A plunger with a rotating function and a method thereof

Abstract

This invention belongs to the technical field of gas field extraction equipment, specifically relating to a rotary plunger and its method. The invention includes a retrieval head, a guide rod, and a plunger housing. The top of the guide rod is connected to the retrieval head, and a first flow channel is axially formed at the center of the bottom end of the guide rod. Multiple lateral flow channels are formed in the middle of the sidewall of the guide rod, and the first flow channel communicates with the multiple lateral flow channels. The plunger housing is connected to the bottom end of the guide rod, and a second flow channel is axially formed at the center of the plunger housing, communicating with the lateral flow channels through the first flow channel. This invention achieves the purpose of gas lift and liquid discharge using a rotary plunger, effectively improving the efficiency of the plunger's liquid lift. Simultaneously, the design of the retrieval head effectively prevents incorrect placement during the construction process.

Description

Technical Field

[0001] This invention belongs to the technical field of gas field extraction equipment, specifically relating to a plunger with a rotating function and a method thereof. Background Technology

[0002] Plunger gas lift is a drainage and gas production technology that utilizes the well's own energy to expel liquid from the wellbore. This technology uses a plunger as a mechanical interface between gas and liquid. Gas produced from the well propels the plunger in a periodic up-and-down motion within the tubing, periodically lifting the formation liquid to the surface and producing gas. As the gas-liquid interface, the plunger effectively prevents gas from escaping and liquid from falling back, reducing the "slippage" effect as liquid travels from the wellbore to the wellhead and improving the efficiency of gas-liquid lifting. This is a mechanical drainage and gas production method that relies entirely on the well's own energy during the drainage process, without the addition of any chemical agents or external energy. It is suitable for wells with a certain production capacity and a daily water production of less than 40 m³. 3 Gas lift technology has been widely applied in tight, low-yield gas fields worldwide with good results. Currently, when a plunger lifts liquid in the wellbore, the gap between the plunger and the tubing results in significant liquid loss during the upward movement of a conventional plunger, which affects the efficiency of gas-lifted liquid to some extent. With the widespread adoption of plunger gas lift technology, theoretical research has shown that liquid leakage decreases with increasing rotational speed. Through numerical simulation and continuous experimentation to improve the plunger structure, a plunger with rotational function has been developed. This plunger can rotate on its own, thereby reducing liquid loss and improving the plunger's liquid lifting efficiency. Summary of the Invention

[0003] This invention provides a plunger with a rotating function and a method thereof, the purpose of which is to provide a plunger that can improve the liquid lifting efficiency of the plunger and prevent the incorrect placement of the plunger during construction.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A rotary plunger, comprising:

[0006] Salvage head;

[0007] The guide rod is connected to the retrieval head at its top. A first flow channel is opened axially at the center of the bottom end of the guide rod. Multiple lateral flow channels are opened in the middle of the side wall of the guide rod. The first flow channel is connected to the multiple lateral flow channels.

[0008] The plunger housing is connected to the bottom end of the guide rod. A second flow channel is provided axially at the center of the plunger housing. The second flow channel is connected to the lateral flow channel through the first flow channel.

[0009] The outer wall of the plunger housing is provided with multiple fishbone-shaped annular protrusions spaced circumferentially.

[0010] The fishbone-shaped annular protrusions are evenly spaced.

[0011] The multiple lateral flow channels are arranged in a circular array around the center of the guide rod, and the outer outlet centers of the lateral flow channels are placed on the same horizontal circular surface.

[0012] The lateral flow channel is a spiral channel, and the line connecting the center of the inlet of the spiral channel with the center of the guide rod and the line connecting the center of the outlet of the spiral channel with the center of the guide rod form an angle θ.

[0013] The second flow channel and the first flow channel have the same inner diameter.

[0014] A method for using a plunger with a rotating function, characterized by the following steps:

[0015] Step 1: Plunger connection;

[0016] Connect the salvage head, guide rod, and plunger housing from top to bottom;

[0017] Step 2: Plunger deployment;

[0018] The limiter is deployed to a location in the well by logging truck, or by deploying a plunger with a rotating function using an existing limiter in the gas well. After shutting down the well, the plunger with the rotating function falls down above the limiter by its own weight.

[0019] Step 3: Plunger production;

[0020] After well opening, the bottom gas pushes the rotating plunger and the liquid above it upwards. The bottom gas enters the second guide channel inside the plunger housing and is discharged through the lateral guide channel inside the guide rod. When the bottom gas is discharged through the spirally arranged lateral guide channel, it causes the rotating plunger to rotate. The rotating plunger rotates and rises, and after reaching the wellhead, the liquid is discharged. The rotating plunger then enters the blowout preventer. After production is completed, the well is shut in, and the rotating plunger moves downwards again under its own weight, falling above the limit switch. The entire production cycle repeats this process.

[0021] Step 4: Plunger retrieval;

[0022] When the rotating plunger can reach the wellhead, the plunger catcher on the blowout preventer is opened, the rotating plunger is caught at the wellhead, the blowout preventer is opened, and the rotating plunger is taken out; when the plunger cannot reach the wellhead, the fishing tool grabs the plunger fishing head through wireline operation and fishes the rotating plunger out of the wellbore.

[0023] In step three, the piston rotation speed ω is correlated with the rotational driving force F and the included angle θ, as detailed below:

[0024] v =219.96Δp 0.59 - v 柱塞

[0025]

[0026]

[0027]

[0028] Where: ΔP is the pressure difference between the upper and lower parts of the plunger, ΔP≤0.1 MPa;

[0029] v 柱塞 The upward speed of the plunger. v 柱塞 ≤10 m / s;

[0030] v The ambient air velocity is 10 m / s;

[0031] n represents the number of lateral flow channels;

[0032] ρ is the fluid density passing through the plunger, in kg / m³. 3 ;

[0033] δ is the width of the second guide channel, in mm;

[0034] L is the length from the outlet of the lateral flow channel to the bottom of the plunger, in mm.

[0035] Beneficial effects:

[0036] (1) The present invention is organically combined with a retrieval head, a guide rod and a plunger housing. Due to the setting of multiple inclined lateral flow channels inside the guide rod, the present invention achieves the purpose of rotating plunger air lift liquid discharge, which greatly improves the efficiency of plunger liquid lift.

[0037] (2) The design of the retrieval head in this invention effectively prevents the plunger from being placed incorrectly during construction.

[0038] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a schematic diagram of the structure of the present invention.

[0041] Figure 2 This is a cross-sectional view of the flow guiding channel in this invention.

[0042] In the diagram: 1. Salvage head; 2. Lateral flow channel; 3. Guide rod; 4. Second flow channel; 5. Plunger housing; 6. Fishbone-shaped annular protrusion; 7. First flow channel. Detailed Implementation

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0044] Example 1:

[0045] according to Figure 1 and Figure 2 The illustrated plunger with a rotating function includes

[0046] Salvage head 1;

[0047] The guide rod 3 is connected to the top of the retrieval head 1. The center of the bottom end of the guide rod 3 has a first flow channel 7 along the axial direction. The middle of the side wall of the guide rod 3 has multiple lateral flow channels 2. The first flow channel 7 is connected to the multiple lateral flow channels 2.

[0048] The plunger housing 5 is connected to the bottom end of the guide rod 3. The center of the plunger housing 5 is provided with a second flow channel 4 along the axial direction. The second flow channel 4 is connected to the lateral flow channel 2 through the first flow channel 7.

[0049] In actual use, the retrieval head 1, guide rod 3, and plunger housing 5 are first connected sequentially from top to bottom. Then, a limiter is deployed to a predetermined position in the well using a logging truck, or an existing limiter in the gas well is used to deploy the rotating plunger. After shutting down the well, the rotating plunger falls downwards under its own weight above the limiter. After well opening, the bottomhole gas pushes the rotating plunger and the liquid above it upwards. The bottomhole gas sequentially enters the second guide channel 4 inside the plunger housing 5 and exits through the lateral guide channel 2 inside the guide rod 3. As the bottomhole gas exits through the inclined lateral guide channel 2, it causes the rotating plunger to rotate. The rotating plunger rotates and rises, reaching the wellhead where the liquid is discharged, and then the rotating plunger reaches the blowout preventer. After production is completed, the well is shut down, and the rotating plunger again moves downwards under its own weight, falling above the limiter. This process is repeated for the entire production cycle. When the rotating plunger can reach the wellhead, the plunger catcher on the blowout preventer is opened, and the rotating plunger is captured. The blowout preventer is then opened, and the rotating plunger is retrieved. When the plunger cannot reach the wellhead, a wireline retrieval tool is used to grab the plunger retrieval head 1 and retrieve the rotating plunger out of the wellbore.

[0050] This invention achieves the purpose of rotary plunger air lift liquid discharge, thereby reducing liquid loss and effectively improving the efficiency of plunger liquid lift. At the same time, the design of the retrieval head effectively prevents incorrect placement during construction.

[0051] Example 2:

[0052] according to Figure 1 The plunger shown has a rotating function, which differs from Embodiment 1 in that: the outer wall of the plunger housing 5 is provided with multiple fishbone-shaped annular protrusions 6 spaced circumferentially.

[0053] Furthermore, the fishbone-shaped annular protrusions 6 are evenly spaced.

[0054] In practical use, the plunger housing 5 adopts a technical solution of setting multiple fishbone-shaped annular protrusions 6 at intervals along the circumference on the outer side wall. On the one hand, when the plunger moves up and down, a turbulent seal is formed, which can reduce liquid leakage and help improve the liquid lifting efficiency of the plunger. On the other hand, the fishbone-shaped annular protrusions 6 have the characteristics of strong passability, easy processing and easy capture.

[0055] Example 3:

[0056] according to Figure 1 and Figure 2 The plunger shown has a rotating function, which differs from Embodiment 1 in that: the multiple lateral flow channels 2 are arranged in a circular array around the center of the guide rod 3, and the outer outlet center of the lateral flow channels 2 is placed on the same horizontal circular surface.

[0057] In practical use, the side flow channel 2 adopts the above technical solution, which makes the plunger rotate faster when the liquid is discharged from the side flow channel 2, thus enhancing the liquid lifting efficiency of the plunger.

[0058] Example 4:

[0059] according to Figure 1 and Figure 2 The plunger shown has a rotating function, which differs from Embodiment 3 in that the lateral flow channel 2 is a spiral channel, and the line connecting the inlet center of the spiral channel with the center of the guide rod 3 and the line connecting the outlet center with the center of the guide rod 3 form an angle θ.

[0060] In actual use, the lateral flow channel 2 adopts a spiral channel in order to make the plunger rotate faster when the liquid is discharged from the lateral flow channel 2, so as to enhance the liquid lifting efficiency of the plunger.

[0061] Example 5:

[0062] according to Figure 1 The plunger shown has a rotating function, which differs from Embodiment 1 in that the inner diameters of the second flow channel 4 and the first flow channel 7 are the same.

[0063] In practical use, the second guide channel 4 and the first guide channel 7 adopt the above technical solution. The purpose is to ensure that the airflow is unobstructed when passing through the second guide channel 4 and the first guide channel 7, so that when the fluid is discharged from the lateral guide channel 2, the plunger rotates faster, thereby enhancing the liquid lifting efficiency of the plunger.

[0064] Example 6:

[0065] according to Figure 1 and Figure 2 The plunger shown has a rotating function, which differs from Embodiment 1 in that: multiple fishbone-shaped annular protrusions 6 are arranged circumferentially on the outer wall of the plunger housing 5; the fishbone-shaped annular protrusions 6 are evenly spaced; multiple lateral flow channels 2 are arranged in a circular array around the center of the guide rod 3, and the outer outlet centers of the lateral flow channels 2 are placed on the same horizontal circular surface; the lateral flow channels 2 are spiral channels, and the line connecting the inlet center of the spiral channel with the center of the guide rod 3 and the line connecting the outlet center with the center of the guide rod 3 form an angle θ; the inner diameters of the second flow channel 4 and the first flow channel 7 are the same.

[0066] The technical solution of this invention achieves the purpose of rotary plunger air lift liquid discharge, effectively improving the efficiency of plunger liquid lift. At the same time, the design of the retrieval head effectively prevents incorrect placement during construction.

[0067] Example 7:

[0068] Reference Figure 1 and Figure 2 As shown, a method for using a plunger with a rotating function includes the following steps:

[0069] Step 1: Plunger connection;

[0070] Connect the salvage head 1, guide rod 3 and plunger housing 5 from top to bottom in sequence;

[0071] Step 2: Plunger deployment;

[0072] The limiter is deployed to a location in the well by logging truck, or by deploying a plunger with a rotating function using an existing limiter in the gas well. After shutting down the well, the plunger with the rotating function falls down above the limiter by its own weight.

[0073] Step 3: Plunger production;

[0074] After well opening, the bottom gas pushes the rotating plunger and the liquid above it upward. The bottom gas enters the second guide channel 4 inside the plunger housing 5 and is discharged through the lateral guide channel 2 inside the guide rod 3. When the bottom gas is discharged through the inclined lateral guide channel 2, it causes the rotating plunger to rotate. The rotating plunger rotates and rises, and after reaching the wellhead, the liquid is discharged. The rotating plunger then enters the blowout preventer. After production is completed, the well is shut in, and the rotating plunger moves downward again under its own weight, falling above the limit switch. The entire production cycle repeats this process.

[0075] Step 4: Plunger retrieval;

[0076] When the rotating plunger can reach the wellhead, the plunger catcher on the blowout preventer is opened, the rotating plunger is caught at the wellhead, the blowout preventer is opened, and the rotating plunger is taken out; when the plunger cannot reach the wellhead, the fishing tool grabs the plunger fishing head 1 through wireline operation and fishes the rotating plunger out of the wellbore.

[0077] This invention enables the plunger to rotate independently, thereby reducing liquid leakage and effectively improving the plunger's liquid lifting efficiency. The self-rotating plunger design, along with the retrieval head design, prevents errors in placement during construction.

[0078] Example 8:

[0079] Reference Figure 1 and Figure 2As shown, a method of using a plunger with a rotating function differs from Embodiment 7 in that: in step three, the plunger's rotational speed ω is correlated with the rotational driving force F and the included angle θ, as detailed below:

[0080] v =219.96Δp 0.59 - v 柱塞

[0081]

[0082]

[0083]

[0084] Where: ΔP is the pressure difference between the upper and lower parts of the plunger, ΔP≤0.1 MPa;

[0085] v 柱塞 The upward speed of the plunger. v 柱塞 ≤10 m / s;

[0086] v The ambient air velocity is 10 m / s;

[0087] n represents the number of lateral flow channels;

[0088] ρ is the fluid density passing through the plunger, in kg / m³. 3 ;

[0089] δ is the width of the second guide channel, in mm;

[0090] L is the length from the outlet of the lateral flow channel to the bottom of the plunger, in mm.

[0091] The lateral flow channel is made into a spiral shape, which allows the airflow to impact the plunger and generate rotation, thereby achieving the purpose of rotating the plunger to lift and discharge liquid, greatly improving the efficiency of the plunger to lift liquid.

[0092] Where there is no conflict, those skilled in the art can combine the relevant technical features in the above examples according to the actual situation to achieve the corresponding technical effects. Specific details of the various combinations will not be elaborated here.

[0093] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0094] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0095] The above description is merely a preferred embodiment of the present invention. The present invention is not limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. Any simple modifications, equivalent variations, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the present invention.

Claims

1. A method of using a plunger with a rotating function, characterized in that: The plunger used has a rotating function, including Salvage head (1); The guide rod (3) is connected to the top of the retrieval head (1). The center of the bottom end of the guide rod (3) has a first flow channel (7) along the axial direction. The middle of the side wall of the guide rod (3) has multiple lateral flow channels (2). The first flow channel (7) is connected to the multiple lateral flow channels (2). The plunger housing (5) is connected to the bottom end of the guide rod (3). The center of the plunger housing (5) is provided with a second flow channel (4) along the axial direction. The second flow channel (4) is connected to the lateral flow channel (2) through the first flow channel (7). Includes the following steps: Step 1: Plunger connection; Connect the salvage head (1), guide rod (3) and plunger housing (5) from top to bottom; Step 2: Plunger deployment; The limiter is deployed to a location in the well by logging truck, or by deploying a plunger with a rotating function using an existing limiter in the gas well. After shutting down the well, the plunger with the rotating function falls down above the limiter by its own weight. Step 3: Plunger production; After the well is opened, the bottom gas pushes the rotating plunger and the liquid above it to move upward. The bottom gas enters the second guide channel (4) inside the plunger housing (5) in sequence and is discharged through the lateral guide channel (2) inside the guide rod (3). When the bottom gas is discharged through the spirally arranged lateral guide channel (2), it causes the rotating plunger to rotate. The rotating plunger rotates and rises, and after reaching the wellhead, the liquid is discharged. The rotating plunger reaches the blowout preventer. After production is completed, the well is shut in, and the rotating plunger moves downward again under its own weight and falls above the limit switch, completing the entire production cycle. Step 4: Plunger retrieval; When the rotating plunger reaches the wellhead, the plunger is captured by opening the plunger catcher on the blowout preventer. The blowout preventer is then opened and the rotating plunger is removed. When the plunger cannot reach the wellhead, a wireline retrieval tool grabs the plunger retrieval head and retrieves the rotating plunger out of the wellbore. In step three, the piston rotation speed ω is correlated with the rotational driving force F and the included angle θ, as detailed below: v =219.96Δp 0.59 - v 柱塞 Where: ΔP is the pressure difference between the upper and lower parts of the plunger, ΔP≤0.1MPa; v 柱塞 The upward speed of the plunger. v 柱塞 ≤10 m / s; v The ambient air velocity is 10 m / s; n represents the number of lateral flow channels; ρ is the fluid density passing through the plunger, in kg / m³. 3 ; δ is the width of the second guide channel, in mm; L is the length from the outlet of the lateral flow channel to the bottom of the plunger, in mm.

2. The method of using a plunger with a rotating function as described in claim 1, characterized in that: The outer wall of the plunger housing (5) is provided with multiple fishbone-shaped annular protrusions (6) spaced circumferentially.

3. The method of using a plunger with a rotating function as described in claim 2, characterized in that: The fishbone-shaped annular protrusions (6) are evenly spaced.

4. The method of using a plunger with a rotating function as described in claim 1, characterized in that: Multiple lateral flow channels (2) are arranged in a circular array around the center of the guide rod (3), and the outer outlet center of the lateral flow channels (2) is placed on the same horizontal circular surface.

5. The method of using a plunger with a rotating function as described in claim 4, characterized in that: The lateral flow channel (2) is a spiral channel, and the line connecting the center of the inlet of the spiral channel with the center of the guide rod (3) and the line connecting the center of the outlet with the center of the guide rod (3) form an angle θ.

6. The method of using a plunger with a rotating function as described in claim 1, characterized in that: The second guide channel (4) and the first guide channel (7) have the same inner diameter.

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