Lifting reciprocating type oil drainage device

Abstract

The invention provides a lifting reciprocating type oil drainage device, and relates to the technical field of production equipment in the oil exploitation industry. Comprising an outer sleeve, a center pipe, an upper gland, a lower gland and an anchoring mechanism, two pin keys are arranged on the inner wall of the outer sleeve, first cavities are formed in the positions, attached to the inner wall of the outer sleeve, of the outer walls of the pin keys, and first springs are arranged at the two ends of one side of the inner wall of each first cavity; the other end of the first spring is connected to the inner wall of a first cavity formed in one side of the pin key, a first oil drainage hole and a second oil drainage hole are formed in the bottom end of the outer sleeve and the bottom end of the center pipe respectively, the first oil drainage hole and the second oil drainage hole are arranged to be in a cone shape with the large inside and the small outside, and spiral grooves are formed in the inner wall of the first oil drainage hole and the inner wall of the second oil drainage hole respectively. The device is reasonable in structure, easy to operate, high in reliability and capable of being suitable for highly-deviated wells and horizontal well oil pipe oil drainage devices, and therefore the adaptability and reliability of the device are effectively improved.

Description

Technical Field

[0001] This invention relates to the field of production equipment technology in the oil extraction industry, specifically to a lifting and lowering reciprocating oil drainer. Background Technology

[0002] Waste fluids generated during oilfield downhole operations can easily pollute the well site environment if not promptly recovered and treated, and subsequent treatment is costly and difficult. Oil drainers effectively prevent crude oil, wastewater, and other liquids from being carried to the surface, thus avoiding environmental pollution, and also reduce the impact of blowouts on the construction progress.

[0003] Existing oil drainers mainly rely on external force to drain oil, such as hydraulic oil drainers, lift oil drainers, impact oil drainers, and rotary oil drainers. The main problems with commonly used oil drainers are their complex structure and operation, poor reliability, difficulty in operation in ultra-deep wells with large inclinations, high risk of injury, and inability to be reused after opening, resulting in resource waste.

[0004] Therefore, those skilled in the art have provided a lifting and lowering reciprocating oil drainer to solve the problems mentioned in the background art. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a reciprocating oil drainer with a reasonable structure, simple operation, and high reliability. It is applicable to oil drainers in tubing of highly deviated wells and horizontal wells, thereby effectively improving the adaptability and reliability of the device. It solves the main problems of commonly used oil drainers, such as complex structure and operation, poor reliability, high difficulty in operation and risk of injury in ultra-deep, highly deviated wells, and the inability to reuse the device after opening, resulting in resource waste.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A reciprocating oil drainer includes an outer tube, a central tube, an upper pressure cap, a lower pressure cap, and an anchoring mechanism. The inner wall of the outer tube is provided with two pins. A first cavity is opened at the position where the outer wall of the pins fits against the inner wall of the outer tube. A first spring is provided at both ends of one side of the inner wall of the first cavity. The other end of the first spring is connected to the inner wall of the first cavity opened on one side of the pins. Through the above technical solution, the cooperation between the first spring and the key makes the key and the central tube fit more tightly, thus improving the reliability of locking.

[0007] Furthermore, the outer sleeve and the central tube are respectively provided with a first oil drain hole and a second oil drain hole at their bottom ends. The first oil drain hole and the second oil drain hole are set as cones with a larger inner diameter and a smaller outer diameter. The inner walls of the first oil drain hole and the second oil drain hole are provided with spiral grooves. The spiral direction inside the spiral groove is consistent with the rotation direction of the central tube. Through the above technical solutions, the conical orifice reduces the flow resistance of heavy oil, and the spiral guide groove makes the crude oil form a spiral flow, using centrifugal force to throw away sand particles, thus achieving self-cleaning and anti-clogging.

[0008] Furthermore, the outer wall of the upper end of the central tube is provided with a second serrated conical surface, and two short track grooves and a first long track groove are provided on the outer wall of the upper end of the central tube at the lower end of the second serrated conical surface. The short track grooves and the first long track groove mesh with the pin key. The above technical solution, in conjunction with the central pipe, facilitates oil drainage.

[0009] Furthermore, the lower outer wall of the anchoring mechanism is provided with a first sawtooth cone surface, and the lower outer wall of the bottom of the anchoring mechanism and located at the lower end of the first sawtooth cone surface are provided with two short track grooves and a second long track groove. The above technical solution, in conjunction with the locking mechanism, secures the oil drainer.

[0010] Furthermore, the upper outer wall of the anchoring mechanism is provided with a locking mechanism, the lower outer wall of the locking mechanism is provided with four friction blocks, and the upper outer wall of the locking mechanism is provided with four anchor teeth; The above technical solution uses a locking mechanism that mechanically locks the oil drainer to the inner wall of the casing, thus fixing its relative position downhole and ensuring a stable seal and reliable oil draining operation.

[0011] Furthermore, the upper and lower pressure caps form a closed annular cavity. Both the upper and lower pressure caps have threads at their ends. The upper pressure cap is connected to the tubing inside the well, and the lower pressure cap is connected to the pump and other tools. The external threads of the upper and lower pressure caps are respectively connected to the internal threads at the upper and lower ends of the outer sleeve. The outer sleeve is an outer tube fitted outside the central tube. The surface roughness of the inner wall of the outer sleeve and the outer wall of the central tube has certain requirements. The central tube can slide up and down in the annular cavity of the outer sleeve. When the pin of the outer sleeve is in the short track groove of the central tube, the first drain hole cannot be connected to the second drain hole due to the distance and angle difference. When the pin of the outer sleeve is in the first long track groove of the central tube, the first and second drain holes coincide and are connected. The anchoring mechanism is threadedly connected to the central tube. The above technical solution utilizes the upper and lower pressure caps and outer sleeve to form a closed annular cavity, and with the sliding and meshing structure of the central tube, the connection and sealing conversion of the oil drain hole can be realized, thus meeting the basic functional requirements of downhole oil draining operations.

[0012] This invention provides a reciprocating oil drainer. It has the following advantages: 1. This invention provides a reciprocating oil drainer that uses a combination structure of a conical drain hole, a spiral guide groove and a stainless steel filter screen to achieve triple anti-clogging function, which greatly reduces the probability of clogging in sand-containing wells and extra-heavy oil wells, thereby improving the practicality of the device. Furthermore, through the mutual cooperation between the first spring and the pin, the pin and the central tube can fit more tightly, improving the reliability of locking.

[0013] 2. This invention provides a reciprocating oil drainer that can slide relative to the central tube and the outer tube in an annular cavity. When the oil drainer of this invention is used in environments such as highly deviated wells, horizontal wells, extra-heavy oil wells, and high-pour-point oil wells where oil draining operations are required, simply lift the tubing string to make the first and second drain holes overlap and connect, and then the liquid in the tubing string is drained into the annulus through the drain holes to achieve oil draining, ensuring clean construction and protecting the well site environment. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the upper pressure cap structure of the present invention; Figure 2 This is a schematic diagram of the lower pressure cap structure of the present invention; Figure 3 This is a schematic diagram of the outer tube structure of the present invention; Figure 4 This is a schematic diagram of the central tube structure of the present invention; Figure 5 This is a schematic diagram of the anchoring mechanism of the present invention; Figure 6 This is a schematic diagram of the anchor tooth shrinkage state of the present invention; Figure 7 This is a schematic diagram of the track groove structure of the present invention; Figure 8 This is a view of the track unfolded according to the present invention; Figure 9 This is a view of the track gear position of the present invention; Figure 10 This is a schematic diagram of the unused sealed state of the present invention; Figure 11 This is a schematic diagram of the well-anchored sealing state according to the present invention; Figure 12 This is a schematic diagram of the oil draining state of the present invention; Figure 13 This is a cross-sectional view of the central tube of the present invention; Figure 14 For the present invention Figure 13 Enlarged view of point A in the middle; Figure 15 For the present invention Figure 13 Enlarged view of point B in the middle.

[0015] Explanation of reference numerals in the attached figures: 1. Pin; 101. First cavity; 102. First spring; 2. First oil drain hole; 201. Spiral groove; 3. Second oil drain hole; 4. Short track groove; 5. First long track groove; 6. Anchor tooth; 7. Friction block; 8. Locking mechanism; 9. First serrated cone surface; 10. Second serrated cone surface; 11. Second long track groove. Detailed Implementation

[0016] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0017] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0018] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0019] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0020] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0021] like Figures 1-15As shown, this embodiment of the invention provides a reciprocating oil drain device, including an outer tube, a central tube, an upper pressure cap, a lower pressure cap, and an anchoring mechanism. Two pins 1 are provided on the inner wall of the outer tube. A first cavity 101 is provided at the position where the outer wall of the pin 1 fits against the inner wall of the outer tube. A first spring 102 is provided at both ends of one side of the inner wall of the first cavity 101. The other end of the first spring 102 is connected to the inner wall of the first cavity 101 on one side of the pin 1. Through the mutual cooperation between the first spring 102 and the pin 1, the pin 1 and the central tube fit more tightly, improving the reliability of locking.

[0022] The outer sleeve and the center tube are respectively provided with a first oil drain hole 2 and a second oil drain hole 3 at their bottom ends. The first oil drain hole 2 and the second oil drain hole 3 are set as cones with a larger inner diameter and a smaller outer diameter. The inner walls of the first oil drain hole 2 and the second oil drain hole 3 are provided with spiral grooves 201. The spiral direction inside the spiral grooves 201 is consistent with the rotation direction of the center tube. The conical holes reduce the flow resistance of heavy oil, and the spiral guide grooves make the crude oil form a spiral flow. The centrifugal force is used to throw away sand particles to achieve self-cleaning and anti-clogging.

[0023] The upper outer wall of the central tube is provided with a second serrated conical surface 10. Two short track grooves 4 and a first long track groove 5 are provided on the upper outer wall of the central tube and at the lower end of the second serrated conical surface 10. The short track grooves 4 and the first long track groove 5 are engaged with the pin key 1 and cooperate with the central tube to facilitate oil drainage.

[0024] The lower outer wall of the anchoring mechanism is provided with a first serrated cone surface 9. The lower outer wall of the anchoring mechanism, located at the lower end of the first serrated cone surface 9, has two short track grooves 4 and a second long track groove 11, which cooperate with the locking mechanism 8 to fix the oil drainer. The upper outer wall of the anchoring mechanism is provided with a locking mechanism 8. The lower outer wall of the locking mechanism 8 is provided with four friction blocks 7, and the upper outer wall of the locking mechanism 8 is provided with four anchor teeth 6. Through the mechanical locking cooperation between the locking mechanism 8 and the inner wall of the casing, the relative position of the oil drainer downhole is fixed to ensure stable sealing and reliable oil draining operation.

[0025] The upper and lower pressure caps form a closed annular cavity. Both the upper and lower pressure caps have threads at their ends. The upper pressure cap connects to the tubing inside the well, and the lower pressure cap connects to the pump and other tools. The external threads of the upper and lower pressure caps connect to the internal threads at the upper and lower ends of the outer sleeve, respectively. The outer sleeve is an outer tube fitted outside the central tube. The surface roughness of the inner wall of the outer sleeve and the outer wall of the central tube has certain requirements. The central tube can slide up and down in the annular cavity of the outer sleeve. When the pin 1 of the outer sleeve is in the short track groove 4 of the central tube, the first drain hole 2 cannot be connected to the second drain hole 3 due to the distance and angle difference. When the pin 1 of the outer sleeve is in the first long track groove 5 of the central tube, the first and second drain holes coincide and are connected. The anchoring mechanism is threadedly connected to the central tube. By using the upper and lower pressure caps and the outer sleeve to form a closed annular cavity, and cooperating with the sliding and meshing structure of the central tube, the connection and sealing conversion of the drain holes can be realized, meeting the basic functional requirements of downhole oil drainage operations.

[0026] Working principle: Before use, connect the drain plug to the tubing and lower it into the well. The pin 1 is positioned inside the short track groove 4, at which point the drain hole is misaligned and sealed, and the anchor teeth 6 retract. Pulling up the tubing causes the friction block 7 to drive the locking mechanism 8 downwards, forcing it to switch to the bottom of the second long track groove 11. After lowering the tubing, the locking mechanism 8 moves upwards, causing the anchor teeth 6 to open and anchor the casing. The pin 1 slides to the top of the track groove, maintaining a seal. When draining is required, pull up the tubing, causing the outer casing to move upwards. The pin 1 slides into the first long track groove 5, allowing the first drain hole 2 and... The second drain hole 3 overlaps, and the mixed liquid passes through the first drain hole 2 and the second drain hole 3. The first drain hole 2 and the second drain hole 3 are formed into spiral grooves 201. Due to centrifugal force, the mixed liquid in the spiral grooves 201 throws impurities away from the hole wall, avoids impurity accumulation, improves the oil draining efficiency, and is filtered through the filter screen 205. At this time, the anchoring is released. When it is necessary to close the oil drain, the pin 1 is returned to the short track groove 4 by lifting and lowering the tube column. At the same time, the anchor tooth 6 is contracted, and the first drain hole 2 and the second drain hole 3 are misaligned again, thereby restoring the seal.

[0027] The following points should be noted in this article: 1. The accompanying drawings of the embodiments disclosed herein only relate to the structures involved in the embodiments disclosed herein; other structures can be referred to in general design.

[0028] 2. Where there is no conflict, the embodiments of this disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0029] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A reciprocating oil drain device, comprising an outer sleeve, a central sleeve, an upper pressure cap, a lower pressure cap, and an anchoring mechanism, characterized in that: The inner wall of the outer tube is provided with two pins (1). The outer wall of the pins (1) and the position where they fit against the inner wall of the outer tube are provided with a first cavity (101). The two ends of the inner wall of the first cavity (101) are provided with a first spring (102). The other end of the first spring (102) is connected to the inner wall of the first cavity (101) opened on one side of the pins (1).

2. The reciprocating oil drainer according to claim 1, characterized in that: The outer sleeve and the center tube are respectively provided with a first oil drain hole (2) and a second oil drain hole (3). The first oil drain hole (2) and the second oil drain hole (3) are set as a cone shape with a larger inner diameter and a smaller outer diameter. The inner walls of the first oil drain hole (2) and the second oil drain hole (3) are provided with spiral grooves (201). The spiral direction inside the spiral grooves (201) is consistent with the rotation direction of the center tube.

3. The lifting and lowering reciprocating oil drain device according to claim 1, characterized in that: The upper outer wall of the central tube is provided with a second sawtooth cone surface (10). The upper outer wall of the central tube and the lower end of the second sawtooth cone surface (10) are provided with two short track grooves (4) and a first long track groove (5). The short track grooves (4) and the first long track groove (5) mesh with the pin (1).

4. The reciprocating oil drain device according to claim 1, characterized in that: The lower outer wall of the anchoring mechanism is provided with a first sawtooth cone surface (9), and the lower outer wall of the anchoring mechanism and located at the lower end of the first sawtooth cone surface (9) has two short track grooves (4) and a second long track groove (11).

5. The lifting and lowering reciprocating oil drainer according to claim 1, characterized in that: The upper outer wall of the anchoring mechanism is provided with a locking mechanism (8), the lower outer wall of the locking mechanism (8) is provided with four friction blocks (7), and the upper outer wall of the locking mechanism (8) is provided with four anchor teeth (6).

6. The lifting and lowering reciprocating oil drainer according to claim 3, characterized in that: The upper and lower pressure caps form a closed annular cavity. Both the upper and lower pressure caps are threaded at their ends. The upper pressure cap is connected to the tubing inside the well, and the lower pressure cap is connected to the pump and other tools. The external threads of the upper and lower pressure caps are respectively connected to the internal threads of the upper and lower ends of the outer sleeve. The outer sleeve is an outer tube fitted outside the central tube. The surface roughness of the inner wall of the outer sleeve and the outer wall of the central tube has certain requirements. The central tube can slide up and down in the annular cavity of the outer sleeve. When the pin (1) of the outer sleeve is in the short track groove (4) of the central tube, the first drain hole (2) has a distance and angle difference and cannot be connected to the second drain hole (3). When the pin (1) of the outer sleeve is in the first long track groove (5) of the central tube, the first and second drain holes coincide and are connected. The anchoring mechanism is threadedly connected to the central tube.

Images