and allow the sucker rod string to be lifted out smoothly.

[0049] Regarding the shape and structure of the shear structure 100, such as Figure 1 and Figure 2 As shown:

[0050] The shear structure 100 includes a square plug-in body 110;

[0051] The square connector 110 has a first recessed hole at the top and a second recessed hole at the bottom;

[0052] There is a through slot between the first recess and the second recess;

[0053] The first recessed hole is connected to the upper connector 200 thread via an internal thread;

[0054] The lower connector 300 is inserted into the second recessed hole;

[0055] The lower connector 300 is fixedly connected to the second recessed hole by the shearing nail 120.

[0056] Specifically, the four-sided connector 110 has a first recess and a second recess at both ends, which are connected by a slot. The first recess has an internal thread for detachable connection with the upper connector 200. The lower connector 300 is inserted into the second recess and extends into the slot.

[0057] In this design, the second concave hole sidewall is provided with an axially symmetrical first connecting hole;

[0058] The upper connector 200 has a second connecting hole that mates with the first connecting hole;

[0059] The shear nail 120 runs through the first and second connecting holes.

[0060] Specifically, the dimensions of the shearing nail 120 are set according to the weight of the lower part of the lower connector 300 and the outer diameter of the square plug body 110. After installation, both ends of the shearing nail 120 are located in the first connecting hole.

[0061] In this design, a protrusion 310 is provided on the upper part of the lower connector 300;

[0062] The protrusion 310 is slidably connected to the slot.

[0063] Specifically, the protrusion 310 is engaged in the slot to transmit the torque generated by the screw pump to the lower screw pump stator; the connection structure between the protrusion and the slot is used to bear the torque force, so that the shear pin 120 will not be affected by the torque force and break, and the effect is the same as that of the hollow rod.

[0064] More preferably, the slot cross-section is rectangular;

[0065] The cross-section of the protrusion 310 is a rectangle that matches the slot, making it easier to assemble and disassemble the square connector 110 and the lower connector 300. The torque force of the screw pump can be transmitted without the need for interference fit. Furthermore, when the screw pump stator is jammed, the protrusion 310 can smoothly separate from the slot without separation failure.

[0066] In this design, the cross-sectional shape of the slot is symmetrical with respect to the central axis of the square connector 110, which facilitates the processing of the slot and improves its service life.

[0067] In this design, there is a gap between the lower part of the upper connector 200 and the upper part of the protrusion 310 to prevent the upper connector 200 from abutting against the protrusion 310 during installation, which would cause stress concentration and abnormal breakage of the shear nail 120.

[0068] In this solution, the upper connector 200 has a back nut 210 on its side wall. When using this tool, the upper part of the upper connector 200 is inserted into the hollow rod. After insertion, the back nut 210 needs to be rotated to move to one side of the hollow rod in order to lock the hollow rod and the upper connector 200.

[0069] This solution has at least the following beneficial effects:

[0070] Existing technology requires significant manpower and time for simultaneous sawing and prying when the screw pump stator is jammed. This process is not only cumbersome but also wastes a lot of materials, increasing production costs. This solution, through the application of the shearing structure 100, achieves rapid separation of the hollow rod from the screw pump stator when the pump is jammed, greatly simplifying the maintenance process and improving work efficiency.

[0071] In its specific design, the dimensions of the shear pin 120 are precisely set according to the weight of the equipment and the outer diameter of the square connector 110, ensuring stable transmission of torque under normal operating conditions and reliable breakage and separation in the event of pump jamming, thus guaranteeing the safety and reliability of the equipment. The sliding connection design of the protrusion 310 and the slot allows the torque to be effectively transmitted to the lower pump stator without applying additional stress to the shear pin 120, thereby avoiding abnormal breakage of the shear pin in non-jamming conditions and further improving the durability of the device.

[0072] Furthermore, the design of the four-sided plug-in body 110 simplifies the installation and disassembly process of the connector. The internal thread and plug-in design reduce interference fits, making operation more convenient. The spacing design between the upper connector 200 and the protrusion 310 effectively prevents stress concentration caused by contact during installation, further optimizing the safety of the shearing structure. The back nut 210 on the side wall of the upper connector 200 locks the hollow rod and upper connector by rotating the back nut, ensuring the firmness and stability of the connection and increasing the reliability of the device.

[0073] In summary, this device not only solves the problem of rapid maintenance when the screw pump stator is jammed, but also improves the safety, convenience and reliability of operation by optimizing the force transmission mechanism and structural design. It significantly reduces material waste and production costs, effectively improves production efficiency and reduces maintenance difficulty.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An integrated hollow rod lifting safety connector, characterized in that: Includes shear structure (100); The shearing structure (100) is disposed between the upper connector (200) and the lower connector (300); The shearing structure (100) can transmit torque to the stator of the screw pump and can separate from the stator when the stator is jammed.

2. The integrated hollow rod lifting safety connector according to claim 1, characterized in that: The shearing structure (100) includes a square plug-in body (110); The square connector (110) has a first recessed hole on the upper part and a second recessed hole on the lower part; A through slot is provided between the first recess and the second recess; The first recessed hole is threadedly connected to the upper connector (200) via an internal thread; The lower connector (300) is inserted into the second recessed hole; The lower connector (300) is fixedly connected to the second recessed hole by a shear pin (120).

3. The integrated hollow rod lifting safety connector according to claim 2, characterized in that: The second concave hole sidewall is provided with an axially symmetrical first connecting hole; The upper connector (200) has a second connecting hole that mates with the first connecting hole; The shearing nail (120) passes through the first connecting hole and the second connecting hole.

4. The integrated hollow rod lifting safety connector according to claim 3, characterized in that: The upper part of the lower connector (300) is provided with a protrusion (310); The protrusion (310) is slidably connected to the slot.

5. The integrated hollow rod lifting safety connector according to claim 4, characterized in that: The slot has a rectangular cross-section; The cross-section of the protrusion (310) is a rectangle that matches the slot.

6. The integrated hollow rod lifting safety connector according to claim 5, characterized in that: The cross-sectional shape of the slot is symmetrical with respect to the axial center of the square connector (110).

7. The integrated hollow rod lifting safety connector according to claim 6, characterized in that: There is a gap between the lower part of the upper connector (200) and the upper part of the protrusion (310).

8. The integrated hollow rod lifting safety connector according to claim 7, characterized in that: The upper connector (200) is provided with a back nut (210) on its side wall.

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