CN115853419A - A wriggling advancing device for gas hydrate coiled tubing well drilling - Google Patents

Abstract

A peristaltic propulsion device for gas hydrate coiled tubing drilling is presented, comprising a hollow cylindrical body. A peristaltic mechanism, a front gripping mechanism and a rear gripping mechanism, and a first controller for controlling the above mechanisms are installed in the body. Wherein the front and rear gripping mechanisms are configured to alternately engage and disengage the well wall under the control of the first controller. The peristaltic mechanism is configured to extend when the rear gripping mechanism is engaged with the well wall and the forward gripping mechanism is not engaged with the well wall and to retract when the forward gripping mechanism is engaged with the well wall and the rear gripping mechanism is not engaged with the well wall to effect peristaltic movement of the peristaltic propulsion device.

Description

A wriggling advancing device for gas hydrate coiled tubing well drilling

Technical Field

The invention relates to the field of petroleum drilling, in particular to a peristaltic propulsion device for drilling a natural gas hydrate continuous pipe.

Background

The reserves of natural gas hydrates are enormous. According to incomplete statistics, the reserves of the natural gas hydrates are more than twice of the reserves of the traditional oil and gas resources, and the natural gas hydrates are possible to become main alternative energy sources in the future.

Over 90% of the world's natural gas hydrate resources are distributed on the continental shelf seabed, and the occurrence state in the stratum is mainly porous filling, block, vein and the like. The natural gas hydrate is generally buried shallowly, the burial depth of permafrost zone hydrate is generally within a range of hundreds of meters, and the natural gas hydrate in the sea area is generally located within a range of hundreds of meters below the sea bottom.

The conventional deepwater drilling generally needs to drill for thousands of meters at the seabed, and equipment such as a large deepwater semi-submersible drilling platform, a large deepwater drilling ship and the like are mostly used. If the method is applied to the drilling operation of the natural gas hydrate, huge waste is caused. The coiled tubing drilling technology can ensure the reservoir drilling rate, increase the reservoir oil drainage area and improve the development efficiency, and the composite coiled tubing drilling machine has light weight and small occupied area, and the drilling depth capability (up to 3000 m) can meet the requirements of drilling operation of the natural gas hydrate in the sea area. Therefore, the related equipment of the coiled tubing drilling technology can be directly installed on a small and medium-sized drilling ship or a workover ship, and the drilling cost is favorably reduced. Therefore, the coiled tubing drilling technology has wide application prospect in the aspect of sea natural gas hydrate drilling.

Because sea area natural gas hydrate is buried shallowly, and the geology is loose, and the ground cementation nature is poor, lead to horizontal well drilling in-process directional difficulty, and because horizontal well drilling dog leg degree is great, the unable rotation of in-process tubular column of coiled tubing drilling leads to tubular column frictional resistance big, horizontal extension difficulty. The existing continuous pipe tractor or crawler mostly adopts hydraulic drive, has very complex structure and needs to improve the stability,

therefore, a device which has a simple structure and high stability and is suitable for drilling a marine natural gas hydrate coiled tubing is urgently needed, the problem of difficult orientation can be solved, and the horizontal extension capacity of the coiled tubing can be improved.

Disclosure of Invention

In view of the technical problems described above, the present invention aims to provide a peristaltic propulsion device for drilling a natural gas hydrate continuous pipe. The device has a simple structure and can stably realize peristaltic propulsion.

According to the invention, a peristaltic propulsion device for drilling a natural gas hydrate coiled tubing is provided, comprising a hollow cylindrical body. A peristaltic mechanism, a front gripping mechanism and a rear gripping mechanism are mounted in the body, as well as a first controller for controlling the mechanisms. Wherein the front and rear gripping mechanisms are configured to alternately engage and disengage the well wall under control of the first controller. The peristaltic mechanism is configured to extend when the rear gripping mechanism is engaged with the well wall and the front gripping mechanism is not engaged with the well wall and to retract when the front gripping mechanism is engaged with the well wall and the rear gripping mechanism is not engaged with the well wall to effect peristaltic movement of the peristaltic propulsion device.

In one embodiment, the peristaltic mechanism includes a first motor, a first expandable structure, and a first linkage plate fixedly coupled to both the first expandable structure and the front gripping mechanism. The first motor is configured to receive a command sent by the first controller and rotate, so that the first telescopic structure is driven to extend out, and the first connecting plate is driven to move in the body.

In one embodiment, the peristaltic mechanism further includes a second motor, a second telescoping structure, and a second connecting plate fixedly connected to both the second telescoping structure and the rear gripping mechanism. The second motor is configured to receive a command sent by the first controller and rotate, so that the second telescopic structure is driven to extend out, and the second connecting plate is driven to move in the body.

In one embodiment, the apparatus further comprises an inner barrel mounted within the body by a centering block, the first controller, the first motor, the first telescoping structure, and the second motor, the second telescoping structure all mounted within the inner barrel.

In one embodiment, the body and inner barrel are spaced apart and the first and second connection plates are each provided with a through hole for forming a channel for downhole fluid flow.

In one embodiment, the front gripping mechanism includes a front drive unit and a front action unit and the rear gripping mechanism includes a rear drive unit and a rear action unit. The front driving unit and the rear driving unit can output rotation under the control of the first controller, and the front action unit and the rear action unit can radially expand and contract in response to the rotation of the front driving unit and the rear driving unit respectively so as to form engagement or release engagement with the well wall.

In one embodiment, the front drive unit includes a second controller, a third motor, and a first rotating wheel, the second controller configured to receive a signal from the first controller to drive the third motor to rotate and ultimately the first rotating wheel to rotate. The rear driving unit comprises a third controller, a fourth motor and a second rotating wheel, wherein the third controller is configured to receive a signal from the first controller to drive the fourth motor to rotate, and finally drive the second rotating wheel to rotate.

In one embodiment, the front action unit comprises a front gear assembly and a front radial telescopic assembly, the front gear assembly is connected with the first rotating wheel and converts the rotation of the first rotating wheel into the radial telescopic motion of the front radial telescopic assembly, and the front radial telescopic assembly comprises a front anchor claw for clamping the well wall when the front radial telescopic assembly extends out radially. The back action unit includes back gear assembly and the radial flexible subassembly in back, the back gear assembly with the second swiveling wheel is connected, and will the rotation of second swiveling wheel turns into the radial concertina movement of the radial flexible subassembly in back, the radial flexible subassembly in back includes the back fluke, is used for the wall of a well is blocked when the radial flexible subassembly in back radially stretches out.

In one embodiment, the forward and rearward gear assemblies each include a central bevel gear and a driven bevel gear in meshing engagement with the central bevel gear. The front and rear radial telescopic assemblies respectively comprise a lead screw, a nut, a slide rail and a push rod, wherein the slide rail and the push rod are arranged along the radial direction, and the lead screw can rotate under the action of the driven bevel gear, so that the nut slides along the slide rail, and the push rod and a front fluke or a rear fluke arranged at the tail end of the push rod are driven to move in the radial direction.

In one embodiment, the first controller is configured to: actuating the rear gripping mechanism to engage a rear fluke in the rear action unit with the borehole wall; actuating the peristaltic mechanism so as to simultaneously extend the first and second telescoping structures; actuating the front gripping mechanism to actuate so that the front flukes in the front action unit engage the borehole wall; actuating the rear gripping mechanism to release the rear fluke from engagement with the borehole wall; actuating the peristaltic mechanism to cause the first and second collapsible structures to collapse simultaneously; actuating the front gripping mechanism to act to release the front fluke from engagement with the borehole wall.

The invention provides a propelling device for drilling a natural gas hydrate coiled tubing based on a caterpillar-like peristalsis principle. In the drilling process of the directional section and the horizontal section, the peristaltic propulsion device can stabilize the downhole drilling tool assembly and provide powerful mechanical support for a directional deflecting tool, so that the drilling deflecting capability of the shallow soft stratum of the natural gas hydrate in the sea area is improved. Meanwhile, the peristaltic propulsion device can also pressurize the drill bit, improve the well drilling extension capacity of the continuous pipe horizontal well and provide an economic and reliable technical means for drilling and production of the natural gas hydrate. Meanwhile, the peristaltic propulsion device is driven by electricity, and compared with a hydraulic driving mode, the peristaltic propulsion device is simpler in structure, higher in reliability and lower in cost.

Drawings

The invention will now be described with reference to the accompanying drawings.

Fig. 1 schematically shows in cross-section the overall structure of a peristaltic propulsion device for gas hydrate coiled tubing drilling according to the present invention.

Fig. 2A to 2G show the respective courses of action in one working cycle of the peristaltic propulsion device for gas hydrate coiled tubing drilling, respectively.

In the present application, the drawings are schematic, merely illustrative of the principles of the invention, and are not drawn to scale. Throughout the drawings, the same reference numerals are used to designate the same parts or structures.

Detailed Description

The invention is described below with reference to the accompanying drawings. For ease of understanding, in the present application, the direction closer to the wellhead is defined as leading, leading or similar terms, while the direction further away from the wellhead is defined as trailing, trailing or similar terms; meanwhile, the direction along the length of the peristaltic propulsion device is referred to as the longitudinal direction, the axial direction or the like, and the direction perpendicular thereto is referred to as the transverse direction, the radial direction or the like.

Fig. 1 shows the overall structure of a peristaltic propulsion device 100 for gas hydrate coiled tubing drilling according to the present invention. As shown in fig. 1, the peristaltic propulsion device 100 comprises a cylindrical hollow body 1, and a hollow inner cylinder 6 mounted in the body 1. A gap is formed between the inner barrel 6 and the body 1 for the flow of downhole fluids (e.g. drilling fluid) therethrough. The inner cylinder 6 is fixed in the body 1 by a centering block 7, thereby maintaining its centered state in the body 1. In the illustrated embodiment, the centralizing blocks 7 may be fixed to the inner wall of the body 1 by bolts 52.

The first controller 2 is installed in the inner cylinder 6. In the preferred embodiment shown in fig. 1, a first controller 2 is mounted in the central region of the inner drum 6 for receiving ground signals and issuing control commands to control the mechanisms in the peristaltic propulsion device 100. The first controller 2 is a core control unit in the peristaltic propulsion device 100, and the specific functions will be described below

According to the present invention, a peristaltic mechanism 40, a front grip mechanism 41 and a rear grip mechanism 42 are installed in the body 1 (see fig. 2A). Wherein the peristaltic mechanism 40 comprises two sets of components arranged axially symmetrically about the first controller 2. Specifically, in one aspect, as shown in fig. 1, the peristaltic mechanism 40 includes a first battery 3, a first motor 4, a first telescoping structure 5, and a first linkage plate 11 positioned in front of the first controller 2. The first motor 4 is powered by the first battery 3 and is connected to both the first controller 2 and the first telescopic structure 5. Thus, under the control of the command given by the first controller 2, the first motor 4 rotates in the first direction, thereby driving the first telescopic structure 5 to extend. The first connection plate 11 is slidably mounted inside the body 1 and is fixedly connected to the first telescopic structure 5. Thus, when the first telescopic structure 5 is extended, the first connecting plate 11 is moved therewith.

Similarly, on the other hand, the peristaltic mechanism 40 comprises a second battery 8, a second motor 9, a second telescopic structure 10 and a second connection plate 11, located behind the first control 2. A second motor 9 is powered by a second battery 8 and is connected to both the first controller 2 and the second telescopic structure 10. Therefore, under the control of the command given by the first controller 2, the second motor 9 rotates in the second direction, so as to drive the second telescopic structure 10 to extend. A second connection plate 11 is slidably mounted inside the body 1 and is fixedly connected to the second telescopic structure 10. Thus, when the second telescopic structure 10 is extended, the second connecting plate 11 is also moved.

That is, as described above, the peristaltic mechanism 40 is capable of moving forward or backward as a whole under the control of the first controller 2 by a distance equal to the sum of the distances that the first and second extensible structures 5 and 10 each extend.

According to one specific embodiment of the present invention, the first and second telescopic structures 5, 10 may be formed by ball screw structures or piston-link mechanisms.

In addition, the connection plate 11 is provided with a plurality of uniformly arranged through holes 51 along the circumferential direction for allowing the downhole fluid (e.g., drilling fluid) to flow through.

As shown in fig. 1 and 2A, the front grip mechanism 41 includes a front drive unit and a front action unit. The front drive unit comprises a second controller 12, a third battery 13, a third motor 14 and a first rotating wheel 15. The second controller 12 is configured to receive a control command from the first controller 2, and thereby control rotation of the third motor 14. The third motor 14 is powered by the third battery 13 and can drive the first rotating wheel 15 to rotate. The entire front drive unit is mounted in the slide tube 17 and is fixedly connected to the first connecting plate 11 so as to be movable forward or backward in accordance with the forward or backward movement of the first connecting plate 11.

The front action unit is connected to the front drive unit and comprises a front gear assembly connected to the rotary wheel 15 and a front radial telescopic assembly connected to the front gear assembly. Specifically, the front gear assembly includes a first connecting rod 16 connected to the first rotating wheel 15, a first driving bevel gear 18 mounted on the first connecting rod 16, and two first driven bevel gears 19a and 19b engaged with the first driving bevel gear 18. The front radial retraction assembly comprises two sets of diametrically opposed elements which are connected to the first driven bevel gears 19a and 19b respectively. Specifically, each set includes a lead screw 20, a nut 21, a ram 22, a slide rail 23, and a front fluke 24. Taking the upper set in fig. 1 as an example, the screw 20 is connected to the first driven bevel gear 19a, so that when the first driven bevel gear 19a rotates, the screw also rotates, so as to push the nut 21 to move along the slide rail 23, and further drive the push rod 22 to move. Thus, the front fluke 24 fixed at the tip of the jack 22 can be extended out of the body 1 in the radial direction or retracted into the interior of the body 1.

As shown in fig. 1 and 2A, the rear grip mechanism 42 includes a rear drive unit and a rear action unit. The rear drive unit comprises a third controller 25, a fourth battery 26, a fourth motor 27 and a second swivel wheel 28. The third controller 25 is configured to receive a control command from the first controller 2, and thereby control the rotation of the fourth motor 27. A fourth motor 27 is powered by a fourth battery 26 and can drive a second rotary wheel 28 for rotation. The entire rear drive unit is mounted in the slide cylinder 17 and is fixedly connected to the second connecting plate 11 so as to be movable rearward or rearward with the rearward or rearward movement of the second connecting plate 11.

The rear action unit is connected to the rear drive unit and comprises a rear gear assembly connected to the swivel wheel 28 and a rear radial telescopic assembly connected to the rear gear assembly. Specifically, the rear gear assembly includes a second connecting rod 29 connected to the second rotating wheel 28, a second driving bevel gear 30 mounted on the second connecting rod 29, and two second driven bevel gears 31a and 31b engaged with the second driving bevel gear 30. The rear radial expansion and contraction assembly comprises two sets of diametrically opposed members connected to the second driven bevel gears 31a and 31b, respectively. Specifically, each set includes a lead screw 32, a nut 33, a ram 34, a slide rail 35, and a rear fluke 36. Taking the upper set in fig. 1 as an example, the screw rod 32 is connected to the second driven bevel gear 31a, so that when the second driven bevel gear 31a rotates, the screw rod can also rotate, so as to push the nut 32 to move along the slide rail 35, and further drive the push rod 34 to move. In this way, the rear fluke 36 fixed at the end of the carrier rod 34 can be extended radially out of the body 1 or retracted into the interior of the body 1.

The respective courses of action within one working cycle of the peristaltic propulsion device 100 according to the present invention are described below with reference to fig. 2A to 2G.

As shown in FIG. 2A, the peristaltic propulsion device 100 is in an initial state wherein the peristaltic mechanism 40 is in place. At this time, front fluke 24 and rear fluke 36 are both in an initial state, i.e. retracted radially inside body 1.

As shown in fig. 2B, when the first controller 2 receives a propulsion signal transmitted from the ground, it gives a command to the third controller 25 of the rear gripping mechanism 42. At this time, the third controller 25 controls the fourth motor 27 to rotate, thereby rotating the second driving bevel gear 30 of the rear acting unit via the second rotation wheel 28 and the second connection rod 29. Under the action of gear mesh transmission, the second driven bevel gear also rotates, so that the screw rod 32 is driven to rotate. Thus, the nut 32 slides outwardly along the slide rails 35, which in turn moves the carrier rod 34 radially outwardly. At this point, rear fluke 36 extends radially outward, thereby seizing the borehole wall.

The first controller 2 then controls the extension of the peristaltic mechanism 40 as shown in FIG. 2C. Specifically, the first controller 2 controls the first motor 4 and the second motor 9 to rotate in opposite directions, so as to drive the first telescopic structure 5 and the second telescopic structure 9 to extend simultaneously. Since the rear fluke 36 is now stuck against the borehole wall, the front portion of the propulsion apparatus 100 (i.e. the portion where the front gripping mechanism 41 is located) will move forward a distance equal to the sum of the distances the first 5 and second 10 telescoping structures extend.

As shown in fig. 2D, the first controller 2 then issues a command to the second controller 12 of the forward gripping mechanism 41. At this time, the second controller 12 controls the third motor 14 to rotate, thereby rotating the first driving bevel gear 18 of the front action unit via the first rotation wheel 15 and the first connection rod 16. Under the action of the gear mesh transmission, the first driven bevel gear also rotates, so that the screw rod 20 is driven to rotate. In this way, the nut 21 slides outwards along the slide rail 23, which in turn drives the ram 22 radially outwards. At this point, the front fluke 24 is extended radially outward, thereby seizing the borehole wall.

As shown in fig. 2E, first controller 2 issues an instruction to third controller 25 of rear gripping mechanism 42 to perform a reverse series of actions to those described with respect to fig. 2B. At this point the rear fluke 36 is retracted inwardly into the body 1 so that it no longer grips the borehole wall.

As shown in fig. 2F, the first controller 2 then controls the peristaltic mechanism 40 to contract, and in particular, the first controller 2 controls the first motor 4 and the second motor 9 to each rotate in the opposite direction as described with respect to fig. 2C, thereby causing the first and second expandable structures 5 and 9 to contract simultaneously. Since front fluke 24 is now stuck to the borehole wall and rear fluke 36 is no longer stuck, the rear portion of propulsion device 100 (i.e., the portion where rear gripping mechanism 42 is located) will also move forward the same distance that the front portion of propulsion device 100 moved.

As shown in fig. 2G, the first controller 2 issues a command to the second controller 12 of the forward gripping mechanism 41 to perform a reverse series of actions to those described with respect to fig. 2D. At this point, the front fluke 24 is retracted inwardly into the body 1 so that it no longer grips the borehole wall.

As can be seen from a comparison of fig. 2A and 2G, the propulsion device 100 as a whole has moved forward by a distance equal to the sum of the respective extension distances of the first 5 and second 10 collapsible structures. Thus, the peristaltic propulsion device 100 for gas hydrate coiled tubing drilling according to the present invention completes one cycle of forward motion, advancing "peristaltic" from the position shown in fig. 2A to the position shown in fig. 2G. In one embodiment, one step distance of the downhole peristaltic 100 may be set to 2m.

From the above, when the front fluke 26 and/or the rear fluke 36 grips the borehole wall, the drilling fluid can still flow normally via the annulus between the inner barrel 6 and the body 1 and the through holes 51 in the first and second connection plates 11, without affecting the function thereof.

It will be readily appreciated that if the peristaltic propulsion device 100 is required to creep in the rearward direction, the series of actions described above may be performed again in reverse order.

The invention provides a propelling device for drilling a natural gas hydrate coiled tubing based on a caterpillar-like peristalsis principle. In the drilling process of the directional section and the horizontal section, the peristaltic propulsion device can stabilize the underground drilling tool assembly and provide powerful mechanical support for a directional deflecting tool, so that the drilling deflecting capability of a shallow soft stratum of the natural gas hydrate in the sea area is improved. Meanwhile, the peristaltic propulsion device can also pressurize the drill bit, improve the well drilling extension capacity of the continuous pipe horizontal well and provide an economic and reliable technical means for drilling and production of the natural gas hydrate. Meanwhile, the peristaltic propulsion device is driven by electricity, and compared with a hydraulic driving mode, the peristaltic propulsion device is simpler in structure, higher in reliability and lower in cost.

It should be noted that the positions of the respective motors, batteries, and the like shown in the drawings are schematic, and they may be set at appropriate positions according to the needs of the specific situation.

Finally, it should be noted that the above-mentioned embodiments are only preferred embodiments of the present invention, and do not limit the present invention in any way. Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described in the foregoing examples, or that equivalents may be substituted for elements thereof. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A peristaltic propulsion device (100) for drilling gas hydrate continuous tubes, comprising a hollow cylindrical body (1), in said body (1) there are mounted a peristaltic mechanism (40), a front gripping mechanism (41) and a rear gripping mechanism (42), and a first controller (2) for controlling the above mechanisms,

wherein the front gripping mechanism (41) and the rear gripping mechanism (42) are configured to alternately engage and disengage the well wall under the control of the first controller (2),

the peristaltic mechanism (40) is configured to extend when the rear gripping mechanism (42) is engaged with the well wall while the front gripping mechanism (41) is not engaged with the well wall and to retract when the front gripping mechanism (41) is engaged with the well wall while the rear gripping mechanism (42) is not engaged with the well wall to effect peristaltic movement of the peristaltic propulsion device (100).

2. Peristaltic propulsion device (100) according to claim 1, characterized in that said peristaltic mechanism (40) comprises a first motor (4), a first telescopic structure (5), and a first connection plate (11) fixedly connected to both said first telescopic structure (5) and said front gripping means (41),

the first motor (4) is configured to receive a command sent by the first controller (2) and rotate, so that the first telescopic structure (5) is driven to extend, and the first connecting plate (11) is driven to move in the body (1).

3. Peristaltic propulsion device (100) according to claim 2, characterized in that said peristaltic mechanism (40) further comprises a second motor (9), a second telescopic structure (10), and a second connection plate (11) fixedly connected to both said second telescopic structure (10) and said rear gripping means (42),

the second motor (9) is configured to receive a command sent by the first controller (2) and rotate, so as to drive the second telescopic structure (10) to extend out, and further drive the second connecting plate (11) to move in the body (1).

4. A peristaltic propulsion device (100) according to claim 3, further comprising an inner drum (6) mounted inside said body (1) through a centering block (7), said first controller (2), first motor (4), first telescopic structure (5) and second motor (9), second telescopic structure (10) all being mounted in said inner drum (6).

5. A peristaltic propulsion device (100) according to claim 4, wherein said body (1) and inner cylinder (6) are arranged spaced apart and said first and second connection plates are each provided with a through hole (11) for forming a passage for the flow of downhole fluids.

6. Peristaltic propulsion device (100) according to any one of claims 1 to 5, characterised in that said front gripping mechanism (41) comprises a front drive unit and a front action unit, said rear gripping mechanism (42) comprises a rear drive unit and a rear action unit,

wherein the front and rear drive units are each capable of outputting a rotation under the control of the first controller (2), and the front and rear action units are radially extendable and retractable in response to rotation of the front and rear drive units, respectively, to engage or disengage the well wall.

7. Peristaltic propulsion device (100) according to claim 6, characterized in that said front drive unit comprises a second controller (12), a third motor (14) and a first rotary wheel (15), said second controller (12) being configured to receive signals from said first controller (2) to drive said third motor (14) in rotation and, finally, to drive said first rotary wheel (15) in rotation,

the rear drive unit comprises a third controller (25), a fourth motor (27) and a second rotary wheel (28), the third controller (25) is configured to receive a signal from the first controller (2) to drive the fourth motor (27) to rotate and finally drive the second rotary wheel (28) to rotate.

8. Peristaltic propulsion device (100) according to claim 7, characterised in that said front action unit comprises a front gear assembly and a front radial telescopic assembly, said front gear assembly being coupled to said first rotating wheel (15) and translating the rotation of said first rotating wheel (15) into a radial telescopic movement of said front radial telescopic assembly, said front radial telescopic assembly comprising a front fluke (24) for gripping the wall of the well when said front radial telescopic assembly is radially extended,

back action unit includes back gear assembly and the radial flexible subassembly in back, the back gear assembly with second swiveling wheel (28) are connected, and will the rotation of second swiveling wheel (28) turns into the radial concertina movement of the radial flexible subassembly in back, the radial flexible subassembly in back includes back fluke (24), is used for the wall of a well is blocked when the radial flexible subassembly in back radially stretches out.

9. A peristaltic propulsion device (100) according to claim 8, wherein said front and rear gear assemblies each comprise a central bevel gear, and a driven bevel gear meshing with said central bevel gear,

the front and rear radial telescopic assemblies respectively comprise a lead screw, a nut, a slide rail and a push rod, wherein the slide rail and the push rod are arranged along the radial direction, and the lead screw can rotate under the action of the driven bevel gear, so that the nut slides along the slide rail, and the push rod and a front fluke or a rear fluke arranged at the tail end of the push rod are driven to move in the radial direction.

10. The peristaltic propulsion device (100) according to claim 8, characterized in that said first controller (2) is configured to:

actuating the rear gripping mechanism to engage the rear fluke in the rear action unit with the borehole wall;

actuating the peristaltic mechanism so that the first and second telescoping structures extend simultaneously;

actuating the front gripping mechanism to actuate so that the front flukes in the front action unit engage the borehole wall;

actuating the rear gripping mechanism to release the rear fluke from engagement with the borehole wall;

actuating the peristaltic mechanism to cause simultaneous contraction of the first and second collapsible structures;

actuating the front gripping mechanism to act to release the front fluke from engagement with the borehole wall.

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