Core drill and drilling rig

Abstract

The application discloses a coring drill, relates to the technical field of shallow layer drilling, and mainly comprises a coring outer tube, a core tube, a mandrel and a drill bit. The two ends of the coring outer tube are connected with driving devices and the drill bit respectively. The mandrel is rotatably arranged in the inner cavity of the coring outer tube. The core tube is fixedly connected with the mandrel. The outer wall of the core tube is arranged close to the inner wall of the coring outer tube with a gap. The gap is not greater than 1 mm. The inner diameter of the drill bit is not greater than 30 mm. The inner diameter of the core tube is not less than the inner diameter of the drill bit. The application further discloses a drilling machine comprising the coring drill. The application can be suitable for coring of hard rock in the shallow layer and can ensure a large coring amount.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of shallow layer drilling, in particular to a coring drilling tool and a drilling machine. BACKGROUND

[0002] Some remote areas due to complex terrain, soil is not the same factors, such as traditional geological exploration methods such as manual field drilling, truck-mounted drilling rig, etc., in these areas when mineral resources investigation is faced with many challenges. Because the current coring drilling tool is mainly for deep drilling, the length and diameter of the drill pipe are very large, for specific shallow layer hard rock coring work, the diameter of the drill pipe is too large, which may cause the drilling instability, and the traditional sampling method is difficult to achieve. In view of this, there is currently a water isolation type single-action double-tube coring drilling tool, but due to the stability of the hole wall, the diameter of the drill pipe applied to soft stratum needs to be small, and the core tube and the mandrel are correspondingly arranged, the diameter of the core tube is much smaller than that of the drill pipe, which greatly reduces the capacity of the core tube, and ultimately leads to less coring amount, which cannot truly reflect the overall strength distribution of the stratum, thereby resulting in inaccurate evaluation results. Therefore, there is an urgent need for a coring drilling tool and a drilling machine to solve the above technical problems. SUMMARY

[0003] The purpose of the present application is to provide a coring drilling tool and a drilling machine to solve the problems existing in the prior art, which can adapt to shallow layer geological coring and ensure a large coring amount.

[0004] To achieve the above purpose, the present application provides the following solutions:

[0005] The present application provides a coring drilling tool, which comprises a coring outer tube, a core tube, a mandrel and a drill bit, both ends of the coring outer tube are connected with a driving device and a drill bit respectively, the mandrel is rotationally arranged in the inner cavity of the coring outer tube, the core tube is fixedly connected with the mandrel, the outer wall of the core tube is arranged close to the inner wall of the coring outer tube with a gap, the gap is not greater than 1mm, the inner diameter of the drill bit is not greater than 30mm, and the inner diameter of the core tube is not less than the inner diameter of the drill bit.

[0006] In some embodiments, a changeover joint is further included, the changeover joint is a hollow shaft joint, the mandrel is fixedly connected with the inner hole of the changeover joint, and the core tube is fixedly connected with the outer edge of the changeover joint.

[0007] In some embodiments, a first locking nut is further included, the mandrel is threadedly connected with the changeover joint, the first locking nut is threadedly connected with the mandrel and is sleeved on the mandrel, and the first locking nut is arranged above the changeover joint and is arranged in close contact.

[0008] In some embodiments, a transmission joint is further included, two ends of the transmission joint are fixedly connected with the driving device and the coring outer tube respectively.

[0009] In some embodiments, a bearing is further included, an inner ring of the bearing is fixedly connected with the mandrel, and an outer ring of the bearing is fixedly connected with the coring outer tube.

[0010] In some embodiments, a second locking nut is further included, the second locking nut is sleeved on the mandrel and connected through threads, and a top of the second locking nut is arranged in abutment with the inner ring of the bearing.

[0011] In some embodiments, a plug is further included, the plug is fixedly arranged at an end of the mandrel close to the core tube, for plugging the end of the mandrel close to the core tube, and a water outlet hole is arranged on a side wall of the mandrel, for discharging drilling fluid.

[0012] In some embodiments, the drill bit includes a drill bit body and a polycrystalline diamond composite blade, the polycrystalline diamond composite blade is arranged in an inclined manner at an end of the drill bit body and fixedly connected, and is uniformly arranged along a circumference of the drill bit body.

[0013] In some embodiments, a core clamping spring and a clamping spring seat are further included, the core clamping spring is fixedly arranged in the clamping spring seat, and the clamping spring seat is fixedly arranged at one end of the core tube close to the drill bit.

[0014] The present application also provides a drilling rig comprising the coring drilling tool as described above.

[0015] The present application has the following technical effects relative to the prior art:

[0016] The present application provides that two ends of the coring outer tube are connected with the driving device and the drill bit respectively, the mandrel is arranged in rotation in the inner cavity of the coring outer tube, the core tube is fixedly connected with the mandrel, and the core tube is arranged in abutment with the inner wall of the coring outer tube, the inner diameter of the drill bit is not greater than 30 mm, and the inner diameter of the core tube is not less than the inner diameter of the drill bit, the core tube is arranged in the inner cavity of the coring outer tube and in abutment with the inner wall, which ensures that the core tube can obtain the maximum diameter, the inner diameter of the drill bit is not greater than 30 mm, compared with the inner diameter of the drill bit of the conventional wireline coring, which is not less than 36.5 mm, the inner diameter is smaller, the coring drilling hole of the shallow surface is smaller, the hole wall is more stable, and the coring of the shallow surface geology can be adapted. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to make the technical solutions in the embodiments of the present application or the prior art clearer, the accompanying drawings needed in the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description only represent some of the embodiments of the present application, and all of the other drawings obtained by those of ordinary skill in the art without any creative effort based on these drawings belong to the protection scope of the present application.

[0018] Fig. 1 Structure diagram of the core drill in some embodiments of the present application;

[0019] Fig. 2 Structure diagram of the drill bit in some embodiments of the present application.

[0020] In the figure: 1-transmission joint; 2-core shaft; 3-core outer tube; 4-bearing; 5-second locking nut; 6-first locking nut; 7-transformation joint; 8-plug; 9-core tube; 10-core spring; 11-spring seat; 12-drill bit; 13-polycrystalline diamond composite blade; 14-drill bit body. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments only represent some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those of ordinary skill in the art without any creative effort belong to the protection scope of the present application.

[0022] The present application aims to provide a core drill and a drilling machine to solve the problems in the prior art, which can adapt to the core drilling of the superficial layer of the earth and ensure a large amount of core.

[0023] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] Embodiment one

[0025] As Figs. 1-2As shown, the present application provides a coring drill tool, which comprises a coring outer tube 3, a core tube 9, a mandrel 2, a transition joint 7 and a drill bit 12. The two ends of the coring outer tube 3 are respectively connected to a driving device and the drill bit 12. The coring outer tube 3 can rotate relative to the mandrel. The core tube 9 is fixedly connected to the mandrel 2. The outer wall of the core tube 9 is arranged close to the inner wall of the coring outer tube 3 with a gap. The gap is not greater than 1 mm, and the specific gap is an annular gap, which serves as a water flow space of the drilling fluid and can allow the drilling fluid to flow. The inner diameter of the drill bit 12 is not greater than 30 mm, and the inner diameter of the core tube 9 is not less than the inner diameter of the drill bit 12. Preferably, the inner diameter of the core tube 9 is equal to the inner diameter of the drill bit 12. The core tube 9 is arranged close to the inner wall of the coring outer tube 3, which can make the core tube 9 obtain the largest possible diameter under the given structural conditions. The core tube 9 with a larger diameter can accommodate a thicker core sample, which helps to obtain a more complete and representative core, thereby improving the accuracy and reliability of geological analysis. The inner diameter of the drill bit 12 is not greater than 30 mm, which is smaller than the inner diameter of a conventional wireline coring drill bit (not less than 36.5 mm). The smaller inner diameter of the drill bit means that the diameter of the borehole is smaller when coring is performed at the shallow surface. The small-diameter borehole has less disturbance to the surrounding strata, and the hole wall is more stable, reducing the probability of problems such as hole wall collapse, and is more suitable for geological conditions of the shallow surface that are relatively soft or unstable.

[0026] In some embodiments, the coring drill tool further comprises a transition joint 7, which is a hollow shaft-shaped joint. The mandrel 2 is fixedly connected to the inner hole of the transition joint 7, and the core tube 9 is fixedly connected to the outer edge of the transition joint 7. The outer edge of the transition joint 7 is fixedly connected to the core tube 9. Since the transition joint 7 can be enlarged in diameter according to design requirements, it can provide a larger installation space for the core tube 9, thereby maximizing the diameter of the core tube 9. The core tube 9 with a larger diameter can obtain a thicker core sample, which is beneficial for more accurate analysis of geological structure and properties. The design of the transition joint 7 plays a role in diameter conversion. The connection end of the transition joint 7 with the mandrel 2 has a smaller diameter, which is convenient for stable connection with the mandrel 2. The connection end of the transition joint 7 with the core tube 9 is enlarged in diameter, which provides a larger diameter connection basis for the core tube 9, which can not only ensure the stability of the connection between the components, but also fully utilize the space to maximize the diameter of the core tube 9.

[0027] It should be noted that the transition joint can also be in the shape of a stepped shaft, with a small head end having a diameter close to that of the mandrel 2 and being fixedly connected to the mandrel 2, and a large head end having a diameter close to that of the core tube 9 and being fixedly connected to the core tube 9.

[0028] In some embodiments, the coring drill further comprises a first locking nut 6, the mandrel 2 is threadedly connected with the adapter 7, which can ensure the coaxiality of the mandrel 2, the adapter 7 and the core barrel 9 to a certain extent, the first locking nut 6 is threadedly connected with the mandrel 2 and is sleeved on the mandrel 2, and the first locking nut 6 is arranged above the adapter 7 and is arranged in abutment, which can play a secondary fastening role on the connection of the mandrel 2 and the adapter 7, effectively preventing the loosening of the threaded connection between the mandrel 2 and the adapter 7 due to factors such as vibration and torque during coring operation, thereby ensuring the structural stability of the entire coring drill during work and ensuring the smooth progress of the coring work.

[0029] As a preferred embodiment, two first locking nuts 6 are arranged above and below the mandrel 2 in the axial direction of the mandrel 2 and are arranged in abutment, which can further ensure the fastening of the connection between the mandrel 2 and the adapter 7.

[0030] In some embodiments, the coring drill further comprises a transmission joint 1, both ends of the transmission joint 1 are fixedly connected with the driving device and the coring outer tube 3, respectively. The transmission joint 1 can stably and efficiently transmit the power of the driving device to the coring outer tube 3. During the coring operation, the rotary power generated by the driving device is accurately transmitted to the coring outer tube 3 through the transmission joint 1, ensuring that the coring outer tube 3 can rotate at a predetermined speed and torque, thereby ensuring that the drill bit 12 can effectively crush rocks and achieve the purpose of coring. It should be noted that the structures such as the transmission joint 1 and the coring outer tube 3 of the present embodiment can be made of 7075 aerospace aluminum, which is light in weight, high in strength, corrosion-resistant and wear-resistant, and can be used for a long time in a relatively complex outdoor environment.

[0031] In some embodiments, the coring drill further comprises a bearing 4, the inner ring of the bearing 4 is fixedly connected with the mandrel 2, and the outer ring of the bearing 4 is fixedly connected with the coring outer tube 3. The bearing 4 enables the mandrel 2 and the coring outer tube 3 to rotate relatively independently. During the coring operation, the driving device drives the coring outer tube 3 to rotate, while the mandrel 2 can maintain a relatively stable rotating state or rotate at different speeds as needed through the support of the bearing 4. The presence of the bearing 4 can reduce the direct friction between the mandrel 2 and the coring outer tube 3. In the absence of the bearing 4, the relative movement between the mandrel 2 and the coring outer tube 3 can cause serious friction and wear, which not only reduces the service life of the equipment, but also affects the normal progress of the coring operation. The bearing 4 can reduce the wear between components by rolling through rolling elements (such as balls, rollers, etc.), thereby prolonging the overall service life of the coring drill.

[0032] As a preferred embodiment, two bearings 4 are arranged at intervals in the axial direction of the core shaft. The two bearings 4 can jointly bear the force in the radial direction of the core shaft 2. During coring, the drill bit 12 will generate a large radial reaction force when breaking rocks. With the support of the two bearings 4, these forces can be more effectively dispersed, avoiding the single bearing 4 from being damaged due to bearing excessive radial load, thereby improving the overall carrying capacity and reliability of the coring tool.

[0033] In some embodiments, the coring tool further comprises a second locking nut 5, which is sleeved on the core shaft 2 and threadedly connected with the core shaft 2, and the top of the second locking nut 5 is fitted to the inner ring of the bearing 4. The second locking nut 5 can firmly fix the inner ring of the bearing 4 on the core shaft 2, preventing the inner ring of the bearing 4 from moving axially relative to the core shaft 2 due to vibration, impact or axial force during coring.

[0034] As a preferred embodiment, the core shaft 2 is in the shape of a stepped shaft, the large end of the core shaft 2 is fixedly connected with the inner ring of the bearing 4, the small end of the core shaft 2 is fixedly connected with the swivel joint 7, and the second locking nut 5 is threadedly connected with the small end of the core shaft 2. The core shaft 2 is in the shape of a stepped shaft, the large end has a larger diameter, and when it is fixedly connected with the inner ring of the bearing 4, it can provide a larger contact area, making the bearing 4 more stable and accurate in installation. The larger contact area can evenly distribute the load borne by the bearing 4, reducing local stress concentration, thereby prolonging the service life of the bearing 4 and improving the reliability of the coring tool.

[0035] In some embodiments, the coring tool further comprises a plug 8, which is fixedly arranged at the end of the core shaft 2 close to the core barrel 9, for plugging the end of the core shaft 2 close to the core barrel 9, and the side wall of the core shaft 2 is provided with a water outlet hole for discharging drilling fluid between the core barrel 9 and the coring outer tube 3, and finally discharging to the borehole through the water outlet hole on the drill bit. The presence of the plug 8 can prevent drilling fluid from directly entering the inside of the core barrel 9, preventing the drilling fluid from contaminating the core sample. The drilling fluid may contain various chemical components and impurities, which may change the physical and chemical properties of the core if they enter the core barrel 9 and come into contact with the core, affecting the accuracy of geological analysis. The plug 8 can act as an isolation to ensure that the core sample is not adversely affected by the drilling fluid. The water outlet hole provided on the side wall of the core shaft 2 can smoothly discharge the drilling fluid, ensuring the smooth circulation path of the drilling fluid.

[0036] In some embodiments, the drill bit 12 includes a drill bit body 14 made of manganese steel and polycrystalline diamond composite blades 13 (PDC composite blades) that are obliquely arranged at the end of the drill bit body 14 and fixedly connected, and uniformly arranged along the circumference of the drill bit body 14. The obliquely arranged PDC composite blades contact the rock more reasonably during drilling, can cut into the rock at a more favorable angle, and make the cutting force more effectively act on the rock, thereby improving the efficiency of breaking the rock. Compared with vertical arrangement, the oblique blades can take advantage of the anisotropy of the rock, more easily cause the rock to crack and break, especially when drilling hard rock or strong abrasive strata, can significantly improve the drilling speed, and the blades arranged obliquely are less resistant than the vertical blades and are less likely to fall off. By equipping with multiple types of drill bits, different situations such as soft strata, medium-hard strata, and part of hard strata can be dealt with.

[0037] In some embodiments, the coring drill tool further includes a core clamp spring 10 and a clamp spring seat 11, the core clamp spring 10 is fixedly arranged in the clamp spring seat 11, and the clamp spring seat 11 is fixedly arranged at one end of the core barrel 9 close to the drill bit. When the core enters the core barrel 9, the core clamp spring 10 is in a retracted state, and when the core enters the core barrel 9, the core clamp spring 10 can tightly clamp the core. When the coring drill tool is lifted, the core clamp spring 10 can prevent the core from falling out of the core barrel 9, ensure that the core sample is completely taken out, improve the success rate of coring and the integrity of the core, and provide reliable samples for subsequent geological analysis.

[0038] It should be further noted that, in the present embodiment, the transmission joint 1 and the coring outer pipe 3 are connected by threads, the mandrel 2 and the changeover joint 7 are connected by threads, the plug 8 and the changeover joint 7 are connected by threads and sealed at the end of the mandrel 2, and the drill bit and the coring outer pipe 3 are connected by threads. In the present embodiment, all threaded connections are trapezoidal threaded connections. The profile design of the trapezoidal thread enables it to withstand large loads in both the axial and radial directions. Its profile angle and thread height are specially designed relative to ordinary threads to provide higher tensile, compression, and torsional strength, ensuring that the pipe connection remains firm and reliable in complex working conditions, such as high pressure and high torque, and is less likely to experience thread backoff or breakage. The profile structure of the trapezoidal thread can achieve good sealing effect. When tightening the threads, the cooperation between the inner and outer threads is tight, which can effectively prevent the leakage of fluids such as oil and natural gas. In addition, in some applications, sealing grease or other sealing materials can be used to further enhance the sealing performance, ensure the safety and reliability of the pipe system, and reduce the risk of resource waste and environmental pollution caused by leakage.

[0039] Embodiment Two

[0040] The embodiment also provides a drilling machine, which comprises the coring drilling tool in the first embodiment, can adapt to superficial geological coring, and can ensure a large coring amount.

[0041] The principle and implementation of the present application are described by using specific examples in the present application. The above examples are only used to help understand the method and core idea of the present application. Meanwhile, for those skilled in the art, the specific implementation and application range will be changed according to the idea of the present application. In conclusion, the content of the present specification should not be understood as a limitation of the present application.

Claims

1. A coring drill tool characterized by: The core drill tool comprises a coring outer tube, a core tube, a mandrel, a change-over joint, a plug and a drill bit, two ends of the coring outer tube are connected with a driving device and the drill bit respectively, the mandrel is rotatably arranged in an inner cavity of the coring outer tube, the core tube is fixedly connected with the mandrel, an outer wall of the core tube is arranged close to an inner wall of the coring outer tube with a gap, the gap is not greater than 1 mm, an inner diameter of the drill bit is not greater than 30 mm, and an inner diameter of the core tube is not less than the inner diameter of the drill bit, the change-over joint is a hollow shaft-shaped joint, the mandrel is fixedly connected with an inner hole of the change-over joint, the core tube is fixedly connected with an outer edge of the change-over joint, the plug is fixedly arranged at an end of the mandrel close to the core tube, and the plug is connected with the mandrel through a trapezoidal thread, the plug is used for plugging the end of the mandrel close to the core tube, a water outlet hole is arranged on a side wall of the mandrel, and the water outlet hole is used for discharging drilling fluid.

2. The coring drill tool of claim 1, wherein: The mandrel is threadedly connected with the change-over joint, a first locking nut is threadedly connected with the mandrel and is sleeved on the mandrel, and the first locking nut is arranged above the change-over joint and is arranged in abutment.

3. The coring drill tool of claim 1, wherein: A transmission joint is fixedly connected with the driving device and the coring outer tube at two ends thereof.

4. The coring drill tool of claim 1, wherein: A bearing is fixedly connected with the mandrel at an inner ring thereof and is fixedly connected with the coring outer tube at an outer ring thereof.

5. The coring drill tool of claim 4, wherein: A second locking nut is sleeved on the mandrel and is connected through a thread, and a top of the second locking nut is arranged in abutment with the inner ring of the bearing.

6. The coring drill tool of claim 1, wherein: The drill bit comprises a drill bit body and a polycrystalline diamond composite blade, the polycrystalline diamond composite blade is arranged in abutment at an end of the drill bit body and is fixedly connected, and is uniformly arranged along a circumferential direction of the drill bit body.

7. The coring drill tool of claim 1, wherein: A core clamping spring and a clamping spring seat are further included, the core clamping spring is fixedly arranged in the clamping spring seat, and the clamping spring seat is fixedly arranged at one end of the core tube close to the drill bit.

8. A rig characterised in that: The core drill tool comprises the coring drill tool according to any one of claims 1-7.

Images