Sand blocking prevention oil extraction pipe column

Abstract

The utility model belongs to the field of equipment for extracting oil from a well, and particularly relates to a sand blocking prevention oil extraction pipe column. In order to solve the technical problems that in the prior art, when stratum sand production is serious, the sand blocking phenomenon occurs, and workers have to overhaul an oil well, the sand blocking prevention oil extraction pipe column comprises an oil-submerged pump and a driving motor, and the side, away from the oil-submerged pump, of the driving motor is connected with an overflowing structure; the overflowing structure comprises a packer, an overflowing runner, a liquid inlet and a liquid outlet, wherein the packer is located on one side of all the casing holes and divides the oil sleeve annulus into a liquid outlet annulus and a liquid inlet annulus in the using process, the liquid inlet is used for communicating the overflowing runner with the liquid inlet annulus, and the liquid outlet is used for communicating the overflowing runner with the liquid outlet annulus. When the liquid inlet of the uniflow structure is buried by sand, formation liquid cannot enter the liquid outlet annulus, so that the formation liquid conveyed to the well mouth by the oil-submerged pump is reduced, a worker is reminded of overhauling, at the moment, the length of the driving motor, the oil-submerged pump and the pipe column which are buried by sand is short, and an oil well does not need to be overhauled.

Description

Technical Field

[0001] The utility model belongs to the field of equipment for oil extraction from wells, and particularly relates to a sand prevention and sticking oil production tubing string. Background Technique

[0002] For directional wells and horizontal wells with complex wellbore trajectories and large dogleg degrees, if the rod pumping technology is adopted, the rod and tubing will be eccentrically worn. When the rod and tubing are worn to a certain extent, the rod and tubing will break. Therefore, for directional wells and horizontal wells with complex wellbore trajectories and large dogleg degrees, the rodless pumping technology can be adopted.

[0003] In the rodless pumping technology, a submersible pump and a supporting drive motor are used. The submersible pump is generally a submersible screw pump, a submersible piston pump or a submersible centrifugal pump driven by a drive motor. Workers can adjust the working parameters of the drive motor and detect the working state of the drive motor through control devices such as a control cabinet or a control computer located outside the well to control the working parameters of the submersible pump and monitor the working state of the submersible pump.

[0004] For example, the Chinese utility model patent with the authorization announcement number of CN200943573Y and the authorization announcement date of September 5, 2007 discloses a reciprocating submersible electric pump oil production device. The oil production device includes a tubing and a cable. The lower end of the tubing is connected with a submersible piston pump (i.e., a submersible pump), and the lower end of the submersible piston pump is connected with a linear motor (equivalent to a drive motor for driving the submersible pump is connected to one end of the submersible pump). The cable is electrically connected to the linear motor to supply power to the linear motor. The submersible piston pump and the linear motor are both located in the casing, and the linear motor is located at the oil layer and is always immersed in the formation fluid, so as to use the formation fluid to cool the linear motor and avoid overheating of the linear motor. The above oil production device is applicable to the situation of a single oil layer (single oil layer oil production) or a situation where the pressure difference between two or more oil layers is not large (layered combined production).

[0005] In the case where the pressure difference between two oil layers is large, if the above-mentioned technology of single submersible piston pump oil production is adopted, the pressure of the liquid entering the annulus between the tubing and the casing in the oil layer with a larger pressure is large, and the pressure of the oil layer with a smaller pressure cannot be much greater than the pressure in the annulus between the tubing and the casing, resulting in the liquid in the oil layer with a larger pressure not flowing into the annulus between the tubing and the casing. In order to avoid the above situation, the technical solution of arranging submersible pumps on both the upper and lower sides of the linear motor is also disclosed in the above-mentioned utility model patent. A packer is set to separate the upper oil layer and the lower oil layer. The lower submersible pump pumps the oil fluid of the lower oil layer to the upper oil layer, and the upper submersible pump pumps the oil fluid of the upper oil layer and the oil fluid of the lower oil layer pumped to the upper oil layer to the wellhead. At this time, the two oil layers are separately produced by using two submersible pumps. In all technical solutions, the linear motor is located at the oil production layer to cool the linear motor with the formation fluid.

[0006] When using the oil production device in the above-mentioned utility model to produce oil from a single oil layer or to conduct combined production of two or more oil layers in a layered manner, sand in the oil production layer will enter the casing together with the formation fluid through the casing holes on the casing. When the sand production in the oil production layer is severe, a large amount of sand in the oil production layer will enter the casing and bury the formation fluid inlets of the linear motor and the submersible plunger pump, resulting in the inability of the submersible plunger pump to work, thereby causing a decrease in the liquid production of the oil well or no liquid production. After the staff discovers the abnormal liquid production of the oil well, they need to lift out the tubing string for maintenance. At this time, since the linear motor and the submersible plunger pump are more than ten meters long, and the formation fluid inlets of the linear motor and the submersible plunger pump have been buried by sand, the tubing string has been buried by sand for a long length and a sand sticking phenomenon has occurred (the sand sticking phenomenon refers to the phenomenon that during the oil production process, due to the formation sand burying a long length of the tubing string and the large friction between the tubing string and the formation sand, the tubing string cannot be lifted out of the wellhead). The staff cannot lift the downhole tubing string out of the wellhead, nor can they take out the submersible plunger pump from the well for maintenance. Therefore, the staff must carry out major repair operations on the oil well. Summary of the Utility Model

[0007] The purpose of the present utility model is to provide an anti-sand sticking oil production tubing string to solve the technical problem that when the existing oil production device produces oil from a single oil layer or conducts combined production of two or more oil layers in a layered manner, after the staff discovers the abnormal liquid production of the oil well, the sand in the formation has buried the formation fluid inlets of the linear motor and the submersible plunger pump, resulting in the tubing string being buried by sand for a long length, and the staff cannot lift the downhole tubing string out of the wellhead and must carry out major repair operations on the oil well.

[0008] To achieve the above purpose, the technical solution of the anti-sand sticking oil production tubing string provided by the present utility model is as follows:

[0009] An anti-sand sticking oil production tubing string includes a submersible oil pump and a driving motor for driving the submersible oil pump. An over-current structure is connected to the side of the driving motor away from the submersible oil pump. The over-current structure includes a packer that is located on one side of all the casing holes during use and divides the oil-casing annulus into a liquid outlet annulus and an inlet annulus directly communicating with the casing holes. The over-current structure further includes an over-current flow channel, an inlet for connecting the over-current flow channel with the inlet annulus, and an outlet for connecting the over-current flow channel with the liquid outlet annulus. The submersible oil pump, the driving motor, and the outlet are located on one side of the packer, and the inlet is located on the other side of the packer.

[0010] Furthermore, the over-current structure further includes a safety joint.

[0011] Furthermore, the safety joint is located between the packer and the driving motor.

[0012] Furthermore, an inlet screen pipe is connected to the side of the packer away from the driving motor, and the screen holes of the inlet screen pipe form the above-mentioned inlet.

[0013] Furthermore, a liquid outlet screen pipe is connected to the side of the packer away from the liquid inlet screen pipe, and the screen holes of the liquid outlet screen pipe form the described liquid outlet.

[0014] Furthermore, the flow-through structure further includes a check valve, and the flow channels in the liquid inlet screen pipe, the packer, the check valve, and the liquid outlet screen pipe together form the described flow-through channel.

[0015] Furthermore, a plug is connected to the end of the liquid inlet screen pipe away from the packer.

[0016] Furthermore, the sand control and anti-sticking oil production pipe string further includes a cable electrically connected to the driving motor and used to control the driving motor.

[0017] Furthermore, a submersible oil pump is connected to the end of the driving motor away from the flow-through structure, a tubing is connected to the end of the submersible oil pump away from the driving motor, and the cable is provided with a clip for clamping the cable to the outer wall of the tubing.

[0018] Furthermore, a submersible plunger pump is connected to the end of the driving motor away from the flow-through structure, and the driving motor is a linear motor.

[0019] The beneficial effects of the sand control and anti-sticking oil production pipe string of the present utility model are as follows: The present utility model is an improved invention. When oil production is carried out on a single oil layer or commingled production of two or more oil layers is carried out, the driving motor can drive the submersible oil pump to move for oil production; the packer can separate the oil-casing annulus into a liquid outlet annulus and a liquid inlet annulus. Among them, the liquid inlet annulus corresponds to the oil production layer and is communicated with the casing hole, so that the formation fluid in the formation can directly enter the liquid inlet annulus, and the liquid outlet annulus does not correspond to the casing hole, and the formation fluid cannot enter the liquid outlet annulus through the casing hole; the liquid inlet annulus and the liquid outlet annulus are communicated through the liquid inlet, the flow-through channel and the liquid outlet, so that the formation fluid in the liquid inlet annulus can flow into the liquid outlet annulus and cool the driving motor. At the same time, the submersible oil pump can transport the formation fluid in the liquid outlet annulus to the wellhead. After the formation sand enters the liquid inlet annulus along with the formation fluid, the formation sand will bury the liquid inlet, resulting in no formation fluid flowing out of the liquid outlet. At the same time, since the submersible oil pump is still continuously transporting the existing formation fluid in the liquid outlet annulus to the wellhead, the formation fluid in the liquid outlet annulus is continuously reduced, and then the speed of the formation fluid being transported by the submersible oil pump is continuously slowed down, resulting in abnormal wellhead liquid production, so that the staff can know that the sand control and anti-sticking oil production pipe string has an abnormality and needs to be repaired. At this time, the formation sand only buries the liquid inlet of the flow-through channel and does not bury the formation fluid inlets of the driving motor and the submersible oil pump. The length of the sand control and anti-sticking oil production pipe string buried by sand is only more than one meter or several meters, and there will be no sand sticking phenomenon. The staff can easily lift out the sand control and anti-sticking oil production pipe string, thus avoiding major repair operations on the oil well. Description of the Drawings

[0020] Figure 1This is a schematic structural diagram of a specific embodiment of the sand control and anti - sticking production tubing string of the present utility model.

[0021] Explanation of reference numerals in the drawings:

[0022] 1. Cable; 2. Tubing; 3. Submersible plunger pump; 4. Linear motor; 5. Safety joint; 6. Liquid outlet screen pipe; 61. Liquid outlet; 7. Check valve; 8. Packer; 9. Liquid inlet screen pipe; 91. Liquid inlet; 10. Plug; 11. Casing; 12. Oil production layer; 13. Liquid inlet annulus; 14. Liquid outlet annulus; 15. Casing hole. Specific embodiments

[0023] To solve the problems in the background art, the core inventive concept of the present utility model is as follows: The packer is used to divide the oil - casing annulus into a liquid inlet annulus and a liquid outlet annulus. Among them, the liquid inlet annulus corresponds to the oil production layer and is directly connected to the casing hole so that formation fluid can directly enter the liquid inlet annulus. The liquid outlet annulus does not correspond to the oil production layer to prevent formation fluid from directly entering the liquid outlet annulus through the casing hole. The liquid inlet annulus and the liquid outlet annulus are connected through a flow - through channel to transport the formation fluid in the liquid inlet annulus to the liquid outlet annulus, and a submersible oil pump is used to transport the formation fluid in the liquid outlet annulus to the wellhead. When sand in the oil production layer enters the liquid inlet annulus and buries the liquid inlet of the flow - through channel, the formation fluid can no longer flow from the liquid inlet annulus into the liquid outlet annulus. At the same time, since the submersible oil pump is still continuously transporting the existing formation fluid in the liquid outlet annulus to the wellhead, the formation fluid in the liquid outlet annulus is continuously reduced. As a result, the speed at which the formation fluid is transported by the submersible oil pump is continuously slowed down, leading to abnormal wellhead liquid production. Thus, it can enable the staff to know that the sand control and anti - sticking production tubing string has an abnormality and needs maintenance. At this time, the formation sand only buries the liquid inlet of the flow - through channel and does not bury the liquid inlets of the drive motor and the submersible oil pump. The length of the sand - buried part of the sand control and anti - sticking production tubing string is only more than one meter or several meters, and there will be no sand - sticking phenomenon. The staff can easily lift out the sand control and anti - sticking production tubing string, thus avoiding major repair operations on the oil well.

[0024] The following further describes the present utility model in detail with reference to embodiments.

[0025] Specific embodiments of the sand control and anti - sticking production tubing string provided by the present utility model:

[0026] As Figure 1As shown, as a specific embodiment, the sand control and sticking prevention production tubing string includes a submersible pump and a drive motor for driving the submersible pump. One end of the submersible pump away from the drive motor is connected to a tubing 2 for delivering the oil fluid to the wellhead. One side of the drive motor away from the submersible pump is connected to a current passing structure. The current passing structure includes a packer 8 which is located on one side of all the casing holes 15 during use and divides the oil-casing annulus into a liquid outlet annulus 14 and an inlet liquid annulus 13 directly communicating with the casing holes 15. The current passing structure further includes a current passing flow channel, an inlet liquid port 91 for connecting the current passing flow channel with the inlet liquid annulus, and an outlet liquid port 61 for connecting the current passing flow channel with the liquid outlet annulus. The drive motor and the outlet liquid port 61 are located on one side of the packer 8, and the inlet liquid port 91 is located on the other side of the packer 8.

[0027] Specifically, in order to simplify the structure, as Figure 1 shown, one end of the drive motor away from the current passing structure is connected to a submersible plunger pump 3. The drive motor is a linear motor 4, with a simple structure. Compared with the technical solutions using a submersible screw pump or a submersible centrifugal pump and the corresponding drive motors, the use of the submersible plunger pump 3 and the linear motor 4 can better adapt to the complex downhole conditions and can better control the liquid output of the oil well. However, in other specific embodiments, the submersible pump can also be a submersible screw pump, and the drive motor is the corresponding screw motor; or the submersible pump is a submersible centrifugal pump, and the drive motor is the corresponding submersible motor (permanent magnet synchronous motor or three-phase squirrel-cage induction motor).

[0028] When producing oil from a single oil layer or conducting commingled production of two or more oil layers, the driving motor drives the submersible pump to operate for oil production. The packer 8 can separate the annulus between the casing and the tubing into a liquid outlet annulus 14 and a liquid inlet annulus 13. Among them, the liquid inlet annulus 13 corresponds to the oil production layer 12 and is connected to the casing hole 15, so that the formation fluid in the formation can directly enter the liquid inlet annulus 13. The liquid outlet annulus 14 does not correspond to the casing hole 15, and the formation fluid cannot enter the liquid outlet annulus 14 through the casing hole 15. The liquid inlet annulus 13 and the liquid outlet annulus 14 are connected through the liquid inlet 91, the flow-through channel and the liquid outlet 61, so that the formation fluid in the liquid inlet annulus 13 can flow into the liquid outlet annulus 14 to cool the driving motor. At the same time, the submersible pump can transport the liquid in the liquid outlet annulus to the wellhead. After the formation sand enters the liquid inlet annulus 13 along with the formation fluid, the formation sand will bury the liquid inlet 91, resulting in no formation fluid flowing out of the liquid outlet 61. At the same time, since the submersible pump is still continuously transporting the existing formation fluid in the liquid outlet annulus 14 to the wellhead, the formation fluid in the liquid outlet annulus 14 is continuously reduced, and then the speed of the formation fluid being transported by the submersible pump is continuously slowed down, resulting in abnormal wellhead liquid production. Thus, the staff can know that the sand control and anti-sticking production tubing string is abnormal and needs to be repaired. At this time, the formation sand only buries the liquid inlet 91 of the flow-through channel and does not bury the formation fluid inlets of the driving motor and the submersible pump. The length of the sand control and anti-sticking production tubing string buried by the sand is only more than one meter or several meters, and there will be no sand sticking phenomenon. The staff can easily lift out the sand control and anti-sticking production tubing string, thus avoiding major repair operations on the oil well. In particular, when the oil well is a horizontal well, the staff can lift out the sand control and anti-sticking production tubing string horizontally; when the oil well is a directional well with a large dogleg severity, the staff determines the method of lifting out the sand control and anti-sticking production tubing string according to the actual situation.

[0029] Specifically, when the wellhead liquid production is abnormal, the wellhead liquid production monitoring system will send an alarm to the staff, informing the staff that the oil well is abnormal. After receiving the alarm signal, the staff will repair the oil well. This part is the same as the prior art and will not be elaborated here.

[0030] As Figure 1 shown, in order to avoid the problem that the staff fails to repair the sand control and anti-sticking production tubing string in time, resulting in the need for major repair operations after the driving motor and the submersible pump are buried by sand, as a specific implementation manner, the flow-through structure further includes a safety joint 5. When the sand control and anti-sticking production tubing string is buried more severely, the safety joint 5 can be pulled off, so as to lift out a part of the tubing string connected to the end of the safety joint 5 close to the driving motor (in Figure 1 it is structures such as the driving motor, the submersible pump and the tubing 2 connected to the submersible pump), and then, through measures such as washing with a sleeve, lift out the other part of the tubing string on the side of the safety joint 5 away from the driving motor.

[0031] Of course, in other specific embodiments, the safety joint 5 may not be provided. In this case, the staff needs to quickly handle the alarm signal to avoid the situation where no one deals with the alarm signal and the sand control and sand sticking production tubing string with anomalies is not repaired, resulting in a long length of the sand control and sand sticking production tubing string being buried by sand.

[0032] As Figure 1 shown, in order to facilitate the removal of a part of the tubing string connected to one end of the safety joint 5 near the drive motor, as a specific embodiment, the safety joint 5 is located between the packer 8 and the drive motor, so that the safety joint 5 can be broken under the premise of not needing to release the packer 8, facilitating the removal of a part of the tubing string connected to one end of the safety joint 5 near the drive motor. However, in other specific embodiments, referring to Figure 1 shown, the packer 8 can also be located between the safety joint 5 and the drive motor. In this case, the packer 8 needs to be released first, and then the safety joint 5 is broken.

[0033] As Figure 1 shown, in order to better prevent sand, as a specific embodiment, a liquid inlet screen pipe 9 is connected to the side of the packer 8 away from the drive motor. The screen holes of the liquid inlet screen pipe 9 form the liquid inlet 91. Since the size of the screen holes is small, it can effectively prevent formation sand from flowing into the liquid inlet 91, thereby avoiding a large amount of formation sand from entering the liquid outlet annulus 14 and sand burying the drive motor and the submersible pump.

[0034] However, in other specific embodiments, referring to Figure 1 shown, the liquid inlet screen pipe 9 can also be replaced with a liquid inlet tubing 2 having a larger liquid inlet 91, and a filter screen is installed at the liquid inlet 91.

[0035] As Figure 1 shown, in order to further improve the sand control effect, as a specific embodiment, a liquid outlet screen pipe 6 is connected to the side of the packer 8 away from the liquid inlet screen pipe 9. The screen holes of the liquid outlet screen pipe 6 form the liquid outlet 61, thereby further reducing the amount of formation sand entering the liquid outlet annulus 14 and avoiding the drive motor and the submersible pump being sand buried by formation sand.

[0036] However, in other specific embodiments, referring to Figure 1 shown, the liquid outlet screen pipe 6 can also be replaced with a liquid outlet tubing 2 having a larger liquid outlet 61, and a filter screen is installed at the liquid outlet 61.

[0037] As Figure 1As shown, in order to prevent liquid backflow, as a specific implementation, the flow-through structure further includes a check valve 7. The flow channels in the liquid inlet screen pipe 9, the packer 8, the check valve 7, and the liquid outlet screen pipe 6 together constitute the flow-through channel, which has a simple structure and can avoid liquid backflow. During use, since the formation fluid in the liquid outlet annulus 14 is continuously pumped away by the submersible pump, the pressure of the formation fluid in the liquid outlet annulus 14 is relatively low. At the same time, the pressure of the formation fluid in the oil production layer 12 is relatively high. When the formation fluid in the liquid inlet annulus 13 enters the liquid inlet annulus 13 and the pressure of the formation fluid in the liquid inlet annulus 13 is greater than the pressure of the formation fluid in the liquid outlet annulus 14, the formation fluid in the liquid inlet annulus 13 will spontaneously flow into the liquid outlet annulus through the flow-through channel, thereby effectively utilizing the formation energy to transport the formation fluid from the liquid inlet annulus 13 to the liquid outlet annulus 14 and saving energy.

[0038] However, in other specific implementations, the check valve 7 may not be provided, and the flow-through channel is always in a normally open state. Since the pressure of the formation fluid in the liquid inlet annulus 13 is greater than the pressure of the formation fluid in the liquid outlet annulus 14, the formation fluid in the liquid inlet annulus 13 will still enter the liquid outlet annulus 14.

[0039] As Figure 1 shown, in order to conveniently achieve the sealing at the lower end of the pipe string and ensure the expandability of the pipe string, as a specific implementation, a plug 10 is connected to the end of the liquid inlet screen pipe 9 away from the packer 8, thereby achieving the sealing at the lower end of the pipe string; at the same time, when other parts need to be connected to the lower part of the liquid outlet screen pipe 6, the plug 10 can be removed to install other parts on the liquid inlet screen pipe 9.

[0040] However, in other specific implementations, referring to Figure 1 shown, the lower end of the liquid inlet screen pipe can also be closed. When the pipe string needs to be expanded, the original liquid inlet screen pipe with a closed lower end on the pipe string can be replaced with a liquid inlet screen pipe 9 with a connecting thread at the lower end.

[0041] In this embodiment, as Figure 1 shown, the tubing 2, the submersible plunger pump 3, the linear motor 4, the safety joint 5, the liquid outlet screen pipe 6, the check valve 7, the packer 8, the liquid inlet screen pipe 9, and the plug 10 are sequentially thread-connected. However, in other specific implementations, the submersible plunger pump 3 and the linear motor 4 can also be welded and fixed. In this embodiment, the connection method between each component is not limited as long as the adjacent components can be fixedly connected.

[0042] As Figure 1 shown, in order to simplify the structure, as a specific implementation, the sand prevention and sticking oil production pipe string further includes a cable 1 electrically connected to the drive motor and used to control the drive motor. The cable 1 can also supply power to the drive motor and transmit control signals to the drive motor, with a simple structure.

[0043] Referring toFigure 1 as shown, but in other specific embodiments, a wireless signal generating device for sending the driving motor status signal to the outside and a storage battery for powering the driving motor and the wireless signal generating device may also be provided on the sand control and sand sticking production tubing string. A charging cable 1 is connected to the storage battery, and the wireless signal generating device can also send the power information of the storage battery to facilitate the staff to charge the storage battery through the charging cable 1.

[0044] Of course, in other specific embodiments, with reference to Figure 1 as shown, a storage battery, a sensor for monitoring the working status of the driving motor, and a controller with a wireless signal generating device may also be provided on the sand control and sand sticking production tubing string. The controller uses the wireless signal generating device to send the information detected by the sensor. At this time, the storage battery powers the temperature sensor and the controller. Of course, in other specific embodiments, the controller and the sensor can also be powered through the cable 1, and the information detected by the sensor is transmitted through the cable 1.

[0045] Such as Figure 1 as shown, in order to avoid the shaking of the cable 1 and improve the service life of the cable 1, as a specific embodiment, a submersible pump is connected to the end of the driving motor far from the overcurrent structure, and a tubing 2 is connected to the end of the submersible pump far from the driving motor. The cable 1 is provided with a clip for clamping the cable 1 on the outer wall of the tubing 2, so as to avoid the friction between the cable 1 and the casing 11 and the tubing 2 when the cable 1 shakes, avoid the abrasion of the cable 1, and extend the service life of the cable 1.

[0046] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still make modifications to the technical solutions described in the foregoing embodiments without creative efforts, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A sand-blocking prevention oil production pipe string, comprising a submersible pump and a driving motor for driving the submersible pump, characterized in that: A flow structure is connected to the side of the driving motor away from the submersible pump. The flow structure includes a packer which is located on one side of all casing holes when in use and divides the casing annulus into a liquid outlet annulus and a liquid inlet annulus directly connected to the casing holes. The flow structure also includes a flow passage, a liquid inlet for connecting the flow passage and the liquid inlet annulus, and a liquid outlet for connecting the flow passage and the liquid outlet annulus. The submersible pump, the driving motor and the liquid outlet are located on one side of the packer, and the liquid inlet is located on the other side of the packer.

2. The sand-blocking oil production pipe string according to claim 1, characterized in that: The flow-through structure also includes a safety joint.

3. The sand-blocking oil production pipe string according to claim 2, characterized in that: The safety joint is located between the packer and the drive motor.

4. The sand-blocking oil production pipe string according to any one of claims 1 to 3, characterized in that: A liquid inlet screen is connected to the side of the packer away from the driving motor, and the screen holes of the liquid inlet screen constitute the liquid inlet.

5. The sand-blocking oil production pipe string according to claim 4, characterized in that: A liquid outlet screen is connected to the side of the packer away from the liquid inlet screen, and the screen holes of the liquid outlet screen constitute the liquid outlet.

6. The sand-blocking oil production pipe string according to claim 5, characterized in that: The flow structure also includes a check valve, and the flow channel in the liquid inlet screen, the packer, the check valve and the liquid outlet screen together constitute the flow channel.

7. The sand-blocking oil production pipe string according to claim 5, characterized in that: One end of the liquid inlet screen away from the packer is connected with a wire plug.

8. The sand-stuck oil production pipe string according to any one of claims 1 to 3, characterized in that: The sand-stuck oil production pipe string also includes a cable electrically connected to the drive motor and used for controlling the drive motor.

9. The sand-blocking oil production pipe string according to claim 8, characterized in that: One end of the driving motor away from the flow structure is connected to a submersible pump, and one end of the submersible pump away from the driving motor is connected to an oil pipe. The cable is provided with a clip for clamping the cable on the outer wall of the oil pipe.

10. The sand-blocking oil production pipe string according to any one of claims 1 to 3, characterized in that: One end of the driving motor away from the flow structure is connected with a submersible plunger pump, and the driving motor is a linear motor.

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