Bypass circulation system capable of being opened and closed for infinite times and working method

Abstract

The invention provides an unlimited-time switch bypass circulation system and a working method, and the system comprises an upper short circuit, the upper short circuit and a lower short circuit are in threaded connection, an activation switch module is located in the upper short circuit, a time delay module is located in the activation switch module and the upper short circuit, and a pressure reversing module is located below the time delay module. The bypass sliding sleeve module is located below the pressure reversing module and located in the upper short circuit and the lower short circuit at the same time, and the lower piston module is located in the lower short circuit and the upper short circuit and located on the lower short circuit. When well leakage occurs in the drilling process or due to process requirements, high-concentration and large-particle leaking stoppage material and cement squeezing leaking stoppage construction can be carried out for infinite times without pulling out a hole, and construction such as circular well washing can be carried out.

Description

Technical Field

[0001] The present invention relates to the technical field of oil drilling, well repair and downhole operation, and in particular to a bypass circulation system capable of unlimited switching and opening and closing and a working method thereof. Background Art

[0002] When specialized operations are required during drilling and completion, such as plugging large leaks, each plugging operation requires pulling out the drill bit and replacing the plugging tool, often due to factors such as downhole instruments, screws, and water holes in the drill bit. This is time-consuming and labor-intensive. Furthermore, if the optimal timing for the operation is missed, downhole conditions become even more complex, severely impacting the plugging effectiveness. After the plugging operation is complete, the drill bit must be pulled out and replaced with normal drilling tools to resume drilling. This is particularly true in wells with multiple leaky zones, where frequent tripping and unplugging operations increase the risk of downhole complications, accidents, and poor well control.

[0003] With technological advancements, existing technologies have developed bypass valve tools that can open and close bypass circulation valves either once (e.g., patent CN112943157A) or multiple times (e.g., patent CN106401530B). In the event of a lost circulation, a ball can be dropped to open the bypass valve, allowing for prompt plugging. After plugging is complete, the drill is pulled to the wellhead, replaced with a new bypass valve, and then lowered back down to resume drilling.

[0004] The bypass valve tool can be opened and closed multiple times, typically 5-7 times. If more frequent openings and closings are required, the ball basket will need to be lengthened. A plugging ball is deployed to open the bypass valve and begin the plugging operation. After the plugging operation is complete, two valve-closing balls are deployed to close the two bypass holes, sealing the pressure chamber. By activating a pump on the surface and building up pressure, the plugging ball is sheared and dropped into the basket, along with the two valve-closing balls, allowing drilling to resume.

[0005] However, during field operations, special tools may be installed on the drill string, preventing the ball from being dropped from the drill string bore. Alternatively, due to excessive well deviation, the ball drop operation is very risky in directional and horizontal wells. Ball drop may not be properly positioned, and is therefore not recommended. This risk is increased if the drill string bore is not clean. Summary of the Invention

[0006] The present invention aims to address the shortcomings of the prior art by providing a bypass circulation system and operating method that can be opened and closed infinitely. This system does not require ball-dropping operations, but instead controls the displacement of fluid within the drill string to open and close the bypass hole. If lost circulation occurs during drilling, the system allows for unlimited application of high-concentration, large-particle plugging materials and cement squeezeouts, as well as circulation and well flushing operations, without starting the drill.

[0007] The present invention adopts the following technical solutions: A bypass circulation system that can be switched on and off infinitely includes an upper short circuit, which is connected to a lower short circuit by a threaded connection. An activation switch module is located inside the upper short circuit, a delay module is located inside the upper short circuit and below the activation switch module and above a pressure reversing module. The piston rod of the activation switch module is connected to a bypass sleeve module, the pressure reversing module is located below the delay module, the bypass sleeve module is located below the pressure reversing module, and a lower piston module is located inside the lower short circuit and sits on the lower short circuit.

[0008] The upper short-circuit includes an upper base, an upper pressure relief hole and an external bypass hole. The activation switch module includes an upper spring, a flow relief hole, a pressure transmission hole and an inner hole. One end of the upper spring abuts against the upper base, and the other end abuts against the upper shell of the activation switch module. The flow relief hole connects the inner hole and the upper spring. The pressure transmission hole connects the inner hole and the delay module. The delay module includes a piston rod, a piston, a closed inner cavity, a closed cylinder and a flow limiting hole. The piston rod and the piston are connected. The piston is installed in the closed inner cavity surrounded by the closed cylinder. The other end of the piston rod extends out of the flow limiting hole formed by the sealing cylinder and is connected to the bypass sleeve module. The pressure reversing module includes a one-way valve and a flow limiting piston. The one-way valve is connected to the flow limiting piston. The upper pressure relief hole connects the annulus and the pressure reversing module. The bypass sleeve module includes an inner bypass hole, an upper sleeve cavity, an elastic ferrule, a lower sleeve cavity, a reset spring and a limit block. The inner wall of the upper sleeve cavity is provided with an elastic ferrule, and the elastic ferrule includes a ferrule and an elastic block, and the ferrule is fixed on the elastic block. The lower sleeve cavity and the upper sleeve cavity are connected. One end of the reset spring abuts against the limit block, and the other end abuts against the upper shell of the bypass sleeve module. The lower piston module includes a mushroom head, a slot and a pressure spring. The mushroom head has a slot. One end of the pressure spring abuts against the mushroom head, and the other end is on the lower base. The lower short-circuit includes a spring chamber, a flow hole, a lower base and a lower pressure relief hole. The reset spring is located in the spring chamber. The flow hole connects the lower sleeve cavity and the lower short-circuit. The lower pressure relief hole connects the annulus and the interior of the lower short-circuit shell.

[0009] The bypass circulation system, which can be opened and closed infinitely, is installed in the annular well, with the upper drill string at the top and the lower drill string at the bottom.

[0010] A method for operating a bypass circulation system capable of unlimited switching, comprising the following steps: Connect the infinitely openable and closed bypass circulation system between the upper drill string and the lower drill string. The fluid flows through the inner cavity of the upper drill string, through the infinitely openable and closed bypass circulation system, and through the inner cavity of the lower drill string, and enters the annulus from the lower part of the lower drill string.

[0011] Under normal fluid circulation conditions, the fluid displacement is Q1. The fluid in the upper drill string pushes the activation switch module downward. Simultaneously, the fluid flows through the inner hole of the activation switch module, enters the bypass sleeve module, and then flows through the lower short-circuit flow hole to the lower drill string. Assume that the outer diameter of the upper end face of the activation switch module is D1, the inner hole diameter is D0, and the fluid density is Ruo. The elastic coefficient of the upper spring is K1. Using the formula for the pressure drop of flow in the pipe, the downward distance L1 of the activation switch module is calculated:

[0012] .

[0013] Furthermore, when a bypass cycle is required, the fluid displacement in the drill string is reduced to Q2. The upper pressure-upper hole of the activated switch module and the upper pressure-relief hole of the upper short circuit are on the same horizontal plane. The downward distance of the activated switch module is L2. Since the displacement Q2 is less than Q1, L2 is less than L1. Based on the known L2, the fluid displacement Q2 can be calculated: At this point, the fluid in the drill string pushes the pressure reversing module through the pressure-transmitting hole, causing the flow-limiting piston to move outward, closing the upper pressure relief hole. The fluid acts on the bypass sleeve module through the one-way valve, driving the piston rod of the delay module downward. Due to the delay module, the bypass sleeve module moves downward slowly. Set the delay time for the piston to pass through the flow-limiting hole to T.

[0014] After the delay time T expires, the bypass sleeve module rapidly descends, compressing the return spring and forcing the spring sleeve on the bypass sleeve module into the slot on the lower piston module. The bypass sleeve module and the lower piston module are now connected as one, isolating the upper and lower sleeve chambers, preventing fluid from flowing from the upper to the lower sleeve chamber.

[0015] Under the action of the fluid, the lower piston module drives the bypass sleeve downward, further compressing the return spring and the pressure spring on the lower piston module. This continues until the lower end of the bypass sleeve contacts the stop block, having traveled a distance L3. At this point, the inner and outer bypass holes are on the same level, allowing fluid to flow through the inner and outer bypass holes and into the annulus.

[0016] Furthermore, the delay time T is determined by the fluid density, the piston outer diameter D s and the inner diameter of the flow restriction hole d s The difference between the pressure inside the drill string and the annulus is determined by combining the pressure difference between the drill string and the annulus. m , the piston stroke is S, based on the fluid continuity equation and Bernoulli equation, ignoring the fluid friction, the bypass circulation system can be opened and closed infinitely at the displacement Q2. The pressure difference between the drill string and the annulus at the position is ΔP, and the delay time T can be calculated:

[0017] T Furthermore, when it is necessary to close the bypass circulation system that can be switched on and off infinitely, the fluid displacement is increased. At this time, the force F1 exerted by the fluid on the mushroom head of the lower piston module increases, and the force for the elastic sleeve to disengage from the slot on the mushroom head is set to F2. When F1>F2, the lower piston module continues to move downward, and the elastic sleeve disengages from the slot. The bypass sleeve module moves upward under the action of the reset spring, pushing the piston rod and piston above the sleeve module upward together, and the piston enters the closed inner cavity of the delay module. The bypass sleeve module is reset, and the delay module is reset. At this time, the fluid resumes flowing from the upper drill string, through the bypass circulation system that can be switched on and off infinitely, into the lower drill string, and then into the annulus.

[0018] Furthermore, by repeating the above steps, the bypass circulation system can be switched on and off an unlimited number of times.

[0019] Beneficial effects of the present invention: The present invention proposes a bypass circulation system that can be opened and closed infinitely. When leakage occurs during drilling or due to process requirements, high-concentration, large-particle plugging materials and cement squeezing plugging construction, as well as circulation and well washing construction can be carried out infinitely without starting drilling. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the internal structure of the present invention; Figure 2 It is a schematic diagram of the position layout in the wellbore of the present invention.

[0021] In the figure: 1- upper short circuit; 101-upper base, 102-upper pressure relief hole, 103-external bypass hole; 2- Activate the switch module; 201-upper spring, 202-drain hole, 203-pressure transmission hole, 204-inner hole; 3- Delay module; 301-piston rod, 3011-piston, 302-sealed inner cavity, 303-sealed cylinder, 304-flow limiting hole; 4-pressure reversing module; 401- one-way valve, 402- flow limiting piston; 5-Bypass sleeve module; 501-inner bypass hole, 502-sleeve upper cavity, 503-elastic ferrule, 5031-ferrule, 5032-elastic block, 504-sleeve lower cavity, 505-reset spring, 506-limit block; 6-lower piston module; 601-mushroom head, 602-slot, 603-pressure spring; 7- short circuit at the bottom; 701-spring chamber, 702-circulation hole, 703-lower base, 704-lower pressure relief hole; 100-unlimited switch bypass circulation system, 200-upper drill string, 300-lower drill string, 400-annulus. DETAILED DESCRIPTION

[0022] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention are described clearly and completely below. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0023] like Figure 1 As shown, the present invention provides an infinitely switchable bypass circulation system, comprising an upper short circuit 1, a lower short circuit 7, an activation switch module 2, a delay module 3, a pressure reversing module 4, a bypass sleeve module 5 and a lower piston module 6.

[0024] The upper shorting circuit 1 and the lower shorting circuit 7 are threadedly connected. The activation switch module 2 is located within the upper shorting circuit 1. The delay module 3 is located within the upper shorting circuit 1, below the activation switch module 2 and above the pressure reversing module 4. Its piston rod 301 is connected to the bypass sleeve module 5. The pressure reversing module 4 is located below the delay module 3. The bypass sleeve module 5 is located below the pressure reversing module 4. The lower piston module 6 is located within the lower shorting circuit 7 and sits on it.

[0025] like Figure 1As shown, the upper short circuit 1 includes an upper base 101, an upper pressure relief hole 102 and an external bypass hole 103. The activation switch module 2 includes an upper spring 201, a leakage hole 202, a pressure transmission hole 203 and an inner hole 204. One end of the upper spring 201 abuts against the upper base 101, and the other end abuts against the upper shell of the activation switch module 2. The leakage hole 202 connects the inner hole 204 and the upper spring 201. The pressure transmission hole 203 connects the inner hole 204 and the delay module 3. The delay module 3 includes a piston rod 301, a piston 3011, a closed inner cavity 302, a closed cylinder 303 and a flow limiting hole 304. The piston rod 301 and the piston 3011 are connected. The piston 3011 is installed in the closed inner cavity 302 surrounded by the closed cylinder 303. The other end of the piston rod 301 extends out of the flow limiting hole 304 formed by the sealing cylinder 303 and is connected to the bypass sleeve module 5. The pressure reversing module 4 includes a one-way valve 401 and a flow-limiting piston 402, the one-way valve 401 being connected to the flow-limiting piston 402. The upper pressure relief hole 102 connects the annulus 400 with the pressure reversing module 4. The bypass sleeve module 5 includes an inner bypass hole 501, an upper sleeve chamber 502, an elastic sleeve 503, a lower sleeve chamber 504, a return spring 505, and a stop block 506. The inner wall of the upper sleeve chamber 502 is provided with an elastic sleeve 503, which includes a sleeve 5031 and an elastic block 5032. The sleeve 5031 is fixed to the elastic block 5032. The lower sleeve chamber 504 is connected to the upper sleeve chamber 502. One end of the return spring 505 abuts against the stop block 506, and the other end abuts against the upper housing of the bypass sleeve module 5. The lower piston module 6 includes a mushroom head 601, a slot 602, and a pressure spring 603. The mushroom head 601 has a slot 602. One end of the pressure spring 603 abuts against the mushroom head 601, and the other end rests on the lower base 703. The lower short-circuit 7 includes a spring chamber 701, a flow hole 702, a lower base 703, and a lower pressure relief hole 704. The return spring 505 is located in the spring chamber 701. The flow hole 702 connects the lower sleeve chamber 504 and the lower short-circuit 7. The lower pressure relief hole 704 connects the annulus 400 and the interior of the lower short-circuit 7 housing.

[0026] Furthermore, the outer diameter of the piston 3011 is slightly smaller than the inner diameter of the flow limiting hole 304 on the sealing cylinder 303 .

[0027] like Figure 2 As shown, the above-mentioned bypass circulation system 100 capable of unlimited opening and closing has an upper drill string 200 at its upper portion and a lower drill string 300 at its lower portion.

[0028] The present invention provides a method for operating a bypass circulation system capable of unlimited switching, comprising the following steps: Step 1. Connect the bypass circulation system 100 that can be opened and closed infinitely between the upper drill string 200 and the lower drill string 300. The fluid flows through the inner cavity of the upper drill string 200, the bypass circulation system 100 that can be opened and closed infinitely, and the inner cavity of the lower drill string 300, and enters the annulus 400 from the lower part of the lower drill string 300.

[0029] Step 2. Under normal fluid circulation conditions, with a fluid displacement of Q1, the fluid in upper drill string 200 pushes the activation switch module 2 downward. Simultaneously, the fluid flows through inner hole 204 of activation switch module 2, enters bypass sleeve module 5, and flows through flow hole 702 of lower short circuit 7, before entering lower drill string 300. Assume that the outer diameter of the upper end face of activation switch module 2 is D1, the inner hole diameter is D0, and the fluid density is Ruo. The elastic coefficient of upper spring 201 is K1. The downward distance L1 of activation switch module 2 can be calculated using the formula for in-pipe pressure drop:

[0030] (Formula 1) Step 3. When a bypass cycle is needed, reduce the fluid displacement in the drill string to Q2. Activate the upper pressure-upper hole 203 of the switch module 2 and the upper pressure-relief hole 102 on the upper short-circuit 1 at the same level. The downward distance of the activated switch module 2 is L2. Since the displacement Q2 is less than Q1, L2 is less than L1. Based on the known L2, the fluid displacement Q2 can be calculated: (Formula 2) At this time, the fluid in the drill string pushes the pressure reversing module 4 outward through the pressure transmission hole 203, and the flow limiting piston 402 moves outward together, closing the upper pressure relief hole 102. At this time, the fluid pressure acts on the bypass sleeve module 5, driving the piston rod 301 of the delay module 3 downward. Due to the action of the delay module 3, the bypass sleeve module 5 moves downward slowly. The delay time for the piston 3011 to pass through the flow limiting hole 304 is set to T, which is determined by the fluid density and the piston outer diameter D. s and the inner diameter of the flow restriction hole d s The difference between the drill string and the annulus 400 is determined by the combination of the pressure difference. Set the inner diameter of the sealing tube to d m , the piston stroke is S, based on the fluid continuity equation and Bernoulli equation, ignoring the fluid friction, the bypass circulation system can be opened and closed infinitely at the displacement Q2. The pressure difference between the drill string and the annulus at the position is △P, and the delay time T can be calculated:

[0031] T (Formula 3) After the delay time T is reached, the bypass sleeve module 5 rapidly descends, the return spring 505 is compressed, and the elastic sleeve 503 on the bypass sleeve module 5 enters the retaining groove 602 on the lower piston module 6. At this point, the bypass sleeve module 5 and the lower piston module 6 are connected as one, and the upper sleeve chamber 502 and the lower sleeve chamber 504 are isolated. Fluid cannot flow from the upper sleeve chamber 502 to the lower sleeve chamber 504, and the bypass circulation system 100 can be activated and closed an unlimited number of times.

[0032] Step 4. Under the action of the fluid, the lower piston module 6 drives the bypass sleeve slider 5 downward, further compressing the return spring 505 and the pressure spring 603 on the lower piston module 6. The bypass sleeve module 5 moves downward a distance L3 until its lower end contacts the stop block 506. At this point, the inner bypass hole 501 and the outer bypass hole 103 are on the same horizontal plane, allowing the fluid to enter the annulus 400 through the inner and outer bypass holes 501 and 103. The bypass circulation system 100 can be opened and closed indefinitely, maintaining the bypass circulation operating state.

[0033] Step 5. When the bypass circulation system 100 with unlimited opening and closing needs to be closed, the fluid displacement is increased. At this time, the force F1 exerted by the fluid on the mushroom head 601 of the lower piston module 6 increases, and the force for the elastic sleeve 503 to disengage from the groove 602 on the mushroom head 601 is set to F2. When F1>F2, the lower piston module 6 continues to descend, and the elastic sleeve 503 disengages from the groove 602. The bypass sleeve module 5 moves upward under the action of the return spring 505, driving the piston rod 301 into the sealed inner chamber 302, and the bypass sleeve module 5 is reset. The bypass circulation system 100 with unlimited opening and closing is closed. At this time, the fluid resumes flowing from the upper drill string 200, through the bypass circulation system 100 with unlimited opening and closing, into the lower drill string 300, and then into the annulus 400.

[0034] Repeating steps 1 to 5 can realize the unlimited switching of the bypass circulation system 100.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A bypass circulation system capable of unlimited switching, characterized in that: It includes an upper short circuit, which is connected to the lower short circuit by threads. The activation switch module is located inside the upper short circuit, the delay module is located inside the upper short circuit and below the activation switch module and above the pressure reversing module. The piston rod of the activation switch module is connected to the bypass sleeve module, the pressure reversing module is located below the delay module, the bypass sleeve module is located below the pressure reversing module, and the lower piston module is located inside the lower short circuit and sits on the lower short circuit.

2. The system according to claim 1, wherein: The upper short circuit includes an upper base, an upper pressure relief hole and an external bypass hole. The activation switch module includes an upper spring, a discharge hole, a pressure transmission hole and an inner hole. One end of the upper spring abuts against the upper base, and the other end abuts against the upper shell of the activation switch module. The discharge hole connects the inner hole and the upper spring, and the pressure transmission hole connects the inner hole and the delay module. The delay module includes a piston rod, a piston, a closed inner cavity, a closed cylinder and a flow limiting hole. The piston rod is connected to the piston, and the piston is installed in the closed inner cavity surrounded by the closed cylinder. The other end of the piston rod extends out of the flow limiting hole formed by the sealing cylinder and is connected to the bypass sleeve module. The pressure reversing module includes a one-way valve and a flow limiting piston. The one-way valve is connected to the flow limiting piston. The upper pressure relief hole connects the annulus and the pressure reversing module. The bypass sleeve module includes an inner bypass hole, an upper sleeve cavity, an elastic sleeve, a lower sleeve cavity, a return spring and a limit block. The inner wall of the upper sleeve cavity is provided with an elastic sleeve. The elastic sleeve includes a sleeve and an elastic block. The sleeve is fixed on the elastic block. The lower sleeve cavity and the upper sleeve cavity are connected. One end of the return spring abuts the limit block and the other end abuts on the upper shell of the bypass sleeve module. The lower piston module includes a mushroom head, a slot and a pressure spring. The mushroom head is provided with a slot. One end of the pressure spring abuts on the mushroom head and the other end is on the lower base. The lower short-circuit includes a spring chamber, a flow hole, a lower base and a lower pressure relief hole. The return spring is located in the spring chamber, the flow hole connects the lower sleeve cavity and the lower short-circuit, and the lower pressure relief hole connects the annulus and the inside of the lower short-circuit shell.

3. A method for operating a bypass circulation system capable of unlimited opening and closing, comprising connecting the bypass circulation system capable of unlimited opening and closing between an upper drill string and a lower drill string, wherein fluid flows through the inner cavity of the upper drill string, through the bypass circulation system capable of unlimited opening and closing, and through the inner cavity of the lower drill string, and into the annulus from the lower portion of the lower drill string, characterized in that: When the fluid is circulating normally, the fluid displacement is Q1. The fluid in the upper drill string pushes the activation switch module downward. At the same time, the fluid flows through the inner hole of the activation switch module, enters the bypass sleeve module, and the flow hole of the lower short circuit to enter the lower drill string. The outer diameter of the upper end face of the activation switch module is set to D1, the inner hole diameter is D0, the fluid density is Ruo, and the elastic coefficient of the upper spring is K1. The downward distance L1 of the activation switch module is calculated using the pressure drop formula for in-pipe flow: 。 4. The method according to claim 3, characterized in that Also includes: When a bypass cycle is required, the fluid displacement in the drill string is reduced to Q2. The upper pressure-upper hole of the activated switch module and the upper pressure-relief hole of the upper short circuit are on the same horizontal plane. The downward distance of the activated switch module is L2. Since the displacement Q2 is less than Q1, L2 is less than L1. Based on the known L2, the fluid displacement Q2 is calculated as follows: At this time, the fluid in the drill string pushes the pressure reversing module outward through the pressure transmission hole, causing the flow-limiting piston to move outward together, closing the upper pressure relief hole. The fluid acts on the bypass sleeve module through the one-way valve, driving the piston rod of the delay module downward. Due to the action of the delay module, the bypass sleeve module moves downward slowly. The delay time for the piston to pass through the flow-limiting hole is set to T; After the delay time T is reached, the bypass sleeve module moves downward rapidly, the return spring is compressed, and the elastic sleeve on the bypass sleeve module enters the slot on the lower piston module. At this time, the bypass sleeve module and the lower piston module are connected as one, and the upper and lower sleeve chambers are isolated, so that the fluid cannot flow from the upper sleeve chamber to the lower sleeve chamber. Under the action of the fluid, the lower piston module drives the bypass sleeve slider downward, the return spring continues to be compressed, and the pressure spring on the lower piston module is compressed at the same time until the lower end of the bypass sleeve module contacts the limit block. The downward distance is L3. At this time, the inner bypass hole and the outer bypass hole are on the same horizontal plane, and the fluid enters the annulus through the inner bypass hole and the outer bypass hole.

5. The method according to claim 4, characterized in that The delay time T is determined by the fluid density, piston outer diameter D s and the inner diameter of the flow restriction hole d s The difference between the pressure inside the drill string and the annulus is determined by combining the pressure difference between the drill string and the annulus, and the inner diameter of the sealing tube is set to d m , the piston stroke is S, based on the fluid continuity equation and Bernoulli equation, ignoring the fluid friction, the bypass circulation system can be opened and closed infinitely at the displacement Q2. The pressure difference between the drill string and the annulus at the position is △P, and the delay time T is calculated: 。 6. The method according to claim 4 or 5, characterized in that When it is necessary to close the bypass circulation system that can be opened and closed infinitely, the fluid displacement is increased. At this time, the force F1 of the fluid acting on the mushroom head of the lower piston module increases, and the force for the elastic sleeve to disengage from the groove on the mushroom head is set to F2. When F1>F2, the lower piston module continues to descend, the elastic sleeve is disengaged from the groove, and the bypass sleeve module moves upward under the action of the reset spring, driving the piston rod into the closed inner cavity, and the bypass sleeve module is reset. At this time, the fluid resumes flowing from the upper drill string, through the bypass circulation system that can be opened and closed infinitely, into the lower drill string, and then into the annulus state.

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