Reverse circulation jet pump capable of being thrown and fished and reverse circulation sand-carrying tubular column
By introducing a locking device into the reverse circulation jet pump, the locking problem between the pump core and the pump barrel was solved, achieving efficient sand carrying and simplifying pump inspection operations, thereby improving downhole operation efficiency and reducing costs.
Patent Information
- Application Number
- CN202423259946.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2025-10-24
- Estimated Expiration
- 2034-12-27
AI Technical Summary
In the existing technology, the positive circulation jet pump cannot meet the sand carrying requirements during the drainage process of high water cut wells, and the pump core of the reverse circulation jet pump is fixedly connected to the pump barrel. When inspecting and repairing the pump, the entire tubing string in the well needs to be pulled out, which is complicated and has low work efficiency.
Design a drop-and-retrieve reverse circulation jet pump with a locking device between the pump core and the pump barrel. The locking is achieved by the cooperation of the locking claw and the fixing groove. The pump core can be locked and unlocked in the well, simplifying the pump inspection and maintenance process.
It enables the pump core to be retrieved with simple operation without removing the tubing string from the well, improving sand carrying capacity and working efficiency, and reducing operating costs.
Smart Images
Figure CN223469239U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to oil and gas field downhole tool technical field, specifically, relate to a kind of fishing type reverse circulation jet pump and reverse circulation sand-carrying pipe column. BACKGROUND
[0002] Most of old oilfields in China were put into development in the 1970s and 1980s, and have entered the mid-late stage of high water-cut development. The water cut of oilfields is rising, and the production is declining seriously, and the stable production situation is severe. At present, rod pump, electric submersible pump, gas lift and jet pump technologies are mainly used to develop high water production wells at home and abroad. Among them, the rod pump has the problem of eccentric wear of rod and pipe, the electric submersible pump has poor heat dissipation, the motor cable is prone to failure, the maintenance cost is high, the gas lift method needs sufficient gas source, the operation cost is high, and the reservoir will be back-pressured, and even the wellbore fluid will be pressed into the formation. The above-mentioned process technologies have obvious shortcomings. The hydraulic jet pump has good application effect because of its small influence of gas lock and solid particles. However, the current positive circulation jet pump cannot meet the sand-carrying requirement in the liquid discharge process because of the large space of the oil jacket annulus and the slow flow rate. The pump core and pump barrel of the reverse circulation jet pump are fixedly connected, and when the pump is checked, repaired or replaced, the whole pipe string in the well needs to be pulled out, which is complicated and low in working efficiency. Therefore, it is necessary to design a fishing type reverse circulation jet pump which is simple to operate, high in working efficiency and strong in sand-carrying capacity. CONTENT OF THE UTILITY MODEL
[0003] The utility model aims to solve at least one of the above-mentioned deficiencies in the prior art. For example, one of the purposes of the utility model is to provide a fishing type reverse circulation jet pump which is simple to operate, strong in sand-carrying capacity and can pull out the pump core without pulling out the pipe string in the well. Another purpose of the utility model is to provide a reverse circulation sand-carrying pipe column which is high in working efficiency.
[0004] In order to achieve the above-mentioned purposes, the utility model provides a fishing type reverse circulation jet pump on one hand, which can include a pump core and a pump barrel. The pump barrel can include an upper joint and a lower joint, and the upper joint is connected with the lower joint. A fixed groove is formed in the radial direction inside the upper joint, and the fixed groove cooperates with a locking pawl to lock the pump core. A plurality of pump barrel through holes are radially distributed in the middle of the lower joint. The pump core as a whole can be locked inside the pump barrel. The pump core can include a fishing head, a locking pawl, a connecting sleeve, a diffuser pipe, a throat pipe, a nozzle and a valve body. The locking pawl is arranged in the circumferential direction of the fishing head and can rotate to be separated from the fixed groove. The fishing head is connected with the connecting sleeve. The diffuser pipe and the throat pipe can be arranged inside the connecting sleeve. The outlet end of the diffuser pipe is communicated with the inside of the fishing head. The inlet end of the diffuser pipe is communicated with the outlet end of the throat pipe. The valve body is arranged at the lower end of the connecting sleeve and connected with the connecting sleeve. The nozzle is arranged inside the valve body, and the outlet of the nozzle faces the inlet end of the throat pipe. A plurality of valve body through holes are radially distributed in the middle of the valve body, and the valve body through holes are communicated with the pump barrel through holes and the inside of the nozzle.
[0005] According to one or more exemplary embodiments of one aspect of the present application, a fixed groove can be formed in the radial direction inside the upper joint, and the fixed groove is configured to cooperate with the locking claw to lock the pump core.
[0006] According to one or more exemplary embodiments of one aspect of the present application, the inlet end of the diffuser pipe can be a tapered small-diameter end, and the outlet end can be a tapered large-diameter end.
[0007] According to one or more exemplary embodiments of one aspect of the present application, the inlet end of the throat pipe can be a streamline shape.
[0008] According to one or more exemplary embodiments of one aspect of the present application, the diameter of the outlet end of the throat pipe can be equal to the diameter of the inlet end of the diffuser pipe.
[0009] According to one or more exemplary embodiments of one aspect of the present application, the inside of the nozzle can be a conical shape, and the diameter of the nozzle inlet is greater than the diameter of the nozzle outlet.
[0010] According to one or more exemplary embodiments of one aspect of the present application, the diffuser pipe outlet end can be provided with a stop block configured to limit the axial movement of the diffuser pipe.
[0011] According to one or more exemplary embodiments of one aspect of the present application, a plurality of liquid suction holes are provided in the circumferential direction of the valve body, and the liquid suction holes penetrate the valve body in the axial direction of the valve body.
[0012] According to one or more exemplary embodiments of one aspect of the present application, a lip-shaped sealing ring can be provided outside the valve body.
[0013] According to one or more exemplary embodiments of one aspect of the present application, an O-shaped sealing ring can be provided between the connection end of the upper joint and the lower joint, an O-shaped sealing ring can be provided between the throat pipe and the connecting sleeve, and an O-shaped sealing ring can be provided between the connecting sleeve and the valve body.
[0014] Another aspect of the present application provides a reverse circulation sand-carrying pipe string, which can include the fishable reverse circulation jet pump described above.
[0015] Compared with the prior art, the beneficial effects of the present application include at least one of the following contents:
[0016] (1) The jet pump provided by the present application is designed with a locking device between the pump core and the pump barrel, which can keep the locking of the pump core and the pump barrel during the reverse circulation liquid discharge process.
[0017] (2) The sand-carrying pipe string provided by the present application has low operating cost and can solve the technical problem of drainage and production in high water-cut wells. BRIEF DESCRIPTION OF DRAWINGS
[0018] The above and other objects and / or characteristics of the present application will become more apparent by describing in detail the preferred embodiments thereof with reference to the attached drawings, wherein:
[0019] Figure 1 A schematic diagram of a pump barrel structure of an example embodiment is shown;
[0020] Figure 2 A schematic diagram of a pump core structure of the present application is shown;
[0021] Figure 3 A schematic diagram of a fishing type reverse circulation jet pump structure of the present application is shown;
[0022] Figure 4 A schematic diagram of Figure 3 A sectional view of part A-A is shown.
[0023] Explanation of main reference numerals:
[0024] 1 - upper joint, 2 - O-shaped sealing ring, 3 - lower joint, 4 - fishing head, 5 - locking claw, 6 - pin shaft, 7 - lip-shaped sealing ring, 8 - stop block, 9 - connecting sleeve, 10 - diffuser pipe, 11 - throat pipe, 12 - nozzle, 13 - valve body, 14 - valve body through hole, 15 - pump barrel through hole, 16 - liquid suction hole. DETAILED DESCRIPTION
[0025] Hereinafter, a fishing type reverse circulation jet pump and a reverse circulation sand carrying pipe column of the present application will be described in detail in conjunction with an example embodiment.
[0026] In the description of the present application, it should be understood that the positions or location relationships indicated by the terms "intermediate", "inner", "outer" and the like are based on the positions or location relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular position, be constructed and operated in a particular position, and therefore cannot be understood as limiting the present application.
[0027] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the term "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements. For those skilled in the art, the specific meaning of the above-mentioned terms in the present application can be understood according to the specific circumstances.
[0028] First example embodiment
[0029] The present example embodiment provides a fishing type reverse circulation jet pump.
[0030] Figure 1 A schematic diagram of the pump barrel structure of an exemplary embodiment is shown; Figure 2 Shows a schematic diagram of the pump core structure of the present utility model; Figure 3 The schematic diagram of the structure of the retractable reverse circulation jet pump of the present invention is shown; Figure 4 Shown Figure 3 The cross-sectional view of the AA part. Figures 1 to 4 The castable reverse circulation jet pump of this exemplary embodiment will be described.
[0031] In this exemplary embodiment, the castable reverse circulation jet pump mainly includes a pump core and a pump barrel, wherein Figure 1 As shown in or 3, the pump barrel may include an upper joint 1, an O-ring 2 and a lower joint 3. The upper end of the upper joint 1 is threadedly connected to other working pipe strings configured above; the lower end of the upper joint 1 is threadedly connected to the lower joint 3; the lower end of the lower joint 3 can also be threadedly connected to other working pipe strings configured below; the O-ring 2 is provided between the connecting ends of the upper joint 1 and the lower joint 3 to seal the upper joint 1 and the lower joint 3; a plurality of radially distributed pump barrel through holes 15 are provided in the middle of the lower joint 3, and the pump barrel through holes 15 are communicated with the oil casing annulus outwardly and with the valve body through holes inwardly.
[0032] like Figure 3 As shown in , the pump core as a whole can be locked inside the pump barrel, as shown in Figure 2 As shown in the figure, the pump core may include a fishing head 4, a locking claw 5, a connecting sleeve 9, a diffuser 10, a throat 11, a nozzle 12 and a valve body 13. The fishing head 4 is located at the top of the pump core and a fishing neck structure is provided inside the fishing head 4. When the pump core is fished, a special fishing tool can be used to fix it at the fishing neck to fish the pump core; the locking claw 5 is fixed to the middle outer part of the fishing head 4. The locking claw 5 can be arranged circumferentially around the fishing head 4 and can be rotated out of the fixed groove. The lower part of the fishing head 4 is threadedly connected to the connecting sleeve 9; a diffuser 10 and a throat 11 may be provided inside the connecting sleeve 9, with the outlet end of the diffuser 10 facing the fishing head 4, an annulus provided inside the fishing head 4, and the outlet end of the diffuser 10 communicating with the annulus inside the fishing head 4; the inlet end of the diffuser 10 communicating with the outlet end of the throat 11; a nozzle 12 may be provided between the connecting sleeve 9 and the valve body 13, specifically, the nozzle 12 may be provided inside the connecting end of the connecting sleeve 9 and the valve body 13, with the outlet of the nozzle 12 facing the inlet end of the throat 11; the valve body 13 is provided at the lower end of the connecting sleeve 9 and is threadedly connected to the connecting sleeve 9. The nozzle 12 is provided inside the valve body 13 and the outlet of the nozzle 12 faces the inlet end of the throat 11; a plurality of radially distributed valve body through holes 14 are provided in the middle of the valve body 13, such as Figure 3As shown in Figs. 4 or 3, the outer end of the valve body through hole 14 is directed to the pump cylinder through hole 15; the inner end of the valve body through hole 14 is communicated with the inside of the nozzle 12, that is, the valve body through hole 14 communicates the pump cylinder through hole 15 with the inside of the nozzle 12, and the liquid enters the inside of the nozzle 12 from the pump cylinder through hole 15 through the valve body through hole 14. As shown in Fig. 4, Figure 4 As shown in Fig. 4, a plurality of liquid suction holes 16 are arranged in the circumferential direction of the valve body 13. Figure 2 As shown in Figs. 4 or 3, the liquid suction hole 16 penetrates the valve body 13 in the axial direction of the valve body 13. One end of the liquid suction hole 16 is opened to the connecting sleeve 9, and the other end is opened to the bottom of the valve body 13, so that the liquid suction hole 16 can communicate the inside of the valve body 13 with the bottom of the well.
[0033] In the exemplary embodiment, as shown in Fig. 4, Figure 2 As shown in Figs. 4 or 3, the inlet end of the diffuser pipe 10 can be a small-diameter tapered end; the outlet end can be a large-diameter tapered end, and the diffuser pipe 10 has an overall inverted V-shaped structure. This structure can convert part of the kinetic energy of the liquid into potential energy. During the liquid flowing from the inlet end to the outlet end of the diffuser pipe 10, the liquid flow velocity decreases and the liquid pressure increases as the fluid passage diameter increases, which is beneficial to the discharge of the liquid to the ground.
[0034] In the exemplary embodiment, as shown in Fig. 4, Figure 2 As shown in Figs. 4 or 3, the inlet and outlet ends of the throat pipe 11 can be streamlined, which can reduce the fluid resistance and the liquid erosion of the inlet end of the throat pipe. The diameter of the outlet end of the throat pipe 11 can be equal to the diameter of the inlet end of the diffuser pipe, so as to reduce the erosion between the outlet end of the throat pipe 11 and the inlet end of the diffuser pipe 10. The diameter of the inlet end of the throat pipe 11 can be larger than the diameter of the outlet end.
[0035] In the exemplary embodiment, as shown in Fig. 4, Figure 2 As shown in Figs. 4 or 3, the inside of the nozzle 12 can be designed as a conical structure, and the diameter of the inlet of the nozzle 12 (i.e., the communication part between the nozzle 12 and the valve body through hole 14) is larger than the diameter of the outlet of the nozzle 12. After the liquid enters the inside of the nozzle 12 from the valve body through hole 14, the diameter of the inside of the nozzle 12 sharply decreases in the upward direction of the liquid flow, and the liquid flow velocity increases after the liquid passes through the outlet of the nozzle 12. The liquid with high flow velocity at the outlet of the nozzle 12 can suck the liquid at the bottom of the jet pump from the liquid suction hole and enter the inside of the throat pipe 11. After the liquid and the formation liquid in the throat pipe 11 are mixed uniformly, they flow into the diffuser pipe 10. During the process of flowing through the diffuser pipe 10, the liquid flow velocity decreases and the liquid pressure increases, so that the liquid is lifted to the ground by the fluid pressure.
[0036] In the exemplary embodiment, as shown in Fig. 4, Figure 2As shown in FIG3 , a stopper 8 may be provided at the outlet end of the diffuser 10, and the stopper 8 is configured to limit the axial movement of the diffuser 10. Preferably, the stopper 8 may be fixed between the fishing head 4 and the connecting sleeve 9, so that the movement of the stopper 8 can be limited.
[0037] In this exemplary embodiment, Figure 1 As shown in FIG3 , a fixing groove may be provided in the radial direction of the upper joint 1 . Figure 3 As shown in , the fixing groove is configured to cooperate with the locking claw 5. When the pump core is delivered into the pump barrel, the locking claw 5 can be fixed in the fixing groove, thereby locking the pump core. For example, when the pump core is delivered, the pump barrel is connected to the downhole drainage pipe string and lowered into the well along with the pipe string. After the pump barrel is lowered into the designed position, a steel wire operation can be used to connect the jar, the pump core delivery tool and the pump core and lower them into the pump barrel. The jar is activated to drive the pump core delivery tool and the pump core into the pump barrel, completing the locking of the locking claw 5 and the fishing neck of the fishing head. At this time, the locking claw 5 is locked in the fixing groove. After the pump core and the pump barrel are locked, the steel wire operation is used to lift the jar and the pump core delivery tool, and the pump core delivery tool and the pump barrel are released, completing the pump core delivery.
[0038] For another example, when retrieving a pump core, a wireline operation can be used to connect the jar, the pump core delivery tool, and the pump core unlocking tool. The pump core unlocking tool is lowered into the pump barrel, activating the jar. The jar pushes the pump core unlocking tool into the position of the pump core's locking claw 5. The pump core unlocking tool then rotates the locking claw 5, disengaging the locking claw 5 from the fixed groove, thereby unlocking the pump core from the pump barrel. At the same time, the pump core delivery tool cooperates with the fishing neck inside the fishing head 4. The wireline operation drives the pump core delivery tool and the pump core to the wellhead together, thereby retrieving the pump core.
[0039] In this exemplary embodiment, Figure 2 As shown in Figure 3, the pump core may be provided with a pin 6 at the fixed end of the locking claw 5. The locking claw 5 is rotatably connected to the fishing head 4 with the pin 6 as the base point. When the pump core is delivered into the pump barrel, the pin 6 can be rotated to adjust the position of the locking claw 5 to ensure that the locking claw can be fixed in the fixed groove.
[0040] In this exemplary embodiment, Figure 2As shown in Figs. 3 and 4, the upper end and the lower end of the valve body 13 can be provided with a lip seal 7. Here, the upper end of the valve body 13 refers to the end connected with the connecting sleeve 9, and the lower end of the valve body 13 refers to the end facing the bottom of the well. The number of the lip seals 7 on the upper end of the valve body 13 is different from that on the lower end of the valve body 13. For example, three lip seals 7 can be provided on the upper end of the valve body 13, and four lip seals 7 can be provided on the lower end of the valve body 13. Since the pump core needs to be delivered into the pump barrel, the sealing requirements of the upper end and the lower end of the valve body 13 are higher. The upper end and the lower end of the valve body 13 are provided with the lip seals 7, which are more durable than the ordinary O-shaped seals. During the delivery of the pump core into the pump barrel, the lower end seal first contacts the inside of the pump barrel, and the lower seal is more likely to be damaged than the upper seal. Therefore, the lower end of the valve body 13 can be provided with more lip seals 7.
[0041] In the present exemplary embodiment, as shown in Fig. 1, Figure 1 As shown in Figs. 3 and 4, the upper end and the lower end of the valve body 13 can be provided with a lip seal 7. Here, the upper end of the valve body 13 refers to the end connected with the connecting sleeve 9, and the lower end of the valve body 13 refers to the end facing the bottom of the well. The number of the lip seals 7 on the upper end of the valve body 13 is different from that on the lower end of the valve body 13. For example, three lip seals 7 can be provided on the upper end of the valve body 13, and four lip seals 7 can be provided on the lower end of the valve body 13. Since the pump core needs to be delivered into the pump barrel, the sealing requirements of the upper end and the lower end of the valve body 13 are higher. The upper end and the lower end of the valve body 13 are provided with the lip seals 7, which are more durable than the ordinary O-shaped seals. During the delivery of the pump core into the pump barrel, the lower end seal first contacts the inside of the pump barrel, and the lower seal is more likely to be damaged than the upper seal. Therefore, the lower end of the valve body 13 can be provided with more lip seals 7. Figure 2 As shown in Figs. 3 and 4, the upper end and the lower end of the valve body 13 can be provided with a lip seal 7. Here, the upper end of the valve body 13 refers to the end connected with the connecting sleeve 9, and the lower end of the valve body 13 refers to the end facing the bottom of the well. The number of the lip seals 7 on the upper end of the valve body 13 is different from that on the lower end of the valve body 13. For example, three lip seals 7 can be provided on the upper end of the valve body 13, and four lip seals 7 can be provided on the lower end of the valve body 13. Since the pump core needs to be delivered into the pump barrel, the sealing requirements of the upper end and the lower end of the valve body 13 are higher. The upper end and the lower end of the valve body 13 are provided with the lip seals 7, which are more durable than the ordinary O-shaped seals. During the delivery of the pump core into the pump barrel, the lower end seal first contacts the inside of the pump barrel, and the lower seal is more likely to be damaged than the upper seal. Therefore, the lower end of the valve body 13 can be provided with more lip seals 7.
[0042] In addition, as shown in Fig. 1, Figure 3 As shown in Figs. 3 and 4, the upper end and the lower end of the valve body 13 can be provided with a lip seal 7. Here, the upper end of the valve body 13 refers to the end connected with the connecting sleeve 9, and the lower end of the valve body 13 refers to the end facing the bottom of the well. The number of the lip seals 7 on the upper end of the valve body 13 is different from that on the lower end of the valve body 13. For example, three lip seals 7 can be provided on the upper end of the valve body 13, and four lip seals 7 can be provided on the lower end of the valve body 13. Since the pump core needs to be delivered into the pump barrel, the sealing requirements of the upper end and the lower end of the valve body 13 are higher. The upper end and the lower end of the valve body 13 are provided with the lip seals 7, which are more durable than the ordinary O-shaped seals. During the delivery of the pump core into the pump barrel, the lower end seal first contacts the inside of the pump barrel, and the lower seal is more likely to be damaged than the upper seal. Therefore, the lower end of the valve body 13 can be provided with more lip seals 7. Figure 2
[0043] Second exemplary embodiment
[0044] The present exemplary embodiment provides a reverse circulation sand-carrying pipe string, which mainly comprises the fishable reverse circulation jet pump of the first exemplary embodiment.
[0045] The method for delivering the pump core of the fishable reverse circulation jet pump can comprise the following steps: connecting the pump barrel with the well drainage pipe string, and lowering the pipe string into the well. After the pump barrel is lowered to the designed position, the steel wire operation is used to connect the jar, the pump core delivery special tool and the pump core, and the pump core is lowered into the pump barrel. The jar drives the pump core delivery special tool and the pump core into the pump barrel, and is locked with the internal fixing groove of the upper joint of the pump barrel, thereby realizing the locking of the pump core and the pump barrel. After the pump core and the pump barrel are locked, the steel wire operation is used to lift the jar and the pump core delivery special tool. The pump core delivery special tool is separated from the pump barrel, and the pump core is delivered.
[0046] The method of the reverse circulation drainage of the fishing type reverse circulation jet pump can comprise: after the pump core is sent, the ground pump truck injects power fluid from the oil jacket annulus, the power fluid enters the inside of the nozzle in the valve body hole from the pump barrel through hole, the power fluid is pressurized by the nozzle and is sprayed from the nozzle outlet, so that the relative negative pressure is formed at the nozzle outlet, the well bottom liquid is sucked from the valve body through hole, and the well bottom liquid and the power fluid at the nozzle outlet are mixed together in the throat pipe and are sprayed to the ground through the diffusion pipe.
[0047] The method of the fishing of the pump core of the fishing type reverse circulation jet pump can comprise: connecting the jar, the pump core sending special tool and the pump core unlocking tool by wireline operation, lowering the pump core unlocking tool into the pump barrel, exciting the jar, pushing the pump core unlocking tool into the locking jaw position of the pump core by the jar, pushing the locking jaw to rotate by the pump core unlocking tool, separating the pump core locking jaw from the pump barrel fixing groove, and unlocking the pump core and the pump barrel. Meanwhile, the pump core sending special tool is matched with the fishing neck inside the pump core fishing head, the pump core sending special tool and the pump core are lifted to the wellhead by wireline operation, and the fishing of the pump core is realized.
[0048] In conclusion, the advantages of the fishing type reverse circulation jet pump and the reverse circulation sand-carrying pipe column can comprise at least one of the following contents:
[0049] (1) The jet pump is simple to operate and low in maintenance cost.
[0050] (2) The jet pump can meet the sand-carrying requirement of the drainage process and is high in operation efficiency.
[0051] (3) The jet pump does not need to be pulled out of the pipe column in the well, the pump core can be pulled out by wireline operation, and the operation is simple.
[0052] (4) The sand-carrying pipe column operation is convenient and good in application effect.
[0053] Although the fishing type reverse circulation jet pump and the reverse circulation sand-carrying pipe column of the present application have been described above by combining the exemplary embodiments, those skilled in the art should understand that various modifications and changes can be made to the exemplary embodiments of the present application without departing from the spirit and scope defined by the claims.
Claims
1. A fishable reverse circulation jet pump, characterized by, The jet pump comprises a pump core and a pump barrel, The pump barrel comprises an upper joint and a lower joint, the upper joint and the lower joint are connected, a fixing groove is arranged in the radial direction inside the upper joint, the fixing groove is matched with a locking claw, and the pump core can be locked; a plurality of pump barrel through holes are arranged in the radial direction in the middle of the lower joint; The pump core can be locked inside the pump barrel as a whole, the pump core comprises a fishing head, a locking claw, a connecting sleeve, a diffusion pipe, a throat pipe, a nozzle and a valve body, the locking claw is arranged in the circumferential direction of the fishing head and can be rotated to be separated from the fixing groove; the fishing head is connected with the connecting sleeve at the lower part; the diffusion pipe and the throat pipe are arranged inside the connecting sleeve, the outlet end of the diffusion pipe is communicated with the inside of the fishing head; the inlet end of the diffusion pipe is communicated with the outlet end of the throat pipe; the valve body is arranged at the lower end of the connecting sleeve and is connected with the connecting sleeve, the nozzle is arranged inside the valve body and the outlet of the nozzle is directed to the inlet end of the throat pipe; a plurality of valve body through holes are arranged in the radial direction in the middle of the valve body, the valve body through holes are communicated with the pump barrel through holes and the inside of the nozzle.
2. The fishable reverse circulation jet pump of claim 1, wherein, The inlet end of the diffusion pipe is a small-diameter tapered end, and the outlet end is a large-diameter tapered end.
3. The fishable reverse circulation jet pump of claim 1, wherein, The inlet end of the throat pipe is a streamline shape.
4. The fishable reverse circulation jet pump of claim 1, wherein, The diameter of the outlet end of the throat pipe is equal to the diameter of the inlet end of the diffusion pipe.
5. The fishable reverse circulation jet pump of claim 1, wherein, The inside of the nozzle is tapered, the diameter of the inlet of the nozzle is larger than the diameter of the outlet of the nozzle.
6. The fishable reverse circulation jet pump of claim 1, wherein, The diffusion pipe outlet end is provided with a stop block configured to limit the axial movement of the diffusion pipe.
7. The fishable reverse circulation jet pump of claim 1, wherein, A plurality of liquid suction holes are arranged in the circumferential direction of the valve body, and the liquid suction holes penetrate the valve body in the axial direction of the valve body.
8. The fishable reverse circulation jet pump of claim 1, wherein, A lip-shaped sealing ring is arranged outside the valve body.
9. The fishable reverse circulation jet pump of claim 1, wherein, An O-shaped sealing ring is arranged between the connecting ends of the upper joint and the lower joint; an O-shaped sealing ring is arranged between the throat pipe and the connecting sleeve; and an O-shaped sealing ring is arranged between the connecting sleeve and the valve body.
10. An anti-circulation sand-carrying string, characterized in that, The reverse circulation sand-carrying pipe column comprises the fishable reverse circulation jet pump according to any one of claims 1-9.