CN219061524U - Core drill without lifting drill and replacing drill bit - Google Patents

Abstract

The utility model belongs to the technical field of geological exploration, and particularly relates to a core drill without lifting a drill bit to replace a drill bit. The outer circular surface of the first circular tube and the outer circular surface of the second circular tube of the core drill connecting tube are not coaxial, and the inner hole of the first circular tube and the outer circular surface of the second circular tube are coaxial; the inner hole of the reamer is not coaxial with the outer circular surface of the reamer; the inner hole of the drill bit is not coaxial with the outer circular surface of the drill bit; when drilling, the connecting pipe rotates to enable the inner hole of the first circular pipe to be different from the outer circular surface of the reamer, and at the moment, the outer circular surface of the reamer is different from the outer circular surface of the drill bit; when salvaging, the connecting pipe rotates to enable the inner hole of the first circular pipe to be coaxial with the outer circular surface of the reamer, and at the moment, the outer circular surface of the reamer is coaxial with the outer circular surface of the drill bit. Therefore, the core drill realizes the change of the diameters of the periphery of the reamer and the drill bit by controlling the cooperation of the connecting pipe and the reamer, thereby obtaining an eccentric drilling position and a concentric salvaging position, and realizing the purpose of replacing the drill bit while having the coring function.

Description

Core drill without lifting drill and replacing drill bit

Technical Field

The utility model belongs to the technical field of geological exploration, and particularly relates to a core drill without lifting a drill bit to replace a drill bit.

Background

Geological exploration is to survey and detect geology through various means and methods to determine a proper bearing layer, and then determine the foundation type of the geology according to the foundation bearing capacity of the bearing layer. Drilling techniques are one type of geological exploration in which basic parameters of the geology can be calculated. The drilling tool outer tube is sleeved with an inner tube assembly, and the inner tube assembly comprises a core tube. In the drilling process, the core is slowly arranged in the core taking pipe, when the core is filled with the core taking pipe, a fisher with a rope is adopted, the inner pipe assembly is lifted out from the outer pipe, the core is collected, and then the inner pipe assembly is lowered to the bottom of the hole to continue drilling.

However, due to the abrasion of the drill bit and the change of rock stratum, the drill bit needs to be replaced irregularly, so that a lifting drill rod for replacing and checking the drill bit is also required to be arranged in the rope coring drilling technology to carry out the lifting operation of the drill rod, and the original drilling work is influenced by adding another lifting operation of the drill rod in the drilling work, so that the problems of short pure drilling time and low drilling efficiency occur.

Disclosure of Invention

First, the technical problem to be solved

In order to solve the problems in the prior art, the utility model provides a core drill without lifting a drill to replace a drill bit, thereby solving the technical problem of low drilling efficiency.

(II) technical scheme

In order to achieve the above purpose, the main technical scheme adopted by the utility model comprises the following steps:

the utility model provides a core drill without lifting a drill to replace a drill bit, which comprises an inner pipe, wherein the inner pipe comprises a connecting pipe, the connecting pipe comprises a first circular pipe and a second circular pipe which are sequentially connected, the outer diameter of the first circular pipe is smaller than that of the second circular pipe, the outer circular surface of the first circular pipe is not coaxial with the outer circular surface of the second circular pipe, and the inner hole of the first circular pipe is coaxial with the outer circular surface of the second circular pipe; the core drill bit further comprises an reamer, wherein an inner hole of the reamer is not coaxial with the outer circular surface of the reamer, and the reamer is rotatably sleeved outside the first circular tube; the core drill further comprises a drill bit, the drill bit comprises a drill bit inner hole and a drill bit outer circular surface, the drill bit inner hole is not coaxial with the drill bit outer circular surface, the drill bit is sleeved at the front end of the first circular pipe, and the reamer is positioned between the drill bit and the second circular pipe; when drilling, the connecting pipe rotates to enable the inner hole of the first circular pipe to be different from the outer circular surface of the reamer, and at the moment, the outer circular surface of the reamer is different from the outer circular surface of the drill bit; when salvaging, the connecting pipe rotates to enable the inner hole of the first circular pipe to be coaxial with the outer circular surface of the reamer, and at the moment, the outer circular surface of the reamer is coaxial with the outer circular surface of the drill bit.

Further, a large arc hole and a small arc hole which are used for surrounding an inner hole of the combined reamer are arranged in the reamer, the large arc hole and the small arc hole are coaxial, a first end face and a second end face are respectively formed at the joint of the two ends of the large arc hole and the small arc hole, concave surfaces formed by the first end face, the second end face and the large arc hole are eccentric key grooves, eccentric keys with the upper ends being arc surfaces are arranged on the first round pipe, the arc surfaces are coaxial with the outer circular surface of the first round pipe, and the eccentric key grooves are matched with the eccentric keys; the outer diameter of the reamer, the outer diameter of the drill bit and the outer diameter of the second round tube are all the same.

Further, the inner tube further comprises an inner tube assembly, the inner tube assembly comprises a core taking tube, the core taking tube penetrates through the connecting tube, and a fixing assembly is connected behind the core taking tube to fix the core taking tube axially.

Further, the drill bit also comprises a coring inner hole, wherein the coring inner hole is coaxial with the outer circular surface of the drill bit, and when drilling, the front end of the coring pipe is positioned in the drill bit and is coaxial with the coring inner hole.

Further, the connecting pipe further comprises a third circular pipe connected with the second circular pipe, the third circular pipe is coaxial with the second circular pipe, and the outer diameter of the third circular pipe is smaller than that of the second circular pipe; the fixing component comprises a spring clip and a spring clip chamber, the spring clip is fixed at the tail end of the core taking pipe, the spring clip chamber is cylindrical, the spring clip chamber is sleeved outside the tail end of the third circular pipe and fixedly connected with the third circular pipe, and the spring clip is positioned in the spring clip chamber and is clamped with the spring clip chamber.

Further, the core drill bit also comprises an outer tube, the outer tube comprises a connecting frame and a shell, the connecting frame is cylindrical, the connecting frame is sleeved at the front end of the second circular tube, and the front end face of the connecting frame is aligned with the front end face of the second circular tube; the rear end face of the reamer is propped against the front end face of the second round tube; the shell is cylindrical, the shell is sleeved outside the inner pipe, and the shell is fixedly connected with the tail end of the connecting frame.

Further, the core drill bit also comprises a salvaging mechanism, the salvaging mechanism is positioned in the shell and comprises a heavy hammer and a salvaging hook which are integrally formed; the inner tube assembly still includes the connecting axle, and the connecting axle sets up in the bullet card and wears out from the bullet card room, and the weight center is provided with the connecting hole, and the connecting axle is fixed with the connecting hole cooperation, salvages the tail end that the hook is located the casing.

Further, a sealing piston is arranged in a space surrounded by the second circular tube, the third circular tube, the spring clamping chamber and the shell, and the third circular tube penetrates through an inner hole of the sealing piston.

Further, a guide component is arranged at the matched and connected part of the connecting frame and the second round tube.

Further, the guide assembly includes a guide spline disposed on the outer surface of the forward end of the second barrel and a guide spline groove disposed in the coupling frame.

(III) beneficial effects

The beneficial effects of the utility model are as follows:

according to the core drill without lifting the drill to replace the drill bit, the change of the diameters of the periphery of the reamer and the drill bit is realized by controlling the cooperation of the connecting pipe and the reamer, so that the eccentric drilling position and the concentric salvaging position are obtained, and the purpose of replacing the drill bit while having a coring function is realized.

The utility model can realize the function of replacing the drill bit without lifting the drill rod to lift the whole drill bit, greatly shortens the time for replacing the drill bit, simultaneously can complete the actions of drilling, coring and the like, provides convenient and simple operation for geological exploration, improves the whole drilling efficiency and saves the drilling cost.

Drawings

FIG. 1 is a schematic cross-sectional view of a core drill without lifting the drill to replace the bit;

FIG. 2 is a schematic structural view of a connection pipe;

FIG. 3 is a schematic structural view of a connector;

FIG. 4 is a schematic view of the reamer;

FIG. 5 is a schematic view of the structure of a drill bit;

FIG. 6 is a schematic view of the positioning of the drill bit, reamer and connection tube during drilling;

fig. 7 is a schematic view of the position structure of the drill bit, reamer and connection pipe at the time of fishing.

[ reference numerals description ]

1: an inner tube; 11: a connecting pipe; 111: a first round tube; 112: a second round tube; 113: an eccentric key; 114: a third round tube; 12: an inner tube assembly; 121: taking a core tube; 122: a fixing assembly; 1221: spring card; 1222: a card ejection chamber; 12221: a card ejection chamber hole; 123: a connecting shaft;

2: a reamer; 21: a large circular arc hole; 22: a small circular arc hole; 23: a first end face; 24: a second end face;

3: a drill bit; 31: a drill bit inner hole; 32: an outer circumferential surface of the drill bit; 33: coring an inner hole;

4: an outer tube; 41: a connecting frame; 42: a housing;

5: a guide assembly; 51: a guide spline; 52: a guide spline groove;

6: a sealing piston;

7: a salvaging mechanism; 71: a heavy hammer; 72: and fishing the hook.

Detailed Description

In order that the above-described aspects may be better understood, exemplary embodiments of the present utility model will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present utility model are shown in the drawings, it should be understood that the present utility model may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the utility model to those skilled in the art.

1-7, the utility model provides a core drill without lifting a drill to replace a drill bit, which comprises an inner pipe 1, a reamer 2, a drill bit 3, an outer pipe 4 and a salvaging mechanism 7, wherein the reamer 2 and the drill bit 3 are integrated on the inner pipe 1, and the outer pipe 4 is connected with a drill rod and a drilling machine to transmit power. Specifically, the outer tube 4 comprises a connecting frame 41 and a housing 42, the housing 42 being connected to a drill rod, a drill rig (not shown in the figures) afterwards. The inner tube 1 includes a connection tube 11 and an inner tube assembly 12, and the inner tube assembly 12 includes a coring tube 121 for coring. The drill bit 3 and reamer 2 are connected to a connection tube 11, the connection tube 11 is connected to a connection frame 41, the connection frame 41 is connected to a housing 42, and the connection tube 11 is connected to an inner tube assembly 12, thereby forming an inner and outer double tube. The fishing mechanism 7 is connected with the inner pipe assembly 12 and is positioned in the shell 42, and when the inner pipe 1 is fished, the fisher with the rope is connected with the fishing mechanism 7 for fishing.

As shown in fig. 1 and 2, the connection pipe 11 includes a first circular pipe 111, a second circular pipe 112 and a third circular pipe 114 connected in sequence, and the outer diameters of the first circular pipe 111 and the third circular pipe 114 are smaller than the outer diameter of the second circular pipe 112. The outer circumferential surface of the first circular tube 111 is not coaxial with the outer circumferential surface of the second circular tube 112, the inner hole of the first circular tube 111 is coaxial with the outer circumferential surface of the second circular tube 112, and the third circular tube 114 is coaxial with the second circular tube 112. The axis of the inner bore of the first round tube 111 is denoted as axis a, and the axis of the outer circumferential surface of the first round tube 111 is denoted as axis B.

As shown in fig. 4, the reamer 2 has two axes, the inner bore of the reamer 2 is not coaxial with the outer circumferential surface of the reamer 2, the axis of the inner bore of the reamer 2 is denoted as axis C, and the axis of the outer circumferential surface of the reamer 2 is denoted as axis D. The reamer 2 is rotatably sleeved outside the first circular tube 111 until the rear end surface abuts against the front end surface of the second circular tube 112.

As shown in fig. 5, the drill 3 has two axes, the drill 3 includes a drill inner hole 31, a drill outer circumferential surface 32, and a coring inner hole 33, the axis of the drill outer circumferential surface 32 is denoted as an axis E, the axis of the drill inner hole 31 is denoted as an axis F, the drill inner hole 31 is not coaxial with the drill outer circumferential surface 32, and the coring inner hole 33 is coaxial with the drill outer circumferential surface 32. When drilled, the front end of the coring tube 121 is positioned within the drill bit 3 and coaxial with the coring bore 33. The front end of the first circular tube 111 is provided with threads, the rear part of the drill bit 3 is sleeved at the front end of the first circular tube 111 and is in threaded connection with the first circular tube 111, and the front part of the drill bit 3 protrudes forwards out of the first circular tube 111. Further, screws can be added at the threaded connection positions, so that the drill bit 3 is prevented from falling off when the connecting pipe 11 is reversed, and the reliability of connection is ensured.

As shown in fig. 1, the reamer 2 is located between the drill bit 3 and the second circular tube 112, and the outer diameter of the reamer 2, the outer diameter of the drill bit 3, and the outer diameter of the second circular tube 112 are the same. Thereby ensuring that the reamer 2 and the drill bit 3 can be fished out together when the inner pipe 1 is fished out.

Specifically, when drilling, the connection pipe 11 is rotated such that the inner bore of the first circular pipe 111 is not coaxial with the outer circumferential surface of the reamer 2, and at this time, the outer circumferential surface of the reamer 2 is not coaxial with the bit outer circumferential surface 32.

When salvaging, the connection pipe 11 is rotated so that the inner hole of the first circular pipe 111 is coaxial with the outer circumferential surface of the reamer 2, and at this time, the outer circumferential surface of the reamer 2 is coaxial with the drill bit outer circumferential surface 32.

In this embodiment, as shown in fig. 2, an eccentric key 113 with an arc surface at the upper end is provided on the first circular tube 111, and the arc surface is coaxial with the outer circular surface of the first circular tube 111. As shown in fig. 4, a large circular arc hole 21 and a small circular arc hole 22 surrounding the inner hole of the reamer 2 are arranged in the reamer 2, the large circular arc hole 21 and the small circular arc hole 22 are coaxial, a first end face 23 and a second end face 24 are respectively formed at the joint of the two ends of the large circular arc hole 21 and the small circular arc hole 22, concave surfaces formed by the first end face 23, the second end face 24 and the large circular arc hole 21 are eccentric key grooves, and the eccentric key grooves are matched with the eccentric keys 113. Under the drive of the drilling machine, the eccentric key 113 rotates in the eccentric key groove to enable the first circular tube 111 and the reamer 2 to perform relative movement so as to realize the functions of reaming the reamer 2 and salvaging the reamer 2 and the drill bit 3.

As shown in fig. 3, the connecting frame 41 is cylindrically sleeved on the front end of the second circular tube 112, and the front end surface of the connecting frame 41 is aligned with the front end surface of the second circular tube 112. The distance between the tail end of the drill bit 3 and the front end face of the connecting frame 41 is just the length of the reamer 2, the drill bit 3, the reamer 2 and the connecting frame 41 are tightly matched, and the transmission direction of the bit pressure is ensured to be uninterrupted by tolerance control.

As shown in fig. 1, the casing 42 is cylindrically sleeved outside the inner tube 1 and fixedly connected to the tail end of the connecting frame 41. Thereby realizing the cooperation of the inner tube 1 and the outer tube 4, and achieving the purpose of transmitting torque to the drill bit 3 under the driving of the drilling machine. The guiding component 5 is arranged at the joint of the connecting frame 41 and the second round tube 112, so that the inner tube 1 and the outer tube 4 can be matched in place under any angle, the circumferential fixation of the inner tube 1 and the outer tube 4 is ensured, the torque transmitted from the drilling machine is ensured to be transmitted, and the drill bit 3 can be rotated for cutting during drilling. The mode transmission form is more effective, the safety coefficient is higher, and the operation is simple.

In this embodiment, as shown in fig. 2 and 3, the guide assembly 5 adopts a spline structure having a guiding property, and includes a guide spline 51 provided on the outer surface of the front end of the second round pipe 112 and a guide spline groove 52 provided in the connecting frame 41, which are engaged with each other.

As shown in fig. 1, the coring pipe 121 penetrates the inside of the connection pipe 11, and a fixing assembly 122 is connected to the rear of the coring pipe 121 to axially fix the coring pipe 121. The fixing assembly 122 includes a latch 1221 and a latch chamber 1222, the latch 1221 is fixed at the tail end of the core tube 121, the latch chamber 1222 is cylindrically sleeved outside the tail end of the third circular tube 114 and is in threaded connection with the third circular tube 114, the latch 1221 is located in the latch chamber 1222 and is engaged with the latch chamber 1222, and when the inner tube assembly 12 is lowered along the housing 42, the latch 1221 is opened to be engaged with an angle on an inner wall of the latch chamber 1222 to prevent the inner tube 1 from moving upward.

As shown in fig. 1, the salvaging mechanism 7 includes a weight 71 and a salvaging hook 72 integrally formed; the inner pipe assembly 12 further comprises a connecting shaft 123, the connecting shaft 123 is arranged in the bullet card 1221 and penetrates out of the bullet card chamber 1222, a connecting hole is formed in the center of the heavy hammer 71, the connecting shaft 123 is matched and fixed with the connecting hole, and the salvaging hook 72 is located at the tail end of the shell 42, so that when the inner pipe assembly 12 is salvaged by the salvaging device, the inner pipe 1 can be salvaged out together.

As shown in fig. 1, a sealing piston 6 is disposed in a space enclosed by the second circular tube 112, the third circular tube 114, the spring clip chamber 1222 and the housing 42, and the third circular tube 114 is inserted into an inner hole of the sealing piston 6. The seal piston 6 closes the gap between the housing 42 and the second barrel 112, allowing mud entering the housing 42 to flow from the bullet chamber bore 12221 into the inner tube assembly 12 portion, providing a mud cooling circulation path for the drill bit 3, reamer 2, while the seal piston 6 also ensures that the auxiliary core drill is lowered into place by the mud.

Working principle: when drilling, the inner tube 1 is lowered, under the action of mud, the drill bit 3 and the reamer 2 are punched in place along with the inner tube assembly 12, and the inner tube 1 and the outer tube 4 are integrated by the cooperation of the guide spline 51 and the guide spline groove 52, so that the inner tube and the outer tube 4 can be integrally driven to rotate by a drilling machine to jointly drill. After the inner tube 1 and the outer tube 4 are integrated, the drilling machine starts to rotate positively to provide a power source to transmit torque, so that the eccentric key 113 is abutted against the first end face 23, at the moment, the axis A of the inner hole of the first circular tube 111 is deviated from the axis D of the outer circular surface of the reamer 2, the axis D of the outer circular surface of the reamer 2 is different from the axis E of the outer circular surface 32 of the drill bit, the distance between the outer surface of the reamer 2 and the central axis of the inner tube assembly 12 is larger than the distance between the outer surface of the drill bit 3 at the same position as the outer surface of the reamer 2 and the central axis of the inner tube assembly 12, and the reaming and cutting functions can be realized.

During fishing, the drilling machine is reversed, the eccentric key 113 is abutted against the second end face 24, at this time, the axis A of the inner hole of the first circular tube 111 is coaxial with the axis D of the outer circular surface of the reamer 2, the axis D of the outer circular surface of the reamer 2 is coaxial with the axis E of the outer circular surface 32 of the drill bit, and because the outer diameter of the reamer 2, the outer diameter of the drill bit 3 and the outer diameter of the second circular tube 112 are the same, the drill bit 3 and the reamer 2 can be fished out of the outer tube 4 together with the inner tube assembly 12 through the inner hole of the connecting frame 41, and the coring or bit replacement can be performed.

In summary, the core drill without lifting the drill to replace the drill bit provided by the utility model can complete the actions of replacing the drill bit without lifting the drill, and simultaneously can complete the actions of drilling, coring and the like, thereby simplifying the operation procedures, and being simple and reliable.

In the description of the present specification, the terms "one embodiment," "some embodiments," "examples," "particular examples," or "some examples," etc., refer to particular features, structures, materials, or characteristics described in connection with the embodiment or example as being included in at least one embodiment or example of the present utility model. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

While embodiments of the present utility model have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the utility model, and that alterations, modifications, substitutions and variations may be made in the above embodiments by those skilled in the art within the scope of the utility model.

Claims (10)

1. The core drill bit without lifting a drill bit for replacing a drill bit comprises an inner pipe (1), wherein the inner pipe (1) comprises a connecting pipe (11), and is characterized in that the connecting pipe (11) comprises a first circular pipe (111) and a second circular pipe (112) which are sequentially connected, the outer diameter of the first circular pipe (111) is smaller than the outer diameter of the second circular pipe (112), the outer circular surface of the first circular pipe (111) is not coaxial with the outer circular surface of the second circular pipe (112), and the inner hole of the first circular pipe (111) is coaxial with the outer circular surface of the second circular pipe (112);

the core drill bit further comprises an reamer (2), wherein an inner hole of the reamer (2) is not coaxial with the outer circular surface of the reamer (2), and the reamer (2) is rotatably sleeved outside the first circular tube (111);

the core drilling tool further comprises a drill bit (3), the drill bit (3) comprises a drill bit inner hole (31) and a drill bit outer circular surface (32), the drill bit inner hole (31) is not coaxial with the drill bit outer circular surface (32), the drill bit (3) is sleeved at the front end of the first circular pipe (111), and the reamer (2) is positioned between the drill bit (3) and the second circular pipe (112);

when drilling, the connecting pipe (11) rotates to enable the inner hole of the first circular pipe (111) to be different from the outer circular surface of the reamer (2), and at the moment, the outer circular surface of the reamer (2) is different from the outer circular surface (32) of the drill bit;

when salvaging, the connecting pipe (11) rotates to enable the inner hole of the first circular pipe (111) to be coaxial with the outer circular surface of the reamer (2), and at the moment, the outer circular surface of the reamer (2) is coaxial with the outer circular surface (32) of the drill bit.

2. The core drill without lifting and replacing a drill bit according to claim 1, wherein a large circular arc hole (21) and a small circular arc hole (22) which are enclosed into an inner hole of the reamer (2) are arranged in the reamer (2), the large circular arc hole (21) and the small circular arc hole (22) are coaxial, a first end face (23) and a second end face (24) are respectively formed at the joint of the large circular arc hole (21) and the two ends of the small circular arc hole (22), concave surfaces formed by the first end face (23), the second end face (24) and the large circular arc hole (21) are eccentric key grooves, an eccentric key (113) with an upper end being an arc surface is arranged on the first circular tube (111), the arc surface is coaxial with the outer circular surface of the first circular tube (111), and the eccentric key grooves are matched with the eccentric key (113);

the outer diameter of the reamer (2), the outer diameter of the drill bit (3) and the outer diameter of the second circular tube (112) are all the same.

3. The core drill without lifting and replacing a drill bit according to claim 1, wherein the inner tube (1) further comprises an inner tube assembly (12), the inner tube assembly (12) comprises a core tube (121), the core tube (121) penetrates through the connecting tube (11), and a fixing assembly (122) is connected behind the core tube (121) to axially fix the core tube (121).

4. A core drill bit according to claim 3, wherein the drill bit (3) further comprises a coring bore (33), the coring bore (33) being coaxial with the bit outer circumferential surface (32), the coring pipe (121) leading end being located within the drill bit (3) and coaxial with the coring bore (33) when drilling.

5. The core drill bit of claim 3, wherein the connecting tube (11) further comprises a third tube (114) connected to the second tube (112), the third tube (114) being coaxial with the second tube (112), the third tube (114) having an outer diameter smaller than an outer diameter of the second tube (112);

the fixing assembly (122) comprises a spring card (1221) and a spring card chamber (1222), the spring card (1221) is fixed at the tail end of the coring pipe (121), the spring card chamber (1222) is cylindrical, the spring card chamber (1222) is sleeved outside the tail end of the third circular pipe (114) and fixedly connected with the third circular pipe (114), and the spring card (1221) is located in the spring card chamber (1222) and is clamped with the spring card chamber (1222).

6. The core drill bit without lifting and replacing a drill bit according to claim 5, further comprising an outer tube (4), the outer tube (4) comprising a connecting frame (41) and a housing (42), the connecting frame (41) being cylindrical, the connecting frame (41) being sleeved on the front end of the second circular tube (112), the front end surface of the connecting frame (41) being aligned with the front end surface of the second circular tube (112);

the rear end face of the reamer (2) is propped against the front end face of the second circular tube (112);

the shell (42) is cylindrical, the shell (42) is sleeved outside the inner tube (1), and the shell (42) is fixedly connected with the tail end of the connecting frame (41).

7. The core drilling tool for bit replacement without lifting a drill according to claim 6, further comprising a salvage mechanism (7), the salvage mechanism (7) being located within the housing (42), the salvage mechanism (7) comprising an integrally formed weight (71) and salvage hook (72);

the inner pipe assembly (12) further comprises a connecting shaft (123), the connecting shaft (123) is arranged in the bullet card (1221) and penetrates out of the bullet card chamber (1222), a connecting hole is formed in the center of the heavy hammer (71), the connecting shaft (123) is matched and fixed with the connecting hole, and the salvaging hook (72) is located at the tail end of the shell (42).

8. The core drill bit of claim 6, wherein a sealing piston (6) is disposed in a space defined by the second circular tube (112), the third circular tube (114), the spring clip chamber (1222) and the housing (42), and the third circular tube (114) is disposed in an inner hole of the sealing piston (6) in a penetrating manner.

9. The core drill bit of claim 6, wherein a guide assembly (5) is provided at the mating connection of the connector (41) and the second barrel (112).

10. The core drill bit of claim 9, wherein the guide assembly (5) comprises guide splines (51) disposed on the outer surface of the forward end of the second barrel (112) and guide spline grooves (52) disposed in the connecting frame (41).

Images