Intelligent discharging and mining system of screw pump

Abstract

The invention discloses a screw pump intelligent drainage system which comprises a sleeve, an oil pipe is inserted into the sleeve, a hollow rod is inserted into the oil pipe, the top of the hollow rod is connected with a mixed liquid source head box through a booster pump, and the hollow rod provides rotating power through a ground driving head. The tail end of the hollow rod is connected with a screw pump through a reverse check valve, a top outlet of the oil pipe is communicated with a storage tank through a pipeline, the storage tank is communicated with a booster pump through a pipeline, and a doped liquid flowmeter and a doped liquid electromagnetic valve are arranged on the pipeline at the outlet end of the booster pump. The pipeline at the inlet end of the storage tank is provided with a produced liquid flow meter, the ground driving head is provided with a frequency converter, and the frequency converter, the mixed liquid flow meter, the mixed liquid electromagnetic valve and the produced liquid flow meter are electrically connected with a controller, so that the technical problem that the screw rod is easily damaged by dry grinding due to low submergence in the prior art is solved.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas extraction technology, and in particular relates to an intelligent drainage system using a screw pump. Background Technology

[0002] As is well known, screw pumps are effective for wells with high crude oil content or high viscosity, capable of producing crude oil with viscosities up to 50,000 MPa·s and sand content up to 50%. They are also relatively insensitive to gas and generally do not experience gas lock-up. Therefore, they are frequently used in the development of heavy oil, coalbed methane, and oil and gas wells with high sand content. However, screw pump development requires a certain submersion depth (usually 150m); otherwise, the screw pump will experience dry running and be damaged.

[0003] In the mid-to-late stage development of coalbed methane and shale gas, the formation pressure is very low, and in most cases, a subsidence depth of 150m cannot be guaranteed, which leads to frequent damage to screw pumps. Summary of the Invention

[0004] The purpose of this invention is to provide an intelligent screw pump drainage system that solves the technical problem in the prior art where low submersion depth easily leads to dry grinding damage to the screw.

[0005] The technical solution adopted by this invention to solve its technical problem is: A screw pump intelligent drainage system includes: a casing, an oil pipe inserted inside the casing, a hollow rod inserted inside the oil pipe, the top of the hollow rod connected to an incorporation source tank via a booster pump, the hollow rod receiving rotational power from a ground drive head, the end of the hollow rod connected to a screw pump, the top outlet of the oil pipe connected to a storage tank via a pipeline, the storage tank connected to the booster pump via a pipeline, an incorporation flow meter and an incorporation solenoid valve installed on the pipeline at the outlet end of the booster pump, a produced fluid flow meter installed on the pipeline at the inlet end of the storage tank, a frequency converter installed on the ground drive head, and the frequency converter, incorporation flow meter, incorporation solenoid valve, and produced fluid flow meter electrically connected to a controller.

[0006] The present invention discloses an intelligent drainage system for screw pumps, wherein a torque tester is installed on the hollow rod, and the torque tester is electrically connected to the controller.

[0007] The present invention discloses an intelligent drainage system for a screw pump, wherein a hollow rod centralizer is provided between the hollow rod and the oil pipe.

[0008] The present invention discloses an intelligent drainage system for a screw pump, wherein a reverse flow valve is provided at the bottom of the hollow rod.

[0009] The present invention discloses an intelligent drainage system for a screw pump, wherein a one-way valve is provided at the inlet end of the screw pump.

[0010] The present invention discloses an intelligent drainage system for screw pumps, wherein a sand screen is provided in front of the inlet end of the screw pump.

[0011] The present invention discloses an intelligent drainage system for screw pumps, wherein a separator is provided at the inlet end of the storage tank.

[0012] The present invention discloses an intelligent drainage system for a screw pump, wherein a rotary seal is provided at the inlet end connection of the hollow rod.

[0013] The present invention discloses an intelligent drainage system for screw pumps, wherein an anchoring device is provided at the bottom of the oil pipe.

[0014] The beneficial effects of this invention are as follows: It proposes an intelligent screw pump drainage system, which can analyze the working status of the screw pump and the liquid level of the surrounding environment by setting up a flow meter and a torque tester. This allows for timely adjustment of the screw pump's operating parameters to ensure optimal operation and prevents dry grinding of the screw pump, thus avoiding damage to the pump's stator rubber. The installation of a sand screen also prevents sand blockage and clogging of the tubing, and it has a wide range of applicable submersion depths. Furthermore, by employing Internet of Things (IoT) technology and wireless signal transmission, it enables remote adjustment of operating parameters and remote control of operation. Attached Figure Description

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 This is a schematic diagram of an embodiment of the present invention. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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 some embodiments of the present invention, not all embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] like Figure 1As shown, a screw pump intelligent drainage system includes: a casing 9, an oil pipe 10 inserted inside the casing 9, a hollow rod 11 inserted inside the oil pipe 10, the top of the hollow rod 11 being connected to an incorporation source box via a booster pump 7, the hollow rod 11 being provided with rotational power by a ground drive head 6, the end of the hollow rod 11 being connected to a screw pump 14, the top outlet of the oil pipe 10 being connected to a storage tank 1 via a pipe, the storage tank 1 being connected to the booster pump 7 via a pipe, an incorporation flow meter 18 and an incorporation solenoid valve 4 being installed on the pipe at the outlet end of the booster pump 7, a produced fluid flow meter 19 being installed on the pipe at the inlet end of the storage tank 1, a frequency converter 8 being installed on the ground drive head 6, and the frequency converter 8, the incorporation flow meter 18, the incorporation solenoid valve 4, and the produced fluid flow meter 19 being electrically connected to a controller.

[0018] In a preferred embodiment of the present invention, a torque tester 5 is provided on the hollow rod 11, and the torque tester 5 is electrically connected to the controller.

[0019] In a preferred embodiment of the present invention, a hollow rod centralizer 12 is provided between the hollow rod 11 and the tubing 10. The hollow rod centralizer 12 adopts a deep groove ball bearing structure and is filled with lubricating oil. Due to pressure balance, there will be no lubricating oil leakage or well fluid flowing into the hollow rod centralizer (12). This reduces the friction in directional wells and horizontal wells and extends the service life of the hollow rod centralizer (12).

[0020] In a preferred embodiment of the present invention, a reverse flow valve 13 is provided at the bottom of the hollow rod 11. The reverse flow valve 13 has a reverse closing function, allowing liquid to be injected into the oil pipe 10 and the annulus of the hollow rod 11 through the hollow rod 11. Conversely, the extracted liquid cannot enter the hollow rod 11.

[0021] In a preferred embodiment of the present invention, a check valve 16 is provided at the inlet end of the screw pump 14. The check valve 16 serves to positively seal the tubing 10, preventing liquid from flowing into the well from the tubing 10, but allowing well fluid to flow into the tubing 10.

[0022] In a preferred embodiment of the present invention, a sand screen 17 is provided in front of the inlet end of the screw pump 14, and the sand screen tube 17 is provided to prevent coarse sand particles from entering the screw pump 14 and its tubing and causing malfunctions.

[0023] In a preferred embodiment of the present invention, a separator 2 is provided at the inlet end of the storage tank 1.

[0024] In a preferred embodiment of the present invention, a rotary seal 3 is provided at the inlet end connection of the hollow rod 11.

[0025] In a preferred embodiment of the present invention, an anchoring device 15 is provided at the bottom of the oil pipe 10. The anchoring device 15 is used to anchor the oil pipe 10 to prevent the oil pipe from reversing when the screw pump 14 stops, which would cause the pipe string to come off the tether.

[0026] Brief description of working principle: This application mainly comprises three systems: an injection system, a production system, and a control system. The injection system consists of a booster pump 7, a blending fluid flow meter 4, a blending fluid solenoid valve 18, a torque tester 5, a hollow rod 11, a hollow rod centralizer 12, a reverse flow valve 13, and a rotary seal 3. The production system consists of a sand screen pipe 17, a screw pump 14, an anchoring device 15, an oil pipe 10, a hollow rod 11, a ground drive head 6, a separator 2, a produced fluid flow meter 19, and a produced fluid solenoid valve 1. The control system consists of a frequency converter 8, signal input, signal analysis and processing software, and signal generation and reception. The frequency converter 8 has two control systems: one controls the speed of the booster pump 7, and the other controls the speed of the ground drive head 6. The two systems do not interfere with each other and can ensure independent operation. The injection fluid has two main functions: first, to ensure that the screw pump 14 always operates in the liquid and to prevent dry running, which could damage the screw pump 14; and second, to prevent the liquid from settling and burying the tubing due to insufficient flow rate.

[0027] The injected water or working fluid flows from the hollow rod 11 and the reverse check valve 13 into the annulus between the oil pipe 10 and the hollow rod 11 on the screw pump 14. The liquid drawn from the screw pump 14 does not flow into the hollow rod 11 due to the reverse closing action of the reverse check valve 13. The injected water or working fluid, however, flows freely through the reverse check valve 13 into the annulus between the oil pipe 10 and the hollow rod 11, flowing upwards with the liquid drawn from the screw pump 14 and being discharged to the surface. Gas-liquid separation is performed by the separator 2. Part of the separated liquid is supplied to the booster pump 7, and the remainder is discharged into the production pipeline or process. The torque detector 5 installed on the surface drive head 6 detects the torque of the entire well string. When the torque increases... At a certain value, it indicates that the sand and gravel in the produced fluid are below the critical flow velocity and have settled in the hollow rod 11 and tubing 10. The booster pump 7 is increased by the frequency converter 8 to bring the added water or working fluid to the critical flow velocity, carrying out the sand particles and preventing the sand particles from jamming the screw pump 14. When the torque remains unchanged, it indicates that there is little or no sand settling in the annulus of tubing 10 and hollow rod 11. The sand particles are extracted to the surface with the pumped fluid. At this time, the speed of the booster pump 7 is maintained, which is the normal working state. When the torque drops significantly, it indicates that there is a malfunction in the downhole rod string or screw pump 14. It is necessary to reduce or stop the addition of water or working fluid. At this time, an alarm indicates that there is a malfunction in the well and necessary measures need to be taken.

[0028] When the surface drive head 6 increases its rotational speed, and the difference between the produced fluid flow rate (produced fluid flow meter 19) and the injected fluid flow rate (injected fluid flow meter 4) does not increase or decrease within a certain time, it indicates that the rotational speed has reached its maximum value. It is necessary to maintain or reduce the rotational speed. At this point, the fluid level is near the inlet of the screw pump 6, ensuring the lowest possible fluid level during pumping. Conversely, when the surface drive head 6 decreases its rotational speed, and the difference between the produced fluid flow rate (produced fluid flow meter) and the injected fluid flow rate (injected fluid flow meter) decreases significantly within a certain time, it indicates that the rotational speed still has room to increase. It is necessary to increase the rotational speed to ensure the screw pump 6 operates near the fluid level. This method allows the screw pump 14 to operate in its optimal state, increasing the fluid production of the oil and gas well.

[0029] In the description of this invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, 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 invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0030] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0031] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A screw pump intelligent drainage system, characterized in that, include: A casing (9) is provided with an oil pipe (10) inserted inside the casing (9). A hollow rod (11) is inserted inside the oil pipe (10). The top of the hollow rod (11) is connected to the mixing liquid source box through a booster pump (7). The hollow rod (11) is powered by a ground drive head (6). The end of the hollow rod (11) is connected to a screw pump (14). The top outlet of the oil pipe (10) is connected to the storage tank (1) through a pipe. The storage tank (1) is connected to the booster pump (7) through a pipe. A mixing liquid flow meter (18) and a mixing liquid solenoid valve (4) are installed on the pipe at the outlet end of the booster pump (7). A produced liquid flow meter (19) is installed on the pipe at the inlet end of the storage tank (1). A frequency converter (8) is installed on the ground drive head (6). The frequency converter (8), the mixing liquid flow meter (18), the mixing liquid solenoid valve (4), and the produced liquid flow meter (19) are electrically connected to the controller.

2. The intelligent drainage system for screw pumps according to claim 1, characterized in that, A torque tester (5) is installed on the hollow rod (11), and the torque tester (5) is electrically connected to the controller.

3. The intelligent drainage system for screw pumps according to claim 2, characterized in that, A hollow rod stabilizer (12) is provided between the hollow rod (11) and the oil pipe (10).

4. The intelligent drainage system for screw pumps according to claim 2, characterized in that, A reverse flow valve (13) is provided at the bottom of the hollow rod (11).

5. The intelligent drainage system for screw pumps according to claim 2, characterized in that, The screw pump (14) is equipped with a check valve (16) at its inlet end.

6. The intelligent drainage system for screw pumps according to claim 5, characterized in that, A sand screen (17) is provided in front of the inlet end of the screw pump (14).

7. The intelligent drainage system for screw pumps according to claim 2, characterized in that, A separator (2) is provided at the inlet end of the storage tank (1).

8. The intelligent drainage system for screw pumps according to claim 2, characterized in that, A rotary seal (3) is provided at the inlet end connection of the hollow rod (11).

9. The intelligent drainage system for screw pumps according to claim 2, characterized in that, An anchoring device (15) is provided at the bottom of the oil pipe (10).

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