CN115434643A

CN115434643A - Drilling device

Info

Publication number: CN115434643A
Application number: CN202211223713.5A
Authority: CN
Inventors: 张向东; 丁虹达; 胡国航; 李佳泽; 郑春宇; 张宇; 张善峰
Original assignee: Liaoning Technical University
Current assignee: Liaoning Technical University
Priority date: 2022-10-08
Filing date: 2022-10-08
Publication date: 2022-12-06

Abstract

The invention belongs to the technical field of drilling equipment, in particular to a drilling device, aiming at the problem that the existing drilling device has poor capacity of grabbing a drilled core column and even causes empty fetching, the invention provides the following scheme, which comprises a drilling machine tower consisting of four vertical H-shaped steels, wherein the middle of the drilling machine tower is connected with two balance sliding blocks in a sliding manner, a same horizontally arranged counterweight bearing seat is fixed between the two balance sliding blocks, a propelling mechanism is arranged in the middle of the counterweight bearing seat, the propelling mechanism comprises a gear barrel which is rotatably connected in the middle of the counterweight bearing seat, and the bottom end of the gear barrel is fixed with a fixed ring piece through a bolt. According to the invention, the drilled core column is bitten and pinched at the position close to the drill bit, and then the drilled core and the sampling rod can be pulled out together, so that the sampling rod is prevented from being pulled out and the rock-soil column at the drilling position is still in the original position.

Description

Drilling device

Technical Field

The invention relates to the technical field of drilling equipment, in particular to a drilling device.

Background

The geotechnical engineering investigation is part of land investigation, and refers to the activities of finding out, analyzing and evaluating geological and environmental characteristics of a construction site and geotechnical engineering conditions and compiling investigation files according to the requirements of construction engineering. Exploration and soil sample collection are one of the main contents of geotechnical engineering investigation.

In the process of scientific ultrasonic well drilling, firstly, how to efficiently drill in a large-diameter well and completely grab a rock sample is faced, in the traditional scientific drilling, a large-diameter well section is firstly drilled into a small well by coring, and then a reamer bit is used for drilling again to enlarge the well to a designed well diameter, so that the problems of hole wall collapse, block falling and drill clamping, uneven stress fracture of a drill column and the like are easily caused by the mode, and therefore a novel drilling device with high strength, capable of directly drilling and capable of improving the rock core grabbing capacity is needed.

Disclosure of Invention

The invention provides a drilling device, aiming at solving the problems that the existing drilling device has poor capacity of grabbing a drilled core column and even causes the phenomenon of empty taking.

In order to achieve the purpose, the invention adopts the following technical scheme: the utility model provides a drilling rig, includes the rig tower that comprises four vertical H shaped steel, and the centre sliding connection of rig tower has two balanced sliders, is fixed with the counter weight bearing frame that same level set up between two balanced sliders, and is provided with advancing mechanism in the centre of counter weight bearing frame, advancing mechanism is including rotating the gear barrel of connecting in the middle of the counter weight bearing frame, and the bottom of gear barrel has fixed ring spare through the bolt fastening, and the centre of fixed ring spare is fixed with can pivoted impel square pipe, and the bottom joint that impels square pipe has a plurality of intermediate levers, and the bottom joint of intermediate lever has a thief rod, and the bottom joint of thief rod has the drill bit, the circumference inner wall of drill bit is opened has three hidden grooves that are central symmetric distribution, and all rotates near the bottom in the three hidden groove and is connected with the stopping block, and all is fixed with reset spring between the one side that the stopping block is close to the tank bottom and the tank bottom.

The invention is further characterized in that two bases are fixed at the bottom of the drilling machine tower, anti-collapse foundations are arranged on the two bases, and a level gauge is arranged on the upper surface of each base, so that straight line posture drilling is guaranteed in the drilling process, effective transmission of middle rod force is effectively protected, and rod breakage caused by uneven stress of the middle rod is avoided.

The drilling machine tower is further provided with a cross beam frame fixed at the top end, a rope winder is fixed in the middle of the cross beam frame, a pull rope is arranged at the output end of the rope winder, and a drilling force detection mechanism is arranged between the bottom end of the pull rope and the counterweight bearing seat.

The drilling force detection mechanism comprises an arched suspension rod fixed between the upper surfaces of two balance sliding blocks, a tension spring is fixed in the middle of the top end of the arched suspension rod, a cross rod is fixed at the top end of the tension spring, the top end of the cross rod is fixed at the end of a pull rope, sliding holes are formed in the upper surface of the cross rod close to two ends, guide rods with the diameter smaller than that of the sliding holes are inserted into the sliding holes, the sliding rings are clamped on the upper side and the lower side of the cross rod on the outer wall of one guide rod, pressure sensors are fixed on the opposite sides of the two sliding rings, the fluctuation alarm range of the drilling force can be adjusted by controlling the distance between the two sliding rings, once the top pressure sensor gives an alarm, the drill bit is blocked, the drilling speed needs to be reduced at the moment, the bottom pressure sensor gives an alarm, and the fact that the encountered low geological density is possibly a liquid layer or an oil-gas layer.

The invention is further arranged in that the propulsion mechanism comprises four rows of tapered roller bearings embedded in a counterweight bearing seat, the whole gear barrel consists of a concentric cylindrical pipe and a fluted disc, the cylindrical pipe is fixed in an inner ring of the four rows of tapered roller bearings, a motor mounting position is arranged on the lower surface of the counterweight bearing seat close to the circumferential edge of the fluted disc, a driving motor is clamped in the motor mounting position, a driving gear is fixed at the top end of an output shaft of the driving motor, and the driving gear is meshed with the fluted disc on the gear barrel; the fixed ring piece is fixed on the lower surface of the fluted disc through bolts, an annular groove is formed in the upper surface of the fixed ring piece, four clamping blocks which are distributed in a central symmetry mode are arranged on the inner circumferential wall of the fixed ring piece, four groups of self-locking screw holes are formed in the outer circumferential wall of the fixed ring piece, four self-locking screw rods are in threaded connection with the four groups of self-locking screw holes, the end portions of the self-locking screw rods abut against the surfaces of the clamping blocks, straight rods are fixed on one sides, away from the central point, of the four clamping blocks, the clamping blocks extend along the radial direction, the pushing square tube is clamped among the four clamping blocks, abutting nuts are in threaded connection with one ends, close to the clamping blocks, of the outer circumferential wall of each self-locking screw rod, the pushing square tube can be tightly fixed in the pushing mechanism through the four self-locking screw rods and the clamping blocks, and replacement convenience is improved.

The invention further provides that a plurality of annular oil grooves distributed at equal intervals are formed in the circumferential inner wall of the sampling rod, the cross sections of the annular oil grooves are of right-angled triangle structures, lubricating oil is coated in each layer of annular oil groove in the sampling rod before the sampling rod is drilled, the drilling process can be smoother, the probability of core fracture is reduced, and the grabbing effect of the sampling rod can be improved.

The invention is further arranged in that the bore diameter of the inner bore of the drill bit is 1-1.1 times of the inner diameter of the sampling rod, so that the drilled core can directly enter the sampling rod and has certain expansion extrusion force, the core can be grabbed conveniently, and the structure of the core is not damaged.

The drill bit is further provided with four convex anti-torsion ribs fixed on the circumferential outer wall of the drill bit close to the top end, a large-diameter flaring sleeve is reserved at the bottom end of the sampling rod, a notch matched with the anti-torsion ribs is formed in the circumferential inner wall of the flaring sleeve, a fastening screw hole penetrating through the notch is formed in the circumferential outer wall of the flaring sleeve, a locking bolt is screwed in the fastening screw hole, a pin control matched with the locking bolt is reserved on the side surface of the anti-torsion ribs, and therefore the replacement convenience of the drill bit and the fastening anti-falling effect after installation can be improved.

The invention is further arranged in that three L-shaped anti-drop grooves which are distributed in a centrosymmetric manner are formed in the circumferential outer wall of the sampling rod close to the top end, three L-shaped extension blocks which are matched with the L-shaped anti-drop grooves are reserved at the bottom end of the middle rod, and the extension direction of the L-shaped anti-drop grooves is matched with the rotation direction of the drill bit, so that the drill bit cannot be dropped during drilling.

The invention is further arranged in that spring grooves are formed in the top ends of the sampling rod and the middle rod and are positioned below the L-shaped anti-falling grooves, locking sleeves are connected to the spring grooves in a sliding mode, protruding blocks extending into the spring grooves are reserved on the inner walls of the locking sleeves, and compression springs are fixed on the lower surfaces of the protruding blocks.

To sum up, the beneficial effect in this scheme is:

1. according to the drilling device, the three retaining blocks hinged inside the drill bit are arranged, so that the retaining blocks can be hidden in a blind groove due to the effect of centrifugal force in the drilling process of high-speed rotation, when a drilled core needs to be taken out when the drilling is stopped rotating after the drilling is finished, the three retaining blocks are rapidly popped out, the drilled core column is bitten and pinched close to the drill bit, then the drilled core can be pulled out together with the sampling rod, and the sampling rod is prevented from being pulled out and the drilled rock-soil column is still in the original position;

2. the drilling device can monitor the resistance in the drilling process in real time through the arrangement of the drilling force detection mechanism, and then timely perform corresponding treatment such as reduction of down force or replacement of a drill bit with better hardness;

3. this kind of drilling equipment, through the setting of lock sleeve, can accomplish after the butt joint at two middle poles from top to bottom, with the clearance department between the three L shape extension piece of lock sleeve disect insertion to two middle poles form relative rotation about preventing, improve the auto-lock effect.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a schematic front view of the present invention;

FIG. 3 is an exploded view of the propulsion mechanism of the present invention;

FIG. 4 is a schematic view of the structure of the drilling force detecting mechanism according to the present invention;

FIG. 5 is a schematic view of the structure of the intermediate shaft of the present invention

FIG. 6 is a schematic view of the sample rod of the present invention in the configuration of docking;

FIG. 7 is a schematic view of an exploded structure of a thief rod of the present invention;

FIG. 8 is a schematic view of a half-section of a sampling rod according to the present invention.

In the figure: 1. a driller tower; 2. a counterweight bearing seat; 3. an arcuate boom; 4. a rope winder; 5. a drilling force detection mechanism; 51. a cross bar; 52. a tension spring; 53. a guide rod; 54. a slip ring; 55. a pressure sensor; 6. a fixed ring member; 7. an intermediate lever; 8. a feeding rail; 9. a clamping rod; 10. a drill bit; 11. a sampling rod; 12. a machine base; 13. a balancing slide block; 14. a gear barrel; 15. a drive motor; 16. a clamping block; 17. a self-locking screw;

18. pushing the square tube; 19. a motor mounting position; 20. an L-shaped anti-drop groove; 21. a locking sleeve;

22. a spring slot; 23. an L-shaped extension block; 24. flaring the sleeve; 25. anti-twisting ribs;

26. fastening screw holes; 27. a backstop block; 28. a return spring; 29. a hidden groove; 30. an annular oil groove.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

Example 1

Referring to fig. 1-8, a drilling device comprises a drilling machine tower 1 composed of four vertical H-shaped steels, wherein the middle of the drilling machine tower 1 is slidably connected with two balance sliders 13, a balance weight bearing seat 2 horizontally arranged is fixed between the two balance sliders 13, a propulsion mechanism is arranged in the middle of the balance weight bearing seat 2, the propulsion mechanism comprises a gear barrel 14 rotatably connected in the middle of the balance weight bearing seat 2, a fixed ring part 6 is fixed at the bottom end of the gear barrel 14 through a bolt, a propulsion square pipe 18 capable of rotating is fixed in the middle of the fixed ring part 6, a plurality of middle rods 7 are clamped at the bottom end of the propulsion square pipe 18, a sampling rod 11 is clamped at the bottom end of each middle rod 7, a drill bit 10 is clamped at the bottom end of the sampling rod 11, three blind grooves 29 symmetrically distributed in the center are formed in the inner wall of the circumference of the drill bit 10, a backstop block 27 is rotatably connected to the bottom end of each blind groove 29, and a reset spring 28 is fixed between the side of the backstop block 27 close to the bottom of the groove; articulate the inside three stopping block 27 at drill bit 10 through the setting, can hide stopping block 27 in the blind groove 29 because of the effect of centrifugal force at the high-speed rotatory probing in-process, when need take out the rock core of getting when the probing is finished the stall, three stopping block 27 pops out fast, be close to drill bit 10 position to the rock core post after getting and sting and inlay, later can drag out the rock core of getting together with sample rod 11 together, prevent that sample rod 11 from being dragged out and the rock soil post of getting the position still stands in the original position.

Referring to fig. 1-2, two bases 12 are fixed at the bottom of a drilling machine tower 1, the two bases 12 are provided with anti-collapse foundations, the upper surface of the base 12 is provided with a level gauge, the side surface of the drilling machine tower 1 is provided with two feeding rails 8 with opposite openings, clamping rods 9 are connected between the two feeding rails 8 in a sliding manner, and a spare intermediate rod 7 is connected between the two clamping rods 9 in a sliding manner; make to add intermediate lever 7 more convenient, can guarantee to creep into the posture that the in-process keeps the straight line all the time and creep into moreover, the effective transmission of 7 power of effectual protection intermediate lever and protection intermediate lever 7 can not lead to the pole breakage because of the atress inequality.

Referring to fig. 2, the top of drilling machine tower 1 is fixed with the crossbeam frame, and the centre of crossbeam frame is fixed with ropewinder 4, and ropewinder 4's output is provided with the stay cord, is provided with drilling power detection mechanism 5 between the bottom of stay cord and the counter weight bearing frame 2, can monitor the resistance size of drilling process in real time through the setting of drilling power detection mechanism, then in time make corresponding processing if reduce the push-down force or change better drill bit of hardness etc..

Referring to fig. 4, the drilling force detection mechanism 5 includes an arched boom 3 fixed between the upper surfaces of two balance sliders 13, a tension spring 52 is fixed in the middle of the top end of the arched boom 3, a cross rod 51 is fixed at the top end of the tension spring 52, the top end of the cross rod 51 is fixed at the end of a pull rope, slide holes are formed in the upper surface of the cross rod 51 near to the two ends, guide rods 53 with a diameter smaller than that of the slide holes are inserted into the slide holes, slide rings 54 are clamped on the upper and lower sides of the cross rod 51 on the outer wall of one of the guide rods 53, pressure sensors 55 are fixed on the opposite sides of the two slide rings 54, the fluctuation alarm range of the drilling force can be adjusted by controlling the distance between the two slide rings 54, once the top pressure sensor 55 gives an alarm, it indicates that the drilling of the drill bit 10 is blocked, at this time, the drilling speed needs to be reduced, and the bottom pressure sensor 55 gives an alarm, which indicates that the encountered geological density is less and may be a liquid layer or an oil-gas layer.

Referring to fig. 3, the propulsion mechanism includes four rows of tapered roller bearings embedded in the counterweight bearing seat 2, the whole gear barrel 14 is composed of a concentric cylindrical tube and a fluted disc, the cylindrical tube is fixed in the inner ring of the four rows of tapered roller bearings, a motor mounting position 19 is arranged on the lower surface of the counterweight bearing seat 2 near the circumferential edge of the fluted disc, a driving motor 15 is clamped in the motor mounting position 19, a driving gear is fixed at the top end of an output shaft of the driving motor 15, and the driving gear is meshed with the fluted disc on the gear barrel 14; the fixed ring piece 6 is fixed on the lower surface of the fluted disc through bolts, an annular groove is formed in the upper surface of the fixed ring piece 6, four clamping blocks 16 which are distributed in a central symmetry mode are arranged on the inner circumferential wall of the fixed ring piece 6, four groups of self-locking screw holes are formed in the outer circumferential wall of the fixed ring piece 6, four self-locking screw rods 17 are connected to the four groups of self-locking screw holes in a threaded mode, the end portions of the self-locking screw rods 17 abut against the surfaces of the clamping blocks 16, straight rods are fixed to one sides, far away from a central point, of the four clamping blocks 16, the clamping blocks 16 are ensured to extend along the radial direction, the pushing square pipe 18 is clamped among the four clamping blocks 16, abutting nuts are connected to one ends, close to the clamping blocks 16, of the outer circumferential wall of the self-locking screw rods 17, of the clamping blocks 16, the pushing square pipe 18 can be tightly fixed in the pushing mechanism, and convenience of replacement is improved.

Referring to fig. 8, the circumference inner wall of thief rod 11 is opened has a plurality of equidistant annular oil grooves 30 that distribute, and the cross-section of annular oil groove 30 is the right angled triangle structure, with scribbling lubricating oil in 11 inside each layer of annular oil grooves 30 of thief rod before boring down, can let the drilling process more smooth and easy, reduces the cracked probability of rock core, can also improve 11 snatching effects of thief rod.

In the invention, the bore diameter of the inner bore of the drill bit 10 is 1-1.1 times of the inner diameter of the sampling rod 11, so that the drilled core can directly enter the sampling rod 11 and has certain expansion extrusion force, which is beneficial to grabbing the core and not damaging the core structure.

Referring to fig. 7-8, four protruding anti-twisting ribs 25 are fixed on the circumferential outer wall of the drill bit 10 near the top end, a large-diameter flared sleeve 24 is reserved at the bottom end of the sampling rod 11, a notch matched with the anti-twisting ribs 25 is formed in the circumferential inner wall of the flared sleeve 24, a fastening screw hole 26 penetrating through the notch is formed in the circumferential outer wall of the flared sleeve 24, a locking bolt is screwed in the fastening screw hole 26, a pin control matched with the locking bolt is reserved on the side surface of the anti-twisting ribs 25, and therefore replacement convenience of the drill bit 10 and fastening anti-falling effects after installation can be improved.

Referring to fig. 5, three L-shaped anti-drop grooves 20 are formed in the outer circumferential wall of the sampling rod 11 near the top end, the three L-shaped extension blocks 23 are reserved at the bottom end of the middle rod 7, the extension direction of each L-shaped anti-drop groove 20 is matched with the rotation direction of the drill bit 10, and the drill bit 10 cannot be dropped when drilling.

Referring to fig. 3, spring grooves 22 are formed in the positions, located below the L-shaped anti-falling grooves 20, of the top ends of the sampling rod 11 and the intermediate rod 7, locking sleeves 21 are connected to the positions, located in the spring grooves 22, of the spring grooves 22 in a sliding mode, protruding blocks extending into the spring grooves 22 are reserved on the inner walls of the locking sleeves 21, compression springs are fixed to the lower surfaces of the protruding blocks, the locking sleeves 21 can be directly inserted into gaps between the three L-shaped extending blocks 23 after the upper intermediate rod 7 and the lower intermediate rod 7 are butted through the locking sleeves 21, so that the upper intermediate rod 7 and the lower intermediate rod 7 are prevented from rotating relatively, and the self-locking effect is improved.

When the device is used, firstly, the counterweight bearing seat 2 fixed on the drilling force detection mechanism 5 is lifted to the highest position through the rope winder 4, and the propulsion square pipe 18 is fixed in the fixed ring piece 6 in the propulsion mechanism in advance; then, the sampling rod 11 provided with the drill bit 10 is clamped in the pushing square tube 18, the rope winder 4 can be started slowly to start to slowly lower the pull rope, meanwhile, the driving motor 15 is started again to enable the drill bit 10 to rotate at a high speed, and drilling is started under the action of the counterweight bearing pedestal 2; adding the intermediate rod 7 until the sampling rod 11 is completely drilled into the ground; through setting up the three stopping block 27 that articulates in drill bit 10 inside, hide stopping block 27 in the hidden groove 29 because of the effect of centrifugal force at the high-speed rotatory probing in-process, when waiting to bore the completion stop rotating the time need take out the rock core of getting, three stopping block 27 pops out fast, close to drill bit 10 position to the rock core post after getting and sting and nip, later can be pulled out the rock core of getting together with thief rod 11, prevent that thief rod 11 from being pulled out and the rock-soil post of getting the position still stands in the original position.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.

Claims

1. The utility model provides a drilling rig, includes driller tower (1) that constitutes by four vertical H shaped steel, and the centre sliding connection of driller tower (1) has two balanced slider (13), is fixed with counter weight bearing frame (2) that same level set up between two balanced slider (13), and is provided with advancing mechanism in the centre of counter weight bearing frame (2), its characterized in that, advancing mechanism is including rotating gear barrel (14) of connecting in the middle of counter weight bearing frame (2), and the bottom of gear barrel (14) is fixed with fixed ring spare (6) through the bolt, and the centre of fixed ring spare (6) is fixed with can pivoted propulsion side pipe (18), and the bottom joint of propulsion side pipe (18) has a plurality of intermediate lever (7), and the bottom joint of intermediate lever (7) has thief rod (11), and the bottom joint of thief rod (11) has drill bit (10), the circumference inner wall of drill bit (10) is opened has three camera obscura (29) that are central symmetry distribution, and is close to the bottom and all rotates stopping block (27) near the bottom in three camera obscura (29), and all have reset spring (28) between one side of fixed tank bottom and the fixed tank bottom.

2. A drilling rig according to claim 1, characterized in that two bases (12) are fixed to the bottom of the drilling tower (1), that the two bases (12) are provided with a collapse-proof foundation, that the upper surface of the base (12) is provided with a level, that the sides of the drilling tower (1) are provided with two feeding rails (8) with opposite openings, that between the two feeding rails (8) there are slidably connected clamping rods (9), and that the spare intermediate rod (7) is slidably connected between the two clamping rods (9).

3. A drilling rig according to claim 1, characterized in that a beam frame is fixed to the top end of the drilling tower (1), a rope winder (4) is fixed to the middle of the beam frame, the output end of the rope winder (4) is provided with a pull rope, and a drilling force detection mechanism (5) is arranged between the bottom end of the pull rope and the counterweight bearing block (2).

4. A drilling device according to claim 3, wherein the drilling force detection mechanism (5) comprises an arched suspension rod (3) fixed between the upper surfaces of the two balance sliding blocks (13), a tension spring (52) is fixed in the middle of the top end of the arched suspension rod (3), a cross rod (51) is fixed at the top end of the tension spring (52), the top end of the cross rod (51) is fixed at the end of the pulling rope, sliding holes are formed in the upper surface of the cross rod (51) close to the two ends, guide rods (53) with the diameter smaller than the sliding holes are inserted into the sliding holes, the sliding rings (54) are clamped on the upper and lower sides of the cross rod (51) on the outer wall of one of the guide rods (53), and a pressure sensor (55) is fixed on the opposite side of each of the two sliding rings (54).

5. The drilling device as claimed in claim 1, wherein the propulsion mechanism comprises four rows of tapered roller bearings embedded in a counterweight bearing seat (2), the whole gear barrel (14) is composed of a concentric cylindrical pipe and a fluted disc, the cylindrical pipe is fixed in inner rings of the four rows of tapered roller bearings, a motor mounting position (19) is arranged on the lower surface of the counterweight bearing seat (2) close to the circumferential edge of the fluted disc, a driving motor (15) is clamped in the motor mounting position (19), a driving gear is fixed at the top end of an output shaft of the driving motor (15), and the driving gear is meshed with the fluted disc on the gear barrel (14); the fixed ring piece (6) is fixed on the lower surface of the fluted disc through bolts, an annular groove is formed in the upper surface of the fixed ring piece (6), four clamping blocks (16) which are distributed in central symmetry are arranged on the inner circumferential wall of the fixed ring piece (6), four groups of self-locking screw holes are formed in the outer circumferential wall of the fixed ring piece (6), four groups of self-locking screw holes are in threaded connection with four self-locking screw rods (17), the end portions of the self-locking screw rods (17) abut against the surfaces of the clamping blocks (16), straight bars are fixed on one sides, far away from the central point, of the four clamping blocks (16), the clamping blocks (16) are ensured to extend in the radial direction, the pushing square tubes (18) are clamped among the four clamping blocks (16), and abutting nuts are in threaded connection with one ends, close to the clamping blocks (16), of the outer circumferential wall of the self-locking screw rods (17).

6. A drilling device according to claim 1, characterized in that the inner circumferential wall of the sampling rod (11) is provided with a plurality of annular oil grooves (30) which are distributed at equal intervals, and the cross section of the annular oil grooves (30) is in a right triangle structure.

7. A drilling device according to claim 1, characterized in that the bore diameter of the drill bit (10) is equal to 1-1.1 times the inner diameter of the sampling rod (11).

8. A drilling device according to claim 7, characterized in that four protruding anti-twist ribs (25) are fixed on the circumferential outer wall of the drill bit (10) near the top end, a large-diameter flared sleeve (24) is reserved at the bottom end of the sampling rod (11), a notch matched with the anti-twist ribs (25) is formed in the circumferential inner wall of the flared sleeve (24), a fastening screw hole (26) penetrating through the notch is formed in the circumferential outer wall of the flared sleeve (24), and a locking bolt is screwed in the fastening screw hole (26).

9. A drilling device according to claim 1, characterized in that the outer circumferential wall of the sampling rod (11) near the top end is provided with three L-shaped anti-slip grooves (20) distributed in a central symmetry manner, the bottom end of the intermediate rod (7) is reserved with three L-shaped extension blocks (23) matched with the L-shaped anti-slip grooves (20), and the extension direction of the L-shaped anti-slip grooves (20) is matched with the rotation direction of the drill bit (10).

10. A drilling device according to claim 9, wherein the top ends of the sampling rod (11) and the intermediate rod (7) are provided with spring grooves (22) below the L-shaped anti-drop grooves (20), and the spring grooves (22) are slidably connected with locking sleeves (21), the inner walls of the locking sleeves (21) are reserved with lugs extending into the spring grooves (22), and compression springs are fixed on the lower surfaces of the lugs.