A process string for vibration plug removal and its operation method

Abstract

The present invention provides a process string for vibration plugging removal and its operation method, which includes a centralizing mechanism, a backwashing valve, a filtering short section, a power mechanism, a torque transmission mechanism, an amplitude generating mechanism, an impact mechanism, a rotary flushing mechanism and a flushing head. The centralizing mechanism, the backwashing valve, the filtering short section, the power mechanism, the torque transmission mechanism, the amplitude generating mechanism, the impact mechanism, the rotary flushing mechanism and the flushing head are connected end to end in sequence from top to bottom. The present invention can simultaneously achieve the dual functions of radial vibration plugging removal and hydraulic pulse plugging removal, not only can wash the deposited sand inside the screen pipe clean, but also can loosen the sand grains deposited on the outer surface of the screen pipe and the fine silt sand blocked in the screen network, improving the plugging removal efficiency of oil and gas wells.

Description

Technical Field

[0001] The present invention relates to the technical field of enhanced oil recovery, and more particularly to a process string for vibration plug removal and its operation method. Background Art

[0002] Most of the sand control wells in offshore oilfields adopt the simple sand control method with screens and the gravel packing sand control method with screens. In the later stage of oil and gas well development, formation particles, colloids, etc. near the wellbore of the reservoir migrate and accumulate towards the wellbore periphery, blocking the screen and causing a decrease in its permeability, a reduction in the amount of fluid flowing into the wellbore or no production, a decline in the oil well production, and ultimately resulting in production shutdown.

[0003] Currently, the methods for removing blockages in screens and formations mainly include physical plug removal methods and chemical plug removal methods. Among them, the physical plug removal methods mainly include hydraulic impact, ultrasonic plug removal, hydraulic oscillation plug removal, and electric pulse plug removal. Although the pollution is small, the plug removal effect is poor. The chemical plug removal method is mainly chemical acidification plug removal, but this method has a large investment, a complex process, and is prone to cause secondary pollution to the formation. Summary of the Invention

[0004] The present invention overcomes the deficiencies in the prior art. The existing physical plug removal methods have a poor plug removal effect. A process string for vibration plug removal and its operation method are provided. The present invention can simultaneously achieve the dual functions of radial vibration plug removal and hydraulic pulse plug removal. It can not only wash the deposited sand inside the screen clean, but also loosen the sand grain deposition on the outer surface of the screen and the fine silt blocked in the screen network distribution, improving the plug removal efficiency of oil and gas wells.

[0005] The object of the present invention is achieved by the following technical solutions.

[0006] A process string for vibration plug removal includes a centralizing mechanism, a backwash valve, a filtering short joint, a power mechanism, a torque transmission mechanism, an amplitude generating mechanism, an impact mechanism, a rotary flushing mechanism, and a flushing head. The centralizing mechanism, the backwash valve, the filtering short joint, the power mechanism, the torque transmission mechanism, the amplitude generating mechanism, the impact mechanism, the rotary flushing mechanism, and the flushing head are connected end to end in sequence from top to bottom;

[0007] The backwashing valve includes a backwashing sleeve, a piston sleeve, a spring and a limiting sleeve. The tail end of the centralizing mechanism is threadedly connected to the head end of the backwashing sleeve. A backwashing hole is formed in the lower side wall of the backwashing sleeve. An internal step is formed on the inner wall of the backwashing sleeve above the backwashing hole to limit the upward displacement of the piston sleeve. An upper limiting step and a lower limiting step are sequentially formed on the outer wall of the upper part of the piston sleeve from top to bottom. A circulation hole is formed in the lower side wall of the piston sleeve. The circulation hole is communicated with the backwashing hole to achieve the purpose of backwashing the well. The tail end of the piston sleeve is inserted into the head end of the limiting sleeve. A limiting sleeve step is formed on the outer wall of the middle part of the limiting sleeve. The spring is arranged between the piston sleeve and the limiting sleeve. The head end of the spring contacts the end face of the upper limiting step, and the tail end of the spring contacts the end face of the limiting sleeve step. The lower limiting step is used to limit the downward displacement of the piston sleeve. The tail end of the backwashing sleeve is threadedly connected to the head end of the filter nipple;

[0008] The amplitude generating mechanism includes an inner tube, an outer tube, an eccentric block and an eccentric sleeve. The inner tube is arranged inside the outer tube. The head end of the inner tube is threadedly connected to the tail end of the torque transmission mechanism. A through hole is formed in the outer wall of the upper part of the inner tube. An inner tube eccentric hole is formed in the inner cavity of the inner tube. The eccentric block is arranged in the middle of the outer wall of the inner tube. An inner tube step is formed on the outer wall of the tail end of the inner tube. The tail end of the outer tube is threadedly connected to the head end of the impact mechanism. The eccentric sleeve is arranged inside the head end of the impact mechanism, and the outer wall of the eccentric sleeve is threadedly connected to the inner wall of the impact mechanism. An eccentric sleeve inner hole is formed in the inner cavity of the eccentric sleeve. There is an eccentricity between the eccentric sleeve inner hole and the inner tube eccentric hole to achieve the purpose of periodically changing the effective flow area between the inner tube and the eccentric sleeve;

[0009] The rotary flushing mechanism includes a rotating tube, a bearing sleeve, a long key, a bearing, an outer connecting sleeve, a locking sleeve and a lower connecting sleeve. A radial reduced diameter step is formed on the outer wall of the head end of the rotating tube. The bearing and the bearing sleeve are sequentially arranged from bottom to top at the radial reduced diameter step. The outer connecting sleeve is sleeved outside the rotating tube. The head end of the outer connecting sleeve is threadedly connected to the tail end of the impact mechanism. The inner wall of the head end of the outer connecting sleeve and the bearing sleeve are key-connected by a long key to prevent the bearing sleeve from rotating. The tail end of the outer connecting sleeve is threadedly connected to the head end of the lower connecting sleeve. The tail end of the lower connecting sleeve is threadedly connected to the head end of the flushing head.

[0010] Filter sheets are uniformly arranged inside the filter nipple. Through holes are uniformly formed in the filter sheets to filter impurities in the high-pressure liquid flow.

[0011] The power mechanism includes a screw rotor and a stator. The screw rotor can partially convert the pressure energy of the high-pressure liquid flow into kinetic energy, so that the high-pressure liquid flow generates a rotational motion inside the stator.

[0012] The torque transmission mechanism includes an upper sub, a connecting rod and a lower sub. A spherical hinge connection structure is adopted between the connecting rod and the upper sub and the lower sub to achieve the purpose of transmitting torque when there is a radial deviation.

[0013] The eccentric block is installed on the thick side of the inner wall of the inner pipe. A notch penetrating the inner wall of the inner pipe is provided on the end face of the tail end of the inner pipe in the radial direction of the inner pipe.

[0014] An axial through hole is formed in the inner cavity of the impact mechanism, and a spiral flow guiding groove is formed on the outer wall of the impact mechanism.

[0015] An operation method of a work string for vibration plug removal is carried out according to the following steps:

[0016] Step 1, vibration plug removal process:

[0017] A high-pressure liquid flow is pumped into the work string through a ground pressurizing device. The high-pressure liquid flow enters the internal channel of the centralizing mechanism and flows through the inside of the backwashing valve. Since the internal channel of the piston sleeve becomes smaller, the piston sleeve moves to the right under the action of hydraulic pressure. The circulation hole on the piston sleeve moves into the limit sleeve, so that the circulation hole and the backwashing hole cannot communicate. The high-pressure liquid flow can only flow into the filter nipple through the inside of the piston sleeve, and then flow into the power mechanism. The power mechanism can convert part of the pressure energy of the high-pressure liquid flow into kinetic energy, so that the torque transmission mechanism and the amplitude generating mechanism connected to the tail end of the power mechanism rotate together. An eccentric block is provided in the amplitude generating mechanism, and radial vibration is generated while rotating. The impact mechanism is connected to the tail end of the amplitude generating mechanism. The impact mechanism vibrates radially and impacts the inner walls of the casing and the screen pipe. The high-pressure liquid flow passing through the power mechanism flows through the external space of the torque transmission mechanism, and then enters the eccentric hole of the inner pipe through the through hole on the inner wall of the inner pipe of the amplitude generating mechanism. Subsequently, after flowing through the inner hole of the eccentric sleeve - the impact mechanism - the rotating pipe - the washing head, after the high-pressure liquid flow flows through the washing head, part of it is ejected along the axial channel. Under the action of the ejection reaction force, the rotating pipe and the washing head rotate. The impact mechanism vibrates radially and impacts the inner walls of the casing and the screen pipe, thereby loosening the deposited sand flowing out from the formation outside the screen pipe and accumulating on the surface of the screen pipe and the fine silt blocking the screen pipe mesh holes. The washing head produces a rotating washing effect, thereby washing the deposited sand inside the screen pipe clean;

[0018] Step 2, well backwashing process:

[0019] During the above-mentioned vibration deblocking operation process, a large amount of sedimentary sand and other impurities flow into the annulus between the casing and the vibration deblocking process string and the screen pipe and the vibration deblocking process string. Due to the small displacement during the operation, the sedimentary sand and other impurities cannot be flushed to the ground. It is necessary to inject high-speed well washing fluid into the annulus between the casing and the vibration deblocking process string and the screen pipe and the vibration deblocking process string. The piston sleeve of the backwash valve contacts the internal step of the backwash sleeve under the thrust of the spring, and the backwash hole and the circulation hole are connected. The high-speed well washing fluid flushes the annulus between the casing and the vibration deblocking process string and the screen pipe and the vibration deblocking process string. The sedimentary sand and other impurities therein flow into the backwash valve through the backwash hole and the circulation hole, and are then circulated to the ground.

[0020] The beneficial effects of the present invention are as follows: the high-pressure fluid pumped into the ground enters the process string for vibration unblocking, and then the pressure energy is partially converted into kinetic energy through the power mechanism, and the kinetic energy is transmitted to the amplitude generating mechanism through the torque transmission mechanism. Since the amplitude generating mechanism has an eccentric structural design, radial vibration can be generated, and the vibration is transmitted to the impact mechanism, that is, the impact mechanism and the inner wall of the casing or screen tube produce impact vibration, loosening the sand deposited on the outer surface of the screen tube and the fine silt blocked in the screen tube mesh, and a rotating flushing effect is generated through the flushing head to clean the deposited sand inside the screen tube. The process string for vibration unblocking simultaneously realizes the dual effects of radial vibration unblocking and hydraulic pulse unblocking, thereby improving the unblocking efficiency of oil and gas wells, and solves the problem that the existing physical unblocking method has less pollution but its unblocking effect is poor, and the chemical unblocking method has a large investment, a complex process, and is prone to secondary pollution to the formation. The present invention has the characteristics of simple structure, strong reliability and good applicability, and has positive promotion significance for unblocking screen tube blockage. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the present invention;

[0022] Figure 2 It is a structural schematic diagram of the backwash valve in the present invention;

[0023] Figure 3 It is a structural schematic diagram of the amplitude generating mechanism of the present invention;

[0024] Figure 4 This is a schematic diagram of the position change of the eccentric block in the present invention;

[0025] Figure 5 It is a structural schematic diagram of the impact mechanism of the present invention;

[0026] Figure 6 It is a structural schematic diagram of the rotary flushing mechanism of the present invention;

[0027] In the figure: 1 is a straightening mechanism, 2 is a backwashing valve, 3 is a filtering nipple, 4 is a power mechanism, 5 is a torque transmission mechanism, 6 is an amplitude generating mechanism, 8 is an impact mechanism, 9 is a rotary flushing mechanism, 10 is a flushing head, 11 is a formation (casing), 12 is a screen pipe, 13 is a backwashing sleeve, 14 is a piston sleeve, 15 is a spring, 16 is a limit sleeve, 17 is an inner pipe, 18 is an outer pipe, 19 is an eccentric block, 20 is an eccentric sleeve, 22 is a spiral flow guide groove, 23 is a rotating pipe, 24 is a bearing sleeve, 25 is a long key, 26 is a bearing, 27 is an outer connecting sleeve, 28 is a locking sleeve, 29 is a lower connecting sleeve, 101 is a backwashing hole, 102 is a circulation hole, 103 is an eccentric hole of the inner pipe, 104 is an inner hole of the eccentric sleeve.

[0028] For those of ordinary skill in the art, without creative efforts, other relevant drawings can be obtained based on the above drawings. Specific embodiments

[0029] The technical solution of the present invention will be further described below through specific embodiments.

[0030] Embodiment 1

[0031] A process string for vibration plug removal includes a straightening mechanism 1, a backwashing valve 2, a filtering nipple 3, a power mechanism 4, a torque transmission mechanism 5, an amplitude generating mechanism 6, an impact mechanism 8, a rotary flushing mechanism 9 and a flushing head 10. The straightening mechanism 1, the backwashing valve 2, the filtering nipple 3, the power mechanism 4, the torque transmission mechanism 5, the amplitude generating mechanism 6, the impact mechanism 8, the rotary flushing mechanism 9 and the flushing head 10 are connected end to end in sequence from top to bottom;

[0032] The backwashing valve 2 includes a backwashing sleeve 13, a piston sleeve 14, a spring 15 and a limit sleeve 16. The tail end of the straightening mechanism 1 is threadedly connected to the head end of the backwashing sleeve 13. A backwashing hole 101 is formed on the lower side wall of the backwashing sleeve 13. An internal step is formed on the inner wall of the backwashing sleeve 13 above the backwashing hole 101 to limit the upward displacement of the piston sleeve 14. An upper limit step and a lower limit step are sequentially formed on the upper outer wall of the piston sleeve 14 from top to bottom. A circulation hole 102 is formed on the lower side wall of the piston sleeve 14. The circulation hole 102 is connected to the backwashing hole 101 to achieve the purpose of backwashing the well. The tail end of the piston sleeve 14 is inserted into the head end of the limit sleeve 16. A limit sleeve step is formed on the middle outer wall of the limit sleeve 16. A spring 15 is arranged between the piston sleeve 14 and the limit sleeve 16. The head end of the spring 15 is in contact with the end face of the upper limit step, and the tail end of the spring 15 is in contact with the end face of the limit sleeve step. The lower limit step is used to limit the downward displacement of the piston sleeve 14. The tail end of the backwashing sleeve 13 is threadedly connected to the head end of the filtering nipple 3;

[0033] The amplitude generating mechanism 6 includes an inner tube 17, an outer tube 18, an eccentric block 19 and an eccentric sleeve 20. The inner tube 17 is arranged inside the outer tube 18. The head end of the inner tube 17 is threadedly connected to the tail end of the torque transmission mechanism 5. A through hole is provided on the outer wall of the upper part of the inner tube 17. The inner cavity of the inner tube 17 forms an inner tube eccentric hole 103. The eccentric block 19 is arranged in the middle of the outer wall of the inner tube 17. An inner tube step is formed on the outer wall of the tail end of the inner tube 17. The tail end of the outer tube 18 is threadedly connected to the head end of the impact mechanism 8. The eccentric sleeve 20 is arranged inside the head end of the impact mechanism 7, and the outer wall of the eccentric sleeve 20 is threadedly connected to the inner wall of the impact mechanism 7. The inner cavity of the eccentric sleeve 20 forms an eccentric sleeve inner hole 104. There is an eccentricity between the eccentric sleeve inner hole 104 and the inner tube eccentric hole 103 to achieve the purpose of periodically changing the effective flow area between the inner tube 17 and the eccentric sleeve 20.

[0034] The rotary flushing mechanism 9 includes a rotating tube 23, a bearing sleeve 24, a long key 25, a bearing 26, an outer connecting sleeve 27, a locking sleeve 28 and a lower connecting sleeve 29. A radial reduced diameter step is formed on the outer wall of the head end of the rotating tube 23. The bearing 26 and the bearing sleeve 24 are sequentially arranged from bottom to top at the radial reduced diameter step. The outer connecting sleeve 27 is sleeved outside the rotating tube 23. The head end of the outer connecting sleeve 27 is threadedly connected to the tail end of the impact mechanism 8. The inner wall of the head end of the outer connecting sleeve 27 and the bearing sleeve 24 are key-connected by the long key 25 to prevent the bearing sleeve 24 from rotating. The tail end of the outer connecting sleeve 27 is threadedly connected to the head end of the lower connecting sleeve 29. The tail end of the lower connecting sleeve 29 is threadedly connected to the head end of the flushing head 10.

[0035] Embodiment Two

[0036] On the basis of Embodiment One, filter sheets are uniformly arranged inside the filter nipple 3, and through holes are uniformly provided on the filter sheets for filtering impurities in the high-pressure liquid flow.

[0037] The power mechanism 4 includes a screw rotor and a stator. The screw rotor can partially convert the pressure energy of the high-pressure liquid flow into kinetic energy, so that the high-pressure liquid flow generates a rotational motion inside the stator.

[0038] The torque transmission mechanism 5 includes an upper joint, a connecting rod and a lower joint. A spherical hinge connection structure is adopted between the connecting rod and the upper joint and the lower joint to achieve the purpose of transmitting torque when there is a radial deviation.

[0039] Embodiment Three

[0040] On the basis of Embodiment Two, the eccentric block 19 is installed on the thick side of the tube wall of the inner tube 17, and a notch penetrating the tube wall of the inner tube 17 is provided on the end face of the tail end of the inner tube 17 along the radial direction of the inner tube 17.

[0041] An axial through hole is formed in the inner cavity of the impact mechanism 8, and a spiral flow guiding groove 22 is formed on the outer wall of the impact mechanism 7.

[0042] Example 4

[0043] An operation method for a process string for vibration plug removal is carried out according to the following steps:

[0044] Step 1, vibration plug removal process:

[0045] A high-pressure liquid flow is pumped into the process string through a ground pressurizing device. The high-pressure liquid flow enters the internal channel of the centralizer 1 and flows through the inside of the backwashing valve 2. Since the internal channel of the piston sleeve 14 becomes smaller, the piston sleeve 14 moves to the right under the action of hydraulic pressure. The circulation hole on the piston sleeve 14 moves into the limit sleeve 16, making the circulation hole 102 unable to communicate with the backwashing hole 101. The high-pressure liquid flow can only flow into the filter nipple 3 through the inside of the piston sleeve 14 and then into the power mechanism 4. The power mechanism 4 can convert part of the pressure energy of the high-pressure liquid flow into kinetic energy, so that the torque transmission mechanism 5 and the amplitude generating mechanism 6 connected to the tail end of the power mechanism 4 rotate together. An eccentric block 20 is provided in the amplitude generating mechanism 6, and radial vibration is also generated while rotating. The impact mechanism 8 is connected to the tail end of the amplitude generating mechanism 6. The impact mechanism 8 vibrates radially and impacts the inner walls of the casing 11 and the screen pipe 12. The high-pressure liquid flow passing through the power mechanism 4 flows through the outer space of the torque transmission mechanism 5 and then enters the inner pipe eccentric hole 103 through the through hole on the inner pipe wall of the amplitude generating mechanism 6. Subsequently, after flowing through the eccentric sleeve inner hole 104 - the impact mechanism 8 - the rotating pipe 23 - the washing head 10, after the high-pressure liquid flow passes through the washing head 10, part of it is ejected along the axial channel. Under the action of the ejection reaction force, the rotating pipe 23 and the washing head 10 rotate. The impact mechanism 8 vibrates radially and impacts the inner walls of the casing 11 and the screen pipe 1, thus loosening the sediment sand flowing out from the formation and accumulating on the surface of the screen pipe 12 and the fine silt blocking the mesh holes of the screen pipe 12. The washing head 10 produces a rotating washing effect, thus washing the sediment sand inside the screen pipe 12 clean;

[0046] Step 2, backwashing well process:

[0047] During the operation of the above-mentioned vibration plug removal, a large amount of deposited sand and other impurities flow into the annulus between the casing 11 and the vibration plug removal string, and between the screen pipe 12 and the vibration plug removal string. Since the displacement is small during the operation and the deposited sand and other impurities cannot be flushed to the ground, it is necessary to inject high-speed well-washing fluid into the annulus between the casing 11 and the vibration plug removal string, and between the screen pipe 12 and the vibration plug removal string. The piston sleeve 14 of the backwashing valve 2 contacts the inner step of the backwashing sleeve 13 under the thrust of the spring, and the backwashing hole 101 communicates with the circulation hole 102. The high-speed well-washing fluid flushes the annulus between the casing 11 and the vibration plug removal string, and between the screen pipe 12 and the vibration plug removal string. The deposited sand and other impurities therein flow into the backwashing valve 2 through the backwashing hole 101 and the circulation hole 102, and are then circulated to the ground.

[0048] For ease of explanation, spatial relative terms such as "upper", "lower", "left", "right", etc. are used in the embodiments to describe the relationship of one element or feature shown in the figure relative to another element or feature. It should be understood that, in addition to the orientation shown in the figure, the spatial terms are intended to include different orientations during the use or operation of the device. For example, if the device in the figure is inverted, the element described as being "below" other elements or features will be positioned "above" the other elements or features. Therefore, the exemplary term "lower" can include both upper and lower orientations. The device can be positioned in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein can be interpreted accordingly.

[0049] Moreover, relative relationship terms such as "first" and "second" are only used to distinguish one component with the same name from another, and do not necessarily require or imply any such actual relationship or order between these components.

[0050] The above has described the present invention in detail, but the content described is only the preferred embodiment of the present invention and cannot be considered as used to limit the scope of implementation of the present invention. All equal changes and improvements made according to the scope of the application of the present invention should still fall within the scope covered by the patent of the present invention.

Claims

1. A process string for vibration plug removal, characterized in that: It includes a straightening mechanism, a backwashing valve, a filtering short section, a power mechanism, a torque transmission mechanism, an amplitude generating mechanism, an impact mechanism, a rotary flushing mechanism and a flushing head. The straightening mechanism, the backwashing valve, the filtering short section, the power mechanism, the torque transmission mechanism, the amplitude generating mechanism, the impact mechanism, the rotary flushing mechanism and the flushing head are connected end to end in sequence from top to bottom; The backwashing valve includes a backwashing sleeve, a piston sleeve, a spring and a limiting sleeve. The tail end of the straightening mechanism is threadedly connected to the head end of the backwashing sleeve. A backwashing hole is provided on the lower side wall of the backwashing sleeve. An internal step is formed on the inner wall of the backwashing sleeve above the backwashing hole to limit the upward displacement of the piston sleeve. An upper limiting step and a lower limiting step are sequentially formed on the outer wall of the upper part of the piston sleeve. A circulation hole is provided on the lower side wall of the piston sleeve, and the circulation hole is communicated with the backwashing hole to achieve the purpose of backwashing the well. The tail end of the piston sleeve is inserted into the head end of the limiting sleeve. A limiting sleeve step is formed on the outer wall of the middle part of the limiting sleeve. The spring is arranged between the piston sleeve and the limiting sleeve. The head end of the spring is in contact with the end face of the upper limiting step, and the tail end of the spring is in contact with the end face of the limiting sleeve step. The lower limiting step is used to limit the downward displacement of the piston sleeve. The tail end of the backwashing sleeve is threadedly connected to the head end of the filtering short section; The amplitude generating mechanism includes an inner tube, an outer tube, an eccentric block and an eccentric sleeve. The inner tube is arranged inside the outer tube. The head end of the inner tube is threadedly connected to the tail end of the torque transmission mechanism. A through hole is provided on the outer wall of the upper part of the inner tube. An inner tube eccentric hole is formed in the inner cavity of the inner tube. The eccentric block is arranged in the middle of the outer wall of the inner tube. An inner tube step is formed on the outer wall of the tail end of the inner tube. The tail end of the outer tube is threadedly connected to the head end of the impact mechanism. The eccentric sleeve is arranged inside the head end of the impact mechanism, and the outer wall of the eccentric sleeve is threadedly connected to the inner wall of the impact mechanism. An eccentric sleeve inner hole is formed in the inner cavity of the eccentric sleeve. There is an eccentricity between the eccentric sleeve inner hole and the inner tube eccentric hole to achieve the purpose of periodically changing the effective flow area between the inner tube and the eccentric sleeve; The rotary flushing mechanism includes a rotating tube, a bearing sleeve, a long key, a bearing, an outer connecting sleeve, a locking sleeve and a lower connecting sleeve. A radial reduced diameter step is formed on the outer wall of the head end of the rotating tube. The bearing and the bearing sleeve are sequentially arranged from bottom to top at the radial reduced diameter step. The outer connecting sleeve is sleeved outside the rotating tube. The head end of the outer connecting sleeve is threadedly connected to the tail end of the impact mechanism. The inner wall of the head end of the outer connecting sleeve and the bearing sleeve are key-connected by a long key to prevent the bearing sleeve from rotating. The tail end of the outer connecting sleeve is threadedly connected to the head end of the lower connecting sleeve. The tail end of the lower connecting sleeve is threadedly connected to the head end of the flushing head.

2. The process string for vibration plug removal according to claim 1, wherein: Filtering sheets are evenly arranged inside the filtering short section, and through holes are evenly formed in the filtering sheets for filtering impurities in the high-pressure liquid flow.

3. The process string for vibration plug removal according to claim 1, characterized in that: The power mechanism includes a screw rotor and a stator. The screw rotor can convert part of the pressure energy of the high-pressure liquid flow into kinetic energy, causing the high-pressure liquid flow to generate a rotational motion inside the stator.

4. A process string for vibration plug removal according to claim 1, characterized in that: The torque transmission mechanism includes an upper joint, a connecting rod, and a lower joint. A spherical hinge connection structure is adopted between the connecting rod and the upper joint and the lower joint to achieve the purpose of transmitting torque when there is a radial deviation.

5. A process string for vibration plug removal according to claim 1, characterized in that: The eccentric block is installed on the thick side of the inner wall of the inner tube. A notch penetrating the inner wall of the inner tube is formed on the end face of the tail end of the inner tube in the radial direction of the inner tube.

6. The process string for vibration plug removal according to claim 1, wherein: An axial through-hole is formed in the inner cavity of the impact mechanism, and a spiral flow guiding groove is formed on the outer wall of the impact mechanism.

7. The operation method of a process string for vibration plug removal as described in any one of claims 1-6, characterized in that: It is carried out according to the following steps: Step 1, vibration plug removal process: Pump high-pressure liquid flow into the process pipe string through a ground pressurizing device. The high-pressure liquid flow enters the internal channel of the centralizing mechanism and flows through the inside of the backwashing valve. Since the internal channel of the piston sleeve becomes smaller, the piston sleeve moves to the right under the action of hydraulic pressure. The circulation hole on the piston sleeve moves into the limit sleeve, making the circulation hole and the backwashing hole unable to communicate. The high-pressure liquid flow can only flow into the filter nipple through the inside of the piston sleeve and then into the power mechanism. The power mechanism can convert part of the pressure energy of the high-pressure liquid flow into kinetic energy, causing the torque transmission mechanism and the amplitude generating mechanism connected to the tail end of the power mechanism to rotate together. An eccentric block is provided in the amplitude generating mechanism, and radial vibration is also generated during the rotational motion. The impact mechanism is connected to the tail end of the amplitude generating mechanism. The impact mechanism vibrates radially and impacts the inner walls of the casing and the screen pipe. The high-pressure liquid flow passing through the power mechanism flows through the external space of the torque transmission mechanism, then enters the eccentric hole of the inner tube through the through-hole on the inner wall of the inner tube of the amplitude generating mechanism, and then flows through the inner hole of the eccentric sleeve - the impact mechanism - the rotating pipe - the washing head. After the high-pressure liquid flow passes through the washing head, part of it is ejected along the axial channel. Under the action of the ejection reaction force, the rotating pipe and the washing head rotate. The impact mechanism vibrates radially and impacts the inner walls of the casing and the screen pipe, further loosening the sediment sand flowing out from the formation and accumulating on the surface of the screen pipe and the fine silt blocking the screen pipe mesh holes. The washing head produces a rotating flushing effect, thereby flushing the sediment sand inside the screen pipe clean. Step 2, backwashing well process: During the operation of the above-mentioned vibration plug removal process, a large amount of sediment sand and other impurities flow into the annulus between the casing and the vibration plug removal process pipe string and between the screen pipe and the vibration plug removal process pipe string. Since the displacement is small during the operation process and the sediment sand and other impurities cannot be flushed to the ground, it is necessary to inject high-speed well washing fluid into the annulus between the casing and the vibration plug removal process pipe string and between the screen pipe and the vibration plug removal process pipe string. The piston sleeve of the backwashing valve contacts the inner step of the backwashing sleeve under the thrust of the spring, and the backwashing hole and the circulation hole are connected. The high-speed well washing fluid flushes the annulus between the casing and the vibration plug removal process pipe string and between the screen pipe and the vibration plug removal process pipe string. The sediment sand and other impurities therein flow into the backwashing valve through the backwashing hole and the circulation hole and are then circulated to the ground.

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