Toe end sliding sleeve and sliding sleeve opening control method

Abstract

The present application provides a toe-end sliding sleeve and a sliding sleeve opening control method, which relates to the field of oil and gas production technology. The toe-end sliding sleeve includes: an upper joint, a connector, and a lower joint connected in sequence to form a hollow pipe structure; the side wall of the upper joint is provided with a liquid outlet, the inner wall of the connector is provided with a connecting port, and the side wall of the connector is provided with a pressure-conducting channel connecting the lower end of the connector and the connecting port; the side wall of the lower joint is provided with a valve channel, one end of the valve channel is connected to the pressure-conducting channel and the other end extends to the inner wall of the lower joint to form a port, a control valve is provided in the valve channel, and a soluble plug is provided at the port, a battery and an electronic control module are provided in the side wall of the lower joint, and a pressure sensor connected to the electronic control module is provided on the inner wall of the lower joint; the sliding sleeve, the upper end of which is sleeved inside the upper joint to block the liquid outlet, and the lower end is sleeved inside the connector to block the connecting port. The toe-end sliding sleeve solves the problem that the current toe-end sliding sleeve cannot be opened normally or the opening technology is opened by erroneous operation.

Description

Technical Field

[0001] The present application relates to the field of oil and gas production technology, and in particular to a toe sleeve and a sleeve opening control method. Background Art

[0002] The toe end sliding sleeve is a pipe that is lowered into the well along with the cementing string. After the cementing operation is completed, the toe end sliding sleeve is opened through a special triggering method to carry out subsequent fracturing operations. This tool can quickly establish a fracturing channel between the wellbore and the oil layer, with high sliding sleeve opening efficiency and large pressure channel displacement.

[0003] However, the existing toe-end sliding sleeve can be mainly divided into four types: rupture disc type, delay type, electric control type and soluble type. The specific problems are as follows: the rupture disc type toe-end sliding sleeve has a built-in bursting disc, which relies on holding pressure to open, which conflicts with the casing pressure test. There is a problem that the success rate of holding pressure to open the toe-end sliding sleeve is low after the casing pressure test process is completed; the delay type toe-end sliding sleeve has a built-in delay valve, which can delay the opening of the toe-end sliding sleeve after the casing pressure test process is completed, but if the casing pressure test process cannot be completed smoothly as scheduled, the delay time is exceeded, and the sliding sleeve has the problem of being opened by mistake; the soluble toe-end sliding sleeve has a built-in soluble plug, and the sliding sleeve opens after the soluble plug dissolves. The problem is the same as that of the delay type. Once the casing pressure test process cannot be completed smoothly as scheduled, the dissolution time of the soluble plug is exceeded, and the sliding sleeve has the problem of being opened by mistake; the electric control type soluble sliding sleeve has a built-in electric control piston or solenoid valve controlled sliding sleeve to open, but in deep wells and ultra-deep wells, due to the high bottom hole pressure, the electric control switch or solenoid valve has the problem of being unable to normally control the opening of the sliding sleeve.

[0004] Therefore, the above technical problems need to be further solved. Summary of the invention

[0005] The main purpose of the present invention is to provide a toe end sliding sleeve and a sliding sleeve opening control method to solve the above-mentioned technical problem that the toe end sliding sleeve cannot be opened normally or is opened by erroneous operation.

[0006] In order to solve the above technical problems, the embodiments of the present application provide the following technical solutions:

[0007] On the one hand, the present application provides a toe end sliding sleeve, comprising: an upper joint, a connecting head, and a lower joint connected in sequence to form a hollow pipe structure;

[0008] Wherein, the side wall of the upper joint is provided with a liquid outlet, the inner wall of the connector is provided with a connecting port, and the side wall of the connector is provided with a pressure-conducting channel connecting the lower end of the connector and the connecting port; the side wall of the lower joint is provided with a valve channel, one end of the valve channel extends to a position connected with the pressure-conducting channel, and the other end of the valve channel extends to the inner wall of the lower joint to form a port, a control valve is provided in the valve channel, and a soluble plug is provided at the port, a battery and an electronic control module are provided in the side wall of the lower joint, the battery, the electronic control module and the control valve are electrically connected, a pressure sensor is provided on the inner wall of the lower joint, and the pressure sensor is connected to the electronic control module;

[0009] A sliding sleeve, the upper end of which is sleeved inside the upper joint to seal the liquid outlet, and the lower end of which is sleeved inside the connector to seal the connector;

[0010] Among them, after the soluble plug is dissolved, when the pressure sensor receives a preset pressure wave code and transmits a pressure signal to the electronic control module, the electronic control module can control the control valve to open based on the pressure signal, and the connecting port is connected to the port.

[0011] The purpose of the present invention can be further achieved by adopting the following technical measures.

[0012] Optionally, the aforementioned toe end sliding sleeve further comprises:

[0013] The outer sleeve is connected to the connector and is sleeved on the outer side of the lower connector. The outer sleeve and the lower connector form a sealed accommodating cavity in which the battery and the electric control module are arranged.

[0014] Optionally, the aforementioned toe end sliding sleeve, wherein the sliding sleeve is connected to the upper joint by penetrating a shear pin.

[0015] Optionally, in the aforementioned toe end sliding sleeve, the connector forms a first step hole, a second step hole and a third step hole with decreasing apertures from the upper end to the lower end, and forms a first step and a second step, and the connecting port is located at the first step;

[0016] A limiting ring is provided on the outer wall of the sleeve, and the limiting ring is sleeved in the first step hole. When the connecting port is connected with the port, well fluid flows out through the connecting port to pressurize the limiting ring to make the sleeve slide, and the second step limits the limiting ring.

[0017] Optionally, in the aforementioned toe-end sliding sleeve, the upper end of the upper joint is a female head and the lower end is a male head, the inner wall of the first step hole of the connecting head is provided with threads to form a female head, the upper joint and the connecting head are threadedly connected, and the lower end of the upper joint is a preset distance from the first step.

[0018] Optionally, in the aforementioned toe end sliding sleeve, the inner and outer walls of the lower end of the connector are both provided with threads, and the upper end of the lower connector is a male connector and is connected to the internal threads of the lower end of the connector;

[0019] The top end of the outer sleeve is a female head and is connected to the external thread at the lower end of the connector.

[0020] Optionally, in the aforementioned toe-end sliding sleeve, the number of flow channels formed by the connecting port and the pressure-conducting channel is multiple, and the multiple flow channels are evenly spaced around the side wall of the connecting head.

[0021] Optionally, in the aforementioned toe end sliding sleeve, the number of the valve channels is multiple and evenly spaced in the side wall of the lower joint, each valve channel is provided with a control valve, the port of each valve channel is blocked with the soluble plug, and the multiple valve channels are respectively connected to multiple flow channels;

[0022] Wherein, all the control valves are connected to the electronic control module.

[0023] Optionally, in the aforementioned toe end sliding sleeve, the soluble plug is made of a material that can be dissolved in acid;

[0024] Alternatively, the soluble plug is made of a material that can be dissolved in alkali solution.

[0025] On the other hand, the present application provides a sleeve opening control method for the above-mentioned toe sleeve, comprising:

[0026] Using a preset liquid to dissolve the soluble plug, or waiting for the soluble plug to dissolve itself after a preset time in the well;

[0027] Applying a preset pressure wave code pressure into the well, and transmitting a preset pressure wave code signal through the well fluid;

[0028] The preset pressure wave code is collected and compared. When the preset pressure wave code is consistent with the pre-stored pressure wave code, the control valve of the toe end sleeve is opened to connect the connecting port of the toe end sleeve with the port, so that the well fluid enters and pushes the sleeve downward, and the liquid outlet of the toe end sleeve is opened.

[0029] By means of the above technical solution, the toe end sliding sleeve and the sliding sleeve opening control method of the present invention have at least the following advantages:

[0030] The toe end sliding sleeve of the embodiment of the present invention has a pressure conducting channel arranged in its connector, and a connecting port arranged on the inner wall, a valve channel arranged in the lower connector, and a port arranged on the inner wall, the valve channel is communicated with the pressure conducting channel, the port is blocked by a soluble plug, and a normally closed control valve is arranged in the valve channel. When in use, when the toe end sliding sleeve of the present application is placed in a well for a period of time, the soluble plug can be dissolved, or an acidic or alkaline liquid is introduced into the well to dissolve the soluble plug, and then the pressure of a preset pressure wave code can be applied to the well as a signal to open the sliding sleeve, and when the pressure sensor detects the preset pressure wave code, the pressure signal will be transmitted to the electronic control module, and the electronic control module will control the control valve to open, thereby connecting the port with the connecting port, and at this time, the well fluid in the middle channel of the toe end sliding sleeve can enter from the port and flow out from the connecting port, and the sliding sleeve can be pushed downward by the action of the liquid, thereby opening the liquid outlet of the sliding sleeve block, and completing the opening action of the toe end sliding sleeve. It can be seen that the toe end sliding sleeve of the present application controls the opening of the sliding sleeve through the pressure wave code signal, which can effectively avoid the occurrence of misoperation opening and failure to open normally.

[0031] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] By reading the detailed description below with reference to the accompanying drawings, the above and other purposes, features and advantages of the exemplary embodiments of the present application will become easy to understand. In the accompanying drawings, several embodiments of the present application are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0033] Figure 1 A schematic diagram of the cross-sectional structure of a toe end sliding sleeve is shown schematically;

[0034] Figure 2 A schematic diagram of the cross-sectional structure of a connecting head of a toe end sliding sleeve is shown schematically.

[0035] The reference numerals in the accompanying drawings are:

[0036] Upper joint 1, liquid outlet 11, connector 2, connecting port 21, pressure guiding channel 22, first step hole 23, second step hole 24, third step hole 25, first step 26, second step 27, lower joint 3, valve channel 31, port 32, control valve 4, soluble plug 5, battery 6, electronic control module 7, pressure sensor 8, sleeve 9, limit ring 91, outer sleeve 10, accommodating chamber 101. DETAILED DESCRIPTION

[0037] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0038] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should have the common meanings understood by technicians in the field to which this application belongs.

[0039] Embodiment 1

[0040] like Figure 1 and Figure 2 As shown, a toe end sliding sleeve proposed in the first embodiment of the present invention comprises: an upper joint 1, a connector 2, and a lower joint 3 which are connected in sequence to form a hollow pipe structure;

[0041] Wherein, the side wall of the upper joint 1 is provided with a liquid outlet 11, the inner wall of the connector 2 is provided with a connecting port 21, and the side wall of the connector 2 is provided with a pressure-conducting channel 22 connecting the lower end of the connector 2 and the connecting port 21; the side wall of the lower joint 3 is provided with a valve channel 31, one end of the valve channel 31 extends to a position connected with the pressure-conducting channel 22, and the other end of the valve channel 31 extends to the inner wall of the lower joint 3 and forms a port 32, a control valve 4 is provided in the valve channel 31, and a soluble plug 5 is provided at the port 32; a battery 6 and an electronic control module 7 are provided in the side wall of the lower joint 3, and the battery 6, the electronic control module 7 and the control valve 4 are electrically connected; a pressure sensor 8 is provided on the inner wall of the lower joint 3, and the pressure sensor 8 is connected to the electronic control module 7;

[0042] A sliding sleeve 9, the upper end of which is sleeved inside the upper joint 1 to block the liquid outlet 11, and the lower end of which is sleeved inside the connector 2 to block the connection port 21;

[0043] Among them, after the soluble plug 5 is dissolved, when the pressure sensor 8 receives the preset pressure wave code and transmits the pressure signal to the electronic control module 7, the electronic control module 7 can control the control valve 4 to open based on the pressure signal, and the connecting port 21 is connected to the port 32.

[0044] Specifically, in order to facilitate the description of the structure of the toe end sleeve provided in the embodiment of the present application, all the upper and lower parts in the present application correspond to the upper and lower parts of the toe end sleeve in actual use, and because the toe end sleeve has a fixed upper and lower direction when in use, the expressions containing the concepts of upper and lower in the present application are accurate and unambiguous. Among them, the connection between the upper joint 1, the connector 2, and the lower joint 3 is a sealed connection, for example, it can be a fine thread connection, or it can be a sealed connection by setting a sealed matching structure.

[0045] The structure of the upper joint 1 is the same as that of the upper joint 1 of the toe end sleeve in the prior art, which is used to connect the casing. The liquid outlet 11 on its side wall can be a circular through hole, and the number can be one or more, and preferably multiple, and are evenly spaced and distributed on the side wall of the upper joint 1. The liquid outlet 11 is used to connect with the internal channel of the toe end sleeve after the toe end sleeve is opened, so that the liquid outlet 11 is connected with the internal channel of the toe end sleeve for liquid injection to implement fracturing work.

[0046] The connector 2 is a transfer tube body for connecting the upper connector 1 and the lower connector 3. The pressure-conducting channel 22 provided on the side wall of the connector 2 can be a channel that passes through the upper and lower ends of the connector 2, or a connection port 21 that connects the lower end of the connector 2 and the inner wall.

[0047] The connection between the sliding sleeve 9 and the upper joint 1 and the connecting head 2 can be relatively sealed, and fixed to the upper joint 1 by shear pins.

[0048] The valve channel 31 provided on the lower connector 3 needs to be connected to the upper end of the lower connector 3 at one end, and the setting position of the valve channel 31 needs to ensure that the valve channel 31 is connected to the pressure-conducting channel 22 after the lower connector 3 is connected to the connector 2, and the other end of the valve channel 31 needs to be connected to the interior of the lower connector 3, thereby forming a port 32 on the inner wall of the lower connector 3. The connection between the control valve 4 and the valve channel 31 needs to be sealed, for example, using a fine thread connection, and sealing with other sealing media or gaskets. The shape of the soluble plug 5 sealed in the port 32 needs to be adapted to the port 32, and the two can be threaded or interference fit, and the end of the soluble plug 5 is preferably flush with the inner wall of the lower connector 3. The battery 6 and the electronic control module 7 can be set in a groove reserved on the side wall of the lower connector 3, and after the battery 6 and the electronic control module 7 are placed, the groove is sealed by a seal, or other components can be used to form a sealed cavity with the lower connector 3 to accommodate the battery 6 and the electronic control module 7. However, it should be noted that a channel needs to be reserved in the lower connector 3 for the wires connecting the control valve 4 and the battery 6 and the control valve 4 and the electronic control module 7 to pass through.

[0049] The toe-end sliding sleeve of the embodiment of the present invention has a pressure-conducting channel 22 arranged in its connector 2, and a connecting port 21 arranged on the inner wall, a valve channel 31 arranged in the lower connector 3, and a port 32 arranged on the inner wall, the valve channel 31 is communicated with the pressure-conducting channel 22, the port 32 is blocked by a soluble plug 5, and a normally closed control valve 4 is arranged in the valve channel 31. When in use, when the toe end sleeve of the present application is placed in the well for a period of time, the soluble plug 5 can be dissolved, or an acidic or alkaline liquid can be introduced into the well to dissolve the soluble plug 5. After that, the pressure of the preset pressure wave code can be applied to the well as a signal to open the sleeve 9. When the pressure sensor 8 detects the preset pressure wave code, it will transmit the pressure signal to the electronic control module 7, and the electronic control module 7 will control the control valve 4 to open, so that the port 32 is connected with the connecting port 21. At this time, the well fluid in the middle channel of the toe end sleeve can enter from the port 32 and flow out from the connecting port 21. Under the action of the liquid, the sleeve 9 can be pushed downward. For example, a protrusion or a groove can be set on the side wall of the sleeve 9, so that the well fluid pushes the protrusion or the groove to push the sleeve 9, and then the liquid outlet 11 blocked by the sleeve 9 is opened to complete the opening action of the toe end sleeve. It can be seen that the toe end sleeve of the present application controls the opening of the sleeve 9 through the pressure wave code signal, which can effectively avoid the occurrence of misoperation and failure to open normally.

[0050] like Figure 1 As shown, in a specific implementation, the toe-end sliding sleeve of the embodiment of the present application further includes: a sleeve 10, which is connected to the connecting head 2 and is sleeved on the outside of the lower joint 3, and the sleeve 10 and the lower joint 3 form a sealed accommodating cavity 101, and the battery 6 and the electronic control module 7 are arranged in the accommodating cavity 101.

[0051] Specifically, one end of the outer sleeve 10 is connected to the lower end of the lower joint 3, for example, by a fine-thread sealed connection, or a sealing member such as a sealant or a sealing gasket may be provided at the connection position between the two.

[0052] Among them, the inner diameter of the outer sleeve 10 is larger than the outer diameter of the lower joint 3, the outer sleeve 10 is sleeved on the outside of the lower joint 3, and the other end of the outer sleeve 10 is sealed with the outer wall of the lower joint 3. The other end of the outer sleeve 10 and the outer wall of the lower joint 3 can be sealed by setting a sealing member, or can be sealed by interference fit. Since the lower joint 3 and the connector 2 are also sealed, the accommodating cavity 101 can be formed between the inner wall of the outer sleeve 10 and the outer wall of the lower joint 3. Alternatively, in order to further separate the space between the outer sleeve 10 and the lower joint 3 to form the accommodating cavity 101, a protruding structure can be provided on the outer wall of the lower joint 3, and the protruding structure can be sealed with the inner wall of the outer sleeve 10, so as to achieve the effect of sealing. Figure 1 As shown, an accommodating cavity 101 is formed by the end of the outer sleeve 10 that cooperates with the lower joint 3 , the protrusion, the inner wall of the outer sleeve 10 and the outer wall of the lower joint 3 .

[0053] In a specific implementation, the sliding sleeve 9 is connected to the upper joint 1 by penetrating a shear pin (not shown in the figure).

[0054] Specifically, the method of fixing the sleeve 9 at a specified position by means of shear pins is temporary fixing, and the purpose is that after the toe sleeve enters the well, the sleeve 9 can shear the shear pins and move downward under the action of liquid pressure, thereby achieving the purpose of opening the liquid outlet 11. The number and setting positions of the shear pins can be selected and set according to the actual design and use requirements.

[0055] like Figure 1 and Figure 2 As shown, in a specific implementation, the connector 2 forms a first-step hole 23, a second-step hole 24 and a third-step hole 25 with decreasing apertures from the upper end to the lower end, and forms a first step 26 and a second step 27, and the connection port 21 is located at the first step 26;

[0056] A limiting ring 91 is disposed on the outer wall of the sleeve 9. The limiting ring 91 is sleeved in the first step hole 23. When the connecting port 21 is connected to the port 32, well fluid flows out through the connecting port 21 to apply pressure to the limiting ring 91 to make the sleeve 9 slide, and the second step 27 limits the limiting ring 91.

[0057] Specifically, the upper end of the upper joint 1 is a female head and the lower end is a male head. The inner wall of the first step hole 23 of the connecting head 2 is provided with threads to form a female head. The upper joint 1 and the connecting head 2 are threadedly connected, and the lower end of the upper joint 1 is a preset distance from the first step 26.

[0058] The pressure-conducting channel 22 may extend vertically from the lower end of the connector 2 to the upper end, and open at the position of the first step 26 to form a connecting port 21 .

[0059] It should be noted that a preset distance needs to be left between the connecting port 21 and the lower end of the upper joint 1 to ensure that when the port 32 is connected to the connecting port 21, the well fluid can flow out of the connecting port 21 through the port 32 and the pressure-conducting channel 22 at one time, and then act on the limiting ring 91 on the outer wall of the sleeve 9, and then under the action of the well fluid pressure, the sleeve 9 shears the shear pin and slides downward, and finally the sleeve 9 slides down to the position where the limiting ring 91 contacts and limits the second step 27, opens the blocked liquid outlet 11, and completes the opening of the sleeve 9.

[0060] like Figure 1As shown, in a specific implementation, the inner and outer walls of the lower end of the connector 2 are both provided with threads, the upper end of the lower joint 3 is a male head and is connected to the internal thread of the lower end of the connector 2; the top end of the outer sleeve 10 is a female head and is connected to the external thread of the lower end of the connector 2.

[0061] Specifically, by providing threads on the inner and outer walls of the lower end of the connector 2, connecting the lower joint 3 with the inner threads, and connecting the outer sleeve 10 with the outer threads, it is possible to ensure that the outer sleeve 10 is sleeved on the outside of the lower joint 3 while ensuring that the outer sleeve 10 and the outer wall of the connector 2 form a uniform outer diameter, and thus the outer diameters of the outer sleeve 10, the connector 2 and the upper joint 1 are the same to form a toe-end sliding sleeve with a smooth outer wall.

[0062] In a specific implementation, the number of flow channels formed by the connection port 21 and the pressure-conducting channel 22 is multiple, and the multiple flow channels are evenly spaced and arranged around the side wall of the connector 2 .

[0063] Specifically, the number of flow channels formed by the connecting port 21 and the pressure-conducting channel 22 may be 3, 4, 5, 6, 7, 8, or more, and a suitable number may be set according to design requirements.

[0064] Furthermore, since opening the sleeve 9 requires that the port 32 of the valve channel 31 be connected to the connecting port 21 and that the liquid can enter the connected channel from the port 32, when the number of flow channels formed by the connecting port 21 and the pressure-conducting channel 22 is multiple, it is preferred that the number of valve channels 31 be set to multiple, and the valve channels 31 be evenly spaced in the side wall of the lower joint 3, a control valve 4 be provided in each valve channel 31, and a soluble plug 5 be blocked at the port 32 of each valve channel 31, and the multiple valve channels 31 be respectively connected to the multiple flow channels; wherein all the control valves 4 are connected to the electronic control module 7.

[0065] In a specific implementation, the soluble plug 5 is made of a material that can be dissolved in acid; or, the soluble plug 5 is made of a material that can be dissolved in alkali; or the soluble plug 5 can be a water-soluble material, and the specific material is known to the technicians, but it should be noted that the soluble plug 5 made of water-soluble material needs to be guaranteed to be completely dissolved after a period of time, so that the soluble plug 5 loses its sealing function.

[0066] Specifically, the soluble plug 5 can be made of calcium carbonate that can be dissolved in acid, or can be made of aluminum alloy that can be dissolved in alkali. In addition, the material of the soluble plug 5 can also be selected by technicians according to conventional materials, and this application does not limit it.

[0067] Embodiment 2

[0068] A second embodiment of the present invention provides a method for controlling the opening of a sleeve, which is used for the above-mentioned toe sleeve. The method includes:

[0069] 201. Use a preset liquid to dissolve the soluble plug, or wait for the soluble plug to dissolve on its own after a preset time in the well.

[0070] Specifically, this step can be performed according to the material of the soluble plug on the toe sleeve, that is, if the soluble plug is made of a material that can be dissolved in acid, then when the sleeve needs to be opened, acid is first injected into the well to dissolve the soluble plug; or, if the soluble plug is made of a material that can be dissolved in alkali, then when the sleeve needs to be opened, alkali is first injected into the well to dissolve the soluble plug; or, if the soluble plug is made of a water-soluble material, the soluble plug can be waited for to dissolve in the well in a shape of a letter, and the specific time required for the dissolution can be set by the technician by adjusting the water-soluble material of the soluble plug.

[0071] 202. Apply a preset pressure wave code pressure to the well, and transmit a preset pressure wave code signal through the well fluid.

[0072] Specifically, the purpose of this step is to transmit a preset pressure wave code signal to the well. Since there is well fluid in the well, pressure can be applied to the well through a pressure-applying device (which is a device commonly used in oil and gas production and will not be described here), and pressure is applied using a preset pressure wave code. The pressure then acts on the well fluid and is transmitted through the well fluid to the pressure sensor at the toe sleeve.

[0073] Among them, the preset pressure wave code is set by the staff and is a specific combination of pressure wave codes. It is very different from the pressure change during the casing test, and can effectively prevent the toe end sliding sleeve from being accidentally opened during the casing pressure test.

[0074] 203. Collect and compare the preset pressure wave code. When the preset pressure wave code is consistent with the pre-stored pressure wave code, open the control valve of the toe end sleeve, connect the connecting port of the toe end sleeve with the port, so that the well fluid enters and pushes the sleeve downward, and opens the liquid outlet of the toe end sleeve.

[0075] Specifically, the preset pressure wave code transmitted by the well fluid is collected by the pressure sensor of the toe end sleeve, and then compared with the pressure wave code pre-stored in the electronic control module for comparison. If the collected pressure wave code is the same as the pre-stored pressure wave code, the electronic control module controls the control valve to open, connects the valve channel and the port, and then connects the connecting port and the port, so that the well fluid can enter from the port, flow through the valve channel and the pressure conducting channel to the connecting port in sequence, and the well fluid acts on the sleeve, and combined with the effect of the well fluid in the through hole in the middle part of the toe end sleeve on the sleeve, the shear pin of the sleeve is cut off and slides downward, thereby exposing the liquid outlet, that is, the liquid outlet is connected with the through hole in the middle part of the toe end sleeve, and the opening of the sleeve is completed.

[0076] Specifically, the toe end sliding sleeve described in the second embodiment can directly use the toe end sliding sleeve provided in the first embodiment. The specific implementation structure can refer to the relevant content described in the first embodiment, which will not be repeated here.

[0077] The sleeve opening control method of the embodiment of the present invention applies a preset pressure wave code pressure to the well as a signal to open the sleeve. When the pressure sensor detects the preset pressure wave code, it transmits the pressure signal to the electronic control module, and the electronic control module controls the control valve to open, thereby connecting the port with the connecting port. At this time, the liquid in the middle channel of the toe sleeve can enter from the port and flow out from the connecting port. Under the action of the liquid, the sleeve can be pushed downward. For example, a protrusion or a groove can be set on the side wall of the sleeve, so that the well fluid pushes the protrusion or the groove to push the sleeve, thereby opening the liquid outlet blocked by the sleeve and completing the opening action of the toe sleeve. It can be seen that the method of the present application controls the opening of the sleeve by the pressure wave code signal, which can effectively avoid the occurrence of misoperation opening and failure to open normally.

[0078] It is understandable that the related features in the above devices can be referenced to each other. In addition, the "first", "second" and the like in the above embodiments are used to distinguish the various embodiments, and do not represent the advantages and disadvantages of the various embodiments.

[0079] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known structures and technologies are not shown in detail so as not to obscure the understanding of this description.

[0080] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A toe end sliding sleeve, characterized in that: include: The upper joint, the connecting joint, and the lower joint are connected in sequence to form a hollow pipe structure; Wherein, the side wall of the upper joint is provided with a liquid outlet, the inner wall of the connector is provided with a connecting port, and the side wall of the connector is provided with a pressure-conducting channel connecting the lower end of the connector and the connecting port; the side wall of the lower joint is provided with a valve channel, one end of the valve channel extends to a position connected with the pressure-conducting channel, and the other end of the valve channel extends to the inner wall of the lower joint to form a port, a control valve is provided in the valve channel, and a soluble plug is provided at the port, a battery and an electronic control module are provided in the side wall of the lower joint, the battery, the electronic control module and the control valve are electrically connected, a pressure sensor is provided on the inner wall of the lower joint, and the pressure sensor is connected to the electronic control module; A sliding sleeve, the upper end of which is sleeved inside the upper joint to seal the liquid outlet, and the lower end of which is sleeved inside the connector to seal the connector; Wherein, after the soluble plug is dissolved, when the pressure sensor receives a preset pressure wave code and transmits a pressure signal to the electronic control module, the electronic control module can control the control valve to open based on the pressure signal, and the connecting port is connected with the port; The connector is formed with a first-step hole, a second-step hole and a third-step hole with decreasing apertures from the upper end to the lower end, and a first step and a second step, and the connector is located at the first step; A limiting ring is provided on the outer wall of the sleeve, and the limiting ring is sleeved in the first step hole. When the connecting port is connected with the port, well fluid flows out through the connecting port and applies pressure to the limiting ring to make the sleeve slide, and the second step limits the limiting ring. The connecting port and the pressure-conducting channel form a plurality of flow channels, and the plurality of flow channels are evenly spaced and arranged around the side wall of the connector.

2. The toe end sliding sleeve according to claim 1, characterized in that: Also includes: The outer sleeve is connected to the connector and is sleeved on the outer side of the lower connector. The outer sleeve and the lower connector form a sealed accommodating cavity in which the battery and the electric control module are arranged.

3. The toe end sliding sleeve according to claim 2, characterized in that: The sliding sleeve is connected to the upper joint by penetrating shear pins.

4. The toe end sliding sleeve according to claim 3, characterized in that: The upper end of the upper joint is a female head and the lower end is a male head. The inner wall of the first step hole of the connecting head is provided with threads to form a female head. The upper joint and the connecting head are threadedly connected. The lower end of the upper joint is a preset distance from the first step.

5. The toe end sliding sleeve according to claim 4, characterized in that: The inner and outer walls of the lower end of the connector are both provided with threads, and the upper end of the lower connector is a male connector and is connected to the internal threads of the lower end of the connector; The top end of the outer sleeve is a female head and is connected to the external thread at the lower end of the connector.

6. The toe end sliding sleeve according to claim 1, characterized in that: The valve channels are multiple in number and are evenly spaced in the side wall of the lower joint. Each valve channel is provided with a control valve. The port of each valve channel is blocked with the soluble plug. The multiple valve channels are respectively connected to multiple flow channels. Wherein, all the control valves are connected to the electronic control module.

7. The toe end sliding sleeve according to claim 1, characterized in that: The soluble plug is made of a material that can be dissolved in acid; Alternatively, the soluble plug is made of a material that can be dissolved in alkali solution.

8. A method for controlling the opening of a sleeve, used for a toe sleeve as claimed in any one of claims 1 to 7, characterized in that: include: Using a preset liquid to dissolve the soluble plug, or waiting for the soluble plug to dissolve itself after a preset time in the well; Applying a preset pressure wave code pressure into the well, and transmitting a preset pressure wave code signal through the well fluid; The preset pressure wave code is collected and compared. When the preset pressure wave code is consistent with the pre-stored pressure wave code, the control valve of the toe end sleeve is opened to connect the connecting port of the toe end sleeve with the port, so that the well fluid enters and pushes the sleeve downward, and the liquid outlet of the toe end sleeve is opened.

Images