Wireless downhole liquid level monitoring screw pump

Abstract

The utility model discloses a wireless underground liquid level monitoring screw pump, which belongs to the technical field of screw pumps and comprises a tubular column, a stator and a rotor which are arranged in the tubular column and used in cooperation, a hollow sucker rod arranged on the upper portion of the rotor, an oil pipe arranged on the upper portion of the stator, and a liquid outlet tee joint arranged on the top surface of the tubular column. A ground driving device is arranged above the ground wellhead, a universal rotating joint is arranged at the top of a polish rod of the hollow sucker rod, the rotor is of a hollow structure, a built-in storage pressure gauge is arranged in the rotor, a lifting assembly is arranged above the built-in storage pressure gauge, and a limiting device is arranged at the bottom of the rotor. Ground liquid is injected into the bottom of the rotor and below the rotor through the interior of the hollow sucker rod, the liquid inlet end of the pump is scoured, pulverized coal at the liquid inlet and in the immediate vicinity of a wellbore is diluted, and liquid can be supplemented to the stratum; chemicals are added into the underground through the hollow sucker rod according to the stratum condition, and chemical agent scale inhibition is carried out; data can be read without moving a tubular column, and the pressure sensor can be rapidly replaced.

Description

Technical Field

[0001] The utility model relates to the technical field of screw pumps, in particular to a wireless downhole liquid level monitoring screw pump. Background Art

[0002] Conventional CBM well screw pump extraction systems generally use a test cable bundled outside the oil pipe to transmit downhole pressure sensor signals and realize real-time monitoring of downhole pressure and temperature. When the liquid level is low or the CBM concentration is high in the later stage of CBM extraction and production, and cannot meet the normal extraction and production requirements, downhole fluid replenishment is carried out through the reinjection water pipe bundled outside the oil pipe to dilute the downhole coal powder and replenish the downhole liquid, thereby realizing continuous extraction of the screw pump and preventing the screw pump from getting stuck or burning due to insufficient fluid supply or intermittent extraction.

[0003] Bundling the pressure gauge cable and reinjection water pipe on the outside of the oil pipe requires a large outer diameter of the overall pipe string, which is limited in high-angle well types such as directional wells and horizontal wells. The cable and reinjection water pipe are easily damaged during the process of lifting and lowering the pipe string. When the downhole pressure sensor fails, the entire pipe string needs to be lifted out of the well before the cable and pressure gauge can be replaced. This process is slow, costly, has a great impact on the well condition, and is prone to the risk of failure of other equipment. Utility Model Content

[0004] The utility model aims to provide a wireless downhole liquid level monitoring screw pump, which solves the problems of bundling a pressure gauge cable and a reinjection water pipe on the outside of the oil pipe, which can easily cause damage to the cable and the reinjection water pipe during the process of lifting and lowering the pipe string; when a downhole pressure sensor fails, all the pipe strings need to be lifted out of the well before the cable and the pressure gauge can be replaced. This process has the problems of slow operation speed, high operation cost, great impact on well conditions, and the risk of additional failure of other equipment.

[0005] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0006] The utility model discloses a wireless downhole liquid level monitoring screw pump, comprising a pipe column, wherein a stator and a rotor for use together are arranged in the pipe column, a hollow sucker rod is arranged on the upper part of the rotor, an oil pipe is arranged on the upper part of the stator, a liquid outlet tee is arranged on the top surface of the pipe column, a ground driving device for driving the hollow sucker rod is arranged above the ground wellhead, a universal rotating joint is arranged on the top of the bare rod of the hollow sucker rod, the rotor is arranged as a hollow structure, a built-in storage pressure gauge is arranged in the rotor, a lifting assembly is arranged above the built-in storage pressure gauge, and a limiting device for limiting the monitoring device is arranged at the bottom of the rotor.

[0007] Furthermore, the lifting assembly includes a second connecting member, which is arranged on the top of the built-in storage pressure gauge, and a first connecting member for docking with the second connecting member is arranged above the second connecting member, and a steel wire rope is arranged above the first connecting member.

[0008] Furthermore, it also includes a ground water vapor separation tank, a liquid re-injection pipe is provided on one side of the ground water vapor separation tank, the liquid re-injection pipe is connected to the universal rotating joint, an exhaust pipe is provided on the other side of the ground water vapor separation tank, a liquid inlet pipe and an overflow pipe are provided on the top surface of the ground water vapor separation tank, the liquid inlet pipe is connected to the liquid outlet tee, and a sewage pipe is provided on the bottom surface of the ground water vapor separation tank.

[0009] Furthermore, valves and pressure gauges are installed on the liquid reinjection pipe, the liquid inlet pipe and the exhaust pipe.

[0010] Furthermore, a sewage valve is installed on the sewage pipe.

[0011] Furthermore, the ground water-gas separation tank includes a tank body, and a plurality of first liquid-passing partitions and second liquid-passing partitions are staggeredly connected inside the tank body, the top surface of the first liquid-passing partition is flush with the top surface of the tank body, a first liquid-passing channel is arranged below the first liquid-passing partition, the bottom surface of the second liquid-passing partition is flush with the bottom surface of the tank body, a second liquid-passing channel is arranged above the second liquid-passing partition, and a third liquid-passing partition is also connected to the inside of the tank body near the left side wall, and filter cotton is installed in the top interlayer of the third liquid-passing partition.

[0012] Compared with the prior art, the beneficial technical effects of the utility model are:

[0013] The utility model can inject ground liquid into the bottom of the rotor and below through the hollow sucker rod, flush the pump inlet end, dilute the coal powder at the inlet and near the wellbore, and replenish the formation at the same time; according to the formation conditions, the hollow sucker rod can be used to add chemicals to the well to achieve chemical scale prevention and other functions; when it is necessary to read the data of the built-in storage pressure gauge, the built-in storage pressure gauge can be quickly lifted to the ground for data reading, and the data can be read without moving the pipe column; when the pressure gauge fails and needs to be inspected and repaired, the pressure sensor can also be quickly replaced without moving the pipe column. The utility model can realize multiple functions such as continuous injection of liquid, addition of chemicals, and real-time downhole data monitoring in the annulus of the sucker rod without stopping the screw pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The utility model will be further described below in conjunction with the accompanying drawings.

[0015] Figure 1This is a schematic diagram of the structure of the wireless downhole liquid level monitoring screw pump of the utility model;

[0016] Figure 2 This is an enlarged view of point A of the utility model;

[0017] Figure 3 It is an enlarged view of point B of the utility model;

[0018] Figure 4 This is an enlarged view of the C portion of the utility model;

[0019] Figure 5 It is a top view of the limiting device of the utility model;

[0020] Figure 6 It is a schematic diagram of the internal structure of the ground water-gas separation tank of the utility model.

[0021] Explanation of the accompanying drawings: 1. Ground drive device; 2. Universal rotary joint; 3. Stator; 4. Rotor; 5. Hollow sucker rod; 6. Wire rope; 7. First connecting piece; 8. Second connecting piece; 9. Built-in storage pressure gauge; 10. Limit device; 11. Pipe column; 12. Liquid outlet tee; 13. Ground water-gas separation tank; 13-1. Tank body; 13-2. First liquid partition; 13-3. Second liquid partition; 13-4. Third liquid partition; 13-5. Filter cotton; 14. Liquid reinjection pipe; 15. Liquid inlet pipe; 16. Overflow pipe; 17. Exhaust pipe; 18. Drain pipe; 19. Valve; 20. Pressure gauge; 21. Drain valve; 22. Oil pipe. DETAILED DESCRIPTION

[0022] like Figure 1-6 As shown, a wireless downhole liquid level monitoring screw pump comprises a stator 3 and a rotor 4 used together, the top surface of the rotor 4 is connected with a hollow sucker rod 5, the outer side of the stator 3 is provided with a pipe string 11, the top surface of the pipe string 11 is connected with a liquid outlet tee 12, a ground driving device 1 for driving the hollow sucker rod 5 is installed above the liquid outlet tee 12, a universal rotary joint 2 is installed on the hollow sucker rod 5 above the ground driving device 1, the rotor 4 is set as a hollow structure, a monitoring device is arranged in the hollow sucker rod 5, the monitoring device extends to the bottom of the rotor 4 after passing through the hollow sucker rod 5, and a limiting device 10 for limiting the monitoring device is installed at the bottom of the rotor 4; specifically, the ground driving device is a power device, that is, a three-phase asynchronous motor drives a reduction box to drive the downhole screw pump to rotate, and the ground driving device uses a commonly used driver, model ZHD-30.

[0023] like Figure 2As shown, the monitoring device includes a built-in storage pressure gauge 9, the top of which is connected to a second connecting piece 8, a first connecting piece 7 for docking with the second connecting piece 8 is arranged above the second connecting piece 8, and a wire rope 6 is connected above the first connecting piece 7; specifically, the first connecting piece 7 and the second connecting piece 8 are both hooks; the built-in storage pressure gauge 9 is a purchased part, and its specific structure, working principle and usage are all existing technologies, which are not repeated here; the built-in storage pressure gauge 9 has a battery inside, which can monitor the pressure and temperature downhole in real time; when it is necessary to view the downhole monitoring data, the wire rope 6 is lowered through the hollow sucker rod 5 to dock the first connecting piece 7 and the second connecting piece 8. After the docking is completed, the built-in storage pressure gauge 9 is taken out using the wire rope 6, and the data is read on the ground. The entire operation process can be carried out without stopping the screw pump.

[0024] like Figure 5 As shown, the limiting device 10 is configured as a disc having a plurality of through holes, the disc being connected to the inner wall of the rotor 4, the through holes on the disc allowing liquid to pass through, the built-in storage pressure gauge 9 being located above the disc, and the built-in storage pressure gauge 9 being limited by the disc; in actual use, when the storage pressure gauge reaches above the disc, it will no longer move downward, and at this time the built-in storage pressure gauge 9 reaches a predetermined position.

[0025] It also includes a ground water-gas separation tank 13, one side of which is connected to a liquid reinjection pipe 14, which is communicated with the universal rotary joint 2, and the other side of the ground water-gas separation tank 13 is connected to an exhaust pipe 17, the top surface of the ground water-gas separation tank 13 is connected to a liquid inlet pipe 15 and an overflow pipe 16, the liquid inlet pipe 15 is communicated with the liquid outlet tee 12, and valves 19 and pressure gauges 20 are installed on the liquid reinjection pipe 14, the liquid inlet pipe 15 and the exhaust pipe 17, and the bottom surface of the ground water-gas separation tank 13 is connected to a sewage pipe 18, and a sewage valve 21 is installed on the sewage pipe 18. The sewage pipe 18 is provided to facilitate the discharge of impurities inside the ground water-gas separation tank 13.

[0026] like Figure 6As shown, the ground water-gas separation tank 13 includes a tank body 13-1, and a plurality of first liquid-passing partitions 13-2 and second liquid-passing partitions 13-3 are staggeredly connected inside the tank body 13-1. The top surface of the first liquid-passing partition 13-2 is flush with the top surface of the tank body 13-1, and a first liquid-passing channel is arranged below the first liquid-passing partition 13-2. The bottom surface of the second liquid-passing partition 13-3 is flush with the bottom surface of the tank body 13-1, and a second liquid-passing channel is arranged above the second liquid-passing partition 13-3. A third liquid-passing partition 13-4 is also connected to the inside of the tank body 13-1 near the left side wall, and the top of the third liquid-passing partition 13-4 Filter cotton 13-5 is installed in the interlayer; in this embodiment, liquid-passing baffles of different heights are installed inside the separation tank. The liquid extracted from the well is lifted to the position of the liquid outlet tee 12 through the oil pipe, and then enters the tank body 13-1 through the liquid inlet pipe 15, first passing through the first liquid-passing channel below the first liquid-passing baffle 13-2, and then passing through the second liquid-passing channel above the second liquid-passing baffle 13-3. The liquid flow direction is changed by the height displacement difference, and the liquid is filtered through the filter cotton 13-5 in the interlayer. At the same time, the liquid flows from low to high and then from high to low in an S-shaped state, relying on the gravity of the liquid to achieve gas-liquid separation.

[0027] The rotor 4 works, causing the underground water-gas mixture to enter the interior of the pump through the liquid inlet below the rotor 4. The rotation of the rotor 4 drives the water-gas mixture to rise, and finally the water-gas mixture enters the liquid outlet tee 12, and enters the surface water-gas separation tank 13 through the liquid inlet pipe 15. After treatment, the gas is discharged through the exhaust pipe 17, and the liquid remains in the surface water-gas separation tank 13. Finally, this part of the liquid can be injected into the hollow sucker rod 5 through the liquid reinjection pipe 14, and then enter the rotor 4, and finally enter the bottom of the rotor 4 to flush the liquid inlet end of the pump, dilute the coal powder at the liquid inlet and near-wellbore area, and at the same time, the formation fluid can be replenished.

[0028] In addition, chemicals can be added into the well through the hollow sucker rod 5 to achieve functions such as chemical scale inhibition.

[0029] The embodiments described above are only descriptions of the preferred methods of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the protection scope determined by the claims of the present invention.

Claims

1. A wireless downhole liquid level monitoring screw pump, comprising a pipe string (11), characterized in that: The tubular column (11) is provided with a stator (3) and a rotor (4) for use together, a hollow sucker rod (5) is provided on the upper part of the rotor (4), an oil pipe (22) is provided on the upper part of the stator (3), a liquid outlet tee (12) is provided on the top surface of the tubular column (11), a ground driving device (1) for driving the hollow sucker rod (5) is provided above the ground wellhead, a universal rotating joint (2) is provided on the top of the bare rod of the hollow sucker rod (5), the rotor (4) is configured as a hollow structure, a built-in storage pressure gauge (9) is provided in the rotor (4), a lifting assembly is provided above the built-in storage pressure gauge (9), and a limiting device (10) for limiting the position of a monitoring device is provided at the bottom of the rotor (4).

2. The wireless downhole liquid level monitoring screw pump according to claim 1 is characterized in that: The lifting assembly includes a second connecting member (8), which is arranged on the top of the built-in storage pressure gauge (9), and a first connecting member (7) for docking with the second connecting member (8) is arranged above the second connecting member (8), and a steel wire rope (6) is arranged above the first connecting member (7).

3. The wireless downhole liquid level monitoring screw pump according to claim 1 is characterized in that: It also comprises a ground water-gas separation tank (13), one side of which is provided with a liquid reinjection pipe (14), the liquid reinjection pipe (14) being in communication with the universal rotary joint (2), the other side of which is provided with an exhaust pipe (17), the top surface of which is provided with a liquid inlet pipe (15) and an overflow pipe (16), the liquid inlet pipe (15) being in communication with the liquid outlet tee (12), and the bottom surface of which is provided with a sewage discharge pipe (18).

4. The wireless downhole liquid level monitoring screw pump according to claim 3 is characterized in that: The liquid refill pipe (14), the liquid inlet pipe (15) and the exhaust pipe (17) are all installed with a valve (19) and a pressure gauge (20).

5. The wireless downhole liquid level monitoring screw pump according to claim 3 is characterized in that: A sewage valve (21) is installed on the sewage pipe (18).

6. The wireless downhole liquid level monitoring screw pump according to claim 3 is characterized in that: The ground water-gas separation tank (13) comprises a tank body (13-1), wherein a plurality of first liquid-passing baffles (13-2) and second liquid-passing baffles (13-3) are staggeredly connected inside the tank body (13-1), wherein the top surface of the first liquid-passing baffles (13-2) is flush with the top surface of the tank body (13-1), and a first liquid-passing channel is arranged below the first liquid-passing baffles (13-2), and the bottom surface of the second liquid-passing baffles (13-3) is flush with the bottom surface of the tank body (13-1), and a second liquid-passing channel is arranged above the second liquid-passing baffles (13-3), and a third liquid-passing baffle (13-4) is also connected to the inside of the tank body (13-1) near the left side wall, and a filter cotton (13-5) is installed in the top interlayer of the third liquid-passing baffles (13-4).

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