On-off cycle valve

Abstract

The application relates to a switch cycle valve, which comprises a barrel assembly, a limiting assembly and a reversing assembly. The barrel assembly comprises a body and a sliding sleeve, the sliding sleeve is elastically arranged in the body, the body is provided with a bypass hole, and the sliding sleeve is provided with a cycle hole. The limiting assembly comprises a limiting sleeve and a ball seat, and the ball seat is in abutment with the sliding sleeve. The limiting sleeve is fixedly connected with the body and is arranged outside the ball seat to limit the passing of an opening ball or a closing ball through the ball seat. The reversing assembly comprises a limiting pin shaft and a reversing part. The outer wall of the sliding sleeve is provided with the reversing part, and the limiting pin shaft is in sliding fit with the reversing part so that the sliding sleeve reaches a first position or a second position relative to the body under the action of pump pressure. When the sliding sleeve reaches the first position, the cycle hole and the bypass hole are mutually misaligned. When the sliding sleeve reaches the second position, the cycle hole and the bypass hole are in communication. Only one closing ball is needed to close the bypass hole, the number of balls is smaller, the single operation time of a drilling tool after entering a well can be prolonged, and the operation efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of drilling tool technology, and in particular to a switching circulation valve. Background Technology

[0002] In the exploration and development of oil and gas fields, horizontal wells and extended reach wells are becoming increasingly common, leading to greater complexity of the formations encountered and increasing drilling difficulty. This necessitates high-volume well cleaning, flushing, and plugging operations. Because the drill string assemblies for horizontal and extended reach wells often include downhole power tools and downhole measuring instruments, to avoid damage to these instruments during well cleaning, flushing, and plugging operations, the original drill string is generally not used for high-volume operations. Instead, the original drill string is pulled up, and tools without testing instruments and downhole equipment are replaced for plugging and flushing. This cyclical process increases non-drilling time, reduces drilling efficiency, and increases operating costs.

[0003] In related technologies, some downhole tools (such as switching valves) control the opening and closing of their working channels by dropping balls. Therefore, a dedicated ball collector is required, and the number of drops is limited by the length of the collector. Considering operational requirements, the ball collector cannot be extended indefinitely; the number of balls dropped and the length of the collector must be specified. Typically, one work cycle involves dropping one opening ball at the wellhead to open the working channel and two closing balls to close it. However, using two closing balls to close the downhole tool's working channel, limited by the length of the ball collector, results in a shorter downhole tool operation time, impacting operational efficiency. Utility Model Content

[0004] This application provides a switching circulation valve to solve the technical problem that existing downhole tools use two shut-off balls to close the working channel, which limits the operation time of the downhole tools due to the length of the ball collector, thus affecting the operation efficiency.

[0005] This application provides a switching circulation valve, comprising:

[0006] The cylinder assembly includes a body and a sliding sleeve. The sliding sleeve is elastically disposed within the body. The body is provided with a bypass hole, and the sliding sleeve is provided with a circulation hole.

[0007] A limiting component is disposed within the main body. The limiting component includes a limiting sleeve and a ball seat. The ball seat can seal with the opening ball or closing ball. The ball seat abuts against the sliding sleeve so that the ball seat pushes the sliding sleeve relative to the main body under the action of pump pressure. The end of the ball seat near the sliding sleeve can expand outward under the action of pump pressure. The limiting sleeve is fixedly connected to the main body and is disposed on the outside of the ball seat to restrict the opening ball or closing ball from passing through the ball seat.

[0008] A reversing assembly is disposed between the body and the sliding sleeve. The reversing assembly includes a limiting pin and a reversing part. The outer wall of the sliding sleeve is provided with the reversing part. The limiting pin and the reversing part are slidably engaged so that the sliding sleeve reaches a first position or a second position relative to the body under the action of pump pressure.

[0009] Specifically, when the sliding sleeve reaches the first position, the circulation hole and the bypass hole are misaligned to close the bypass hole; when the sliding sleeve reaches the second position, the circulation hole and the bypass hole are connected to open the bypass hole.

[0010] In one possible implementation, the reversing part is disposed on the outer wall of the sliding sleeve. The reversing part is a closed groove arranged around the circumferential direction of the sliding sleeve. One end of the limiting pin is connected to the body, and the other end of the limiting pin is slidably engaged with the reversing part.

[0011] Alternatively, the reversing part is located on the inner side wall of the main body. The reversing part is a closed groove arranged around the circumference of the main body. One end of the limiting pin is connected to the sliding sleeve, and the other end of the limiting pin is slidably engaged with the reversing part.

[0012] In one possible implementation, the reversing unit has a closed position, a first limit position, a first reversing position, an open position, a second limit position, and a second reversing position that are sequentially connected. The first reversing position is located between the first limit position and the open position, and the second reversing position is located between the second limit position and the closed position.

[0013] In one possible implementation, an inner limiting step is provided at the end of the ball seat near the sliding sleeve, and the inner limiting step is sealed to the opening ball or the closing ball.

[0014] A slot is provided at one end of the ball seat near the sliding sleeve. The slot extends from one end of the ball seat near the sliding sleeve to the other end of the ball seat and connects with the inner limiting step, so that the end of the ball seat near the sliding sleeve can expand outward under the action of pump pressure.

[0015] In one possible implementation, the limiting sleeve is provided with a limiting groove, and the ball seat is provided with an outer limiting step at the end near the sliding sleeve, the outer limiting step abutting against the limiting groove.

[0016] In one possible implementation, a first expansion groove is provided at one end of the limiting sleeve near the sliding sleeve. The limiting groove has a first inner diameter, and the first expansion groove has a second inner diameter, wherein the first inner diameter is smaller than the second inner diameter.

[0017] In one possible implementation, a second expansion groove is provided at one end of the limiting sleeve near the sliding sleeve, and a first expansion groove is located between the limiting groove and the second expansion groove.

[0018] In one possible implementation, the inner side of the limiting sleeve is provided with a groove, and the outer side of the ball seat is provided with a boss that slides with the groove.

[0019] In one possible implementation, the reversing assembly also includes a spring, which is sleeved around the periphery of the slide sleeve. A shoulder is provided on the outer side of the slide sleeve, one end of the spring is connected to the shoulder, and the other end of the spring is connected to the body.

[0020] In one possible implementation, multiple seals are provided on the inner wall of the body, with the multiple seals respectively located on both sides of the bypass hole.

[0021] The technical solutions provided in this application have the following advantages compared with the prior art:

[0022] The switching circulation valve provided in this application embodiment is attached to the drill pipe or other tools and then extended downhole. The end of the valve body closer to the wellhead is the upper part, and the end of the valve body further away from the wellhead is the lower part. A closing ball is inserted into the internal channel of the ball seat from the wellhead. The closing ball and the ball valve achieve a sealed connection. The hydraulic pressure above the ball seat rises rapidly, forming a driving force that pushes the ball seat and the sliding sleeve downward. This causes the ball valve to move the sliding sleeve downward relative to the valve body. During the downward movement of the ball valve, the end of the ball seat closer to the sliding sleeve can expand outward under the pump pressure, allowing the closing ball to pass through the ball valve. The internal channel of the ball valve opens, the downward pressure of the ball valve on the sliding sleeve disappears, and the sliding sleeve moves upward under the action of elastic restoring force. Under the limiting action of the limiting pin, the sliding sleeve reaches the first position, and the circulation hole and the bypass hole are misaligned to close the bypass hole, thus closing the working channel. Compared to structures that use two shut-off balls to close downhole tools, the switching circulation valve provided in this application requires fewer balls. With the same number of opening and closing cycles, the overall length of the downhole tool is shorter. With the same ball collector length, this increases the single-operation time after the drilling tool enters the well, improving operational efficiency. Simultaneously, the reversing assembly simplifies the reversing process, reduces tool complexity, and improves operational reliability. Attached Figure Description

[0023] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0026] Figure 1 This is a schematic diagram of the structure of a switching circulation valve provided in an embodiment of this application;

[0027] Figure 2 for Figure 1 The diagram shows the working principle of the switching circulation valve. Figure 1 ;

[0028] Figure 3 for Figure 1 The diagram shows the working principle of the switching circulation valve. Figure 2 ;

[0029] Figure 4 for Figure 1 The diagram shows the working principle of the switching circulation valve. Figure 3 ;

[0030] Figure 5 for Figure 1 A schematic diagram of the structure of the main body of the switching circulation valve is shown;

[0031] Figure 6 for Figure 1 The diagram shows the structure of the sliding sleeve of the switching circulation valve;

[0032] Figure 7 This is a schematic diagram of the unfolded reversing section provided in an embodiment of this application;

[0033] Figure 8 for Figure 1 The diagram shows the structure of the ball seat of the switching circulation valve;

[0034] Figure 9 for Figure 8 The bottom view of the ball seat is shown;

[0035] Figure 10 for Figure 1 The diagram shows the structure of the limit sleeve of the switching circulation valve.

[0036] Explanation of reference numerals in the attached figures:

[0037] X, axial direction; Y, radial direction; R, circumferential direction;

[0038] 100. Switch the circulation valve;

[0039] 10. Cylinder assembly; 11. Body; 111. Bypass hole; 112. Seal; 113. Nozzle; 114. First internal thread; 12. Sliding sleeve; 121. Circulation hole; 122. Shoulder;

[0040] 20. Limiting component; 21. Limiting sleeve; 211. Limiting groove; 212. First expansion groove; 213. Second expansion groove; 214. Slide groove; 22. Ball seat; 221. Inner limiting step; 222. Slot; 223. Outer limiting step; 224. Boss; 225. Through groove;

[0041] 30. Reversing assembly; 31. Limit pin; 32. Reversing part; 321. Closed position; 322. First limit position; 323. First reversing position; 324. Open position; 325. Second limit position; 326. Second reversing position; 33. Spring;

[0042] 200, Open the ball; 300, Close the ball. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0044] The following disclosure provides numerous different embodiments or examples for implementing various structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed.

[0045] For ease of description, spatial relative terms may be used in the text to describe the relative position or movement of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "front," "back," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure undergoes a positional flip, orientation change, or change of motion, these directional indications will change accordingly. For instance, an element described as "below other elements or features" or "below other elements or features" will subsequently be oriented "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.

[0046] In related technologies, some downhole tools (such as switching valves) control the opening and closing of their working channels by dropping balls. Therefore, a dedicated ball collector is required, and the number of drops is limited by the length of the collector. Considering operational requirements, the ball collector cannot be extended indefinitely; the number of balls dropped and the length of the collector must be specified. Typically, one work cycle involves dropping one opening ball at the wellhead to open the working channel and two closing balls to close it. However, using two closing balls to close the downhole tool's working channel, limited by the length of the ball collector, results in a shorter downhole tool operation time, impacting operational efficiency.

[0047] To address the problem in existing downhole tools that use two shut-off balls to close the working channel, which limits the tool's operating time and impacts efficiency due to the length of the ball collector, this application provides a switching circulation valve. This valve requires fewer balls, resulting in a shorter overall length of the downhole tool for the same number of opening and closing cycles. With the same ball collector length, it increases the single-cycle operating time after the drilling tool enters the well, thus improving efficiency. Simultaneously, the reversing assembly simplifies the reversing process, reduces tool complexity, and enhances operational reliability.

[0048] like Figure 1 As shown, this application embodiment provides a switching circulation valve 100, including a cylindrical assembly 10, a limiting assembly 20, and a reversing assembly 30. The cylindrical assembly 10 includes a body 11 and a sliding sleeve 12. Both the body 11 and the sliding sleeve 12 are cylindrical components with openings at both ends. The sliding sleeve 12 is elastically disposed inside the body 11. The body 11 is provided with a bypass hole 111, and the side wall of the sliding sleeve 12 is provided with a circulation hole 121.

[0049] The limiting component 20 is disposed inside the body 11. The limiting component 20 includes a limiting sleeve 21 and a ball seat 22. The ball seat 22 can be sealed and engaged with the opening ball 200 or the closing ball 300. The ball seat 22 abuts against the sliding sleeve 12 so that the ball seat 22 pushes the sliding sleeve 12 to move relative to the body 11 under the action of pump pressure. The end of the ball seat 22 near the sliding sleeve 12 can expand outward under the action of pump pressure. The limiting sleeve 21 is fixedly connected to the body 11. The limiting sleeve 21 is disposed on the outside of the ball seat 22 and is used to restrict the opening ball 200 or the closing ball 300 from passing through the ball seat 22.

[0050] A reversing assembly 30 is disposed between the body 11 and the sliding sleeve 12. The reversing assembly 30 includes a limiting pin 31 and a reversing part 32. The outer side wall of the sliding sleeve 12 is provided with the reversing part 32. The limiting pin 31 and the reversing part 32 are slidably engaged so that the sliding sleeve 12 reaches a first position or a second position relative to the body 11 under the action of pump pressure. When the sliding sleeve 12 reaches the first position, the circulation hole 121 and the bypass hole 111 are misaligned to close the bypass hole 111. When the sliding sleeve 12 reaches the second position, the circulation hole 121 and the bypass hole 111 are connected to open the bypass hole 111.

[0051] For ease of explanation and understanding, the axial direction of the body 11 can be the X direction shown in the figure. The switching circulation valve 100 provided in this embodiment is attached to the drill pipe or other tools and then extended downhole, with the end of the body 11 closer to the wellhead above and the end of the body 11 further from the wellhead below. Initially, the switching circulation valve 100 is in the first state, such as... Figure 1 As shown, the circulation hole 121 is located upstream of the bypass hole 111. The circulation hole 121 and the bypass hole 111 are offset from each other, with the bypass hole 111 in a closed state. Simultaneously, the sliding sleeve 12 is in the first position relative to the body 11. If the drill pipe or other tools encounter well leakage, the drill string is first pulled to a safe section. Then, the opening ball 200 is inserted from the wellhead into the internal channel of the ball seat 22. The limiting sleeve 21 can restrict the opening ball 200 from passing through the ball seat 22. Figure 2As shown, the opening ball 200 and the ball valve reach a sealed connection, temporarily blocking the flow of drilling fluid and creating pressure. The surface mud pump continues to pump drilling fluid, causing the hydraulic pressure above the ball seat 22 to rise rapidly, forming a driving force that pushes the ball seat 22 and the sliding sleeve 12 downwards. This causes the ball valve to move the sliding sleeve 12 relative to the body 11, and the ball valve and the sliding sleeve 12 move downwards along the axial direction of the body 11. During the downward movement of the ball valve, the end of the ball seat 22 near the sliding sleeve 12 can expand outwards under the pump pressure, allowing the opening ball 200 to pass through the ball valve. The internal passage of the ball valve opens, the downward pressure of the ball valve on the sliding sleeve 12 disappears, and the sliding sleeve 12 moves upwards under the action of the elastic restoring force. Under the limiting action of the limiting pin 31, the sliding sleeve 12 reaches the second position. At this time, the circulation hole 121 is connected to the bypass hole 111 to open the bypass hole 111. A working channel is formed between the circulation hole 121 and the bypass hole 111. The working channel is open, as... Figure 3 As shown, the switching circulation valve 100 is in the second state at this time, thereby realizing the switching circulation valve 100 from the first state to the second state.

[0052] In the second state, such as Figure 4 As shown, a shut-off ball 300 is inserted into the internal channel of the ball seat 22 from the wellhead. The shut-off ball 300 and the ball valve achieve a sealed connection, and pressure is applied. The hydraulic pressure above the ball seat 22 rises rapidly, creating a driving force that pushes the ball seat 22 and the sliding sleeve 12 downwards. This causes the ball valve to move the sliding sleeve 12 downwards relative to the body 11. During the downward movement of the ball valve, the end of the ball seat 22 near the sliding sleeve 12 expands outwards under the pump pressure, allowing the shut-off ball 300 to pass through the ball valve. The internal channel of the ball valve opens, the downward pressure of the ball valve on the sliding sleeve 12 disappears, and the sliding sleeve 12 moves upwards under the action of the elastic restoring force. Under the limiting action of the limiting pin 31, the sliding sleeve 12 reaches the first position, and the circulation hole 121 and the bypass hole 111 are misaligned to close the bypass hole 111, thus closing the working channel. Figure 1 As shown, the switching circulation valve 100 is in the first state at this time, thereby switching the switching circulation valve 100 from the first state to the second state. The switching circulation valve 100 provided in this application can open the working channel with only one opening ball 200 and close the working channel with only one closing ball 300. Compared with the structure that uses two closing balls 300 to close the downhole tool, the switching circulation valve 100 provided in this application requires fewer balls. Under the same number of opening and closing times, the overall length of the downhole tool is shorter. With the same length of ball collector, it can increase the single operation time after the drilling tool enters the well, thereby improving operation efficiency. At the same time, the reversing component 30 can simplify the reversing process, reduce tool complexity, and improve the reliability of operation.

[0053] In one embodiment, such as Figure 5As shown, the limiting sleeve 21 and the body 11 are fixedly connected by threads. Specifically, the inner sidewall of the upper part of the body 11 is provided with a first internal thread 114, and the outer sidewall of the limiting sleeve 21 is provided with a first external thread that mates with the first internal thread 114, thereby achieving a fixed connection between the two.

[0054] In one embodiment, the upper and lower parts of the body 11 are respectively provided with second internal threads, thereby facilitating the connection of external parts (such as drill rods, ball collectors, etc.).

[0055] Conventional downhole tools use composite balls, which wear down after each opening and closing operation and cannot be reused. The opening ball 200 and closing ball 300 provided in this embodiment can be made of steel balls, allowing for reuse.

[0056] In one embodiment, such as Figure 1 and Figure 6 As shown, the reversing part 32 is disposed on the outer wall of the sliding sleeve 12. The reversing part 32 is a closed groove arranged around the circumference of the sliding sleeve 12. One end of the limiting pin 31 is connected to the body 11, and the other end of the limiting pin 31 is slidably engaged with the reversing part 32. Because the limiting pin 31 is slidably engaged with the reversing part 32, the sliding sleeve 12 rotates and moves up and down relative to the body 11. Since the reversing part 32 is a closed groove arranged around the circumference of the sliding sleeve 12, the sliding sleeve 12 can be cyclically switched between the first position and the second position.

[0057] Specifically, the circumferential direction of the sliding sleeve 12 can be the R direction shown in the figure. It can be understood that in the first state, when the opening ball 200 is engaged, the hydraulic pressure above the ball seat 22 rapidly increases, creating a driving force that pushes the ball seat 22 and the sliding sleeve 12 downwards. The ball valve causes the sliding sleeve 12 to move downwards relative to the body 11. Due to the sliding engagement of the limiting pin 31 with the reversing part 32, the sliding sleeve 12 rotates and moves downwards relative to the body 11. During the downward movement of the ball valve, the end of the ball seat 22 near the sliding sleeve 12 expands outwards under the pump pressure. The opening ball 200 passes through the ball valve, opening the internal passage of the ball valve. The downward pressure of the ball valve on the sliding sleeve 12 disappears, and the sliding sleeve 12 rotates and moves upwards under the action of the elastic restoring force. Under the limiting action of the limiting pin 31, the sliding sleeve 12 reaches the second position. At this time, the circulation hole 121 connects with the bypass hole 111, and the working passage is opened. Similarly, in the second state, when the closing ball 300 is engaged, the closing ball 300 and the ball valve achieve a sealed connection. The hydraulic pressure above the ball seat 22 rapidly increases, generating a driving force that pushes the ball seat 22 and the sliding sleeve 12 downwards. The ball valve causes the sliding sleeve 12 to move downwards relative to the body 11. During the downward movement of the ball valve, the end of the ball seat 22 near the sliding sleeve 12 can expand outwards under the pump pressure, allowing the closing ball 300 to pass through the ball valve. The internal passage of the ball valve opens, the downward pressure of the ball valve on the sliding sleeve 12 disappears, and the sliding sleeve 12 rotates and moves upwards under the action of the elastic restoring force. Under the limiting action of the limiting pin 31, the sliding sleeve 12 reaches the first position, the circulation hole 121 and the bypass hole 111 are misaligned, and the working passage is closed.

[0058] In another embodiment not shown in the figure, the reversing part 32 is disposed on the inner sidewall of the body 11. The reversing part 32 is a closed groove arranged around the body 11 in the circumferential direction. One end of the limiting pin 31 is connected to the sliding sleeve 12, and the other end of the limiting pin 31 is slidably engaged with the reversing part 32. The working principle can be referred to the above embodiment, and will not be repeated here.

[0059] In one embodiment, such as Figure 7As shown, the reversing part 32 has a closing point 321, a first limiting point 322, a first reversing point 323, an opening point 324, a second limiting point 325, and a second reversing point 326 that are sequentially connected along the circumferential direction of the sliding sleeve 12. The closing point 321, the first limiting point 322, the first reversing point 323, the opening point 324, the second limiting point 325, and the second reversing point 326 are sequentially connected along the circumferential direction of the sliding sleeve 12 to form a closed groove. Specifically, the closing point 321 has the lowest height, the opening point 324 is higher than the closing point 321, the first limiting point 322 and the second limiting point 325 are both higher than the opening point 324, the first reversing point 323 is located between the first limiting point 322 and the opening point 324, and the second reversing point 326 is located between the second limiting point 325 and the closing point 321. Of course, there can be multiple of the above-mentioned points. The closing point 321, the first limit point 322, the first reversing point 323, the opening point 324, the second limit point 325, and the second reversing point 326 form a set of switch points. In other words, multiple sets of switch points can be set in the reversing part 32.

[0060] Specifically, in the first state, the opening ball 200 is engaged, and the opening ball 200 and the ball valve are in a sealed connection. The hydraulic pressure above the ball seat 22 rises rapidly, forming a driving force that pushes the ball seat 22 and the sliding sleeve 12 downward. The ball valve drives the sliding sleeve 12 to move downward relative to the body 11. Because the limiting pin 31 slides in the reversing part 32, the sleeve 12 rotates and moves downward relative to the body 11. When the limiting pin 31 moves from the closed position 321 to the first limiting position 322, the end of the ball seat 22 near the sleeve 12 can expand outward under the action of pump pressure. The opening ball 200 passes through the ball valve, the internal channel of the ball valve opens, the downward pressure of the ball valve on the sleeve 12 disappears, and the sleeve 12 rotates and moves upward under the action of elastic restoring force. The limiting pin 31 can move from the first limiting position 322 through the first reversing position 323 to the opening position 324. At this time, the limiting pin 31 plays a limiting role on the sleeve 12, and the sleeve 12 cannot continue to move upward and stops at the second position. The circulation hole 121 is connected to the bypass hole 111, and the working channel is opened.

[0061] Similarly, in the second state, when the closing ball 300 is engaged, the closing ball 300 and the ball valve are in a sealed connection state. The hydraulic pressure above the ball seat 22 rises rapidly, forming a driving force that pushes the ball seat 22 and the sliding sleeve 12 downward. The ball valve drives the sliding sleeve 12 to move downward relative to the body 11. Because the limiting pin 31 slides in the reversing part 32, the sleeve 12 rotates and moves downward relative to the body 11. When the limiting pin 31 moves from the opening position 324 to the second limiting position 325, the end of the ball seat 22 near the sleeve 12 can expand outward under the action of pump pressure, so that the closing ball 300 passes through the ball valve. The internal passage of the ball valve opens, the downward pressure of the ball valve on the sleeve 12 disappears, and the sleeve 12 rotates and moves upward under the action of elastic restoring force. The limiting pin 31 can move from the second limiting position 325 through the second reversing position 326 to the closing position 321. At this time, the limiting pin 31 plays a limiting role on the sleeve 12. The sleeve 12 cannot continue to move upward and stops at the first position. The circulation hole 121 and the bypass hole 111 are misaligned, and the working channel is closed.

[0062] In one embodiment, such as Figure 8 and Figure 9 As shown, the ball seat 22 has an inner limiting step 221 at one end near the sliding sleeve 12. The inner diameter of the inner limiting step 221 is smaller than the diameter of the opening ball 200. The inner limiting step 221 is sealed to the opening ball 200 or the closing ball 300. The inner limiting step 221 is located on the inner surface of the ball seat 22 and protrudes inward along the radial direction of the ball seat 22. The radial direction of the ball seat 22 can be the Y direction shown in the figure. The ball seat 22 has a slot 222 at one end near the sliding sleeve 12. The slot 222 extends from one end of the ball seat 22 near the sliding sleeve 12 to the other end of the ball seat 22 and connects with the inner limiting step 221, so that the end of the ball seat 22 near the sliding sleeve 12 can expand outward under the action of pump pressure. The slots 222 can be set to two, three, four, etc., and this application does not impose specific limitations on them. For example, in this embodiment, four slots 222 are provided, and the four slots 222 are evenly arranged along the circumferential direction of the ball seat 22. By setting the slots 222, the end of the ball seat 22 near the sliding sleeve 12 has the ability to expand outward. When the limiting pin 31 moves from the closed position 321 to the first limiting position 322, the end of the ball seat 22 near the sliding sleeve 12 can expand outward under the action of pump pressure; or, when the limiting pin 31 moves from the open position 324 to the second limiting position 325, the end of the ball seat 22 near the sliding sleeve 12 can expand outward under the action of pump pressure.

[0063] Furthermore, such as Figure 8 As shown, the ball seat 22 is also provided with multiple through slots 225, which are connected one-to-one with the slots 222, thereby improving the elastic expansion capability of the ball seat 22.

[0064] In one embodiment, such as Figure 8 and Figure 10 As shown, the limiting sleeve 21 is provided with a limiting groove 211, and the ball seat 22 is provided with an outer limiting step 223 at one end near the sliding sleeve 12. The outer limiting step 223 is provided on the outer surface of the ball seat 22 and protrudes outward along the radial direction of the ball seat 22. The outer limiting step 223 abuts against the limiting groove 211, so that the limiting sleeve 21 provides pressure to the outer limiting step 223, restricting the expansion of the end of the ball seat 22 near the sliding sleeve 12. When the opening ball 200 or closing ball 300 is engaged, as the sliding sleeve 12 moves downward relative to the body 11, before the outer limiting step 223 disengages from the limiting groove 211, the limiting sleeve 21 always provides pressure to the outer limiting step 223, restricting the expansion of the end of the ball seat 22 near the sliding sleeve 12, thereby restricting the opening ball 200 or closing ball 300 from passing through the ball seat 22; until the limiting pin 31 reaches the first limiting point 322 from the closing point 321, or the limiting pin 31 reaches the second limiting point 325 from the opening point 324, the outer limiting step 223 disengages from the limiting groove 211, the pressure on the ball seat 22 disappears, and the end of the ball seat 22 near the sliding sleeve 12 can expand outward under the action of pump pressure, allowing the opening ball 200 or closing ball 300 to pass through the ball seat 22.

[0065] In one embodiment, such as Figure 10 As shown, the limiting sleeve 21 has a first expansion groove 212 at one end near the sliding sleeve 12. The limiting groove 211 has a first inner diameter D1, and the first expansion groove 212 has a second inner diameter D2, with the first inner diameter being smaller than the second inner diameter. When the opening ball 200 is inserted, the sliding sleeve 12 moves downward relative to the body 11, and the limiting pin 31 moves from the closing point 321 to the first limiting point 322. At the same time, the outer limiting step 223 disengages from the limiting groove 211 and reaches the first expansion groove 212. The pressure on the ball seat 22 disappears, and the end of the ball seat 22 near the sliding sleeve 12 can expand outward under the pump pressure, allowing the opening ball 200 to pass through the ball seat 22.

[0066] In one embodiment, such as Figure 10As shown, the end of the limiting sleeve 21 near the sliding sleeve 12 is provided with a second expansion groove 213, and the first expansion groove 212 is located between the limiting groove 211 and the second expansion groove 213. Optionally, the inner diameter of the second expansion groove 213 can be set as a second inner diameter; or, the second expansion groove 213 can have a third inner diameter D3, where the second inner diameter is smaller than the third inner diameter. When the closing ball 300 is engaged, the sliding sleeve 12 moves downward relative to the body 11, the limiting pin 31 moves from the opening point 324 to the second limiting point 325, and at the same time, the outer limiting step 223 disengages from the limiting groove 211 and reaches the second expansion groove 213. The pressure on the ball seat 22 disappears, and the end of the ball seat 22 near the sliding sleeve 12 can expand outward under the action of pump pressure, allowing the closing ball 300 to pass through the ball seat 22.

[0067] In one embodiment, such as Figure 8 and Figure 10 As shown, the inner side of the limiting sleeve 21 is provided with a sliding groove 214, and the outer side of the ball seat 22 is provided with a boss 224 that slides with the sliding groove 214. Through the sliding engagement of the boss 224 and the sliding groove 214, a sliding connection can be realized between the ball seat 22 and the limiting sleeve 21, and the ball seat 22 can reciprocate relative to the limiting sleeve 21.

[0068] In one embodiment, the reversing assembly 30 further includes a spring 33, which is sleeved around the periphery of the slide sleeve 12. The outer wall of the slide sleeve 12 is provided with a shoulder 122. One end of the spring 33 is fixedly connected to the shoulder 122, and the other end of the spring 33 is fixedly connected to the body 11. By providing the spring 33, the spring 33 can provide an elastic restoring force to the slide sleeve 12, thereby realizing the switching between the first position and the second position of the slide sleeve 12.

[0069] In one embodiment, such as Figure 5 As shown, multiple seals 112 are provided on the inner wall of the body 11. The multiple seals 112 are respectively provided on both sides of the bypass hole 111, which can prevent drilling fluid from leaking from the connection between the reversing pin and the body 11.

[0070] Optionally, such as Figure 5 As shown, the main body 11 is provided with a nozzle 113 at the bypass hole 111.

[0071] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a specific order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0072] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0073] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A switching circulation valve, characterized in that, include: A cylindrical assembly includes a body and a sliding sleeve, the sliding sleeve being elastically disposed within the body, the body being provided with a bypass hole, and the sliding sleeve being provided with a circulation hole; A limiting component is disposed within the main body. The limiting component includes a limiting sleeve and a ball seat. The ball seat is capable of sealingly engaging with an opening ball or a closing ball. The ball seat abuts against the sliding sleeve, so that the ball seat pushes the sliding sleeve relative to the main body under pump pressure, and the end of the ball seat near the sliding sleeve can expand outward under pump pressure. The limiting sleeve is fixedly connected to the main body and is disposed on the outside of the ball seat to restrict the opening ball or the closing ball from passing through the ball seat. A reversing assembly is disposed between the body and the sliding sleeve. The reversing assembly includes a limiting pin and a reversing part. The outer side wall of the sliding sleeve is provided with the reversing part. The limiting pin slides in cooperation with the reversing part so that the sliding sleeve reaches a first position or a second position relative to the body under the action of pump pressure. When the sliding sleeve reaches the first position, the circulation hole and the bypass hole are misaligned to close the bypass hole; when the sliding sleeve reaches the second position, the circulation hole and the bypass hole are connected to open the bypass hole.

2. The switching circulation valve according to claim 1, characterized in that, The reversing part is disposed on the outer side wall of the sliding sleeve. The reversing part is a closed groove arranged around the circumferential direction of the sliding sleeve. One end of the limiting pin is connected to the body, and the other end of the limiting pin is slidably engaged with the reversing part. Alternatively, the reversing part is disposed on the inner side wall of the body, and the reversing part is a closed groove arranged around the circumference of the body. One end of the limiting pin is connected to the sliding sleeve, and the other end of the limiting pin is slidably engaged with the reversing part.

3. The switching circulation valve according to claim 2, characterized in that, The reversing unit has a closed position, a first limiting position, a first reversing position, an open position, a second limiting position, and a second reversing position arranged in sequence. The first reversing position is located between the first limiting position and the open position, and the second reversing position is located between the second limiting position and the closed position.

4. The switching circulation valve according to claim 1, characterized in that, An inner limiting step is provided at one end of the ball seat near the sliding sleeve, and the inner limiting step is sealed to the opening ball or the closing ball; The ball seat has a slot at one end near the sliding sleeve. The slot extends from one end of the ball seat near the sliding sleeve to the other end of the ball seat and connects with the inner limiting step, so that the end of the ball seat near the sliding sleeve can expand outward under the action of pump pressure.

5. The switching circulation valve according to claim 4, characterized in that, The limiting sleeve is provided with a limiting groove, and the ball seat is provided with an outer limiting step at one end near the sliding sleeve, the outer limiting step abutting against the limiting groove.

6. The switching circulation valve according to claim 5, characterized in that, The limiting sleeve has a first expansion groove at one end near the sliding sleeve. The limiting groove has a first inner diameter, and the first expansion groove has a second inner diameter. The first inner diameter is smaller than the second inner diameter.

7. The switching circulation valve according to claim 6, characterized in that, The limiting sleeve is provided with a second expansion groove at one end near the sliding sleeve, and the first expansion groove is located between the limiting groove and the second expansion groove.

8. The switching circulation valve according to claim 1, characterized in that, The inner side of the limiting sleeve is provided with a sliding groove, and the outer side of the ball seat is provided with a boss that slides and engages with the sliding groove.

9. The switching circulation valve according to claim 1, characterized in that, The reversing assembly also includes a spring, which is sleeved around the periphery of the sliding sleeve. A shoulder is provided on the outer side of the sliding sleeve. One end of the spring is connected to the shoulder, and the other end of the spring is connected to the body.

10. The switching circulation valve according to claim 1, characterized in that, The inner wall of the body is provided with multiple sealing elements, which are respectively located on both sides of the bypass hole.

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