Intelligent centralizer with multi-stage diameter change

Abstract

The invention relates to the technical field of oil drilling, and in particular to an intelligent straightener for realizing multi-stage diameter change, comprising a control module, a motion execution module, and a connection module; the control module comprises an MCU and a battery pack; the motion execution module comprises a flow channel control execution unit, a stroke control execution unit, and a piston extension execution unit; the flow channel control execution unit comprises a flow channel controller, a flow divider, a thrust ball bearing, an end cover, a transmission shaft, a magnetic coupler, a motor lower protective shell, a motor, and a motor upper protective shell; the stroke control execution unit comprises a stroke controller, a reset spring, and an electromagnet; the piston extension execution unit comprises a spiral push block, a piston cover, a fixing bolt, a piston, and a one-way valve; the connection module comprises an upper joint, an upper shell, and a lower shell; the invention can realize straightening and stabilizing functions under three different diameters, has a wider application range, and has stable working performance.

Description

Technical Field

[0001] The invention relates to the technical field of oil and gas resource drilling tools, and in particular to an intelligent centralizer for realizing multi-stage diameter change. Background Art

[0002] As time goes by, developed oil fields enter the stage of high water content and high recovery, and the production of major old oil fields decreases. Conventional oil field exploitation can no longer meet social and environmental needs, and the development of unconventional oil extraction technology has become extremely urgent. To solve this problem, we need to improve the key technologies and management technologies in the drilling process, improve drilling efficiency, thereby improving extraction efficiency and reducing extraction costs.

[0003] In the process of oil and gas well production, in order to control and adjust the wellbore inclination, a centralizer is required. Conventional fixed stabilizers can only be replaced when the drill is pulled out. However, frequent drilling stops, drilling and drilling down can easily cause scraping of the well wall and piston pulling, which not only increases the mud soaking time on the well wall, but also reduces the drilling efficiency and even causes the well wall to become unstable, leading to well collapse, blowout and other complex situations. Therefore, in the complex production process, a remote-controlled variable diameter centralizer that can effectively avoid the risk of accidents is urgently needed. Summary of the invention

[0004] The purpose of the present invention is to provide an intelligent stabilizer that can achieve multi-stage diameter change, and its outer diameter can be adjusted by remote control or downhole automatic control. Through this precise adjustment, the purpose of controlling the well inclination can be achieved, making the drilling process smoother and safer.

[0005] In order to achieve the above-mentioned purpose of the invention, the technical solution adopted by the present invention is: the intelligent centralizer for realizing multi-stage diameter change includes a control module, a motion execution module, and a connection module.

[0006] The control module is located in a protective housing on the motor. The control module includes an MCU, a driver, and a battery pack. The MCU controls the driver to realize the rotation of the DC motor and the on and off of the electromagnet.

[0007] The motion execution module includes a flow channel control execution unit, a stroke control execution unit, and a piston extension execution unit;

[0008] The flow channel control execution unit includes a flow channel controller, a diverter, a thrust ball bearing, an end cover, a transmission shaft, a magnetic coupler, a lower motor protection shell, a motor, and an upper motor protection shell; the lower motor protection shell and the upper motor protection shell are provided with 4 evenly distributed fan-shaped cavities, and the drilling fluid enters the flow channel controller through the cavity, and the lower motor protection shell and the upper motor protection shell are connected by threads; the motor is fixed in the upper motor protection shell by bolts, the magnetic coupler and the transmission shaft are connected by 4 groups of circumferentially evenly distributed bolts, and the end cover and the flow channel controller are connected by 4 groups of circumferentially evenly distributed bolts. The transmission shaft is fixed in the flow channel controller, and keyways are provided at both ends of the transmission shaft, and circumferential transmission between the transmission shaft and the magnetic coupler and the flow channel controller is realized through key connection; three circumferentially evenly distributed radial flow channel holes are provided near the end of the lower shell of the flow channel controller, and three flow channel holes corresponding to the flow channel controller are provided inside the flow divider, and the flow channel direction inside the flow divider is: from radial to axial; there is a thrust ball bearing between the flow channel controller and the flow divider, which avoids direct friction between the flow channel controller and the flow divider and reduces the driving torque of the motor. The thrust ball bearing realizes axial positioning through the shoulder inside the upper shell;

[0009] The stroke control execution unit includes a stroke controller, a reset spring, and an electromagnet; the stroke controller is provided with three spiral U-shaped grooves with different spiral lengths on the outside, and a circular hole with a depth of 8 mm is provided at the upper end of the spiral U-shaped groove; the reset spring is installed at the lower end of the stroke controller, and axial positioning is achieved through the shaft shoulder of the stroke controller and the shoulder in the lower shell. When the stroke controller moves axially, the reset spring is compressed or extended; the spiral push block and the stroke controller are connected by threads to achieve synchronous rotation. There are 3 electromagnets, and the outer shell of the electromagnet has threads, which are fixed in the corresponding threaded holes of the lower shell by threaded connection;

[0010] The piston extension execution unit includes a spiral push block, a piston cover, a fixing bolt, a piston, and a one-way valve; the interior of the spiral push block is a cylindrical cavity, and the external spiral spline consists of two sections, the first section is 3 spiral splines evenly distributed circumferentially, which cooperate with the spiral spline grooves inside the lower shell to realize the spiral motion guidance of the spiral push block, and the second section is 3 circumferentially evenly distributed variable thickness spiral splines, with a total of 3 sections, which contact the piston to realize the extension of the piston; the piston cover is spiral, and is provided with three evenly distributed piston holes and 8 countersunk threaded holes, which are movable There are 3 plug covers, which are evenly distributed along the circumference; the upper part of the piston is cylindrical, the lower part is a rectangular parallelepiped structure, and the bottom is an inclined surface, the inclination of which is consistent with the inclination of the variable thickness spiral spline of the spiral push block. There are 9 pistons, and a spring is provided between the piston and the piston cover to achieve the retraction of the piston; there are 3 one-way valves, which are evenly distributed along the circumference, and the outer shell of the one-way valve is provided with a thread, which is fixed in the corresponding threaded hole of the upper shell through a threaded connection; the piston cover is fixed to the lower shell by fixing bolts, and the number of the fixing bolts is 24;

[0011] The connection module includes an upper joint, an upper shell, and a lower shell; the outer portion of the lower shell has three circumferentially evenly distributed spiral grooves, each of which has three piston holes, and the inner portion of the lower shell has three circumferentially evenly distributed spiral grooves; the upper joint and the upper shell are connected by a tapered thread, the upper shell and the lower shell are connected by a tapered thread, the lower connecting thread of the lower shell is a tapered thread, and the inner thread of the upper joint is a tapered thread.

[0012] As a further technical solution of the present invention, O-rings are installed on the flow channel controller and the flow divider to prevent high-pressure drilling fluid from penetrating into the thrust ball bearing and affecting the life of the thrust ball bearing.

[0013] As a further technical solution of the present invention, the electromagnet is in a retracted state when not energized. When the electromagnet is energized, the positioning pin extends and moves along with the spiral of the stroke controller. After reaching the corresponding position, the positioning pin engages with the U-shaped spiral groove circular hole of the stroke controller to achieve stroke positioning.

[0014] As a further technical solution of the present invention, the motor is a DC motor. The rotation of the motor drives the flow channel of the flow channel controller to communicate with the flow channel of the diverter. The high-pressure drilling fluid enters through the flow channel opening, pushing the spiral push block to produce a downward spiral motion, pushing the piston to extend; when the piston retracts, the spiral push block moves upward in a spiral motion. At this time, the drilling fluid in the cavity between the spiral push block and the diverter is discharged from the tool through the one-way valve, avoiding the occurrence of pressure build-up that causes the spiral push block method to reset.

[0015] As a further technical solution of the present invention, the spiral angles of the U-shaped spiral groove of the spiral push block, the spiral spline of the stroke controller, and the spiral groove inside the lower shell are the same.

[0016] As a further technical solution of the present invention, the material of the return spring is alloy steel, and the processing method is hot rolling.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. Compared with the applicable wellbore diameter range of other variable diameter centralizers, the innovation of the present invention lies in that the travel controller and the electromagnet cooperate with each other to achieve the straightening and stabilizing function under three different diameters, and the applicable range is wider.

[0019] 2. A spiral transmission is used between the spiral push rod and the lower shell to push the piston out, which works stably and has a large load-bearing capacity during the operation of the multi-stage variable diameter intelligent centralizer.

[0020] 3. A magnetic coupler is used to realize the transmission between the motor and the flow channel controller, which effectively solves the sealing problem of the motor and the control circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The schematic diagram of the structure of the intelligent centralizer for realizing multi-stage diameter change of the present invention;

[0022] Figure 2 The AA cross-sectional view of the intelligent centralizer realizing multi-stage diameter change of the present invention;

[0023] Figure 3 This is a cross-sectional view of the intelligent centralizer BB that realizes multi-stage diameter change according to the present invention;

[0024] Figure 4 This is a partial enlarged view of the intelligent centralizer C for realizing multi-stage diameter change according to the present invention;

[0025] Figure 5 The working principle diagram of the intelligent centralizer for realizing multi-stage diameter change of the present invention;

[0026] Figure 6 It is a structural schematic diagram of the spiral push block of the intelligent centralizer that realizes multi-stage diameter change according to the present invention;

[0027] Figure 7 It is a structural schematic diagram of the intelligent centralizer stroke controller realizing multi-stage diameter change of the present invention;

[0028] Figure 8 This is a partial expanded view of the cam portion of the intelligent centralizer stroke controller that realizes multi-stage diameter change of the present invention;

[0029] Fig. 9 The invention provides a forward and reverse circuit diagram of the intelligent centralizer motor for realizing multi-stage diameter change;

[0030] Fig.10The intelligent centralizer electromagnet control circuit diagram for realizing multi-stage diameter change of the present invention;

[0031] Explanation of the reference numerals: 1-upper joint, 2-upper shell, 3-flow channel controller, 4-diverter, 5-screw push block, 6-lower shell, 7-piston cover, 8-fixing bolt, 9-stroke controller, 10-reset spring, 11-electromagnet, 12-piston, 13-check valve, 14-thrust ball bearing, 15-end cover, 16-drive shaft, 17-magnetic coupler, 18-lower protective shell of motor, 19-motor, 20-upper protective shell of motor, 21-MCU, 22-battery pack, 1701-outer rotor, 1702-permanent magnet, 1703-inner rotor. DETAILED DESCRIPTION

[0032] The present invention is further described below in conjunction with the drawings of the specification. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] See attached Figure 1 The present invention provides an intelligent centralizer for realizing multi-stage diameter change, characterized in that: the intelligent centralizer for realizing multi-stage diameter change comprises a control module, a motion execution module, and a connection module:

[0034] The control module is located in the protective housing 20 on the motor, and the control module includes an MCU 21 and a battery pack 22;

[0035] The motion execution module includes a flow channel control execution unit, a stroke control execution unit, and a piston extension execution unit;

[0036] The flow channel control execution unit includes a flow channel controller 3, a diverter 4, a thrust ball bearing 14, an end cover 15, a transmission shaft 16, a magnetic coupler 17, a lower motor protection shell 18, a motor 19, and an upper motor protection shell 20; the lower motor protection shell 18 and the upper motor protection shell 20 are provided with four evenly distributed fan-shaped cavities, and the drilling fluid enters the flow channel controller 3 through the cavity, and the lower motor protection shell 18 and the upper motor protection shell 20 are connected by threads; the motor 19 is fixed in the upper motor protection shell 20 by bolts, and the magnetic coupler 17 and the transmission shaft 16 are connected by four groups of circumferentially evenly distributed bolts, and the end cover 15 and The flow channel controllers 3 are connected by 4 groups of circumferentially uniformly distributed bolts to fix the transmission shaft 16 in the flow channel controller 3. Keyways are provided at both ends of the transmission shaft 16, and circumferential transmission between the transmission shaft 16 and the magnetic coupler 17 and the flow channel controller 3 is realized by key connection; the lower shell of the flow channel controller 3 is provided with 3 circumferentially uniformly distributed radial flow channel holes near the end, and the flow divider 4 is provided with 3 flow channel holes corresponding to the flow channel controller 3, and the flow channel direction inside the flow divider 4 is: from radial to axial; there is a thrust ball bearing 14 between the flow channel controller 3 and the flow divider 4, and the thrust ball bearing 14 is axially positioned by the shoulder inside the upper shell 2;

[0037] The stroke control execution unit includes a stroke controller 9, a reset spring 10, and an electromagnet 11; the stroke controller 9 is provided with three spiral U-shaped grooves with different spiral heights on the outside, and a circular hole with a depth of 8 mm is provided at the upper end of the spiral U-shaped groove; the reset spring 10 is installed at the lower end of the stroke controller 9, and axial positioning is achieved through the shaft shoulder of the stroke controller 9 and the shoulder in the lower shell 6. When the stroke controller 9 moves axially, the reset spring 10 is compressed or extended; the spiral push block 5 and the stroke controller 9 are connected by threads to achieve synchronous rotation. The number of the electromagnets 11 is 3, and the outer shell of the electromagnet 11 has threads, which are fixed in the corresponding threaded holes of the lower shell 6 by threaded connection;

[0038] The piston extension execution unit includes a spiral push block 5, a piston cover 7, a fixing bolt 8, a piston 12, and a one-way valve 13; the interior of the spiral push block 5 is a cylindrical cavity, and the external spiral spline consists of two sections, the first section is 3 circumferentially uniformly distributed spiral splines, which cooperate with the spiral spline grooves inside the lower shell 6 to realize the spiral motion guidance of the spiral push block 5, and the second section is 3 circumferentially uniformly distributed variable thickness spiral splines, with a total of 3 sections, which contact the piston 12 to realize the extension of the piston 12; the piston cover 7 is spiral, and is provided with three uniformly distributed piston holes and 8 countersunk threaded holes on the piston cover 7. There are three covers 7, which are evenly distributed along the circumference; the upper part of the piston 12 is cylindrical, the lower part is a rectangular parallelepiped structure, and the bottom is an inclined surface, the inclination of which is consistent with the inclination of the variable thickness spiral spline of the spiral push block 5. There are nine pistons 12, and a spring is provided between the piston 12 and the piston cover 7 to achieve the retraction of the piston; there are three one-way valves 13, which are evenly distributed along the circumference, and the outer shell of the one-way valve 13 is provided with a thread, which is fixed in the corresponding threaded hole of the upper shell 2 through a threaded connection; the piston cover 7 is fixed to the lower shell 6 by fixing bolts 8, and the number of the fixing bolts 8 is 24;

[0039] The connection module includes an upper joint 1, an upper shell 2, and a lower shell 6; the outer portion of the lower shell 6 has three circumferentially evenly distributed spiral grooves, each of which has three piston holes, and the inner portion of the lower shell 6 has three circumferentially evenly distributed spiral grooves; the upper joint 1 and the upper shell 2 are connected by a tapered thread, and the upper shell 2 and the lower shell 6 are connected by a tapered thread.

[0040] In this embodiment, the control module is located inside the motor protection housing and has good sealing. Its function is that the MCU controls the driver to realize the rotation of the DC motor and the power on and off of the electromagnet.

[0041] In this embodiment, the motion execution module is the core module of the intelligent straightener for realizing multi-stage variable diameter, including a flow channel control execution unit, a stroke control execution unit, and a piston extension execution unit. The function of the flow channel control execution unit is to control the connection between the flow channel of the flow channel controller 3 and the flow channel of the diverter 4. At this time, the high-pressure drilling fluid enters through the flow channel of the diverter 4, pushing the spiral push block 5 to spirally move, so that the piston 12 extends; the function of the stroke control execution unit is to control the extension of the positioning pin, and the positioning pin slides into the round hole along the U-shaped spiral groove. Different positioning pins make the angle and distance of the spiral movement of the stroke controller 9 different, realizing the function of the straightener under different diameters; the function of the piston extension execution unit is to control the extension of the piston 12. When the piston 12 retracts, since the cavity formed between the diverter 4 and the spiral push block 5 and the lower shell 6 contains drilling fluid, the drilling fluid can flow out through the one-way valve 13 at this time, avoiding the pressure holding phenomenon that makes the piston 12 unable to retract normally.

[0042] In this embodiment, the function of the connection module is to serve as a shell to connect the entire tool together, so as to fully and accurately realize the functions of the control module and the motion execution module.

[0043] In this embodiment, the reset spring 10 is used to reset the spiral push block 5. When the flow channel openings of the flow channel controller 3 and the diverter 4 are staggered, the upper end of the spiral push block 5 is not subjected to the pressure of the high-pressure drilling fluid, and the spiral push block 5 is reset under the action of the reset spring 10.

[0044] In this embodiment, each piston cover 7 is provided with 8 groups of threaded holes, and the piston cover 7 is fixed to the lower housing 6 by screws. At this time, the piston 12 cannot directly rush out of the lower housing 6 when it is extended by force.

[0045] like Figure 3 As shown, a spring is installed between the piston 12 and the piston cover 7. After the spiral push block 5 is reset, the piston 12 will retract under the action of the spring.

[0046] like Figure 5 As shown, the working principle of the intelligent centralizer for realizing multi-stage variable diameter is as follows: the diameter size required for the centralizer is selected, and the intelligent centralizer for realizing multi-stage variable diameter is remotely controlled on the ground, and the electromagnet 11 of the corresponding size is energized, and the motor 19 drives the controller 3 to rotate 60° clockwise. At this time, the flow channel controller 3 and the flow channel of the diverter 4 are connected, and the drilling fluid enters the chamber to squeeze the spiral push block 5. The spiral push block 5 moves in a spiral motion, and the positioning pin slides along the U-shaped spiral groove and reaches the end circular hole to realize stroke control. The radial piston 12 extends to realize the diameter change. When the intelligent centralizer for realizing multi-stage variable diameter finishes working, first the electromagnet 11 is powered off, and the motor 19 drives the flow channel controller 3 to rotate 60° counterclockwise, and the flow channels of the flow channel controller 3 and the diverter 4 are staggered. At this time, the spiral push block 5 is no longer subjected to the pressure of the high-pressure drilling fluid. Under the action of the reset spring 10, the spiral push block 5 is reset, and the positioning pin is also reset accordingly. The radial piston is also reset under the action of the spring.

Claims

1. An intelligent centralizer that realizes multi-stage diameter change, characterized by: The intelligent centralizer for realizing multi-stage diameter change includes a control module, a motion execution module, and a connection module: The control module is located in a protective housing (20) on the motor, and comprises an MCU (21) and a battery pack (22); The motion execution module includes a flow channel control execution unit, a stroke control execution unit, and a piston extension execution unit; The flow channel control execution unit comprises a flow channel controller (3), a flow divider (4), a thrust ball bearing (14), an end cover (15), a transmission shaft (16), a magnetic coupler (17), a motor lower protective shell (18), a motor (19), and a motor upper protective shell (20); the motor lower protective shell (18) and the motor upper protective shell (20) are provided with four evenly distributed fan-shaped cavities, and drilling fluid enters the flow channel controller (3) through the cavities; the motor lower protective shell (18) and the motor upper protective shell (20) are connected by threads; the motor (19) is fixed in the motor upper protective shell (20) by bolts, the magnetic coupler (17) and the transmission shaft (16) are connected by four groups of circumferentially evenly distributed bolts, and the end cover (17) is connected to the motor upper protective shell (20) by four groups of circumferentially evenly distributed bolts; 5) and the flow channel controller (3) are connected by four groups of circumferentially evenly distributed bolts, and the transmission shaft (16) is fixed in the flow channel controller (3). Key slots are provided at both ends of the transmission shaft (16), and circumferential transmission between the transmission shaft (16) and the magnetic coupler (17) and the flow channel controller (3) is achieved through the key connection; three circumferentially evenly distributed radial flow channel holes are provided near the end of the lower shell of the flow channel controller (3), and three flow channel holes corresponding to the flow channel controller (3) are provided inside the flow divider (4), and the flow channel inside the flow divider (4) is directed from radial to axial; a thrust ball bearing (14) is provided between the flow channel controller (3) and the flow divider (4), and the thrust ball bearing (14) is axially positioned through a shoulder inside the upper shell (2); The stroke control execution unit comprises a stroke controller (9), a return spring (10), and an electromagnet (11); the stroke controller (9) is provided with three spiral U-shaped grooves with different spiral heights on the outside, and a circular hole with a depth of 8 mm is provided at the upper end of the spiral U-shaped groove; the return spring (10) is installed at the lower end of the stroke controller (9), and axial positioning is achieved through the shaft shoulder of the stroke controller (9) and the shoulder in the lower shell (6); when the stroke controller (9) moves axially, the return spring (10) is compressed or extended; the spiral push block (5) and the stroke controller (9) are ) are connected by threads to achieve synchronous rotation, the number of the electromagnets (11) is 3, the outer shell of the electromagnet (11) is threaded, and is fixed in the threaded hole of the corresponding lower shell (6) by threaded connection; when the electromagnet (11) is not energized, the positioning pin is in a retracted state, and when the electromagnet (11) is energized, the positioning pin pops out; as the stroke controller (9) spirally moves downward, the positioning pin slides in the U-shaped spiral groove of the stroke controller, and when it reaches the end of the U-shaped spiral groove, the positioning pin is engaged in the circular hole at the end of the U-shaped spiral groove of the stroke controller (9), thereby achieving stroke positioning; The piston extension execution unit comprises a spiral push block (5), a piston cover (7), a fixing bolt (8), a piston (12), and a one-way valve (13); the interior of the spiral push block (5) is a cylindrical cavity, and the external spiral spline consists of two sections, the first section is three spiral splines evenly distributed in the circumference, which cooperate with the spiral spline grooves inside the lower shell (6) to achieve the spiral motion guidance of the spiral push block (5), and the second section is three spiral splines evenly distributed in the circumference with variable thickness, with a total of three sections, which contact the piston (12) to achieve the extension of the piston (12); the piston cover (7) is spiral-shaped, and is provided with three evenly distributed piston holes and eight countersunk threaded holes on the piston cover (7). (7) The number is 3 and they are evenly distributed along the circumference; the upper part of the piston (12) is cylindrical, the lower part is a rectangular parallelepiped structure, and the bottom is an inclined surface, the inclination of which is consistent with the inclination of the variable thickness spiral spline of the spiral push block (5), the number of pistons (12) is 9, and a spring is provided between the piston (12) and the piston cover (7) to achieve the retraction of the piston; the number of the one-way valves (13) is 3 and they are evenly distributed along the circumference, the outer shell of the one-way valve (13) is provided with a thread, and is fixed in the threaded hole of the corresponding upper shell (2) through a threaded connection; the piston cover (7) is fixed to the lower shell (6) by a fixing bolt (8), and the number of the fixing bolts (8) is 24; The connection module comprises an upper joint (1), an upper shell (2), and a lower shell (6); the lower shell (6) has three spiral grooves evenly distributed in the circumferential direction on the outside, each spiral groove has three piston holes inside, and the lower shell (6) has three spiral grooves evenly distributed in the circumferential direction inside; the upper joint (1) and the upper shell (2) are connected via a tapered thread, and the upper shell (2) and the lower shell (6) are connected via a tapered thread.

2. The intelligent centralizer for realizing multi-stage diameter change according to claim 1, characterized in that: The magnetic coupler (17) comprises an outer rotor (1701), a permanent magnet (1702), and an inner rotor (1703); the outer rotor (1701) and the motor shaft are connected by bolts; the outer rotor (1701) and the motor shaft are connected by a key to achieve circumferential transmission; the inner rotor (1703) and the transmission shaft (16) are connected by bolts; the inner rotor (1703) and the transmission shaft (16) are connected by a key to achieve axial positioning.

3. The intelligent centralizer for realizing multi-stage diameter change according to claim 1, characterized in that: O-rings are installed on the flow channel controller (3) and the flow divider (4) to prevent high-pressure drilling fluid from penetrating into the thrust ball bearing (14) and affecting the life of the thrust ball bearing (14).

4. The intelligent centralizer for realizing multi-stage diameter change according to claim 1, characterized in that: The motor (19) is a DC motor. The motor (19) rotates to drive the flow channel of the flow channel controller (3) to communicate with the flow channel of the diverter (4). High-pressure drilling fluid enters through the flow channel opening, pushing the spiral push block (5) to produce a downward spiral motion, pushing the piston (12) to extend; when the piston (12) retracts, the spiral push block (5) moves upward in a spiral motion. At this time, the drilling fluid in the cavity between the spiral push block (5) and the diverter (4) is discharged out of the tool through the one-way valve (13), thereby avoiding the phenomenon of pressure build-up that causes the spiral push block (5) to be unable to reset.

5. The intelligent centralizer for realizing multi-stage diameter change according to claim 1, characterized in that: The U-shaped spiral groove of the spiral push block (5), the spiral spline of the stroke controller (9), and the spiral groove inside the lower housing (6) have the same spiral angle.

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