A method and device for infinitely activating a downhole bypass system switch with pressure control

Abstract

The present invention discloses a method and device for infinitely activating a downhole bypass system switch through pressure control, which includes an upper joint, a lower joint, a flow-through piston, a support spring, and a flow-through retaining ring. The flow-through piston has an upper cavity, a middle cavity, and a lower cavity that are sequentially connected; the upper joint and the lower joint are connected to form a bypass housing, and the lower end of the flow control hammer is fixed to the lower joint through the flow-through retaining ring; on the outer wall of the upper end of the flow-through piston, there are a plugging track, a circulation track, and a commutation track; a guiding system is provided in the commutation track; in the flow-through piston, there are a valve opening cavity and a valve closing cavity, and a valve opening system and a valve closing system are respectively provided in the valve opening cavity and the valve closing cavity; the valve opening system and the valve closing system respectively enable the guiding system to control the connection between the commutation track and the plugging track or the connection between the commutation track and the circulation track. The present invention realizes the purpose of infinitely switching the bypass valve through simple ground pressure control; compared with the bypass valve that requires ball dropping for valve opening and closing operations, it is more convenient and time-saving.

Description

Technical Field

[0001] The present invention relates to a method and device for infinitely activating a downhole bypass system switch by pressure control, belonging to the technical field of oil drilling. Background Art

[0002] During the drilling process, lost circulation often occurs. In order to reduce the tripping time, a common solution is to add a bypass valve in the drill string assembly for plugging without tripping. The bypass valve is generally installed in special drill string assemblies such as directional drilling, speed-up drilling, and measurement-while-drilling tools, such as above the MWD. It can be opened and closed in a timely manner according to downhole tools, increasing the applicability of special drill string assemblies, facilitating the improvement of production efficiency, and reducing the well control risk.

[0003] Currently, the most commonly used bypass valve on site is the ball-drop type. The bypass valve is activated by dropping a ball from the surface for opening and closing valve operations. Such operations are troublesome and time-consuming, the number of ball drops is limited, and the ball drops by gravity and cannot be used in highly deviated wells or horizontal well sections. Summary of the Invention

[0004] In order to overcome the problems in the prior art, the present invention provides a method and device for infinitely activating a downhole bypass system switch by pressure control.

[0005] The technical solution provided by the present invention to solve the above technical problems is: A pressure control infinitely activating downhole bypass system switch device, including an upper sub, a lower sub, a flow-through piston, a support spring, and a flow-through retaining ring. The flow-through piston has an upper cavity, a middle cavity, and a lower cavity that are sequentially connected. The diameter of the middle cavity is larger than that of the lower cavity;

[0006] The upper sub and the lower sub are connected to form a bypass housing; the flow-through piston is placed in the bypass housing through the support spring. The lower end of the flow control hammer is fixed to the lower sub through the flow-through retaining ring, and the upper end is placed in the lower cavity of the flow-through piston; the flow-through retaining ring is axially provided with a flow-through hole;

[0007] A positioning pin is radially provided on the inner wall of the upper sub and located within a commutation track;

[0008] On the outer wall of the upper end of the flow-through piston, there are a plugging track, a circulation track, and a commutation track. The plugging track and the circulation track are both communicated with the commutation track; a guiding system is provided in the commutation track. Through the guiding system, the positioning pin is controlled to move into the plugging track or the circulation track, so as to perform normal circulation drilling or plugging;

[0009] An overcurrent piston is provided with an open-valve cavity and a close-valve cavity, and an open-valve system and a close-valve system are respectively arranged in the open-valve cavity and the close-valve cavity; the open-valve system and the close-valve system respectively enable a guiding system to control the communication between a commutation track and a leak stoppage track or the communication between the commutation track and a circulation track; that is, the open-valve system and the close-valve system respectively enable the guiding system to control a positioning pin to move towards the leak stoppage track or the circulation track.

[0010] An overcurrent piston side through hole is provided on the overcurrent piston, and the overcurrent piston side through hole communicates with a lower cavity; an upper side through hole, a middle side through hole and a lower side through hole are further provided on the upper joint, and the lower side through hole is located below the overcurrent piston side through hole.

[0011] A further technical solution is that the guiding system includes a cam, a spring hinge and a guiding plate. The cam is connected to the guiding plate through the spring hinge and is installed on the outer wall of the overcurrent piston. The guiding plate is located in the commutation track, and the left and right movement of the guiding plate controls the communication between the commutation track and the leak stoppage track or the communication between the commutation track and the circulation track.

[0012] A further technical solution is that a cam right limiting groove and a cam left limiting groove are provided on the cam, and an elastic limiting pin is provided on the overcurrent piston. The elastic limiting pin is located in the cam right limiting groove.

[0013] A further technical solution is that the open-valve system includes an open-valve piston, an open-valve system moving ring, an open-valve needle, an open-valve system spring and an open-valve system positioning ring; the open-valve system moving ring is fixed in the middle of the open-valve needle. The upper end of the open-valve needle passes through the open-valve system positioning ring and is fixed on the lower end face of the open-valve piston. The open-valve system positioning ring is fixed on the inner wall of the open-valve cavity. The open-valve system spring is sleeved on the upper end of the open-valve needle and is located between the open-valve piston and the open-valve system positioning ring. The open-valve needle is located above the left end of the cam.

[0014] A further technical solution is that a communication cavity is provided inside the upper end of the upper joint. An open-valve system communication groove, an open-valve system communication hole and an open-valve system side through hole are provided on the overcurrent piston. The open-valve system communication groove, the open-valve system communication hole and the open-valve system side through hole are respectively communicated with the communication cavity and the open-valve cavity.

[0015] A further technical solution is that the close-valve system includes a close-valve piston, a close-valve system moving ring, a close-valve needle, a close-valve system spring and a close-valve system positioning ring; the close-valve system moving ring is fixed in the middle of the close-valve needle. The upper end of the close-valve needle passes through the close-valve system positioning ring and is fixed on the lower end face of the close-valve piston. The close-valve system positioning ring is fixed on the inner wall of the close-valve cavity. The close-valve system spring is sleeved on the upper end of the close-valve needle and is located between the close-valve piston and the close-valve system positioning ring. The close-valve needle is located above the right end of the cam.

[0016] A further technical solution is that a valve closing system communication groove, a valve closing system communication hole, and a valve closing system bypass hole are provided on the overcurrent piston, and the valve closing system communication groove, the valve closing system communication hole, and the valve closing system bypass hole are respectively communicated with the communication cavity and the valve closing cavity.

[0017] A further technical solution is that the cavity between the valve closing piston and the valve closing system positioning ring is the upper oil cavity of the valve closing system, the cavity between the valve closing system positioning ring and the valve closing system moving ring is the lower oil cavity of the valve closing system, and the valve closing system positioning ring is axially provided with a valve closing system seepage hole.

[0018] A further technical solution is that the cavity between the valve opening system positioning ring and the valve opening system moving ring is the lower oil cavity of the valve opening system, the cavity between the valve opening piston and the valve opening system positioning ring is the upper oil cavity of the valve opening system, and the valve opening system positioning ring is axially provided with a valve opening system seepage hole.

[0019] A method for infinitely activating a downhole bypass system switch by pressure control includes the following steps:

[0020] Step S10: Circulate and drill at normal displacement; when starting the pump, since the flow control hammer is in the lower cavity of the overcurrent piston and cannot flow normally, the valve opening system and the valve closing system are in the initial state; as the pump pressure increases, the overcurrent piston is pushed to move downward as a whole. At the same time, due to the action of the positioning pin, the overcurrent piston will rotate and move downward along the direction of the circulation track; until the flow control hammer completely enters the middle cavity of the overcurrent piston, a circulation channel is formed and normal drilling is carried out;

[0021] Among them, the supporting force of the supporting spring is calculated according to the following formula;

[0022] F = kx

[0023] In the formula: F is the supporting force when the spring is compressed; k is the spring compression system; x is the compression length of the spring;

[0024] Step S20: When plugging occurs, perform the following operations:

[0025] Step S201: Stop the pump; the system returns to the initial state;

[0026] Step S202: Start the pump until a certain designed pressure value is reached. The overcurrent piston moves downward as a whole until the middle bypass hole and the valve opening system bypass hole are communicated; at this time, the flow control hammer blocks the overcurrent in the lower cavity; the pressure difference between the inside and outside of the pipe acts on the valve opening piston of the valve opening system, and the upper oil cavity of the valve opening system of the valve opening system is compressed. The lubricating oil seeps downward through the valve opening system seepage hole to the lower oil cavity of the valve opening system, thereby realizing the downward movement of the valve opening needle; the guiding cam is dialed to turn to the right, thereby controlling the guiding plate to move to the left; at this time, the commutation preparation has been completed;

[0027] Step S203: Stop the pump. The flow-through piston moves upward and resets under the action of the support spring. The pressure on the valve-opening piston of the valve-opening system disappears. Under the action of the spring of the valve-opening system, the valve-opening piston moves upward, driving the valve-opening needle to move upward and restoring to the original state. After the positioning pin is reset through the guide plate, the guide plate remains in the left state under the action of the spring hinge.

[0028] Step S30: Pump in the plugging slurry. Under the pressure operation, the flow-through piston moves downward, and the positioning pin moves and guides into the plugging track. The side through-hole and the lower side through-hole of the flow-through piston are connected. At this time, the flow control hammer blocks the flow-through in the lower cavity. Then, the plugging operation is carried out. After the plugging slurry is pumped in, it enters the annulus through the side through-hole and the lower side through-hole of the flow-through piston.

[0029] Step S40: Stop the pump after the plugging operation is completed.

[0030] Step S50: Restore the guiding system to the initial state.

[0031] Step S501: Start the pump and build up the pressure to a certain designed pressure value. The whole flow-through piston moves downward until the upper side through-hole and the side through-hole of the valve-closing system are connected. At this time, the flow control hammer blocks the flow-through in the lower cavity. Under the pressure difference, the valve-closing piston of the valve-closing system moves downward, and the oil in the upper oil chamber of the valve-closing system enters the lower oil chamber of the valve-closing system through the seepage hole of the valve-closing system, so as to realize the downward movement of the valve-closing needle and drive the guiding cam to turn left, thereby controlling the guiding plate to move right.

[0032] Step S502: Stop the pump. The flow-through piston moves upward and resets under the action of the support spring. The pressure on the valve-closing piston of the valve-closing system disappears. Under the action of the spring of the valve-closing system, the piston of the valve-closing system moves upward, driving the valve-closing needle to move upward and restoring to the original state. The positioning pin is reset through the guide plate.

[0033] The present invention has the following beneficial effects: By simple ground pressure control, the present invention realizes the purpose of infinitely switching the bypass valve. Compared with the bypass valve that requires ball throwing for opening and closing the valve, it is more convenient and time-saving, and can be used in highly deviated wells or horizontal well sections. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0035] Figure 2 It is a schematic diagram of the valve-closing system of the present invention;

[0036] Figure 3 It is a schematic diagram of the valve-opening system of the present invention;

[0037] Figure 4 It is a schematic diagram of the valve-closing system of the present invention;

[0038] Figure 5 It is a schematic diagram of the positioning pin and the guiding system of the present invention.

[0039] As shown in the figure: 1 - upper joint; 2 - overcurrent piston; 3 - positioning pin; 4 - flow control hammer; 5 - support spring; 6 - overcurrent support ring; 7 - lower joint; 9 - valve opening system; 10 - middle side through hole; 11 - middle cavity; 12 - overcurrent piston side through hole; 13 - lower side through hole; 14 - lower cavity; 15 - overcurrent hole; 16 - valve closing system; 17 - upper side through hole; 18 - valve opening piston; 19 - valve opening system spring; 20 - valve opening system seepage hole; 21 - valve opening system positioning ring; 22 - valve opening system moving ring; 23 - valve opening needle; 24 - valve opening system communication groove; 25 - valve opening system upper oil cavity; 26 - communication cavity; 27 - valve opening system lower oil cavity; 28 - valve opening cavity; 29 - valve opening system communication hole; 30 - valve opening system side through hole; 31 - valve closing piston; 32 - valve closing system spring; 33 - valve closing system seepage hole; 34 - valve closing system positioning ring; 35 - valve closing system moving ring; 36 - valve closing needle; 37 - valve closing system communication groove; 38 - valve closing system upper oil cavity; 39 - valve closing system lower oil cavity; 40 - valve closing cavity; 41 - valve closing system communication hole; 42 - valve closing system side through hole; 43 - elastic limit pin; 44A - cam right limit groove; 44B - cam left limit groove; 45 - cam; 46 - leak plugging track; 47 - spring hinge; 48 - guide plate; 49 - circulation track. Detailed implementation manners

[0040] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0041] In the description of the present invention, it should be noted that, unless otherwise clearly defined and limited, the terms "installation" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection. 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 situations.

[0042] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "middle", "upper", "lower", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or part referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0043] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] As Figures 1-5 shown, a pressure-controlled infinitely activatable downhole bypass system switch device of the present invention includes an upper joint 1, a lower joint 7, an overcurrent piston 2, a support spring 5, and an overcurrent retaining ring 6. The overcurrent piston 2 has an upper cavity, a middle cavity 11, and a lower cavity 14 that are sequentially communicated. The diameter of the middle cavity 11 is larger than that of the lower cavity 14.

[0045] The upper joint 1 and the lower joint 7 are connected to form a bypass housing. The overcurrent piston 2 is placed in the bypass housing through the support spring 5. The lower end of the flow control hammer 4 is fixed to the lower joint 7 through the overcurrent retaining ring 6, and the upper end is placed in the lower cavity 14 of the overcurrent piston 2. The overcurrent retaining ring 6 is axially provided with an overcurrent hole 15. The flow control hammer 4 can block the fluid in the lower cavity 14.

[0046] On the outer wall of the upper end of the overcurrent piston 2, there are a plugging track 46, a circulation track 49, and a commutation track. The plugging track 46 and the circulation track 49 are both communicated with the commutation track. A guiding system is provided in the commutation track.

[0047] An open valve cavity 28 and a close valve cavity 40 are provided in the overcurrent piston 2. An open valve system 9 and a close valve system 16 are respectively provided in the open valve cavity 28 and the close valve cavity 40. The open valve system 9 and the close valve system 16 respectively enable the guiding system to control the communication between the commutation track and the plugging track 46 or the communication between the commutation track and the circulation track 49.

[0048] On the inner wall of the upper joint 1, a positioning pin 3 located in the commutation track is radially provided. An overcurrent piston bypass hole 12 is provided on the overcurrent piston 2. The overcurrent piston bypass hole 12 is communicated with the lower cavity 14. The upper joint 1 is also provided with an upper bypass hole 17, a middle bypass hole 10, and a lower bypass hole 13. The lower bypass hole 13 is located below the overcurrent piston bypass hole 12.

[0049] In this embodiment, the positioning pin 3 controls the rotation direction and movement position of the overcurrent piston 4, the flow control hammer 4 controls the flow direction of the drilling fluid, and the switch valve system 8 cooperates with the positioning pin 3 and the guiding system to control the opening and closing state of the bypass valve to achieve special operations and resume normal drilling circulation.

[0050] In this embodiment, the guiding system includes a cam 45, a spring hinge 47, and a guiding plate 48. The cam 45 is connected to the guiding plate 48 through the spring hinge 47 and is installed on the outer wall of the overcurrent piston 2. The guiding plate 48 is located in the commutation track, and its left and right movement controls the communication between the commutation track and the plugging track 46 or the communication between the commutation track and the circulation track 49.

[0051] In this embodiment, in order to prevent the cam 45 from rotating freely, a preferred embodiment is that the cam 45 is provided with a right cam limiting groove 44A and a left cam limiting groove 44B, and the flow-through piston 2 is provided with an elastic limiting pin 43. The elastic limiting pin 43 is located in the right cam limiting groove 44A or the left cam limiting groove 44B. In this way, when the cam 45 moves left or right, the elastic limiting pin 43 is located in the right cam limiting groove 44A or the left cam limiting groove 44B, and the elastic limiting pin 43 thus realizes the positioning of the cam 45.

[0052] As Figure 2 and 3 shown, a preferred embodiment of the valve opening system 9 in this embodiment is that the valve opening system 9 includes a valve opening piston 18, a valve opening system moving ring 22, a valve opening needle 23, a valve opening system spring 19, and a valve opening system positioning ring 21; the valve opening system moving ring 22 is fixed in the middle of the valve opening needle 23, the upper end of the valve opening needle 23 passes through the valve opening system positioning ring 21 and is fixed on the lower end surface of the valve opening piston 18, the valve opening system positioning ring 21 is fixed on the inner wall of the valve opening cavity 28, the valve opening system spring 19 is sleeved on the upper end of the valve opening needle 23 and is located between the valve opening piston 18 and the valve opening system positioning ring 21, the valve opening needle 23 is located above the left end of the cam 45, the upper joint 1 has a communication cavity 26 inside its upper end, the flow-through piston 2 is provided with a valve opening system communication groove 24, a valve opening system communication hole 29, and a valve opening system bypass hole 30. The valve opening system communication groove 24, the valve opening system communication hole 29, and the valve opening system bypass hole 30 are respectively communicated with the communication cavity 26 and the valve opening cavity 28. The cavity between the valve opening system positioning ring 21 and the valve opening system moving ring 22 is the lower oil cavity 27 of the valve opening system, and the cavity between the valve opening piston 18 and the valve opening system positioning ring 21 is the upper oil cavity 25 of the valve opening system. The valve opening system positioning ring 21 is axially provided with a valve opening system seepage hole 20.

[0053] As shown in FIGS. 2 and 4, in a preferred embodiment of the valve closing system 16 in this embodiment, the valve closing system 16 includes a valve closing piston 31, a valve closing system moving ring 35, a valve closing needle 36, a valve closing system spring 32, and a valve closing system positioning ring 34; the valve closing system moving ring 35 is fixed to the middle of the valve closing needle 36, the upper end of the valve closing needle 36 passes through the valve closing system positioning ring 34 and is fixed to the lower end face of the valve closing piston 31, the valve closing system positioning ring 34 is fixed to the inner wall of the valve closing cavity 40, the valve closing system spring 32 is sleeved on the upper end of the valve closing needle 36 and is located between the valve closing piston 31 and the valve closing system positioning ring 34, the valve closing needle 36 is located above the right end of the cam 45, the flow-through piston 2 is provided with a valve closing system communication groove 37, a valve closing system communication hole 41, and a valve closing system bypass hole 42, and the valve closing system communication groove 37, the valve closing system communication hole 41, and the valve closing system bypass hole 42 are respectively communicated with the communication cavity 26 and the valve closing cavity 40. The cavity between the valve closing piston 31 and the valve closing system positioning ring 34 is the upper oil cavity 38 of the valve closing system, the cavity between the valve closing system positioning ring 34 and the valve closing system moving ring 35 is the lower oil cavity 39 of the valve closing system, and the valve closing system positioning ring 34 is axially provided with a valve closing system seepage hole 33.

[0054] The upper bypass hole 17 and the middle bypass hole 10 are both located below the open valve system bypass hole 30 and the valve closing system bypass hole 42. At the same time, the upper bypass hole 17 is located above the middle bypass hole 10. Moreover, in the working process of this embodiment, during the downward movement of the flow-through piston 2, the open valve system bypass hole 30 will communicate with the middle bypass hole 10, and the valve closing system bypass hole 42 will communicate with the upper bypass hole 17.

[0055] The specific working process of this embodiment is as follows: The flow control hammer 4 is at different positions to achieve normal circulation and special operations such as plugging leaks.

[0056] During normal circulation, the flow-through piston 2 moves downward, and the flow control hammer 4 enters the middle cavity 11 of the flow-through piston 2 to form a circulation channel.

[0057] During normal circulation, the cam mechanism moves to the left and the guide plate 48 moves to the right; the positioning pin 3 moves in the circulation track 49 to control the rotation direction and movement position of the flow-through piston 2.

[0058] During normal circulation, the valve opening system communication hole 29 of the valve opening system 9 connects the communication cavity 26 and the valve opening system communication groove 24 to the valve opening cavity 28, so that the valve opening system 9 is in the original state; the valve closing system communication hole 41 of the valve closing system 16 connects the communication cavity 26 and the valve closing system communication groove 37 to the valve closing cavity 40, so that the valve closing system 16 is in the original state.

[0059] A method for infinitely activating a downhole bypass system switch by pressure control includes the following steps:

[0060] Step S10: Drilling in circulation at normal displacement; when starting the pump, since the flow control hammer 4 is in the lower chamber 14 of the flow-through piston, normal flow-through cannot occur, and the valve opening system 9 and the valve closing system 16 are in the initial state; as the pump pressure increases, the entire flow-through piston 4 is pushed downward, and at the same time, due to the action of the positioning pin 3, the flow-through piston 2 rotates and moves downward along the direction of the circulation track; until the flow control hammer 4 completely enters the middle chamber 11 of the flow-through piston, a circulation channel is formed, and normal drilling is carried out;

[0061] Among them, the supporting force of the supporting spring 5 is calculated according to the following formula;

[0062] F = kx

[0063] In the formula: F is the supporting force when the spring is compressed; k is the spring compression system; x is the compression length of the spring;

[0064] Step S20: When leakage occurs, perform the following operations:

[0065] Step S201: Stop the pump; the system returns to the initial state;

[0066] Step S202: Start the pump until a certain designed pressure value is reached, and the entire flow-through piston 2 moves downward until the middle side through hole 10 and the bypass through hole 30 of the valve opening system are connected; at this time, the flow control hammer 4 blocks the flow-through in the lower chamber 14; the pressure difference between the inside and outside of the pipe acts on the valve opening piston 18 of the valve opening system 9, and the upper oil chamber 25 of the valve opening system 9 is compressed, and the lubricating oil seeps downward through the seepage hole 20 of the valve opening system to the lower oil chamber 27 of the valve opening system, thereby realizing the downward movement of the valve opening needle 23; the guiding cam 45 is toggled to turn to the right, thereby controlling the guiding plate 48 to move to the left; at this time, the commutation preparation has been completed;

[0067] Step S203: Stop the pump, the flow-through piston 2 moves upward and resets under the action of the supporting spring 5, the pressure on the valve opening piston 18 of the valve opening system 9 disappears, and under the action of the valve opening system spring 19, the valve opening piston 18 moves upward, driving the valve opening needle 23 to move upward and restoring to the original state; after the positioning pin 3 is reset through the guiding plate 48, the guiding plate 48 remains in the left state under the action of the spring hinge 47;

[0068] Step S30: Pump in the plugging slurry; under pressure operation, the flow-through piston 2 moves downward, the positioning pin 3 moves and is guided into the plugging track 46, and the side through hole 12 of the flow-through piston and the lower side through hole 13 are connected; at this time, the flow control hammer 4 blocks the flow-through in the lower chamber 14; then, the plugging operation is carried out, and after the plugging slurry is pumped in, it enters the annulus through the side through hole 12 of the flow-through piston and the lower side through hole 13;

[0069] Step S40: Stop the pump after completing the plugging operation;

[0070] Step S50: Restore the guiding system to the initial state;

[0071] Step S501, start the pump, and pressurize to a certain design pressure value, the flow piston 2 moves downward as a whole, until the upper bypass hole 17 is connected with the bypass hole 42 of the valve closing system; at this time, the flow control hammer 4 blocks the flow in the lower cavity 14; under the action of the pressure difference, the valve closing piston 31 of the valve closing system 16 moves downward, and the oil in the upper oil chamber 38 of the valve closing system enters the lower oil chamber 39 of the valve closing system through the seepage hole 33 of the valve closing system, thereby realizing the downward movement of the valve closing needle 36, and the guide cam 45 is turned to the left, thereby controlling the guide plate 48 to move to the right;

[0072] Step S502, stop the pump, the flow piston 2 moves up and resets under the force of the support spring 5, the pressure on the valve closing piston 31 of the valve closing system 16 disappears, and under the action of the valve closing system spring 32, the valve closing system piston 31 moves upward, driving the valve closing needle 36 to move up and restore to the original state; the positioning pin 3 is reset through the guide plate 48.

[0073] The above description is not intended to impose any form of limitation on the present invention. Although the present invention has been disclosed through the above embodiments, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of the technical solution of the present invention.

Claims

1. A pressure-controlled infinitely activatable downhole bypass system switch device, characterized in that, It includes an upper joint (1), a lower joint (7), an overcurrent piston (2), a support spring (5), and an overcurrent retaining ring (6). The overcurrent piston (2) has an upper cavity, a middle cavity (11), and a lower cavity (14) that are sequentially connected. The diameter of the middle cavity (11) is larger than that of the lower cavity (14). The upper joint (1) and the lower joint (7) are connected to form a bypass housing. The overcurrent piston (2) is placed in the bypass housing through the support spring (5). The lower end of the flow control hammer (4) is fixed to the lower joint (7) through the overcurrent retaining ring (6), and the upper end is placed in the lower cavity (14) of the overcurrent piston (2). The overcurrent retaining ring (6) is axially provided with an overcurrent hole (15). On the outer wall of the upper end of the overcurrent piston (2), there are a leak stoppage track (46), a circulation track (49), and a commutation track. The leak stoppage track (46) and the circulation track (49) are both communicated with the commutation track. A guiding system is provided in the commutation track. An open valve cavity (28) and a closed valve cavity (40) are provided in the overcurrent piston (2). An open valve system (9) and a closed valve system (16) are respectively provided in the open valve cavity (28) and the closed valve cavity (40). The open valve system (9) and the closed valve system (16) respectively enable the guiding system to control the communication between the commutation track and the leak stoppage track (46) or the communication between the commutation track and the circulation track (49). A positioning pin (3) is radially provided on the inner wall of the upper joint (1). An overcurrent piston bypass hole (12) is provided on the overcurrent piston (2). The upper joint (1) is also provided with an upper bypass hole (17), a middle bypass hole (10), and a lower bypass hole (13). The lower bypass hole (13) is located below the overcurrent piston bypass hole (12). The overcurrent piston bypass hole (12) communicates with the lower bypass hole (13) of the housing during leak stoppage. The guiding system includes a cam (45), a spring hinge (47), and a guiding plate (48). The cam (45) is connected to the guiding plate (48) through the spring hinge (47) and is installed on the outer wall of the overcurrent piston (2). The guiding plate (48) is located in the commutation track, and its left and right movement controls the communication between the commutation track and the leak stoppage track (46) or the communication between the commutation track and the circulation track (49).

2. The pressure control infinitely actuated downhole bypass system switch device according to claim 1, characterized in that, The cam (45) is provided with a cam right limit groove (44A) and a cam left limit groove (44B). An elastic limit pin (43) is provided on the overcurrent piston (2). The elastic limit pin (43) is located in the cam right limit groove (44A) or the cam left limit groove (44B).

3. The pressure control infinitely actuated downhole bypass system switch device according to claim 2, wherein The valve opening system (9) includes a valve opening piston (18), a valve opening system moving ring (22), a valve opening needle (23), a valve opening system spring (19), and a valve opening system positioning ring (21); the valve opening system moving ring (22) is fixed in the middle of the valve opening needle (23), the upper end of the valve opening needle (23) passes through the valve opening system positioning ring (21) and is fixed on the lower end surface of the valve opening piston (18), the valve opening system positioning ring (21) is fixed on the inner wall of the valve opening cavity (28), the valve opening system spring (19) is sleeved on the upper end of the valve opening needle (23) and is located between the valve opening piston (18) and the valve opening system positioning ring (21), and the valve opening needle (23) is located at the left end of the cam (45).

4. A pressure control infinitely activatable downhole bypass system switch device according to claim 3, characterized in that, A communication cavity (26) is provided inside the upper end of the upper joint (1), and the flow-through piston (2) is provided with a valve opening system communication groove (24), a valve opening system communication hole (29), and a valve opening system bypass hole (30), and the valve opening system communication groove (24), the valve opening system communication hole (29), and the valve opening system bypass hole (30) are respectively communicated with the communication cavity (26) and the valve opening cavity (28).

5. A pressure control infinitely activatable downhole bypass system switch device according to claim 4, characterized in that, The valve closing system (16) includes a valve closing piston (31), a valve closing system moving ring (35), a valve closing needle (36), a valve closing system spring (32), and a valve closing system positioning ring (34); the valve closing system moving ring (35) is fixed in the middle of the valve closing needle (36), the upper end of the valve closing needle (36) passes through the valve closing system positioning ring (34) and is fixed on the lower end surface of the valve closing piston (31), the valve closing system positioning ring (34) is fixed on the inner wall of the valve closing cavity (40), the valve closing system spring (32) is sleeved on the upper end of the valve closing needle (36) and is located between the valve closing piston (31) and the valve closing system positioning ring (34), and the valve closing needle (36) is located at the right end of the cam (45).

6. A pressure control infinitely activatable downhole bypass system switch device according to claim 5, characterized in that, The flow-through piston (2) is provided with a valve closing system communication groove (37), a valve closing system communication hole (41), and a valve closing system bypass hole (42), and the valve closing system communication groove (37), the valve closing system communication hole (41), and the valve closing system bypass hole (42) are respectively communicated with the communication cavity (26) and the valve closing cavity (40).

7. The switch device of the pressure-controlled infinitely activatable downhole bypass system according to claim 6, wherein The cavity between the valve closing piston (31) and the valve closing system positioning ring (34) is the upper oil cavity (38) of the valve closing system, the cavity between the valve closing system positioning ring (34) and the valve closing system moving ring (35) is the lower oil cavity (39) of the valve closing system, and the valve closing system positioning ring (34) is axially provided with a valve closing system seepage hole (33).

8. A pressure control infinitely activatable downhole bypass system switch device according to claim 7, characterized in that, The cavity between the valve opening system positioning ring (21) and the valve opening system moving ring (22) is the lower oil cavity (27) of the valve opening system, the cavity between the valve opening piston (18) and the valve opening system positioning ring (21) is the upper oil cavity (25) of the valve opening system, and the valve opening system positioning ring (21) is axially provided with a valve opening system seepage hole (20).

9. A method for infinitely activating a downhole bypass system switch with pressure control, characterized in that, This method is carried out using a pressure-controlled infinitely activatable downhole bypass system switch device as described in claim 8, and includes the following steps: Step S10, drilling in a cycle according to normal displacement; when the pump is turned on, because the flow control hammer (4) is in the lower cavity (14), normal flow cannot flow through, and the valve opening system (9) and the valve closing system (16) are in the initial state; as the pump pressure increases, the support spring (5) is overcome to push the flow piston (2) downward as a whole; at the same time, due to the action of the positioning pin (3), the flow piston (2) will rotate downward along the circulation track direction; until the flow control hammer (4) completely enters the middle cavity (11), a circulation channel is formed, and drilling can proceed normally; The supporting force of the supporting spring (5) is calculated according to the following formula: F = kx In the formula: F is the supporting force when the spring is compressed; k is the spring compression system; x spring is the compressed length; Step S20: When leakage occurs, perform the following operations: Step S201, stop the pump; the system returns to the initial state; Step S202, start the pump to a certain design pressure value, the pressure difference on the upper part of the flow piston (2) overcomes the supporting force of the supporting spring (5) to push the flow piston (2) downward as a whole until the middle bypass hole (10) is connected to the bypass hole (30) of the valve opening system; at this time, the flow control hammer (4) blocks the flow in the lower cavity (14); the pressure difference inside and outside the tube acts on the valve opening piston (18) of the valve opening system (9), the valve opening system upper oil chamber (25) of the valve opening system (9) is compressed, and the lubricating oil seeps downward through the valve opening system seepage hole (20) to the valve opening system lower oil chamber (27), thereby realizing the downward movement of the valve opening needle (23); the cam (45) is turned to the right, thereby controlling the guide plate (48) to move to the left; at this time, the reversing preparation is completed; Step S203, stop the pump, the pressure difference of the flow piston (2) disappears, and the piston (2) moves upward and resets under the action of the support spring (5), and the pressure on the valve opening piston (18) of the valve opening system (9) disappears. Under the action of the valve opening system spring (19), the valve opening piston (18) moves upward, driving the valve opening needle (23) to move upward and restore to the original state; after the positioning pin (3) is reset by the guide plate (48), the guide plate (48) still maintains the left state under the action of the spring hinge (47); Step S30, pumping in the plugging slurry; under pressure operation, the flow piston (2) moves downward, the positioning pin (3) moves and guides into the plugging track (46), and the flow piston bypass hole (12) and the lower bypass hole (13) are connected; at this time, the flow control hammer (4) blocks the flow in the lower cavity (14); then the plugging operation is carried out, and the plugging slurry is pumped in and enters the annulus through the flow piston bypass hole (12) and the lower bypass hole (13); Step S40, stop the pump after completing the plugging operation; Step S50, restoring the guidance system to an initial state; Step S501, start the pump, and raise the pressure to a certain design pressure value. The flow piston (2) moves downward as a whole, and the positioning pin (3) moves and guides into the plugging track (46) until the upper bypass hole (17) and the valve closing system bypass hole (42) are connected; at this time, the flow control hammer (4) blocks the flow in the lower cavity (14); under the action of the pressure difference, the valve closing piston (31) of the valve closing system (16) moves downward, and the oil in the upper oil chamber (38) of the valve closing system enters the lower oil chamber (39) of the valve closing system through the valve closing system seepage hole (33), thereby realizing the downward movement of the valve closing needle (36), and the cam (45) is turned to the left, thereby controlling the guide plate (48) to move to the right; Step S502, stop the pump, the flow piston (2) moves up and resets under the action of the support spring (5), the pressure on the valve closing piston (31) of the valve closing system (16) disappears, and under the action of the valve closing system spring (32), the valve closing piston (31) moves upward, driving the valve closing needle (36) to move up and restore to the original state; the positioning pin (3) is reset through the guide plate (48).

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