Drill bit dynamic stabilization device

Abstract

The present invention discloses a drill bit dynamic stabilization device, which is mainly composed of a drill bit body, a guide cover, a stator, a rotor, a spring, a positioning pin, a gear rack, and a limit tooth. The stator is fixedly installed on the inner wall of the drill bit body, the rotor is installed in the middle of the stator, the guide cover is installed on the upper part of the rotor, the gear rack is installed inside the rotor, a spring is installed between the gear rack and the rotor, the positioning pin is installed on the rotor, a guide groove is processed on the gear rack, the positioning pin cooperates with the guide groove, and the limit tooth is installed on the gear rack. The drill bit dynamic stabilization device is installed inside the drill bit, and utilizes hydraulic power to drive the regular reciprocating motion of the stabilizing teeth to dynamically control the cutting depth of the drill bit, so as to achieve the purpose of reducing the irregular influence of factors such as rocks and engineering parameters by the regular motion of the stabilizing teeth, so that the drill bit is in a regular dynamic stable rock breaking state, which not only protects the drill bit and prolongs its service life, but also further improves the drilling rock breaking efficiency.

Description

Technical Field

[0001] The invention belongs to the field of oil and gas drilling, coalbed methane drilling, geological exploration and mining drilling devices, and mainly relates to a drill bit dynamic stabilization device in a downhole drilling tool. Background Art

[0002] In deep wells, ultra-deep wells and complex geological conditions, we often encounter difficult-to-drill rocks such as granite, hard sandstone and conglomerate, which are generally characterized by high hardness, strong heterogeneity, poor drillability and high abrasiveness. The commonly used rock-breaking drill bits often have problems such as slow rock breaking speed, short drill bit life and high rock breaking cost when breaking such rocks, which brings new risks and challenges to drilling. During the drilling process, the drill bit needs to drill through different formations. When the lithology of the formation changes, the drilling speed will change accordingly, which is easy to cause stick-slip vibration of the drill bit, and even cause the failure of the drill bit and the downhole drilling tool assembly, resulting in increased drilling costs and reduced efficiency due to complex accidents at the bottom of the well. Usually, the drilling speed is mainly achieved by controlling the drilling pressure and rotation speed, or by controlling the speed of the bottom hole motor, but these control methods have a certain lag for the bottom hole drill bit. With the rapid development of drill bit technology, in order to avoid drill bit damage caused by lower drilling pressure and higher speed conditions, a parameter combination of higher drilling pressure and lower speed is gradually adopted to improve drilling performance. However, it is difficult to avoid torsional instability caused by higher drilling pressure and lower rotation speed, which in turn causes stick-slip vibration. The drill bit cutting depth control technology can effectively eliminate the stick-slip vibration of the drill bit, but while this technology expands the application range of the drill bit, it also limits the cutting ability of the drill bit, that is, when drilling in relatively soft rock formations, it is necessary to increase the cutting depth of the drill bit to increase the rock breaking volume of the drill bit. When drilling in relatively hard rock formations, it is necessary to reduce the cutting depth of the drill bit to prevent the hard rock from damaging the drill bit cutting teeth, but the conventional drill bit cutting depth control device cannot be adjusted in real time and is difficult to adapt to changes in the bottom rock properties, so the scope of use is limited. The stick-slip vibration of the drill bit is random and irregular, which is caused by the heterogeneity of the rock and the irregularity of the engineering parameters. In the prior art, conventional drill bits cannot automatically adapt to control the cutting depth of the drill bit according to changes in the rock properties, and the rock breaking efficiency and service life of the drill bit are low. Summary of the invention

[0003] In order to solve the above problems, maximize the rock breaking advantages of the drill bit, reduce the problems of premature breakage of the drill bit cutting teeth caused by unstable cutting depth of the drill bit, rock inhomogeneity and downhole vibration factors, low rock breaking efficiency of the drill bit and low service life of the drill bit, and further improve downhole safety, the present invention provides a drill bit dynamic stabilization device.

[0004] The purpose of the present invention is to provide a drill bit dynamic stabilization device for the fields of oil and gas drilling, geological exploration, and mine drilling, which is a device that can control the drill bit to be in a regular dynamic stability state, minimize the irregular adverse effects caused by factors such as rock heterogeneity and engineering parameter fluctuations, further improve the drill bit rock breaking efficiency, and extend the service life of the drill bit. At the same time, it must meet the technical requirements and equipment requirements of existing drilling processes, and the drill bit dynamic stabilization device has a simple structure, low cost, and easy maintenance.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] The drill bit dynamic stabilization device includes a drill bit body 1 and cutting teeth and a hollow flow channel arranged on the drill bit body 1. A stator 3, a rotor 4, a tooth rack 7 and a limit tooth 8 are also arranged in the hollow flow channel of the drill bit body 1; wherein the stator 3 is fixedly mounted on the inner wall of the drill bit body 1; the rotor 4 is mounted in the middle of the stator 3; the tooth rack 7 is mounted on the lower part of the rotor 4, and forms an axial sliding rotation limit fit with the rotor 4; the limit tooth 8 is mounted on the outer peripheral shoulder of the lower end of the tooth rack 7, and is plugged into the limit hole at the bottom of the drill bit body 1, and the limit tooth 8 reciprocates downward along the limit hole of the drill bit body 1.

[0007] The above scheme further comprises:

[0008] The rotor 4 and the gear rack 7 are matched with each other through a positioning pin 6 and a continuous “W”-shaped guide groove 9 .

[0009] A continuous “W”-shaped guide groove 9 is provided on the outer circumferential surface of the gear rack 7 . The positioning pin 6 is installed on the rotor 4 , and the positioning pin 6 is slidably matched with the guide groove 9 .

[0010] A spring 5 is installed between the gear carrier 7 and the rotor 4 .

[0011] There are more than two limiting teeth 8 , which are evenly arranged along the outer peripheral shoulder of the gear rack 7 .

[0012] The outer end of the limiting tooth 8 is in the form of a cone or an arc.

[0013] A deflector 2 is also installed on the upper part of the rotor 4 .

[0014] The space between the rotor 4, the spring 5 and the gear rack 7 is filled with lubricating oil.

[0015] The advantages of the present invention are: (1) the drill bit is in a regular, low-amplitude micro-vibration state, that is, a dynamic equilibrium stable state, which minimizes the irregular adverse effects caused by factors such as rock heterogeneity and engineering parameter fluctuations, improves the rock breaking efficiency of the drill bit, and extends the service life of the drill bit. (2) The drill bit dynamic stabilization device also has the characteristics of simple structural design, reliable performance, convenient operation, low cost, etc., which is convenient for large-scale promotion and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the drill bit dynamic stabilization device of the present invention.

[0017] Figure 2 It is a schematic diagram of a gear rack of a drill bit dynamic stabilization device of the present invention.

[0018] Figure 3 It is a schematic diagram of the guide groove of the tooth rack of the drill bit dynamic stabilization device of the present invention.

[0019] In the figure: 1. drill bit body, 2. guide cover, 3. stator, 4. rotor, 5. spring, 6. positioning pin, 7. gear rack, 8. limit teeth, 9. guide groove. DETAILED DESCRIPTION

[0020] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0021] Example 1

[0022] See attached Figure 1-3 A drill bit dynamic stabilization device includes a drill bit body 1 and cutting teeth and a hollow flow channel arranged on the drill bit body 1. A stator 3, a rotor 4, a tooth rack 7 and a limit tooth 8 are also arranged in the hollow flow channel of the drill bit body 1; wherein the stator 3 is fixedly mounted on the inner wall of the drill bit body 1; the rotor 4 is mounted in the middle of the stator 3; the tooth rack 7 is mounted on the lower part of the rotor 4, and forms an axial sliding rotation limit fit with the rotor 4; the limit tooth 8 is mounted on the outer peripheral shoulder of the lower end of the tooth rack 7, and is plugged and matched with the limit hole at the bottom of the drill bit body 1, and the limit tooth 8 reciprocates downward along the limit hole of the drill bit body 1. A continuous "W"-shaped guide groove 9 is provided on the outer circumferential surface of the tooth rack 7, and the positioning pin 6 is mounted on the rotor 4, and the positioning pin 6 is slidably matched with the guide groove 9.

[0023] Example 2

[0024] On the basis of Example 1, it further comprises: a spring 5 is installed between the gear rack 7 and the rotor 4. The number of the limiting teeth 8 is more than 3, and they are evenly arranged along the outer peripheral shoulder of the gear rack 7. The outer end of the limiting teeth 8 is a conical or arc-shaped tooth. A guide cover 2 is also installed on the upper part of the rotor 4. The space between the rotor 4, the spring 5 and the gear rack 7 is filled with lubricating oil.

[0025] Example 3

[0026] See attached Figure 1The dynamic stabilization device of the drill bit mainly consists of a drill body 1, a guide cover 2, a stator 3, a rotor 4, a spring 5, a positioning pin 6, a tooth rack 7, a limiting tooth 8, and a guide groove 9. The stator 3 is fixedly mounted on the inner wall of the drill body 1, and the rotor 4 is mounted in the middle of the stator 3. The stator 3 and the rotor 4 are screw or turbine power mechanisms, which convert the kinetic energy of the drilling fluid into rotary power. The guide cover 2 is mounted on the upper part of the rotor 4, the tooth rack 7 is mounted inside the rotor 4, the spring 5 is mounted between the tooth rack 7 and the rotor 4, the positioning pin 6 is mounted on the rotor 4, and a continuous "W"-shaped guide groove 9 is machined on the outer surface of the tooth rack 7, and the positioning pin 6 and the guide groove 9 form a sliding fit. The limiting tooth 8 is mounted on the tooth rack 7. When the positioning pin 6 moves in the guide groove 9, it pushes the tooth rack 7 to move up and down, driving the limiting tooth 8 to repeatedly extend out of the drill body 1. The limiting tooth 8 is a bevel tooth or a column tooth, and the limiting tooth 8 is three or more groups, which are evenly arranged. The space between the rotor 4, the spring 5, and the tooth rack 7 is filled with lubricating oil. The positioning pin 6 and the guide groove 9 are one group or more than one group.

[0027] Working principle: During drilling, the drill bit body 1 is installed at the lower part of the drilling tool assembly. After the drilling fluid enters the drill bit body 1, it enters the stator 3 through the guide cover 2, and then enters the rotor 4. The cooperation between the stator 3 and the rotor 4 converts the kinetic energy of the drilling fluid into the rotational motion of the rotor 4. The rotation of the rotor 4 drives the positioning pin 6 to rotate. Since the positioning pin 6 cooperates with the guide groove 9, that is, the positioning pin 6 slides in the guide groove 9, and since the guide groove 9 is installed on the gear rack 7, the rotational motion of the rotor 4 drives the gear rack 7 to produce axial reciprocating motion. Since the limit tooth 8 is installed on the gear rack 7, the limit tooth 8 also produces axial reciprocating motion. When the gear rack 7 moves upward, on the one hand, the spring 5 is compressed and stores energy, and on the other hand, the limit tooth 8 retracts into the drill bit body 1. When the matching point between the positioning pin 6 and the guide groove 9 changes, the spring 5 releases energy and pushes the gear rack 7 to move downward. At this time, the limit tooth 8 also quickly extends from the drill bit body 1 and contacts the bottom rock. With the continuous flow of drilling fluid, the limit teeth 8 will regularly and pulsatingly extend out of the drill bit body 1. In the process of the drill bit rotating and breaking rocks, the reciprocating axial motion of the limit teeth 8 will limit the depth of the drill bit cutting teeth cutting into the rock, making it change regularly. In this way, the irregular contact between the conventional drill bit and the rock during rock breaking is transformed into a regular basis, thereby improving the rock breaking efficiency of the drill bit and extending its service life.

[0028] The field test results show that the drill bit dynamic stabilization device can fully meet the technical requirements of existing domestic drilling technology, increase the average mechanical drilling speed by 123%-218%, and extend the service life of the drill bit by more than 80%. Especially in the deep and ultra-deep well drilling process in the northwest and southwest of my country, the speed-up effect is very significant, which greatly shortens the drilling cycle, reduces drilling costs, and achieves great economic and social benefits.

Claims

1. A drill bit dynamic stabilization device, comprising a drill bit body (1) and cutting teeth and a hollow flow channel arranged on the drill bit body (1), characterized in that: A stator (3), a rotor (4), a tooth rack (7) and a limit tooth (8) are also arranged in the hollow flow passage of the drill body (1); wherein the stator (3) is fixedly mounted on the inner wall of the drill body (1); the rotor (4) is mounted in the middle of the stator (3); the tooth rack (7) is mounted on the lower part of the rotor (4) and forms an axial sliding rotation limit fit with the rotor (4); the limit tooth (8) is mounted on a convex shoulder on the outer peripheral edge of the lower end of the tooth rack (7) and is plug-fitted with a limit hole at the bottom of the drill body (1), and the limit tooth (8) reciprocates downward along the limit hole of the drill body (1); The rotor (4) and the gear rack (7) are matched with each other via a positioning pin (6) and a continuous W-shaped guide groove (9); the number of the limiting teeth (8) is more than two and they are evenly arranged along the outer peripheral shoulder of the gear rack (7); and a deflector (2) is also installed on the upper part of the rotor (4).

2. The drill bit dynamic stabilization device according to claim 1, characterized in that: A continuous W-shaped guide groove (9) is provided on the outer circumferential surface of the gear rack (7), and the positioning pin (6) is mounted on the rotor (4), and the positioning pin (6) is slidably matched with the guide groove (9).

3. The drill bit dynamic stabilization device according to claim 2, characterized in that: A spring (5) is installed between the gear rack (7) and the rotor (4).

4. The drill bit dynamic stabilization device according to any one of claims 1 to 3, characterized in that: The outer end of the limiting tooth (8) is in the form of a cone or an arc-shaped tooth.

5. The drill bit dynamic stabilization device according to claim 4, characterized in that: The space between the rotor (4), the spring (5) and the gear rack (7) is filled with lubricating oil.

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