Mechanical sand bailing device and sand bailing method for treating solid-phase sediments of horizontal well

Abstract

The invention discloses a mechanical sand bailing device and a sand bailing method for treating solid-phase sediments of a horizontal well, and relates to the technical field of sand bailing devices.The mechanical sand bailing device comprises a sand bailing mechanism and a buffer anchoring mechanism; the bailing mechanism comprises an upper joint, a sand pumping hydraulic cylinder and a bailing piston; the upper connector communicates with one side of the sand pumping hydraulic cylinder, the sand bailing piston communicates with the other side of the sand pumping hydraulic cylinder, and a sand storage cavity is formed in the sand pumping hydraulic cylinder. A sand setting one-way valve is connected between the upper connector and the sand storage cavity, and a sand pumping one-way valve is connected between the sand pumping piston and the sand storage cavity. The buffer anchoring mechanism comprises an anchoring piston, an anchoring shell and a guide head; the guide head is connected to one side of the anchoring shell and used for being inserted into gravel. A plurality of anchoring slips are connected to the peripheral side of the anchoring shell in a sliding manner; one side of the anchoring piston is slidably connected into the anchoring shell, and the other end of the anchoring piston is fixedly connected with the sand bailing piston. A reset piston is connected into the anchoring shell in a sliding mode and enables the anchoring slip to be unlocked from the inner wall of the casing pipe.

Description

Technical Field

[0001] This application belongs to the technical field of sand fishing devices, and particularly relates to a mechanical sand fishing device and a sand fishing method for treating solid-phase sediments in horizontal wells. Background Art

[0002] The development of coalbed methane mainly focuses on horizontal wells. Compared with vertical wells and ordinary directional wells, horizontal wells can more effectively conduct the fractures of coal reservoirs, significantly enhance the gas and water diversion capabilities in the well, increase the single-well production, and improve the recovery rate of coalbed methane. However, with the increase of the production and gas extraction years, solid-phase substances such as fracturing sand, sediment, and coal ash in the production layer gradually enter the production casing through the fracturing holes. Over time, solid-phase particles gradually accumulate in the entire production casing, ultimately leading to the blockage of the formation gas outlet channel and seriously affecting the production efficiency.

[0003] Currently, in order to remove the accumulated solid-phase substances in the horizontal well section and improve the gas production efficiency of old wells, the industry mainly adopts high-pressure hydraulic jet sand washing measures, that is, using a drilling rig to lower the operation string to the position where the sand deposition encounters resistance. A special "drill bit" is connected to the end of the operation string, and a pump truck is connected to the wellhead to start the pump. The sediments are washed out of the wellbore by hydraulic scouring. If relatively hard solid-phase substances are encountered, the string is rotated or lifted and lowered to drill out the sediments. However, since coalbed methane mainly produces gas under negative pressure, that is, it is necessary to drain water to reduce the formation pressure system so that the associated gas in the coalbed can be released. Hydraulic jet sand washing requires a large amount of cleaning fluid and a professional drilling rig, which not only has high costs, but also the liquid in the operation process raises the formation pressure coefficient again, and will also increase the later recovery cost; moreover, the hydraulic sand washing cleaning fluid is a chemical agent, which poses a certain pollution risk to the surrounding environment. Summary of the Invention

[0004] This application provides a mechanical sand fishing device and a sand fishing method for treating solid-phase sediments in horizontal wells to solve the problems in the above technical problems that hydraulic jet sand washing requires a large amount of cleaning fluid and a professional drilling rig, the liquid raises the formation pressure coefficient again, and the cleaning fluid is a chemical agent, which poses a certain pollution risk to the surrounding environment.

[0005] The technical solution adopted in this application is as follows:

[0006] A mechanical sand fishing device for treating solid-phase sediments in horizontal wells includes a sand fishing mechanism and a buffer anchoring mechanism;

[0007] The sand fishing mechanism includes an upper joint, a sand pumping cylinder, and a sand fishing piston; the upper joint is connected to one side of the sand pumping cylinder, the sand fishing piston is connected to the other side of the sand pumping cylinder, and a sand storage cavity is formed in the sand pumping cylinder; a sediment check valve is connected between the upper joint and the sand storage cavity, and a sand pumping check valve is connected between the sand pumping piston and the sand storage cavity; the sand pumping piston has a sand fishing channel for connecting the casing with the inner cavity of the sand pumping piston, and a sand passing channel for connecting the inner cavity of the sand pumping piston with the sand storage cavity;

[0008] A buffer anchoring mechanism includes an anchoring piston, an anchoring housing, and a guiding head; the guiding head is connected to one side of the anchoring housing for inserting into sand and gravel; a plurality of anchoring slips are slidably connected to the circumferential side of the anchoring housing; one side of the anchoring piston is slidably connected inside the anchoring housing, and the other end is fixedly connected to the sand fishing piston; a return piston is slidably connected inside the anchoring housing, and the return piston is connected with a buffer mechanism, and the buffer mechanism is configured to: when the sand fishing piston pushes the return piston to move so that the anchoring slips protrude outwards to lock with the inner wall of the casing, the buffer mechanism can absorb energy; when the sand fishing is completed, the buffer mechanism can release energy to push the return piston to reset, so that the anchoring slips are unlocked from the inner wall of the casing.

[0009] A mechanical sand fishing device for treating solid-phase sediments in a horizontal well of the present application further has the following additional technical features:

[0010] There are a first cavity and a second cavity separated from each other inside the anchoring housing;

[0011] An anchoring piston and a return piston are slidably connected inside the first cavity. A high-pressure buffer air chamber is formed between one side of the return piston and the anchoring piston, and the anchoring piston compresses the high-pressure buffer air chamber to push the return piston to move; a liquid storage chamber is formed inside the first cavity on the other side of the return piston.

[0012] The buffer mechanism includes an elastic liquid storage member, a first connecting pipe, and a second connecting pipe. The elastic liquid storage member is arranged inside the second cavity, and the elastic liquid storage member is communicated with the liquid storage chamber through the first connecting pipe and the second connecting pipe. The liquid in the liquid storage chamber flows to the elastic liquid storage member through the first connecting pipe, and the liquid in the elastic liquid storage member flows back to the liquid storage chamber through the second connecting pipe.

[0013] A one-way throttle valve group is connected to the first connecting pipe to prevent the liquid from flowing back into the liquid storage chamber from the elastic liquid storage member; a timing valve group is connected to the second connecting pipe to control the duration of the liquid flowing back into the liquid storage chamber from the elastic liquid storage member.

[0014] The buffer mechanism further includes a return spring arranged inside the first cavity; one end of the return spring is abutted and connected to the return piston, and the other end of the return spring is abutted and connected to the inner wall of the liquid storage chamber.

[0015] The anchoring housing includes an anchoring cylinder cap, an anchoring cylinder body, and a body outer shell; the anchoring cylinder cap is connected to the side of the anchoring cylinder body facing the sand pumping cylinder, and the body outer shell is connected between the anchoring cylinder body and the guiding head; a support rod is slidably connected inside the body outer shell, and the piston rod of the return piston sequentially passes through the liquid storage chamber, the second cavity to the inside of the body outer shell and is connected to the support rod.

[0016] The support rod adopts a variable diameter structure. The small-diameter end of the support rod faces the guiding head side, and the large-diameter end of the support rod is fixedly connected to the return piston;

[0017] A plurality of anchor slips are slidably connected to the peripheral side of the body housing, and a plurality of sliding bearings are connected between the anchor slips and the support rod, such that the anchor slips are configured to:

[0018] Have an initial position in contact with the outer periphery of the small-diameter end of the support rod, and when the reset piston moves to drive the support rod to move toward the guide head side, the large-diameter end of the support rod contacts the anchor slips, causing the anchor slips to protrude radially outward and abut against the inner wall of the casing at the locked position.

[0019] The upper joint is provided with a water outlet hole communicating with the inner cavity of the upper joint, and a filtering device is connected between the upper joint and the sand pumping cylinder;

[0020] On the side of the sand fishing piston outside the sand pumping cylinder, there is also a step surface abutting against the sand pumping cylinder to limit the movement of the sand pumping cylinder along the sand fishing piston, and after the sand pumping cylinder is pressed down to abut against the sand fishing piston, it can push the sand fishing piston to move;

[0021] When the sand pumping cylinder is lifted, a negative pressure is formed in the sand storage cavity, causing the sediment check valve to close and the sand pumping check valve to open. The liquid and sand pass through the sand fishing channel, through the inner cavity of the sand fishing piston, and into the sand storage cavity through the sand passing channel; when the sand pumping cylinder is pressed down, the sand storage cavity is compressed, the sand pumping check valve closes, the sediment check valve opens, and the sand in the sand storage cavity is stored in the sand storage cavity under the blocking action of the filtering device, and the liquid flows out through the water outlet hole.

[0022] This application also relates to a method for fishing sand from solid-phase sediments in horizontal wells. Based on the above-mentioned mechanical sand fishing device for treating solid-phase sediments in horizontal wells, the specific steps include:

[0023] S1: Connect the upper joint to the end of the pipe string and lower the sand fishing device into the casing so that the sand fishing device extends into the horizontal section of the horizontal well;

[0024] S2: When the guide head touches the solid-phase material, lift the sand fishing device and then quickly hammer it down so that the guide head inserts into the sediment;

[0025] S3: Press down the pipe string, apply pressure to the sand pumping cylinder through the upper joint, the sand pumping cylinder pushes the sand fishing piston to move toward the guide head side, and then pushes the reset piston and the support rod to move, so that the support rod pushes the anchor slips to protrude outward and abut against the inner wall of the casing, locking the buffer mechanism to the casing;

[0026] S4: Lift the pipe string upward, a negative pressure is formed in the sand storage cavity of the sand pumping cylinder, causing the sand pumping check valve to open and the sediment check valve to close. The liquid and solid substances in the annulus between the casing and the sand fishing device pass through the sand fishing channel and into the sand storage cavity through the inner cavity of the sand fishing piston;

[0027] S5: Press down the pipe string. The sand storage cavity in the sand pumping cylinder is compressed, causing the sand pumping check valve to close and the sediment sand check valve to open. The liquid in the sand storage cavity is discharged through the water outlet hole of the upper joint. Take out the sand fishing device to clean the sand and gravel in the sand storage cavity, and then repeat the sand fishing process.

[0028] The specific steps of step S3 include:

[0029] The sand fishing piston moves towards the guide head side. The sand fishing piston compresses the gas in the high-pressure buffer air chamber, driving the reset piston to move towards the guide head side.

[0030] Compress the liquid in the liquid storage cavity into the elastic liquid storage member for energy storage. After pressing down for a period of time, when the pressure in the liquid storage cavity is balanced with the pressure in the elastic liquid storage member, the liquid stops flowing.

[0031] The reset piston pushes the support rod to move, causing the anchoring slip to gradually abut against the large-diameter end side from the small-diameter end side of the support rod, so that the anchoring slip protrudes radially outward along the body shell to the locking position where it abuts against the inner wall of the casing.

[0032] The specific steps of step S5 include:

[0033] Press down the pipe string. The sand storage cavity in the sand pumping cylinder is compressed, causing the sand pumping check valve to close and the sediment sand check valve to open. The solids in the sand storage cavity are retained in the sand storage cavity due to the filtering device provided between the upper joint and the sand storage cavity, and the liquid is discharged through the water outlet hole of the upper joint to the annulus.

[0034] By opening the timing valve group, the liquid in the elastic liquid storage member flows back to the liquid storage cavity. Under the pushing action of the return spring and the liquid in the liquid storage cavity, the reset piston is reset.

[0035] The reset piston drives the support member to move away from the guide head side, causing the anchoring slip to gradually abut against the small-diameter end side of the support rod from the large-diameter end side of the support rod, so that the anchoring slip moves radially inward along the body shell to the initial position, realizing the unlocking between the sand fishing device and the casing.

[0036] Lift the pipe string to take out the sand fishing device from the casing and clean the sand and gravel in the sand storage cavity.

[0037] Repeat the sand fishing process until the cleaning is completed.

[0038] Due to the adoption of the above technical solutions, the beneficial effects obtained by this application are:

[0039] 1. A mechanical sand fishing device for treating solid-phase sediments in horizontal wells of the present application includes a sand fishing mechanism and a buffer anchoring mechanism; the sand fishing mechanism realizes the fishing of sand and liquid in the casing annulus part, and the buffer anchoring mechanism is used to be fixed in the rock so that the sand fishing device can be fixed inside the casing to prevent the position movement during the sand fishing process from affecting the sand fishing work;

[0040] The sand fishing mechanism includes an upper joint, a sand pumping liquid cylinder and a sand fishing piston; the upper joint is connected to one side of the sand pumping liquid cylinder, the sand fishing piston is connected to the other side of the sand pumping liquid cylinder, and a sand storage cavity is formed inside the sand pumping liquid cylinder; a sediment one-way valve is connected between the upper joint and the sand storage cavity, and a sand pumping one-way valve is connected between the sand pumping piston and the sand storage cavity; the sand pumping piston has a sand fishing channel for connecting the casing and the inner cavity of the sand pumping piston, and a sand passing channel for connecting the inner cavity of the sand pumping piston and the sand storage cavity; the upper joint can be fixedly connected to the pipe string, and by lifting the pipe string, the sand pumping liquid cylinder can be lifted, so that the volume of the sand storage cavity increases to form a negative pressure, the sediment one-way valve is closed, and the sand pumping one-way valve is opened, so that sand and liquid enter the sand storage cavity through the sand fishing channel, the inner cavity of the sand pumping piston and the sand passing channel, and then the pipe string is pressed down to open the sediment one-way valve and close the sand pumping one-way valve. The sand is blocked in the sand storage cavity due to the filtering device, and the liquid in the sand storage cavity can flow back to the casing through the upper joint, thus realizing the sand fishing operation; in the present application, by lifting and pressing the pipe string, the sand fishing mechanism can be operated to realize the fishing of sand in the casing. The operation is simple and stable, without using a large amount of traditional cleaning liquid for hydraulic sand washing, avoiding the pollution of chemical agents in the cleaning liquid of hydraulic sand washing to the environment, reducing the supporting use of the drilling rig, thereby reducing the equipment investment and use, reducing the operation space, and reducing the operation cost.

[0041] 2. As a preferred embodiment of the present application, the anchor housing has a first cavity and a second cavity separated from each other; an anchor piston and a return piston are slidably connected in the first cavity, and a high-pressure buffer air chamber is formed between one side of the return piston and the anchor piston. The anchor piston compresses the high-pressure buffer air chamber to push the return piston to move; a liquid storage cavity is formed in the first cavity on the other side of the return piston.

[0042] The purpose of separating the anchor liquid cylinder body into two independent chambers is that the first cavity can have a liquid storage cavity for storing liquid, and the second cavity can accommodate the elastic liquid storage member of the buffer mechanism. In this way, separating the liquid storage cavity from the buffer mechanism can lock the energy of the liquid storage cavity and the buffer mechanism in their respective regions, and realize the absorption and release of the energy of the buffer mechanism by means of connection or disconnection;

[0043] The high-pressure buffer gas chamber between the reset piston and the anchoring piston is sealed by rubber rings between the anchoring piston and the anchoring cylinder block and between the reset piston and the anchoring cylinder block during assembly at atmospheric pressure, so that the gas in the high-pressure buffer gas chamber is higher than atmospheric pressure. This gas is used to prevent vacuum pumping between the reset piston and the anchoring piston when the anchoring piston and the reset piston have relative displacement.

[0044] 3. As a preferred embodiment of the present application, the support rod adopts a variable-diameter structure. The small-diameter end of the support rod faces the guide head side, and the large-diameter end of the support rod is fixedly connected to the reset piston. A plurality of anchoring slips are slidably connected to the peripheral side of the body housing, and a plurality of sliding bearings are connected between the anchoring slips and the support rod.

[0045] The initial position of the anchoring slip corresponds to the small-diameter end of the support rod. When the support rod moves to the right, the contact between the support rod and the anchoring slip gradually changes from the small-diameter end of the support rod to the large-diameter end of the support rod, so that the anchoring slip moves radially from the groove of the body housing to the outside of the body housing, protruding from the peripheral surface of the body housing. At this time, the anchoring slip abuts and connects between the inner wall of the casing and the outer peripheral surface of the body housing, so that the buffer anchoring mechanism is locked and connected to the casing, thereby realizing the stable connection of the sand fishing device in the casing and facilitating the next sand fishing work. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation to the present application. In the drawings:

[0047] Figure 1 is a schematic structural diagram of a mechanical sand fishing device for treating solid-phase sediments in horizontal wells under an embodiment of the present application;

[0048] Figure 2 is a schematic structural diagram of the sand fishing mechanism of a mechanical sand fishing device for treating solid-phase sediments in horizontal wells under an embodiment of the present application;

[0049] Figure 3 is a schematic structural diagram of the buffer anchoring mechanism of a mechanical sand fishing device for treating solid-phase sediments in horizontal wells under an embodiment of the present application;

[0050] Figure 4 is Figure 1 the cross-sectional view at A-A in

[0051] Figure 5 is Figure 2 the structural diagram of the sliding protrusion of the anchoring slip and the peripheral surface of the body housing in

[0052] In the figure,

[0053] 1. Sand fishing mechanism; 11. Upper joint; 12. Sand pumping cylinder; 13. Sand fishing piston;

[0054] 2. Buffer and anchoring mechanism; 21. Anchoring piston; 22. Anchoring housing; 221. Anchoring cylinder cap; 222. Anchoring cylinder body; 223. Body housing; 23. Guide head;

[0055] 3. First cavity; 4. Second cavity; 5. Sand storage cavity; 6. Submerged sand check valve; 7. Sand pumping check valve; 8. Reset piston; 9. High-pressure buffer air chamber; 10. Liquid storage cavity;

[0056] 14. Buffer mechanism; 141. Elastic liquid storage member; 142. First connecting pipe; 143. Second connecting pipe; 144. Reset spring;

[0057] 15. One-way throttle valve group; 16. Timing valve group; 17. Support rod; 18. Small-diameter end; 19. Large-diameter end; 20. Anchoring slip; 24. Water outlet hole; 25. Filter device; 26. Sand fishing channel; 27. Sand passing channel. Detailed implementation mode

[0058] In order to more clearly illustrate the overall concept of the present application, the following will be described in detail by way of examples in combination with the accompanying drawings of the specification.

[0059] In the following description, many specific details are set forth in order to fully understand the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present application is not limited by the specific embodiments disclosed below.

[0060] In addition, in the description of the present application, it should be understood that the orientation or positional relationships indicated by the terms "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0061] In the present application, unless otherwise clearly defined and limited, the terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection, or a communication; it may be directly connected, or indirectly connected through an intermediate medium, and may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0062] In this application, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the description with reference to terms such as "embodiment", "example", "an embodiment", "example" or "specific example" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0063] Embodiment 1

[0064] A mechanical sand fishing device for treating solid-phase sediments in horizontal wells, as Figures 1-5 shown, includes a sand fishing mechanism 1 and a buffer anchoring mechanism 2;

[0065] The sand fishing mechanism 1 includes an upper joint 11, a sand pumping cylinder 12 and a sand fishing piston 13; the upper joint 11 is connected to one side of the sand pumping cylinder 12, the sand fishing piston 13 is connected to the other side of the sand pumping cylinder 12, and a sand storage cavity 5 is formed in the sand pumping cylinder 12; a sediment check valve 6 is connected between the upper joint 11 and the sand storage cavity 5, and a sand pumping check valve 7 is connected between the sand pumping piston and the sand storage cavity 5; the sand pumping piston has a sand fishing channel for connecting the casing and the inner cavity of the sand pumping piston, and a sand passing channel for connecting the inner cavity of the sand pumping piston and the sand storage cavity 5;

[0066] The buffer anchoring mechanism 2 includes an anchoring piston 21, an anchoring housing 22 and a guide head 23; the guide head 23 is connected to one side of the anchoring housing 22 for inserting into the sand and gravel; a plurality of anchoring slips 20 are slidably connected to the periphery of the anchoring housing 22; one side of the anchoring piston 21 is slidably connected inside the anchoring housing 22, and the other end is fixedly connected to the sand fishing piston 13; a return piston 8 is slidably connected inside the anchoring housing 22, and the return piston 8 is connected to a buffer mechanism 14, and the buffer mechanism 14 is configured to: when the sand fishing piston 13 pushes the return piston 8 to move so that the anchoring slips 20 protrude outwards to lock with the inner wall of the casing, the buffer mechanism 14 can absorb energy; when the sand fishing is completed, the buffer mechanism 14 can release the energy to push the return piston 8 to reset, so that the anchoring slips 20 are released from locking with the inner wall of the casing.

[0067] The sand fishing mechanism 1 of this application realizes the fishing of sand and gravel and liquid in the annulus part of the casing. Under the dual action of the high-pressure buffer air chamber 9 and the liquid storage cavity 10 of the buffer rivet mechanism of this application, when the pipe string quickly presses down the sand fishing device and hits the sediment, it can also play a certain buffering role on the sand fishing device and protect the pipe string.

[0068] When actually applied, the buffer anchoring mechanism 2 is used to be fixed in the rock, and the sand fishing mechanism 1 is connected to the buffer anchoring mechanism 2 to realize the sand fishing operation in the casing. By inserting the sand fishing device into the casing and then placing it in the horizontal section of the horizontal well, the front of the buffer anchoring mechanism 2 faces the rock, and the rear of the buffer anchoring mechanism 2 is connected to the sand fishing mechanism 1. The upper joint 11 of the sand fishing mechanism 1 is threadedly connected to the pipe string. The entire sand fishing device is moved down and up by lifting and pressing the pipe string. When encountering resistance during the downward movement, it indicates that it touches the rock. After multiple rapid up-and-down movements, the guide head 23 can be made to impact towards the rock, and the guide head 23 can be inserted into the rock. It can also stir the solid substances in the liquid, making them loose and evenly spread out, further enabling the entire sand fishing device to move to a deeper position, which is beneficial for subsequent sand fishing. After multiple rapid up-and-down movements, when the guide head 23 enters a certain depth, it is lifted and then quickly dropped to make the guide head 23 inserted into the rock, realizing the fixation of the buffer anchoring mechanism 2, so that the sand fishing mechanism 1 is fixed in the casing. In order to further enhance the stability of the sand fishing device in the casing, an anchor slip 20 that can slide radially relative to the anchor housing 22 is also provided on the outer periphery of the anchor housing 22 in the buffer anchoring mechanism 2. When the anchor slip 20 protrudes radially outward from the outer peripheral surface of the anchor housing 22, it can be abutted and connected to the inner wall of the casing, so that the buffer anchoring mechanism 2 is tightly connected to the casing, which is beneficial for the next step of realizing the sand fishing work on the annulus part of the casing through the sand fishing mechanism 1.

[0069] A sand fishing piston 13 is connected inside a sand pumping cylinder 12 of a sand fishing mechanism 1, and an anchoring piston 21 is connected inside an anchoring housing 22 of a buffer anchoring mechanism 2. One end of the sand fishing piston 13 extending out of the sand pumping cylinder 12 is fixedly connected to one end of the anchoring piston 21 extending out of the anchoring housing 22, so that the sand fishing mechanism 1 is connected to the buffer anchoring mechanism 2. An upper joint 11 of the sand fishing mechanism 1 is fixedly connected to the sand pumping cylinder 12, and a pipe string is threadedly connected to one side of the upper joint 11. Therefore, when the pipe string is lifted and pressed down, although the sand pumping cylinder 12 is slidably connected to the sand fishing piston 13, as described below, there is a step surface on the sand fishing piston 13 for limiting the sand pumping cylinder 12, forming a limit on the sand pumping cylinder 12 in the axial direction. Therefore, even if the pipe string presses down the sand pumping cylinder 12 through the upper joint 11, when the sand pumping cylinder 12 is moved downward along the sand fishing piston 13 to the step surface, at this time, the sand pumping cylinder 12 can be in a locked state with the sand fishing piston 13, and then the sand fishing piston 13 is pushed to move downward. Since the sand fishing piston 13 is fixedly connected to the anchoring piston 21, the anchoring piston 21 is further pushed to move downward. The anchoring piston 21 drives a return piston 8 to move downward through a buffer mechanism 14, and the return piston 8 pushes the anchoring slips 20 to protrude outward and lock with the inner wall of the casing, realizing the locking between the buffer anchoring mechanism 2 and the casing; similarly, when it is necessary to take out the sand fishing device from the casing after sand fishing, the buffer mechanism 14 can push the return piston 8 to reset by releasing energy, and the anchoring slips 20 are reset as the return piston 8 is reset, thereby realizing the unlocking between the casing and the buffer anchoring mechanism 2.

[0070] As a preferred embodiment, as Figure 1 shown, the upper joint 11 is of a hollow structure, and a sand settling check valve 6 is connected inside the upper joint 11. The inner cavity of the upper joint 11 is communicated with the sand pumping cylinder 12 through the opening of the sand settling check valve 6, and the inner cavity of the upper joint 11 is disconnected from the sand pumping cylinder 12 through the closing of the sand settling check valve 6; a water outlet hole 24 communicating with the inner cavity of the upper joint 11 is provided on the upper joint 11, and a filtering device 25 is connected between the upper joint 11 and the sand pumping cylinder 12.

[0071] As Figure 1 shown, one side of the sand fishing piston 13 outside the sand pumping cylinder 12, that is, the right side of the sand fishing piston 13 shown in the figure, also has a step surface abutting against the sand pumping cylinder 12 to limit the movement of the sand pumping cylinder 12 along the sand fishing piston 13, and the sand pumping cylinder 12 can push the sand fishing piston 13 to move after being pressed down to abut against the sand fishing piston 13; a plurality of rubber rings are connected between the sand fishing piston 13 and the sand pumping cylinder 12 to enhance the sealing performance between the sand fishing piston 13 and the sand pumping cylinder 12 and prevent liquid from leaking between the sand fishing piston 13 and the sand pumping cylinder 12.

[0072] Figure 1On the left side of the inner part of the sand fishing piston 13, a sand pumping check valve 7 is connected. By opening the sand pumping check valve 7, the inner cavity of the sand fishing piston 13 is communicated with the sand storage cavity 5, and by closing the sand pumping check valve 7, the connection between the inner cavity of the sand fishing piston 13 and the sand storage cavity 5 is disconnected; at one end of the sand fishing piston 13 extending outside the sand pumping cylinder 12, a sand fishing channel penetrating the radial direction of the sand fishing piston 13 is provided, and the sand fishing channel can be communicated with the casing, so that the sand and liquid in the casing can enter the inner cavity of the sand fishing piston 13 through the sand fishing channel.

[0073] The sand fishing operation of the sand fishing mechanism 1 starts when the buffer anchoring mechanism 2 completes the locking with the casing. The pipe string pulls the sand pumping cylinder 12 upward through the upper joint 11, so that the space of the sand storage cavity 5 inside the sand pumping cylinder 12 increases, creating a negative pressure inside the sand pumping cylinder 12. The settling sand check valve 6 connected inside the upper joint 11 is closed under the action of the negative pressure, while the sand pumping check valve 7 inside the sand fishing piston 13 is opened under the action of the negative pressure. The sand fishing channel 26 on the sand fishing piston 13 sucks in solid and liquid substances due to the negative pressure of the sand pumping cylinder 12. The sand and liquid enter the inner cavity of the sand fishing piston 13 through the sand fishing channel 26, and then enter the sand storage cavity 5 inside the sand pumping cylinder 12 through the sand pumping check valve 7 at one end of the sand fishing piston 13 and the sand passing channel 27 for storage; at this time, there are both liquid and solid in the sand storage cavity 5. Then, the upper joint 11 is pressed down by the pipe string, so as to drive the sand pumping cylinder 12 to move downward through the upper joint 11. At this time, the volume of the sand storage cavity 5 inside the sand pumping cylinder 12 shrinks. Under the action of the pressure in the sand storage cavity 5, the settling sand check valve 6 is opened and the sand pumping check valve 7 is closed. The sand in the sand storage cavity 5 stays in the sand storage cavity 5 under the blocking action of the filtering device 25 of the sand storage cavity 5, while the liquid passes through the filtering device 25 and flows back into the annulus through the filtering action of the filtering device 25, the settling sand check valve 6 and the water outlet hole 24 of the upper joint 11. By taking out the sand fishing device from the casing and taking out the sand in the sand storage cavity 5, a sand fishing operation is completed.

[0074] It should be noted that both the sand pumping check valve 7 and the settling sand check valve 6 have springs, which helps the sand pumping check valve 7 and the settling sand check valve 6 to reset.

[0075] As a preferred embodiment, the anchoring housing 22 includes an anchoring cylinder head 221, an anchoring cylinder body 222, and a body housing 223; the anchoring cylinder head 221 is connected to the side of the anchoring cylinder body 222 facing the sand pumping cylinder 12, and the body housing 223 is connected between the anchoring cylinder body 222 and the guide head 23. The anchoring cylinder head 221, the anchoring cylinder body 222, the body housing 223, and the guide head 23 are fixedly connected to form the housing structure of the buffer anchoring mechanism 2. The anchoring cylinder head 221 and the anchoring cylinder body 222 can be connected by bolts, welding, or other connection methods, preferably threaded connection, because threaded connection can prevent the dead-end cavity when the anchoring piston 21 moves to the right relative to the anchoring cylinder body 222, and the thread can also play a role in filtering solid substances to prevent the anchoring piston 21 from being blocked when moving to the left and being able to return to its original position.

[0076] Further, the anchoring cylinder body 222 has a first cavity 3 and a second cavity 4 separated from each other; an anchoring piston 21 and a return piston 8 are slidably connected in the first cavity 3, a high-pressure buffer air chamber 9 is formed between one side of the return piston 8 and the anchoring piston 21, and the anchoring piston 21 compresses the high-pressure buffer air chamber 9 to push the return piston 8 to move; a liquid storage chamber 10 is formed in the first cavity 3 on the other side of the return piston 8.

[0077] The purpose of separating the anchoring cylinder body 222 into two independent chambers is that the first cavity 3 can have a liquid storage chamber 10 for storing liquid, and the second cavity 4 can accommodate the elastic liquid storage member 141 of the buffer mechanism 14. In this way, separating the liquid storage chamber 10 from the buffer mechanism 14 can lock the energy of the liquid storage chamber 10 and the buffer mechanism 14 in their respective regions, and realize the absorption and release of the energy of the buffer mechanism 14 by means of connection or disconnection.

[0078] One side in the first cavity 3 is connected with an anchoring piston 21. One end of the piston rod of the anchoring piston 21 extends out of the anchoring cylinder body 222 and is fixedly connected with the sand fishing piston 13. The end of the anchoring piston 21 connected with the piston head is slidably connected in the anchoring cylinder body 222; the anchoring piston 21 and the anchoring cylinder head 221 are connected by a rubber ring to enhance the sealing performance between the anchoring piston 21 and the anchoring cylinder head 221; the anchoring piston 21 and the anchoring cylinder body 222 are connected by a rubber ring to enhance the sealing performance between the anchoring cylinder body 222 and the anchoring piston 21.

[0079] On the other side of the first cavity 3, there is a resurrection piston connected. The piston head side of the resurrection piston faces the anchoring piston 21, and the piston rod side of the resurrection piston faces the body housing 223. Since a high-pressure buffer air chamber 9 is formed in the anchoring liquid cylinder body 222 located between the anchoring piston 21 and the resurrection piston, when the anchoring piston 21 moves downward to compress the high-pressure buffer air chamber 9, the high-pressure gas in the high-pressure buffer air chamber 9 can be fully compressed and then transfer the pressure to the resurrection piston, thereby pushing the resurrection piston to move downward.

[0080] Specifically, for the high-pressure buffer air chamber 9 between the reset piston 8 and the anchoring piston 21, when assembled under normal pressure, it is sealed by rubber rings between the anchoring piston 21 and the anchoring liquid cylinder body 222, and sealed by rubber rings between the reset piston 8 and the anchoring liquid cylinder body 222, so that the high-pressure buffer air chamber 9 has gas higher than normal pressure. This gas is used to avoid the phenomenon of vacuum pumping between the reset piston 8 and the anchoring piston 21 when the anchoring piston 21 and the reset piston 8 generate relative displacement.

[0081] As a preferred embodiment, the buffer mechanism 14 includes an elastic liquid storage member 141, a first connecting pipe 142, and a second connecting pipe 143. The elastic liquid storage member 141 is arranged in the second cavity 4. The elastic liquid storage member 141 is connected to the liquid storage cavity 10 through the first connecting pipe 142 and the second connecting pipe 143. The liquid in the liquid storage cavity 10 flows to the elastic liquid storage member 141 through the first connecting pipe 142, and the liquid in the elastic liquid storage member 141 flows back to the liquid storage cavity 10 through the second connecting pipe 143.

[0082] The elastic liquid storage member 141 of the buffer mechanism 14 is located in the second cavity. The elastic liquid storage member 141 can adopt a water bag, an accumulator or other elastic energy storage devices, and the purpose is to be able to buffer the liquid. In order to realize the flow of the liquid in the liquid storage cavity 10 into the elastic liquid storage member 141, or the output of the liquid in the elastic liquid storage member 141 to the liquid storage cavity 10, a first channel and a second channel are opened between the first cavity 3 and the second cavity 4. The first connecting pipe 142 is connected in the first channel, and the second connecting pipe 143 is connected in the second channel. When the reset piston 8 moves downward, the reset piston 8 can compress the volume of the liquid storage cavity 10, so that the volume of the liquid storage cavity 10 decreases, and the liquid in the liquid storage cavity 10 flows to the elastic liquid storage member 141 through the first connecting pipe 142. When it is necessary to reset the reset piston 8, by controlling the liquid in the elastic liquid storage member 141 to flow back to the liquid storage cavity 10 through the second connecting pipe 143, the volume of the liquid storage cavity 10 continuously increases, thereby realizing the downward movement of the reset piston 8. Through the buffer mechanism 14, the energy when the reset piston 8 moves downward can be absorbed, so that the reset piston 8 can move downward to push the anchoring jaw 20 to bulge outwards. Through the buffer mechanism 14, the energy of the liquid can also be released and filled into the liquid storage cavity 10, thereby pushing the reset piston 8 to reset, so that the anchoring jaw 20 no longer bulges out of the outer peripheral surface of the body housing 223 for reset.

[0083] Further, a one-way throttle valve group 15 is connected to the first connecting pipe 142 to prevent liquid from flowing back into the liquid storage cavity 10 from the elastic liquid storage member 141; a timing valve group 16 is connected to the second connecting pipe 143 to control the duration of the liquid flowing back into the liquid storage cavity 10 from the elastic liquid storage member 141.

[0084] When the initial liquid storage cavity 10 is compressed with pressure, the liquid enters the elastic liquid storage member 141 through the one-way throttle valve group on the first connecting pipe 142. The starting pressure of the one-way throttle valve group 15 is small and can be used for buffering. Then, as the pressure increases, after a large amount of liquid enters the elastic liquid storage member 141 through the liquid storage cavity 10 and the first connecting pipe 142, the reset piston 8 will move downward accordingly, and the position shown in the figure will move to the right. When it moves to the point where the pressure in the initial liquid storage cavity 10 is the same as the pressure in the elastic liquid storage cavity 10, it will no longer move. At this time, the reset piston 8 will not be subjected to external mechanical forces.

[0085] When it is necessary to reset the reset piston 8, that is, when moving in the left direction shown in the figure, the timing valve group 16 on the second connecting pipe 143 is opened. The timing valve group 16 adopts a controllable throttle valve. By controlling the throttle, the pressure relief speed of the liquid flowing from the elastic liquid storage member 141 into the liquid storage cavity 10 is controlled, thereby controlling the flow rate to achieve the purpose of slow pressure relief, and the length of time can be controlled. Preferably, the time for the liquid to flow back from the elastic liquid storage member 141 to the liquid storage cavity 10 is controlled to be 10 minutes.

[0086] Further, the buffer mechanism 14 further includes a reset spring 144 disposed in the first cavity 3; one end of the reset spring 144 is abutted and connected to the reset piston 8, and the other end of the reset spring 144 is abutted and connected to the inner wall of the liquid storage cavity 10.

[0087] To further enhance the running stability of the reset piston 8, a reset spring 144 is connected to the right side of the reset piston 8 as shown in the figure. The reset spring 144 is located in the liquid storage cavity 10, abuts and connects to the reset piston 8 on one side and abuts and connects to the wall surface of the liquid storage cavity 10 on the other side. When the reset piston 8 moves to the right, it can compress the reset piston 8, and the reset piston 8 can store energy. When the reset piston 8 moves to the left, the reset piston 8 can release energy in both the elastic liquid storage member 141 and the reset spring 144, and the reset piston 8 moves to the left under the dual action to achieve reset. In addition, when the anchoring piston 21 moves to the right and drives the reset piston 8 to move to the right, the reset spring 144 can offset the piston force generated by the high-pressure gas in the high-pressure buffer chamber 9 on the reset piston 8, making the reset piston 8 run smoothly.

[0088] As a preferred embodiment, a support rod 17 is slidably connected inside the body housing 223. The piston rod of the return piston 8 sequentially passes through the liquid storage chamber 10, the second cavity 4 to the inside of the body housing 223 and is connected to the support rod 17.

[0089] As Figure 1 As shown, a support rod 17 fixedly connected to the return piston 8 is slidably connected inside the body housing 223. One side of the piston head of the return piston 8 is slidably connected inside the anchoring cylinder block 222. One side of the piston rod of the return piston 8 can pass through the liquid storage chamber 10, the anchoring cylinder block 222, the second chamber, and the body housing 223 and enter the inside of the body housing 223 to be fixedly connected to the support rod 17. Rubber rings are provided between the return piston 8 and the anchoring cylinder block 222, and between the return piston 8 and the body housing 223 to enhance the sealing performance between the return piston 8 and the anchoring cylinder block 222, and between the return piston 8 and the body housing 223, and prevent the liquid in the liquid storage chamber 10 from leaking through the gap between the return piston 8 and the anchoring cylinder block 222 or between the return piston 8 and the body housing 223.

[0090] When the return piston 8 moves to the right, the liquid in the liquid storage chamber 10 enters the elastic liquid storage member 141 through the first connecting pipe 142 and the one-way throttle valve group 15, and the return piston 8 drives the support rod 17 to move to the right;

[0091] Further, the support rod 17 adopts a variable diameter structure. The small diameter end 18 of the support rod 17 faces the guide head 23 side, and the large diameter end 19 of the support rod 17 is fixedly connected to the return piston 8. Therefore, when the support rod 17 moves to the right, the small diameter end 18 and the large diameter end 19 of the support rod 17 inside the body housing 223 move to the right in sequence.

[0092] The anchoring slips 20 are arranged at intervals along the circumference of the body housing 223 in the groove of the body housing 223, and the anchoring slips 20 can slide in the radial direction of the body housing 223. A plurality of sliding bearings are connected between the inner side of the anchoring slips 20 and the support rod 17. The initial position of the anchoring slips 20 is in the groove and corresponds to the small diameter end 18 of the support rod 17. When the support rod 17 moves to the right, the contact between the support rod 17 and the anchoring slips 20 gradually changes from the small diameter end 18 to the large diameter end 19 of the support rod 17, so that the anchoring slips 20 move from the groove of the body housing 223 to the outside of the body housing 223 in the radial direction and protrude from the circumferential surface of the body housing 223. At this time, the anchoring slips 20 are abutted and connected between the inner wall of the casing and the outer circumferential surface of the body housing 223, so that the buffer anchoring mechanism 2 is locked and connected to the casing, thereby realizing the stable connection of the sand fishing device in the casing and facilitating the next sand fishing operation.

[0093] Embodiment 2

[0094] The present application also relates to a method for fishing sand of solid-phase sediments in a horizontal well, based on the mechanical sand fishing device for treating solid-phase sediments in a horizontal well described above. The specific steps include:

[0095] S1: Connect the upper joint 11 to the end of the pipe string, and lower the sand fishing device into the casing so that the sand fishing device extends into the horizontal section of the horizontal well.

[0096] S2: When the guide head 23 touches the solid-phase substance, lift the sand fishing device and then quickly drop it to insert the guide head 23 into the settled sand.

[0097] Specifically, when the guide head 23 touches the solid-phase substance, lift the pipe string to drive the sand fishing device to move upward. Stir the solid-phase substances in the liquid through multiple up-and-down movements to make them loose and evenly spread out, so that the sand fishing device extends to a deeper position. When the guide head 23 encounters resistance at the moving position, the sand fishing device can stop moving downward at this time. At the wellhead, quickly drop the pipe string after lifting it, so that the guide head 23 is inserted into the sand and gravel.

[0098] S3: Press down the pipe string to apply pressure to the sand pumping cylinder 12 through the upper joint 11. The sand pumping cylinder 12 pushes the sand fishing piston 13 to move towards the guide head 23 side, and then pushes the reset piston 8 and the support rod 17 to move, so that the support rod 17 pushes the anchor slip 20 to protrude outward and abut against the inner wall of the casing, locking the buffer mechanism 14 to the casing.

[0099] Specifically, step S3 specifically includes:

[0100] The sand fishing piston 13 moves towards the guide head 23 side, and the sand fishing piston 13 compresses the gas in the high-pressure buffer gas chamber 9 to drive the reset piston 8 to move towards the guide head 23 side;

[0101] The liquid in the compression liquid storage cavity 10 enters the elastic liquid storage member 141 for energy storage. After pressing down for a period of time, when the pressure in the liquid storage cavity 10 is balanced with the pressure in the elastic liquid storage member 141, the liquid stops flowing;

[0102] The reset piston 8 pushes the support rod 17 to move, so that the anchor slip 20 gradually abuts against the large-diameter end 19 side from abutting against the small-diameter end 18 side of the support rod 17, so that the anchor slip 20 protrudes radially outward along the body housing 223 to the locking position abutting against the inner wall of the casing.

[0103] S4: Lift the pipe string upward, and a negative pressure is formed in the sand storage cavity 5 of the sand pumping cylinder 12, so that the sand pumping check valve 7 opens and the settled sand check valve 6 closes. The liquid and solid substances in the annulus between the casing and the sand fishing device enter the sand storage cavity 5 through the sand fishing channel and the inner cavity of the sand fishing piston 13.

[0104] Specifically, lift the pipe string upward so that the upper joint 11 drives the sand pumping cylinder 12 to move upward. The volume of the sand storage cavity 5 of the sand pumping cylinder 12 increases, and a negative pressure is formed in the sand storage cavity 5, causing Figure 1 the left sand settling check valve 6 in the upper joint 11 in the orientation shown in Figure 1 to close, and the sand pumping check valve 7 in the sand fishing piston 13 to open. The liquid and sand in the casing enter the inner cavity of the sand fishing piston 13 through the sand fishing channel and then enter the sand storage cavity 5 through the sand pumping check valve 7.

[0105] S5: Press the pipe string downward. The sand storage cavity 5 in the sand pumping cylinder 12 is compressed, causing the sand pumping check valve 7 to close and the sand settling check valve 6 to open. The liquid in the sand storage cavity 5 is discharged through the water outlet hole 24 of the upper joint 11. Take out the sand fishing device to clean the sand in the sand storage cavity 5 and then repeat the sand fishing process.

[0106] Specifically, the step S5 specifically includes:

[0107] Press the pipe string downward. The sand storage cavity 5 in the sand pumping cylinder 12 is compressed, causing the sand pumping check valve 7 to close and the sand settling check valve 6 to open. The solids in the sand storage cavity 5 are retained in the sand storage cavity 5 due to the filtering device 25 provided between the upper joint 11 and the sand storage cavity 5, and the liquid is discharged through the water outlet hole 24 of the upper joint 11 to the annulus;

[0108] By opening the timing valve group 16, the liquid in the elastic liquid storage member 141 flows back into the liquid storage cavity 10, and under the pushing action of the return spring 144 and the liquid in the liquid storage cavity 10, the return piston 8 is reset;

[0109] The return piston 8 drives the support member to move away from the side of the guide head 23, causing the anchor slip 20 to gradually abut against the small diameter end 18 side of the support rod 17 from the side abutting against the large diameter end 19 side of the support rod 17. Thus, the anchor slip 20 moves inward in the radial direction of the body housing 223 to the initial position, realizing the unlocking between the sand fishing device and the casing;

[0110] Lift the pipe string to take out the sand fishing device from the casing and clean the sand in the sand storage cavity 5;

[0111] Repeat the sand fishing process until the cleaning is completed.

[0112] What is not described in this application can be realized by adopting or referring to the existing technology.

[0113] Each embodiment in this specification is described in a progressive manner. The same or similar parts between each embodiment can be referred to each other, and the key points of each embodiment are the differences from other embodiments.

[0114] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. A mechanical sand fishing device for treating solid-phase sediments in horizontal wells, characterized in that, It includes a sand fishing mechanism and a buffer anchoring mechanism; The sand fishing mechanism includes an upper joint, a sand pumping cylinder, and a sand fishing piston; the upper joint is connected to one side of the sand pumping cylinder, the sand fishing piston is connected to the other side of the sand pumping cylinder, and a sand storage cavity is formed inside the sand pumping cylinder; a sedimentation check valve is connected between the upper joint and the sand storage cavity, and a sand pumping check valve is connected between the sand pumping piston and the sand storage cavity; the sand pumping piston has a sand fishing channel that connects the casing to the inner cavity of the sand pumping piston, and a sand passing channel that connects the inner cavity of the sand pumping piston to the sand storage cavity; The buffer anchoring mechanism includes an anchoring piston, an anchoring housing, and a guide head; the guide head is connected to one side of the anchoring housing for inserting into the sand and gravel; a plurality of anchoring slips are slidably connected to the periphery of the anchoring housing; one side of the anchoring piston is slidably connected inside the anchoring housing, and the other end is fixedly connected to the sand fishing piston; a return piston is slidably connected inside the anchoring housing, and the return piston is connected to a buffer mechanism, and the buffer mechanism is configured to: when the sand fishing piston pushes the return piston to move so that the anchoring slips protrude outwards and lock with the inner wall of the casing, the buffer mechanism can absorb energy; when the sand fishing is completed, the buffer mechanism can release energy to push the return piston to reset, so that the anchoring slips are disengaged from the inner wall of the casing.

2. The mechanical sand fishing device for treating solid-phase sediments in horizontal wells according to claim 1, wherein There are a first cavity and a second cavity separated from each other inside the anchoring housing; An anchoring piston and a return piston are slidably connected inside the first cavity. A high-pressure buffer air chamber is formed between one side of the return piston and the anchoring piston. The anchoring piston compresses the high-pressure buffer air chamber to push the return piston to move; a liquid storage cavity is formed inside the first cavity on the other side of the return piston; The buffer mechanism includes an elastic liquid storage member, a first connecting pipe, and a second connecting pipe. The elastic liquid storage member is arranged inside the second cavity. The elastic liquid storage member is connected to the liquid storage cavity through the first connecting pipe and the second connecting pipe. The liquid in the liquid storage cavity flows to the elastic liquid storage member through the first connecting pipe, and the liquid in the elastic liquid storage member flows back to the liquid storage cavity through the second connecting pipe.

3. The mechanical sand fishing device for treating solid-phase sediments in a horizontal well according to claim 2, characterized in that A one-way throttle valve group is connected to the first connecting pipe to prevent the liquid from flowing back into the liquid storage cavity from the elastic liquid storage member; a timing valve group is connected to the second connecting pipe to control the duration of the liquid flowing back into the liquid storage cavity from the elastic liquid storage member.

4. A mechanical sand fishing device for treating solid-phase sediments in a horizontal well according to claim 2, characterized in that, The buffer mechanism further includes a return spring arranged inside the first cavity; one end of the return spring abuts and connects to the return piston, and the other end of the return spring abuts and connects to the inner wall of the liquid storage cavity.

5. The mechanical sand fishing device for treating solid-phase sediments in horizontal wells according to claim 1, wherein, The anchoring housing includes an anchoring cylinder cap, an anchoring cylinder body, and a body outer shell; the anchoring cylinder cap is connected to the side of the anchoring cylinder body facing the sand pumping cylinder, and the body outer shell is connected between the anchoring cylinder body and the guide head; a support rod is slidably connected inside the body outer shell, and the piston rod of the return piston sequentially passes through the liquid storage cavity, the second cavity to the inside of the body outer shell and is connected to the support rod.

6. The mechanical sand fishing device for treating solid-phase sediments in horizontal wells according to claim 5, wherein, The support rod adopts a variable diameter structure. The small diameter end of the support rod faces the side of the guide head, and the large diameter end of the support rod is fixedly connected to the return piston; A plurality of anchoring slips are slidably connected to the periphery of the body outer shell. A plurality of sliding bearings are connected between the anchoring slips and the support rod, so that the anchoring slips are configured to: It has an initial position in contact connection with the outer periphery of the small-diameter end of the support rod, and when the reset piston moves to drive the support rod to move towards the guide head side, the large-diameter end of the support rod contacts the anchoring slip, causing the anchoring slip to protrude radially outward and abut against the inner wall of the casing at the locking position.

7. The mechanical sand fishing device for treating solid-phase sediments in horizontal wells according to claim 1, wherein, The upper joint is provided with a water outlet hole communicating with the inner cavity of the upper joint, and a filtering device is connected between the upper joint and the sand pumping cylinder; On the side of the sand fishing piston outside the sand pumping cylinder, there is also a step surface abutting against the sand pumping cylinder to limit the movement of the sand pumping cylinder along the sand fishing piston, and after the sand pumping cylinder is pressed down to abut against the sand fishing piston, it can push the sand fishing piston to move; When the sand pumping cylinder is lifted, a negative pressure is formed in the sand storage cavity, causing the sediment check valve to close and the sand pumping check valve to open. The liquid and sand pass through the sand fishing channel, through the inner cavity of the sand fishing piston, and through the sand passing channel into the sand storage cavity; when the sand pumping cylinder is pressed down, the sand storage cavity is compressed, the sand pumping check valve closes, the sediment check valve opens, and the sand in the sand storage cavity is stored in the sand storage cavity under the blocking action of the filtering device, and the liquid flows out through the water outlet hole.

8. A method for sand fishing of solid phase sediments in horizontal wells, based on a mechanical sand fishing device for treating solid phase sediments in horizontal wells according to any one of claims 1-7, characterized in that, The specific steps include: S1: Connect the upper joint to the end of the pipe string and lower the sand fishing device into the casing so that the sand fishing device extends into the horizontal section of the horizontal well; S2: When the guide head touches the solid phase material, lift the sand fishing device and then quickly hammer it down so that the guide head inserts into the sediment; S3: Press down the pipe string, apply pressure to the sand pumping cylinder through the upper joint, the sand pumping cylinder pushes the sand fishing piston to move towards the guide head side, and then drives the reset piston and the support rod to move, so that the support rod pushes the anchoring slip to protrude outward and abut against the inner wall of the casing, locking the buffer mechanism with the casing; S4: Lift the pipe string upward, a negative pressure is formed in the sand storage cavity in the sand pumping cylinder, causing the sand pumping check valve to open and the sediment check valve to close, and the liquid and solid substances in the annulus between the casing and the sand fishing device pass through the sand fishing channel and through the inner cavity of the sand fishing piston into the sand storage cavity; S5: Press down the pipe string, the sand storage cavity in the sand pumping cylinder is compressed, causing the sand pumping check valve to close and the sediment check valve to open, and the liquid in the sand storage cavity is discharged through the water outlet hole of the upper joint; take out the sand fishing device to clean the sand in the sand storage cavity and then repeat the sand fishing process.

9. A method for fishing sand of solid-phase sediment in a horizontal well according to claim 8, characterized in that, The specific step S3 includes: The sand fishing piston moves towards the guide head side, and the sand fishing piston compresses the gas in the high-pressure buffer air chamber to drive the reset piston to move towards the guide head side; Compress the liquid in the liquid storage cavity into the elastic liquid storage member for energy storage. After pressing down for a period of time, when the pressure in the liquid storage cavity is balanced with the pressure in the elastic liquid storage member, the liquid stops flowing; The reset piston pushes the support rod to move, causing the anchoring slip to gradually abut against the large-diameter end side from abutting against the small-diameter end side of the support rod, so that the anchoring slip protrudes radially outward along the body shell to the locking position abutting against the inner wall of the casing.

10. A method for fishing sand of solid-phase sediment in a horizontal well as described in claim 8, characterized in that, The specific step S5 includes: Press down the pipe string, the sand storage cavity in the sand pumping cylinder is compressed, causing the sand pumping check valve to close and the sediment check valve to open. The solids in the sand storage cavity are retained in the sand storage cavity due to the filtering device provided between the upper joint and the sand storage cavity, and the liquid is discharged through the water outlet hole of the upper joint to the annulus; By opening the timing valve group, the liquid in the elastic liquid storage member flows back into the liquid storage cavity, and under the pushing action of the return spring and the liquid in the liquid storage cavity, the return piston is reset; The return piston drives the support member to move away from the side of the guiding head, so that the anchoring slip gradually abuts against the small-diameter end side of the support rod from abutting against the large-diameter end side of the support rod, thereby causing the anchoring slip to move radially inward along the body housing to the initial position, realizing the unlocking between the sand fishing device and the casing; The pipe string is lifted to take out the sand fishing device from the casing, and the sand and gravel in the sand storage cavity are cleaned; The sand fishing process is repeated until the cleaning is completed.

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