CN112832672B

CN112832672B - Underground power drilling tool with monitoring screw loosening function

Info

Publication number: CN112832672B
Application number: CN202011289949.XA
Authority: CN
Inventors: 宋刚毅; 白芬玉
Original assignee: Kingdream PLC; Sinopec Oilfield Equipment Corp
Current assignee: Sinopec Oilfield Equipment Corp
Priority date: 2020-11-17
Filing date: 2020-11-17
Publication date: 2023-05-02
Anticipated expiration: 2040-11-17
Also published as: CN112832672A

Abstract

The application relates to a power drilling tool in pit with monitor screw thread is not hard up belongs to power drilling tool technical field, includes: the power drilling tool comprises shells which are sequentially connected along the axial direction of the power drilling tool, and two adjacent shells are connected through screw threads; and the monitoring unit comprises an on-off ring and a conductor assembly, wherein the on-off ring and the conductor assembly are positioned between two adjacent shells, and when the two adjacent shells rotate relatively, the on-off ring is connected with or disconnected from the conductor assembly. The utility model provides a power drilling tool in pit adopts the mode of direct monitoring, utilizes the casing to release the preceding screw thread and can become flexible and produce the characteristics of relative slip, and whether the relative slip is in order to judge whether the screw thread is not flexible between the inspection casing through adding circuit break-make ring detection circuit on the casing and switch on or off. The device has the characteristics of accuracy and uniqueness of monitoring signals, simple structure and high reliability.

Description

Underground power drilling tool with monitoring screw loosening function

Technical Field

The application relates to the technical field of power drilling tools, in particular to an underground power drilling tool with a screw thread loosening monitoring function.

Background

In petroleum and natural gas exploitation, the application of the underground power drilling tool is more and more widespread, the power drilling tool drives a drill bit to realize the drilling of stratum, the underground power drilling tool is driven by drilling fluid pumped by ground equipment, during operation, the drilling fluid is pumped into the underground power drilling tool, and the power drilling tool converts hydraulic energy into kinetic energy to drive the drill bit at the bottom of the well to rotate. Common power drills have two types: screw drilling tools and turbine drilling tools.

For the screw drilling tool, drilling fluid enters the stator shell, a rotor screw eccentric with the stator shell is driven to rotate, and the rotor screw drives a universal shaft and a transmission shaft connected with the rotor screw to rotate, so that a drill bit at the lower end of the drilling tool is driven to rotate. The turbine drilling tool adopts one-stage or multi-stage turbine sections to provide torque for a drill bit at the lower end of the drilling tool, each stage consists of a stator which does not move and a rotor which rotates, the rotor is connected with a shaft, drilling fluid is led into the rotor by the stator, and rotor blades rotate under the action of the drilling fluid to provide torque for the drill bit at the lower end of the drilling tool.

The shell is a main supporting system of the power drilling tool, and the shells of all functional sections of the power drilling tool are mutually fastened together under the action of larger torsion by the thread pin and the box, so that the power drilling tool is integrated. The power drilling tool can meet various working condition actions in the pit, reactive torque impact between buckles can be formed under the action of certain working condition factors, and the fastening force between screw threads can be reduced due to repeated reactive torque impact. When the reactive torque instantaneously exceeds the screw thread torque, looseness between the male buckle and the female buckle occurs, reverse rotation occurs, a tripping phenomenon occurs when the reverse rotation reaches the screw thread connection limit position, the lower body is caused to fall off, and the whole section of the lower body is seriously caused to fall into the well. The tripping and falling of the power drilling tool can cause huge loss to drilling, well stopping and waterlogging are needed, and the side drilling to be filled or the whole well to be filled, which cannot be salvaged, are scrapped.

In the related art, the tripping of the power drilling tool is prevented at home and abroad mainly by improving the processing technology and the structure, setting the service time and the like, but the tripping fault cannot be prevented effectively. The abnormal parameter analysis of pump pressure, bit pressure, torque and the like can only judge whether the tripping is carried out, and the occurrence of the tripping cannot be predicted. At present, some domestic and foreign enterprises can reflect drilling faults of drilling tools to different degrees by adopting technical means such as an underground fault monitoring system and the like, so that the accuracy of drilling tool fault judgment is greatly improved, but no good monitoring mode can be predicted for tripping the sudden non-precursor specific drilling tool failure phenomenon, and related solutions are not found in related documents.

Disclosure of Invention

The embodiment of the application provides an underground power drilling tool with a screw thread loosening monitoring function, so as to solve the problem that tripping faults of the power drilling tool cannot be effectively prevented in the related art.

The embodiment of the application provides a downhole power drilling tool with monitoring screw loosening, comprising:

the power drilling tool comprises shells which are sequentially connected along the axial direction of the power drilling tool, and two adjacent shells are connected through screw threads;

and the monitoring unit comprises an on-off ring and a conductor assembly, wherein the on-off ring and the conductor assembly are positioned between two adjacent shells, and when the two adjacent shells rotate relatively, the on-off ring is connected with or disconnected from the conductor assembly.

In some embodiments: the on-off ring is positioned on the end face of one of the two adjacent shells, and the conductor assembly is positioned on the end face of the other of the two adjacent shells.

In some embodiments: one of the shell is provided with an annular groove for accommodating the on-off ring, the on-off ring is positioned in the annular groove, and insulating glue insulated from the on-off ring is coated in the annular groove.

In some embodiments: the on-off ring comprises a metal conducting ring, wherein a plurality of grooves which are arranged at intervals are formed in the inner ring or the outer ring of the metal conducting ring along the circumferential direction of the metal conducting ring, and arc-shaped blocks made of insulating materials are embedded in the grooves.

In some embodiments: and a conductive rib communicated with the conductor assembly is formed between two adjacent arc-shaped blocks, and the arc length of the conductive rib is smaller than that of the arc-shaped block.

In some embodiments: the other end face of the shell is provided with a mounting hole for accommodating the conductor assembly, and the conductor assembly is positioned in the mounting hole and is abutted to the on-off ring.

In some embodiments: the conductor assembly comprises an insulating tube and a conductor pressure head positioned in the insulating tube, a metal spring pushing the conductor pressure head to move towards the on-off ring is further arranged in the insulating tube, and a wire is connected to the conductor pressure head and/or the metal spring.

In some embodiments: one end of the insulating tube is provided with a limiting step for controlling the movement range of the conductor pressure head, the other end of the insulating tube is provided with an insulating pressure cover, the insulating pressure cover is provided with a threading hole penetrating into the wire, and the top end of the conductor pressure head is a dome.

In some embodiments: the monitoring unit further comprises a circuit board, the circuit board is located in the shell, at least two groups of conductor assemblies are arranged, one group of conductor assemblies are always communicated with the on-off ring, the other group of conductor assemblies are communicated with or disconnected from the on-off ring when two adjacent shells rotate relatively, and the input ends of the circuit board are respectively and electrically connected with the two groups of conductor assemblies.

In some embodiments: the shell comprises a bypass valve shell, an anti-falling shell, a stator shell, a universal shaft shell and a transmission shaft shell which are sequentially connected in a threaded manner along the axial direction of the power drilling tool, wherein the two ends of the anti-falling shell, the stator shell and the universal shaft shell are respectively provided with an on-off ring or a conductor assembly, and the bottom end of the bypass valve shell and the top end of the transmission shaft shell are respectively provided with the on-off rings or the conductor assemblies.

The beneficial effects that technical scheme that this application provided brought include:

the embodiment of the application provides an underground power drilling tool with a function of monitoring screw loosening, and as the underground power drilling tool is provided with the power drilling tool and a monitoring unit, the power drilling tool comprises shells which are sequentially connected along the axial direction of the power drilling tool, and two adjacent shells are connected through screw threads; the monitoring unit comprises an on-off ring and a conductor assembly, wherein the on-off ring and the conductor assembly are positioned between two adjacent shells, and when the two adjacent shells rotate relatively, the on-off ring is connected with or disconnected from the conductor assembly.

Therefore, the downhole power drilling tool is characterized in that the downhole power drilling tool can rotate relatively after the threads of the shells are loosened, and the on-off rings and the conductor assemblies are respectively embedded between two adjacent shells. When two adjacent shells rotate relatively, namely after screw threads are loosened, the on-off ring is connected or disconnected with the conductor assembly, and an electric signal is transmitted to the circuit board, and the circuit board transmits and uploads the processed signal to the MWD probe. The underground power drilling tool adopts a direct monitoring mode, utilizes the characteristic that screw threads can loosen and generate relative sliding before the shell is tripped, and checks whether the screw threads loosen or not by adding a circuit on-off ring on the shell to detect whether a circuit is connected or disconnected or not and checking whether the circuit is connected or disconnected or not. The device has the characteristics of accuracy and uniqueness of monitoring signals, simple structure and high reliability.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic structural diagram of an embodiment of the present application;

FIG. 2 is an enlarged view of a portion of FIG. 1 at A;

FIG. 3 is a partial enlarged view at B in FIG. 1;

FIG. 4 is a schematic diagram of an embodiment of an on-off ring and conductor assembly;

FIG. 5 is a front view of the structure of an on-off ring according to an embodiment of the present application;

FIG. 6 is a structural half cross-sectional view of an on-off ring according to an embodiment of the present application;

fig. 7 is a structural exploded view of a conductor assembly according to an embodiment of the present application.

Reference numerals:

1. a power drill; 11. a bypass valve housing; 12. an anti-drop housing; 13. a stator housing; 14. a cardan shaft housing;

2. a monitoring unit; 21. an on-off ring; 22. a conductor assembly; 23. a circuit board; 211. a metal conductive ring; 212. an arc-shaped block; 221. an insulating tube; 222. a conductor ram; 223. a metal spring; 224. an insulating gland; 225. and (5) conducting wires.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present application based on the embodiments herein.

The embodiment of the application provides a downhole power drilling tool with a screw thread loosening monitoring function, which can solve the problem that the tripping fault of the power drilling tool cannot be effectively prevented in the related art.

Referring to fig. 1-4, embodiments of the present application provide a downhole motor with monitoring screw loosening, comprising:

the power drilling tool 1 comprises shells which are sequentially connected along the axial direction of the power drilling tool 1, wherein the shells are of hollow pipe structures, and two adjacent shells are connected through screw threads. The power drill 1 of the present application may be a screw drill or a turbine drill, and the present embodiment will be described in detail by taking the screw drill as an example. The housing of the present embodiment includes a bypass valve housing 11, a drop preventing housing 12, a stator housing 13, a cardan shaft housing 14 and a propeller shaft housing (not shown in the drawings) which are screwed in order.

The monitoring unit 2, the monitoring unit 2 includes an on-off ring 21 and a conductor assembly 22 between two adjacent housings, when the two adjacent housings rotate relatively, the on-off ring 21 is connected with or disconnected from the conductor assembly 22. When two adjacent shells rotate relatively, the on-off ring 21 and the conductor assembly 22 are triggered to be connected or disconnected, and the wellhead detection equipment can directly judge and predict whether loosening and tripping of screw threads of the shells occur through the on-off ring 21 and the conductor assembly 22.

In some alternative embodiments: referring to fig. 2-4, an embodiment of the present application provides a downhole motor with monitoring screw loosening, wherein an on-off ring 21 of the downhole motor is located on an end face of one of two adjacent housings, and a conductor assembly 22 is located on an end face of the other of the two adjacent housings. The present embodiment is described taking the case of a screw-coupled bypass valve housing 11 and anti-drop housing 12 as an example.

An annular groove for accommodating the on-off ring 21 is formed in the bottom end face of the bypass valve housing 11 (i.e., the end face of the root of the external thread of the bypass valve housing 11), the on-off ring 21 is located in the annular groove, insulating glue insulated from the on-off ring 21 is coated in the annular groove, and the insulating glue is used for avoiding electric conduction between the on-off ring 21 and the bypass valve housing 11.

A mounting hole for accommodating the conductor assembly 22 is formed in the top end surface of the anti-drop housing 12 (i.e., the top end surface of the internal thread of the anti-drop housing 12), and the conductor assembly 22 is positioned in the mounting hole and abuts against the on-off ring 21. The trigger conductor assembly 22 and the on-off ring 21 are switched from the off state to the on state or from the on state to the off state upon relative rotation of the bypass valve housing 11 and the drop prevention housing 12.

In this embodiment, the on-off ring 21 is fixedly installed in the annular groove on the bottom end face of the bypass valve housing 11, the conductor assembly 22 is installed in the end face installation hole on the top end of the anti-drop housing 12, the integrated installation of the on-off ring 21 and the conductor assembly 22 with the housing of the power drilling tool 1 is realized, the housing structure and the strength of the power drilling tool 1 are not affected, the processing is easy, and the service life and the reliability are high.

In some alternative embodiments: referring to fig. 5 and 6, an embodiment of the present application provides a downhole power drilling tool with screw loosening monitoring, wherein an on-off ring 21 of the downhole power drilling tool includes a metal conductive ring 211, 2-20 grooves arranged at intervals are formed in an inner ring or an outer ring of the metal conductive ring 211 along a circumferential direction of the metal conductive ring 211, and an arc block 212 of an insulating material is embedded in each groove. A conductive rib, which is in conduction with the conductor assembly 22, is formed between two adjacent arc blocks 212, and the conductive rib and the metal conductive ring 211 are in an integrated structure. To facilitate accurate installation, the arc length of the conductive ribs is less than the arc length of the arcuate blocks 212.

When the bypass valve housing 11 and the drop preventing housing 12 are fastened to each other in place, the conductor assembly 22 abuts against the arc-shaped block 212, the electrical circuit between the on-off ring 21 and the conductor assembly 22 is in an off state, and the monitoring unit 2 does not send an alarm signal to the wellhead detection device when the power drill 1 is in downhole drilling operation. When the bypass valve housing 11 and the anti-drop housing 12 rotate relatively, and the screw threads between the bypass valve housing 11 and the anti-drop housing 12 are loosened, the conductor assembly 22 is abutted with the conductive ribs, an electric loop between the on-off ring 21 and the conductor assembly 22 is in a conducting state, and the monitoring unit 2 sends an alarm signal to wellhead detection equipment for the first time during downhole drilling operation of the power drilling tool 1.

In some alternative embodiments: referring to fig. 4 and 7, embodiments of the present application provide a downhole motor with monitoring screw loosening, the conductor assembly 22 of which includes an insulating tube 221 and a conductor ram 222 positioned within the insulating tube 221. The top end of the conductor ram 222 is a dome to ensure that the head of the conductor ram 222 reliably contacts and slides with the on-off ring 21. Also provided in the insulating tube 221 is a metal spring 223 for urging the conductor ram 222 to move toward the on-off ring 21, the metal spring 223 is preferably but not limited to a compression coil spring for ensuring a reliable contact force between the conductor ram 222 and the on-off ring 21, and the conductor ram 222 can operate normally even if worn. A wire 225 is connected to the conductor ram 222 or the metal spring 223, and the wire 225 is used to complete an external circuit.

A limit step for controlling the movement range of the conductor ram 222 is arranged at the top end of the insulating tube 221, and the limit step is used for controlling the movement range of the conductor ram 222 towards the on-off ring 21 so as to prevent the conductor ram 222 from falling out of the insulating tube 221 under the pushing action of the metal spring 223. An insulating gland 224 is provided at the bottom end of the insulating tube 221, and the insulating gland 224 and the insulating tube 221 are used to prevent the conductor ram 222 and the metal spring 223 from conducting electricity with the drop-proof housing 12. The insulating gland 224 is provided with a threading hole penetrating the conducting wire 225, and the conducting wire 225 is connected to an external circuit through the threading hole of the insulating gland 224.

The conductor pressure head 222 is of a cylindrical structure with a thin upper part and a thick lower part, the conductor pressure head 222 is preferably made of copper material with good conductivity, the upper end of the conductor pressure head 222 can freely move in a limiting step, the inner diameter of the limiting step is smaller than the diameter of the lower end of the conductor pressure head 222, and the lower end of the conductor pressure head 222 can freely move in the insulating tube 221.

In some alternative embodiments: referring to fig. 1-3, embodiments of the present application provide a downhole motor with monitoring of loosening of threads, the monitoring unit of the downhole motor further comprising a circuit board 23, the circuit board 23 being located within the drop-proof housing 12. The conductor assemblies 22 are provided with at least two groups, wherein one group of conductor assemblies 22 is always conducted with the metal conducting ring 211 of the on-off ring 21, the other group of conductor assemblies 22 is conducted with or disconnected from the on-off ring 21 when the bypass valve shell 11 and the anti-drop shell 12 rotate relatively, and the input ends of the circuit board 23 are respectively electrically connected with the two groups of conductor assemblies 22 to form an electric loop. The circuit board 23 transmits the processed signals to the MWD probe for uploading to wellhead detection equipment.

Of course, the conductor assemblies 22 of the present embodiment are not limited to two sets, but may be configured such that a set of conductor assemblies 22 is electrically connected to the circuit board, and when a set of conductor assemblies 22 is provided, the on-off ring 21 is electrically connected to the housing, and the input end of the circuit board 23 is connected to the conductor assemblies 22 and the housing, respectively, to form an electrical circuit.

In some alternative embodiments: referring to fig. 1 to 3, the embodiment of the present application provides a downhole power tool with monitoring screw loosening, the housing of the downhole power tool including a bypass valve housing 11, a drop-proof housing 12, a stator housing 13, a cardan shaft housing 14 and a transmission shaft housing (not shown) which are screwed in sequence in the axial direction of the power tool 1. The two ends of the anti-drop shell 12, the stator shell 13 and the universal shaft shell 14 are respectively provided with an on-off ring 21 and a conductor assembly 22, and the bottom end of the bypass valve shell 11 and the top end of the transmission shaft shell are respectively provided with the on-off ring 21 or the conductor assembly 22.

When the on-off ring 21 is arranged at the top end of the anti-drop housing 12 and the conductor assembly 22 is arranged at the bottom end, the conductor assembly 22 matched with the bypass valve housing 11 is arranged at the bottom end of the bypass valve housing 11 connected with the anti-drop housing in a threaded manner, and the on-off ring 21 matched with the stator housing 13 is arranged at the top end of the stator housing 13.

When the on-off rings 21 are arranged at the top end and the bottom end of the anti-drop housing 12, the bottom end of the bypass valve housing 11 connected with the on-off rings is provided with a conductor assembly 22 matched with the bypass valve housing, and the top end of the stator housing 13 is provided with the conductor assembly 22 matched with the stator housing.

When the conductor assemblies 22 are arranged at the top end and the bottom end of the anti-drop shell 12, the bottom end of the bypass valve shell 11 connected with the anti-drop shell through threads is provided with an on-off ring 21 matched with the bypass valve shell, and the top end of the stator shell 13 is provided with an on-off ring 21 matched with the stator shell. The other adjacent shells analogize one time.

The on-off ring 21 and the conductor assembly 22 of the present application are not limited to being installed between two adjacent housings, but the on-off ring 21 and the conductor assembly 22 of the present application are also suitable for being installed between a drop-preventing rod, a rotor screw, a universal shaft and a transmission shaft which are sequentially screwed in the power drill 1.

Principle of operation

The embodiment of the application provides a downhole power drilling tool with a function of monitoring screw loosening, and as the downhole power drilling tool is provided with a power drilling tool 1 and a monitoring unit 2, the power drilling tool 1 comprises shells which are sequentially connected along the axial direction of the power drilling tool 1, and two adjacent shells are connected through screw threads; the monitoring unit 2 includes an on-off ring 21 and a conductor assembly 22 between the adjacent two housings, and when the adjacent two housings are rotated relatively, the on-off ring 21 is connected to or disconnected from the conductor assembly 22.

The downhole power drilling tool is characterized in that the downhole power drilling tool can rotate relatively after the threads of the shells are loosened, and an on-off ring 21 and a conductor assembly 22 are respectively embedded between two adjacent shells. When two adjacent shells rotate relatively, namely after screw threads are loosened, the on-off ring 21 is connected or disconnected with the conductor assembly 22, and an electric signal is transmitted to the circuit board 23, and the circuit board 23 transmits and uploads the processed signal to the MWD probe. The underground power drilling tool adopts a direct monitoring mode, utilizes the characteristic that screw threads are loosened and relatively slide before the casing is tripped, and detects whether a circuit is connected or disconnected by applying a circuit on-off ring 21 on the casing, and checks whether the casings relatively slide so as to judge whether the screw threads are loosened. The device has the characteristics of accuracy and uniqueness of monitoring signals, simple structure and high reliability.

In the description of the present application, it should be noted that the azimuth or positional relationship indicated by the terms "upper", "lower", etc. are based on the azimuth or positional relationship shown in the drawings, and are merely for convenience of description of the present application and simplification of the description, and are not indicative or implying that the apparatus or element in question must have a specific azimuth, be configured and operated in a specific azimuth, and thus should not be construed as limiting the present application. Unless specifically stated or limited otherwise, the terms "mounted," "connected," and "coupled" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

It should be noted that in this application, relational terms such as "first" and "second" and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The foregoing is merely a specific embodiment of the application to enable one skilled in the art to understand or practice the application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A downhole motor with thread loosening monitoring function, comprising:

the power drilling tool (1) comprises shells which are sequentially connected along the axial direction of the power drilling tool (1), and two adjacent shells are connected through screw threads;

the monitoring unit (2) comprises an on-off ring (21) and a conductor assembly (22) which are positioned between two adjacent shells, and when the two adjacent shells rotate relatively, the on-off ring (21) is connected with or disconnected from the conductor assembly (22);

the on-off ring (21) comprises a metal conducting ring (211), wherein a plurality of grooves which are arranged at intervals are formed in the inner ring or the outer ring of the metal conducting ring (211) along the circumferential direction of the metal conducting ring (211), and arc-shaped blocks (212) of insulating materials are embedded in the grooves;

a conductive rib which is communicated with the conductor assembly (22) is formed between two adjacent arc-shaped blocks (212), and the arc length of the conductive rib is smaller than that of the arc-shaped blocks (212);

the conductor assembly (22) comprises an insulating tube (221) and a conductor pressure head (222) positioned in the insulating tube (221), a metal spring (223) pushing the conductor pressure head (222) to move towards the on-off ring (21) is further arranged in the insulating tube (221), and a wire (225) is connected to the conductor pressure head (222) and/or the metal spring (223).

2. A downhole motor with thread loosening monitoring function as recited in claim 1, wherein:

the on-off ring (21) is positioned on the end face of one of the two adjacent shells, and the conductor assembly (22) is positioned on the end face of the other of the two adjacent shells.

3. A downhole motor with thread loosening monitoring function as recited in claim 2, wherein:

an annular groove for accommodating the on-off ring (21) is formed in the end face of one of the shells, the on-off ring (21) is located in the annular groove, and insulating glue insulated from the on-off ring (21) is coated in the annular groove.

4. A downhole motor with thread loosening monitoring function as recited in claim 2, wherein:

the other end face of the shell is provided with a mounting hole for accommodating the conductor assembly (22), and the conductor assembly (22) is positioned in the mounting hole and is abutted to the on-off ring (21).

5. A downhole motor with thread loosening monitoring function as recited in claim 1, wherein:

one end of the insulating tube (221) is provided with a limiting step for controlling the movement range of the conductor pressure head (222), the other end of the insulating tube (221) is provided with an insulating pressure cover (224), the insulating pressure cover (224) is provided with a threading hole penetrating into the conducting wire (225), and the top end of the conductor pressure head (222) is a dome.

6. A downhole motor with thread loosening monitoring function as claimed in claim 1 or 2, wherein:

the monitoring unit (2) further comprises a circuit board (23), the circuit board (23) is located in the shell, the conductor assemblies (22) are at least provided with two groups, one group of conductor assemblies (22) is conducted with the on-off ring (21), the other group of conductor assemblies (22) is conducted with or disconnected from the on-off ring (21) when two adjacent shells rotate relatively, and the input ends of the circuit board (23) are respectively electrically connected with the two groups of conductor assemblies (22).

7. A downhole motor with thread loosening monitoring function as recited in claim 1, wherein:

the motor drill is characterized in that the housing comprises a bypass valve housing (11), an anti-falling housing (12), a stator housing (13), a universal shaft housing (14) and a transmission shaft housing which are sequentially connected in a threaded mode along the axial direction of the motor drill (1), two ends of the anti-falling housing (12), the stator housing (13) and the universal shaft housing (14) are respectively provided with an on-off ring (21) or a conductor assembly (22), and the bottom end of the bypass valve housing (11) and the top end of the transmission shaft housing are provided with the on-off ring (21) or the conductor assembly (22).