Tool and method for monitoring bit bouncing and jamming

Abstract

The invention relates to a drill bit bouncing and jamming monitoring tool and a detection method, which are mainly used for dynamically regulating and controlling the torque of a drill bit and monitoring serious bouncing or jamming of the drill bit in the drilling process of an oil and gas field. The tool comprises a friction clutch part and a bit bouncing and jamming monitoring part which are combined through threaded connection. In the working process, the threaded mandrel of the bit bouncing monitoring part can stretch out and draw back along with the change of the reaction torque on the drill bit, so that the violent fluctuation of the torque is inhibited, and the dynamic regulation and control of the torque are realized. When bit bouncing or jamming happens to the drill bit, the torque clutch part of the tool can interrupt the torque of the drill column and the drill bit, the ground can monitor reduction of the torque of the drill column, and bit bouncing or jamming of the drill bit is recognized. According to the technical scheme, bit bouncing and jamming of the drill bit can be monitored, and safety and operation efficiency of deep well drilling are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas field development, and particularly to a monitoring tool and detection method for bit sticking and pipe sticking during drilling. Background Art

[0002] As important strategic resources, oil and gas resources play a crucial role in human economic development, industrial production, national defense and military, and daily life. During the development of oil and gas resources, the drilling stage is one of the stages with the highest cost, risk, and technical difficulty. During the drilling process, when drilling through the interlaced area of formations with different hardnesses, the bit is relatively easy to drill in soft formations, but it will encounter greater resistance when encountering hard formations. This sudden change in resistance will cause vibration and sticking of the bit and drill string, or pipe sticking due to formation collapse, shrinkage, etc. In severe cases, the bit will be stuck. Since the ground cannot timely monitor bit sticking or pipe sticking, the torque will continuously increase, resulting in the accident of drill string breakage, seriously affecting the safety and efficiency of drilling.

[0003] In the existing drill string vibration monitoring technologies, including surface measurement systems and downhole measurement-while-drilling systems, due to the large flexibility of the drill string and its frequent contact with the wellbore, surface measurement cannot accurately judge the lateral vibration of the downhole drill string, and most surface measurements have a low sampling frequency, resulting in limited monitoring effects for some complex downhole vibration conditions. Real-time downhole measurement-while-drilling is limited by the transmission speed of mud pulse signals and has a low sampling frequency, unable to meet the needs of more in-depth research such as subsequent spectral analysis of signals. The storage measurement method cannot provide real-time feedback on downhole vibration, bit sticking, and pipe sticking during drilling.

[0004] In order to solve the problems of regulating drill string vibration, monitoring bit sticking and pipe sticking, and protecting the drill string to improve drilling safety during the drilling process, it is urgent to invent a monitoring tool and identification method for bit sticking and pipe sticking during drilling. Summary of the Invention

[0005] The object of the present invention is to provide a monitoring tool and identification method for bit sticking and pipe sticking, which can effectively reduce bit vibration. When bit sticking or pipe sticking occurs, it can technically cut off torque transmission, reduce the torque of the drill string, prevent drill string breakage, and enable the ground to immediately discover bit sticking and pipe sticking according to the bit sticking and pipe sticking identification method and take corresponding measures. A monitoring tool for bit sticking and pipe sticking is a pure mechanical structure and can work in high-temperature and high-pressure environments.

[0006] The technical solution adopted by the present invention to solve its technical problems is as follows:

[0007] A sticking and jamming monitoring tool for a drill bit, comprising a torque clutch mechanism and a sticking and jamming monitoring mechanism;

[0008] The torque clutch mechanism includes an upper sub, an upper seal housing, an upper seal ring, a bearing housing, a thrust series bearing, a bearing inner ring fixing nut, a spline housing, an inner friction plate, an outer friction plate, a pressure plate, a push rod, a piston, a piston seal ring, a piston spring, a seal nut sleeve, a connecting housing, and a check valve.

[0009] The outer diameter of the upper sub gradually decreases in steps from top to bottom, and is successively described as shaft section Ⅰ, shaft section Ⅱ, shaft section Ⅲ, shaft section Ⅳ, and shaft section Ⅴ;

[0010] Threaded female threads are provided on shaft section Ⅰ for connecting the upper drill string;

[0011] The upper seal ring is installed in the seal groove of the upper seal housing. The upper seal housing is sleeved on the upper sub, and the upper seal ring forms a seal with the surface of shaft end Ⅱ of the upper sub. The inner ring of the thrust series bearing is sleeved on shaft section Ⅲ of the upper sub and is positioned and fixed by the bearing inner ring fixing nut. The outer ring of the thrust series bearing is sleeved in the bearing housing, and the thrust series bearing is positioned and fixed by the threaded connection between the upper seal housing and the bearing housing. The upper sub and the bearing housing can rotate relative to each other freely;

[0012] A spline housing is sleeved on shaft section Ⅳ of the upper sub. The spline housing is provided with a boss in the middle, dividing the inner cavity into upper and lower parts. The inner hole of the upper part is provided with internal splines, and the outer friction plate meshes with the internal splines of the spline housing through external splines; the inner hole wall of the lower part is smooth for installing the piston; external splines are provided on shaft section Ⅳ of the upper sub, and the inner friction plate meshes with the external splines of shaft section Ⅳ of the upper sub through internal splines; the inner friction plate and the outer friction plate are installed alternately to form a friction plate, and a pressure plate and a push rod are provided below; the push rod passes through the through hole on the boss of the spline housing, and the two ends of the push rod are respectively connected to the pressure plate and the piston; the upper and lower ends of the spline housing are respectively connected to the bearing housing and the connecting housing by threads, and the friction plate transmits the torque of the upper sub to the spline housing through friction.

[0013] The piston is provided with a seal groove, and a piston seal ring is installed in the seal groove. The piston divides the smooth lower part of the inner wall of the spline housing into two chambers. The upper hydraulic chamber is connected to the wellbore annulus through the first opening on the boss of the spline housing, and the lower hydraulic chamber is connected to the drilling fluid flow channel of the upper sub through the second opening on shaft section Ⅴ of the upper sub; the piston spring is installed in the upper hydraulic chamber and provides a downward thrust to move the piston downward in the working state of disconnecting torque transmission.

[0014] The check valve is installed on the connecting housing;

[0015] The seal nut sleeve is installed on shaft section Ⅴ of the upper sub by threads.

[0016] The sticking and jamming monitoring mechanism includes a disc spring housing, a central pipe, disc springs, a falling prevention pipe, a sealing ring, a threaded housing, a threaded shaft, a lower sealing housing, and a lower sealing ring.

[0017] The upper end of the disc spring housing is connected to the connecting housing by a thread, the lower end is connected to the threaded housing by a thread, and the lower end of the threaded housing is connected to the lower sealing housing by a thread; a lower sealing ring is installed inside the lower sealing housing;

[0018] A central pipe is provided inside the disc spring housing, and a threaded shaft is provided inside the threaded housing; the central pipe and the threaded shaft are connected by a falling prevention pipe;

[0019] The central pipe includes an upper pipe string and a lower pipe string. Disc springs are installed in the annular space formed by the upper pipe string and the disc spring housing; a central opening is provided on the lower pipe string, and two sealing rings are installed in the annular space formed by the lower pipe string and the disc spring housing, and the two sealing rings are distributed on the upper and lower sides of the central opening.

[0020] An annular groove is provided on the upper pipe string of the central pipe for connecting the lower hydraulic chamber and the annulus when torque transmission is disconnected. A sealing ring is installed on the upper end of the central pipe for sealing the second opening of the lower hydraulic chamber and the internal flow path of the upper joint when torque transmission is disconnected.

[0021] In the working state of disconnecting torque transmission, the lower hydraulic chamber of the piston will be connected to the check valve through the annular groove of the central pipe, the check valve is connected to the annulus, and the check valve allows the drilling fluid to only flow from the lower hydraulic chamber to the annulus, and the annulus drilling fluid cannot flow into the lower hydraulic chamber.

[0022] In the working state where the torque clutch mechanism is in torque engagement, the drilling fluid in the wellbore annulus enters the upper hydraulic chamber of the piston through the first opening on the boss of the spline housing, the drilling fluid in the central pipe enters the lower hydraulic chamber of the piston through the opening of the fifth section of the upper joint shaft. The sticking and jamming monitoring tool is installed above the positive displacement motor. The internal drilling fluid pressure of the tool is higher than the annulus pressure. The liquid pressure in the lower hydraulic chamber of the piston is higher than the upper hydraulic chamber, and the piston generates an upward thrust, which is transmitted to the friction disc pressing plate through the push rod, and the friction disc pressing plate presses the friction discs against each other to achieve torque transmission. When the central pipe moves to the uppermost position, the sealing nut sleeve forms a seal with the sealing ring at the upper end of the central pipe to block the second opening on the fifth section of the upper joint shaft.

[0023] In the working state where the torque clutch mechanism is in torque engagement and the central pipe moves to the uppermost position, the lower hydraulic chamber of the piston will be connected to the check valve through the annular groove of the central pipe, the check valve is connected to the annulus, and the check valve allows the drilling fluid to only flow from the lower hydraulic chamber to the annulus, and the annulus drilling fluid cannot flow into the lower hydraulic chamber.

[0024] The multi-disc friction plates adopted by the torque clutch mechanism transmit torque. The pressing force between the friction plates comes from the hydraulic pressure acting on the piston, and the engagement and disengagement of the torque clutch are controlled by the position of the central tube.

[0025] The central tube moves up and down along the threaded shaft. When the central tube moves to the uppermost position, it changes the flow path of the drilling fluid in the hydraulic chamber under the piston. The drilling fluid in the hydraulic chamber under the piston changes from being connected to the drilling fluid inside the upper sub to being connected to the annulus drilling fluid, and the torque clutch realizes torque disengagement. When the central tube is in other positions, the torque clutch mechanism realizes torque engagement.

[0026] A method for monitoring the sticking and jamming of a drill bit, specifically, during normal drilling, by monitoring the torque of the drill string, the torque fluctuates within a certain range, and the fluctuation amplitude is smaller than that without using the tool for monitoring the sticking and jamming of the drill bit. When the ground monitors that the torque of the drill string increases and suddenly becomes smaller after increasing to the limit torque set by the tool, and the limit torque set by the tool is less than the ultimate strength of the drill string, it indicates that there is a sticking or jamming phenomenon downhole. Slowly lift the drill string. If the drill string can be lifted, it indicates a sticking, and if the drill string cannot be lifted, it indicates a jamming. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0028] Figure 1 It is a sectional view of the whole of the present invention:

[0029] Figure 2 It is a schematic diagram of the structure of the upper sub of the present invention:

[0030] Figure 3 It is a schematic diagram of the structure of the spline housing of the present invention:

[0031] Figure 4 It is a schematic diagram of the structure of the central tube of the present invention:

[0032] Figure 5 It is a schematic diagram of the central tube and the piston in the initial state of the present invention:

[0033] Figure 6 It is a schematic diagram of the central tube and the piston in the state where the torque transmission is disconnected of the present invention.

[0034] In the figure: 1 - upper joint, 2 - upper sealing ring, 3 - upper sealing shell, 4 - thrust series bearing, 5 - bearing housing, 6 - bearing inner ring fixing nut, 7 - inner disc of friction plate, 8 - outer disc of friction plate, 9 - pressure plate, 10 - push rod, 11 - spline housing, 12 - piston spring, 13 - piston, 14 - piston sealing ring, 15 - sealing nut sleeve, 16 - sealing ring, 17 - connecting housing, 18 - check valve, 19 - disc spring, 20 - disc spring housing, 21 - central tube, 22 - sealing ring, 23 - anti - dropping tube, 24 - threaded housing, 25 - threaded shaft, 26 - lower sealing shell, 27 - lower sealing ring. Specific embodiments

[0035] The following further describes the invention in conjunction with the accompanying drawings. The protection scope of the present invention is not limited to the following description:

[0036] As Figures 1-6 shown, a sticking and jamming monitoring tool for a drill bit includes a torque clutch mechanism and a sticking and jamming monitoring mechanism; the torque clutch mechanism includes an upper joint 1, an upper sealing shell 3, an upper sealing ring 2, a bearing housing 5, a thrust series bearing 4, a bearing inner ring fixing nut 6, a spline housing 11, an inner disc of friction plate 7, an outer disc of friction plate 8, a pressure plate 9, a push rod 10, a piston 13, a piston sealing ring 14, a piston spring 12, a sealing nut sleeve 15, a connecting housing 17, and a check valve 18.

[0037] The outer diameter of the upper joint 1 gradually decreases in steps from top to bottom, and is successively described as shaft section Ⅰ, shaft section Ⅱ, shaft section Ⅲ, shaft section Ⅳ, and shaft section Ⅴ;

[0038] Shaft section Ⅰ is provided with a threaded female thread for connecting the upper drill string;

[0039] The upper sealing ring 2 is installed in the sealing groove of the upper sealing shell 3. The upper sealing shell 3 is sleeved on the upper joint 1, and the upper sealing ring 2 forms a seal with the surface of the shaft end Ⅱ of the upper joint 1. The inner ring of the thrust series bearing 4 is sleeved on the shaft section Ⅲ of the upper joint 1 and is positioned and fixed by the bearing inner ring fixing nut 6. The outer ring of the thrust series bearing 4 is sleeved in the bearing housing 5, and the thrust series bearing 4 is positioned and fixed by the threaded connection between the upper sealing shell 3 and the bearing housing 5. The upper joint 1 and the bearing housing 5 can rotate relative to each other freely;

[0040] A spline housing 11 is sleeved on the shaft section Ⅳ of the upper sub 1. A boss is provided in the middle of the spline housing 11, dividing the inner cavity into upper and lower parts. An internal spline 1102 is provided in the inner hole of the upper part. The outer disc 8 of the friction plate is engaged with the internal spline 1102 of the spline housing 11 through an external spline; the inner wall of the lower part of the inner hole is smooth for installing the piston 13; an external spline is provided on the shaft section Ⅳ of the upper sub 1. The inner disc 7 of the friction plate is engaged with the external spline on the shaft section Ⅳ of the upper sub 1 through the internal spline 1102; the inner disc 7 and the outer disc 8 of the friction plate are installed alternately to form a friction plate, and a pressure plate 9 and a push rod 10 are provided below; the push rod 10 passes through the through hole 1103 on the boss of the spline housing 11, and both ends of the push rod 10 are respectively connected to the pressure plate 9 and the piston 13; the upper and lower ends of the spline housing 11 are respectively connected to the bearing housing 5 and the connection housing 17 through threads, and the friction plate transfers the torque of the upper sub 1 to the spline housing 11 through friction.

[0041] The piston 13 is provided with a sealing groove, and a piston seal ring 14 is provided in the sealing groove. The piston 13 divides the smooth lower part of the inner wall of the spline housing 11 into two chambers. The upper hydraulic chamber is communicated with the wellbore annulus through the first opening 1101 on the boss of the spline housing 11, and the lower hydraulic chamber is communicated with the drilling fluid flow channel of the upper sub 1 through the second opening 102 on the shaft section Ⅴ of the upper sub 1; the piston spring 12 is installed in the upper hydraulic chamber to provide a downward thrust to move the piston downward in the working state of disconnecting torque transmission.

[0042] A check valve 18 is installed on the connection housing 17;

[0043] The sealing nut sleeve 15 is installed on the shaft section Ⅴ of the upper sub 1 through threads.

[0044] The sticking and jamming monitoring mechanism includes a disc spring housing 20, a central tube 21, a disc spring 19, a falling prevention tube 23, a sealing ring 22, a threaded housing 24, a threaded shaft 25, a lower sealing housing 26, and a lower sealing ring 27.

[0045] The upper end of the disc spring housing 20 is connected to the connection housing 17 through a thread, and the lower end is connected to the threaded housing 24 through a thread. The lower end of the threaded housing 24 is connected to the lower sealing housing 26 through a thread; a lower sealing ring 27 is installed in the lower sealing housing 26;

[0046] A central tube 21 is provided in the disc spring housing 20, and a threaded shaft 25 is provided in the threaded housing 24; the central tube 21 and the threaded shaft 25 are connected through a falling prevention tube 23;

[0047] The central tube 21 includes an upper tube column and a lower tube column. A disc spring 19 is installed in the annular space formed by the upper tube column and the disc spring housing 20; a central opening 2102 is provided on the lower tube column, and two sealing rings 22 are installed in the annular space formed by the lower tube column and the disc spring housing 20, and the two sealing rings 22 are distributed on the upper and lower sides of the central opening 2102.

[0048] An annular groove 2101 is provided on the upper pipe string of the central pipe 21, which is used to connect the lower hydraulic chamber and the annulus when the torque transmission is disconnected. A sealing ring 16 is installed on the upper end of the central pipe 21, which is used to seal the second opening 102 of the internal flow path between the lower hydraulic chamber and the upper joint 1 when the torque transmission is disconnected.

[0049] The working process of the present invention is as follows:

[0050] Initial state: The disc spring 19 is in a pre-tightened state. Under the action of the disc spring 19, the threaded mandrel is located at the lower dead center. The drilling fluid in the internal flow path of the tool flows into the lower hydraulic chamber of the piston 13 through the second opening 102 of the upper joint 1. The annulus drilling fluid is connected to the upper hydraulic chamber of the piston 13 through the first opening 1101. The tool is installed above the positive displacement motor. The liquid pressure inside the tool is higher than the liquid pressure in the annulus. The liquid pressure in the lower hydraulic chamber of the piston 13 is higher than the upper hydraulic chamber. The piston 13 generates an upward axial force, and the axial force compresses the friction plates through the push rod 10 and the pressure plate 9 to achieve torque transmission.

[0051] Working state 1: The torque transmission path is from the upper joint 1 to the friction plates, from the friction plates to the spline housing 11, from the spline housing 11 to the connection housing 17, from the connection housing 17 to the disc spring housing 20, from the disc spring housing 20 to the threaded housing 24, and from the threaded housing 24 to the threaded shaft 25. During the drilling process, the tool rotates with the drill string system. When the reverse torque of the bit generates violent fluctuations and the torque transmitted by the drill string exceeds the set contraction torque of the threaded shaft 25 of the tool, the axial force generated by the screw pair is greater than the pre-tightening force of the disc spring 19, the threaded shaft 25 contracts, the drill string torque decreases, and the threaded shaft 25 extends to achieve the function of reducing bit vibration.

[0052] Working state 2: When the bit jams or gets stuck, the bit stops rotating, the drill string torque continues to increase, the threaded shaft 25 contracts, driving the anti-drop pipe 23 and the central pipe 21 to move upward. When the threaded shaft 25 contracts to the limit position, the sealing ring on the central pipe 21 seals the second opening 102 of the upper joint 1, the lower hydraulic chamber of the piston is connected to the annulus, the liquid pressure in the lower hydraulic chamber of the piston decreases to the same as that in the annulus, the piston moves downward under the action of the spring 12, the friction plates are relaxed, the tool disconnects the torque transmission, and the ground-monitored torque suddenly becomes smaller, realizing the functions of drill string protection and bit jamming and sticking.

[0053] Working state 3: After the torque transmission is disconnected, when the drill string is lifted, the central pipe 21, the anti-drop pipe 23, and the threaded shaft 25 move downward under the action of the disc spring 19, the second opening 102 of the upper joint 1 is reopened, the channel between the lower hydraulic chamber of the piston and the annulus is closed, the liquid pressure in the lower hydraulic chamber of the piston is restored, the piston 13 generates an axial force to compress the friction plates, and the torque transmission is restored.

[0054] Using the above tools, a method for monitoring drill bit sticking and differential sticking is as follows. Specifically, during normal drilling, by monitoring the torque of the drill string, the torque fluctuates within a certain range, and the fluctuation amplitude is smaller than that without using the drill bit sticking and differential sticking monitoring tool. When the ground monitors that the torque of the drill string increases and suddenly becomes smaller after increasing to the limit torque set by the tool, and the limit torque set by the tool is less than the ultimate strength of the drill string, it indicates that sticking or differential sticking has occurred downhole. Slowly lift the drill string. If the drill string can be lifted, it indicates that sticking has occurred. If the drill string cannot be lifted, it indicates that differential sticking has occurred.

Claims

1. A drill bit jam monitoring tool, characterized by: Including torque clutch mechanism and drill jam monitoring mechanism; The torque clutch mechanism comprises an upper joint (1), an upper sealing shell (3), an upper sealing ring (2), a bearing shell (5), a thrust series bearing (4), a bearing inner ring fixing nut (6), a spline shell (11), a friction plate inner disk (7), a friction plate outer disk (8), a pressure plate (9), a push rod (10), a piston (13), a piston sealing ring (14), a piston spring (12), a sealing nut sleeve (15), a connecting shell (17), and a one-way valve (18); The outer diameter of the upper joint (1) decreases from top to bottom, and is described as shaft section I, shaft section II, shaft section III, shaft section IV and shaft section V in sequence; The shaft section I is provided with a threaded box for connecting the upper drill string; The upper sealing ring (2) is installed in the sealing groove of the upper sealing shell (3), the upper sealing shell (3) is sleeved on the upper joint (1), and the upper sealing ring (2) forms a seal with the surface of the shaft end II of the upper joint (1); the inner ring of the thrust string bearing (4) is sleeved on the shaft section III of the upper joint (1), and is positioned and fixed by the bearing inner ring fixing nut (6); the outer ring of the thrust string bearing (4) is sleeved in the bearing housing (5), and the thrust string bearing (4) is positioned and fixed by the upper sealing shell (3) and the bearing housing (5) being threadedly connected, and the upper joint (1) and the bearing housing (5) can rotate freely relative to each other; The shaft section IV of the upper joint (1) is covered with a spline housing (11), and a boss is provided in the middle of the spline housing (11) to divide the inner space into two parts, the upper part, the inner hole of the upper part is provided with an inner spline (1102), and the outer disc of the friction plate (8) is meshed with the inner spline (1102) of the spline housing (11) through the outer spline; the inner hole wall of the lower part is smooth and is used to install the piston (13); the shaft section IV of the upper joint (1) is provided with an outer spline, and the inner disc of the friction plate (7) is meshed with the inner spline (1102) of the shaft section IV of the upper joint (1) through the inner spline 1102 The outer spline is meshed; the inner friction plate (7) and the outer friction plate (8) are staggeredly installed to form a friction plate, and a pressure plate (9) and a push rod (10) are arranged below. The push rod (10) passes through a through hole (1103) on a boss of the spline housing (11), and the two ends of the push rod (10) are respectively connected to the pressure plate (9) and the piston (13); the upper and lower ends of the spline housing (11) are respectively connected to the bearing housing (5) and the connecting housing (17) through threads, and the friction plate transmits the torque of the upper joint (1) to the spline housing (11) through friction force; The piston (13) is provided with a sealing groove, in which a piston sealing ring (14) is provided. The piston (13) divides the smooth lower part of the inner wall of the spline housing (11) into two chambers. The upper hydraulic chamber is connected to the wellbore annulus through a first opening (1101) on the boss of the spline housing (11), and the lower hydraulic chamber is connected to the drilling fluid flow channel of the upper joint (1) through a second opening (102) on the shaft section V of the upper joint (1). The piston spring (12) is installed in the upper hydraulic chamber to provide a downward thrust to move the piston downward in the torque transmission disconnected working state. A one-way valve (18) is mounted on the connecting housing (17); The sealing nut sleeve (15) is installed on the shaft section V of the upper joint (1) through threads; The drill bit jam monitoring mechanism comprises a disc spring housing (20), a center tube (21), a disc spring (19), an anti-drop tube (23), a sealing ring (22), a threaded housing (24), a threaded shaft (25), a lower sealing housing (26), and a lower sealing ring (27); The upper end of the disc spring housing (20) is connected to the connecting housing (17) through a threaded buckle, and the lower end is connected to the threaded housing (24) through a threaded buckle. The lower end of the threaded housing (24) is connected to the lower sealing housing (26) through a threaded buckle; a lower sealing ring (27) is installed in the lower sealing housing (26); A central tube (21) is arranged in the disc spring housing (20), and a threaded shaft (25) is arranged in the threaded housing (24); the central tube (21) and the threaded shaft (25) are connected via an anti-dropping tube (23); The center tube (21) comprises an upper tube column and a lower tube column, wherein a disc spring (19) is installed in an annular space formed by the upper tube column and the disc spring housing (20); a center opening (2102) is provided on the lower tube column, and two sealing rings (22) are installed in the annular space formed by the lower tube column and the disc spring housing (20), and the two sealing rings (22) are distributed on the upper and lower sides of the center opening (2102); An annular groove (2101) is provided on the upper end of the center pipe (21) for connecting the lower hydraulic chamber and the annulus when the torque transmission is disconnected. A sealing ring (16) is installed on the upper end of the center pipe (21) for sealing the lower hydraulic chamber and the second opening (102) of the internal flow channel of the upper joint (1) when the torque transmission is disconnected.

2. A drill bit jam monitoring method, characterized in that: A drill bit jam monitoring tool as claimed in claim 1 is used; During normal drilling, by monitoring the drill string torque, the torque fluctuates within the set range, and the fluctuation amplitude is smaller than that when the drill bit jamming and bit sticking monitoring tool is not used. When the drill string torque is monitored to increase on the ground, it suddenly decreases after increasing to the limit torque set by the tool. The limit torque set by the tool is less than the ultimate strength of the drill string, indicating that the drill bit is jammed or stuck in the well. Slowly lift the drill string. If the drill string can be lifted, it means that the drill bit is jammed. If the drill string cannot be lifted, it means that the drill bit is stuck.

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