CN108930517A - Hard rock core drill - Google Patents

Abstract

The invention relates to a hard rock core drilling tool, comprising an outer core pipe and a hollow drill bit, the drill bit is installed at the lower end of the outer core pipe, the outer walls of the outer core pipe and the drill bit are provided with spiral grooves, the spiral grooves on the drill bit and the spiral grooves on the outer core pipe Continuous; the drill bit includes an inner drill bit and an outer drill bit, the inner drill bit is installed in the outer drill bit, the lower end of the inner drill bit has a first-stage blade, the outer wall of the outer drill bit has a second-stage blade, and coolant is provided at the first-stage blade and the second-stage blade return hole. In the present invention, the drill bit is divided into two-stage blades. The lowermost blade first drills a small hole, and then the upper blade reams the hole, which can increase the drilling speed and improve the core-taking efficiency; coolant circuit holes are arranged at the blade parts to cool The liquid can be sprayed out through the through hole to cool the blade, speed up the cooling speed of the blade, reduce the wear of the tool, and prolong the life of the blade; there is a spiral groove continuous with the drill bit on the outer core tube. The tube creates an airtight space for the coring tool and prevents contamination of the fidelity chamber.

Description

Hard Rock Coring Tools

technical field

The invention relates to the technical field of core drilling equipment, in particular to a hard rock core drilling tool.

Background technique

In the process of oilfield exploration, cores are important data for discovering oil and gas layers and studying formations, oil source layers, oil reservoirs, cap rocks, structures, etc. Through observation and research on cores, we can directly understand the lithology and physical properties of underground rock formations And oil, gas, water features. After the oilfield is put into development, it is necessary to further study and understand the sedimentary characteristics of the oil layer, the physical properties, pore structure, wettability, relative permeability, lithofacies characteristics of the reservoir, the physical simulation of the oil layer and the water flooding law of the oil layer through the core; In the development stage and the water flooding characteristics of oil layers in different water-cut stages, the distribution of remaining oil can be clarified, which can provide scientific basis for the design of oilfield development plan, layer series, well pattern adjustment and infill wells.

Core taking is to use special coring tools to take underground rocks to the ground in blocks during the drilling process. This block of rocks is called cores, through which various properties of rocks can be measured and the underground structure can be studied intuitively. and rock depositional environment, understand the nature of fluids, etc. In the process of mineral exploration and development, it is necessary to carry out drilling work according to the stratum level and depth of the geological design, put the coring tool into the well, and drill out the rock samples.

The drilling tool is an indispensable tool for getting rock cores. The existing coring bits have a slow drilling speed and low coring efficiency; Short life.

Contents of the invention

The invention aims to provide a hard rock coring drilling tool, the drill bit has two-stage blades, which can increase the drilling speed and coring efficiency; the cooling of the blades can be accelerated and the service life of the blades can be prolonged by setting coolant circuit holes.

In order to achieve the above object, the technical scheme adopted in the present invention is as follows:

A hard rock coring drill includes a hollow drill bit including a primary blade for drilling and a secondary blade for reaming.

Further, the drill includes an inner drill and an outer drill, the inner drill is installed in the outer drill, the first-stage blades are located at the lower end of the inner drill, and the second-stage blades are located on the outer wall of the outer drill.

Further, there is a first-stage blade escape notch on the position corresponding to the first-stage blade on the outer drill bit, and the first-stage blade avoidance gap is opened on the front end surface of the outer drill bit.

Further, the hard rock core drilling tool also includes an outer core pipe, the drill bit is installed at the lower end of the outer core pipe, the outer wall of the outer core pipe and the drill bit are provided with spiral grooves, the spiral groove on the drill bit and the spiral groove on the outer core pipe The slots are continuous.

Preferably, there are three first-stage blades at equal intervals in the circumferential direction.

Preferably, three second-stage blades are arranged at equal intervals in the circumferential direction.

Further, coolant circuit holes are provided at the first-stage blade and the second-stage blade on the drill bit.

Preferably, the coolant circuit hole at the second-stage blade is a strip hole.

Preferably, the coolant circuit hole at the first-stage blade is an arc-shaped hole, and the arc-shaped hole opens on the front end of the drill bit.

Furthermore, the inner wall of the drill bit is provided with a sealing ring, and the highly elastic annular sealing ring is used to realize the wrapping of the core during the coring process, to achieve the effect of isolation and quality preservation, and to achieve the goal of moisturizing and quality preservation.

Among them, the drill bit is a PCD cutter.

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

1. In the present invention, the drill bit is divided into two grades of blades. The lowermost blade first drills a small hole, and then the upper blade reams the hole, which can increase the drilling speed and improve the efficiency of coring; use hard alloy sharp edge thin lip drill bit Cut the rock formation, reduce the disturbance of the formation during the coring process, and ensure the integrity and quality of the coring;

2. A through hole is set on the blade part as a coolant circuit hole, and the coolant can be sprayed out through the through hole to cool the blade, speed up the cooling speed of the blade, reduce the wear of the blade, and prolong the life of the blade;

3. There is a spiral groove continuous with the drill bit on the outer wall of the outer core tube. As the outer core tube is screwed into the rock formation, the outer core tube creates a closed space for the coring tool to prevent the fidelity cabin from being polluted;

4. There is a sealing ring on the inner wall of the drill bit, and the highly elastic annular sealing ring is used to realize the wrapping of the core during the coring process, to achieve the effect of isolation and quality preservation, and to achieve the goal of moisturizing and quality preservation.

Description of drawings

Fig. 1 is the structural representation of drill bit;

Fig. 2 is the structural representation of outer drill cutter body;

Fig. 3 is a schematic structural view of the inner drill body;

Fig. 4 is a structural schematic diagram when the drill bit is installed on the outer core pipe;

In the figure: 1-drill bit, 2-first-stage blade, 3-second-stage blade, 4-spiral groove, 5-outer core tube, 6-coolant circuit hole, 7-first-stage blade avoidance gap, 8- Sealing ring, 11-inner drill bit, 12-outer drill bit, 111-inner drill cutter body, 112-first-level blade installation groove, 121-outer drill cutter body, 122-second-level blade installation groove.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings.

As shown in Figures 1, 2 and 3, the hard rock core drilling tool disclosed by the present invention includes a hollow drill bit 1, which is a PCD cutter. The drill bit 1 comprises a primary blade 2 for drilling and a secondary blade 3 for reaming.

The drill 1 includes an inner drill 11 and an outer drill 12 , the inner drill 11 includes a first-stage insert 2 and a hollow inner drill body 111 . As shown in Figure 3, the lower end of the inner drill body 111 has a first-level blade installation groove 112 for installing the first-level blade 2, and the first-level blade installation groove 112 is opened on the lower end surface of the inner drill body 111. There is a coolant circuit hole 6 at the first-stage blade installation groove 112 on the body 111 , and the coolant circuit hole 6 is an arc-shaped hole, which opens on the front end of the drill bit 1 and communicates with the first-stage blade installation groove 112 . The inner drill body 111 is provided with three first-level blade mounting grooves 112 at equal intervals in the circumferential direction, and each first-level blade mounting groove 112 is provided with a coolant circuit hole 6, and each first-level blade mounting groove 112 First stage blades 2 are installed in the middle. The inner wall of the inner drill body 111 is provided with a sealing ring 8, and the highly elastic annular sealing ring is used to wrap the rock core during the coring process, achieve the effect of isolation and quality preservation, and achieve the goal of moisturizing and quality preservation.

The outer drill 12 includes a second-stage insert 3 and a hollow outer drill body 121 . As shown in Figure 2, the outer wall of the second-stage blade 3 has a second-stage blade mounting groove 122 for installing the second-stage blade 3, and the second-stage blade mounting groove 122 on the outer drill body 121 has a coolant circuit hole 6, The coolant circuit hole 6 is a bar-shaped hole, and the bar-shaped hole communicates with the second-stage blade mounting groove 122 . The outer drill body 121 is provided with three second-level blade mounting grooves 122 at equal intervals in the circumferential direction, and each second-level blade mounting groove 122 is provided with a coolant circuit hole 6, and each second-level blade mounting groove 122 Second stage blade 3 is installed in all.

The inner drill bit 11 is installed in the outer drill bit 12, and the position corresponding to the first-level blade 2 on the outer drill body 121 has a first-level blade avoidance gap 7, and the first-level blade avoidance gap 7 is opened on the front end of the outer drill bit 12. The cutting edge of the first-stage blade 2 is exposed to the outer drill body 121 from the first-stage blade avoidance gap 7 . The thickness of the blade in this embodiment is 3.2 mm.

Drill bit is divided into two-stage blade among the present invention, drills small hole at first by the first-stage blade 2 of the lowest end, then reaming by the second-stage blade 3 of top, can improve drilling speed. Through holes are arranged at the blade parts as the cooling liquid circuit holes 6, and the cooling liquid can be sprayed out through the through holes to cool the blades. The invention utilizes the hard alloy sharp-mouth thin-lip drill bit to cut the rock formation, reduces the disturbance to the stratum during the coring process, and ensures the integrity and quality of the coring.

As shown in Figure 4, in another embodiment, the hard rock core drilling tool also includes an outer core pipe 5, the drill bit 1 is installed at the lower end of the outer core pipe 5, and the upper end of the outer drill body 121 is connected with the lower end of the outer core pipe 5, The outer walls of the outer core tube 5 and the outer drill body 121 are provided with spiral grooves 4 , and the spiral grooves 4 on the outer drill body 121 are continuous with the spiral grooves 4 on the outer core tube 5 . The outer wall of the outer core tube 5 with the spiral groove 4 is equivalent to the helical outer drill. As the outer core tube 5 is screwed into the rock formation, the outer core tube 5 creates a closed space for the coring tool. package to prevent contamination of the fidelity chamber.

Certainly, the present invention also can have other multiple implementation modes, without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention, but these corresponding changes All changes and modifications should belong to the scope of protection of the appended claims of the present invention.

Claims (10)

1. hard rock coring drill, is characterized in that: comprise hollow drill bit (1), and described drill bit (1) comprises the first stage blade (2) that is used for drilling and the second stage blade that is used for reaming (3). 2. The hard rock core drilling tool according to claim 1, characterized in that: the drill bit (1) comprises an inner drill bit (11) and an outer drill bit (12), and the inner drill bit (11) is installed on the outer drill bit ( 12) In the interior, the first stage blade (2) is positioned at the lower end of the inner drill bit (11), and the second stage blade (3) is positioned at the outer wall of the outer drill bit (12). 3. The hard rock core drilling tool according to claim 2, characterized in that: there is a first-stage blade avoidance gap (7) at the position corresponding to the first-stage blade (2) on the outer drill bit (12), and the first-stage blade avoids a gap (7). The blade escape notch (7) is opened on the front end face of the outer drill bit (12). 4. The hard rock core drilling tool according to claim 1 or 2, characterized in that: it also includes an outer core pipe (5), the drill bit (1) is installed at the lower end of the outer core pipe (5), and the outer core Both the pipe (5) and the drill bit (1) are provided with spiral grooves (4) on the outer walls, and the spiral grooves (4) on the drill bit (1) are continuous with the spiral grooves (4) on the outer core pipe (5). 5. The hard rock core drilling tool according to claim 1, 2 or 3, characterized in that three first-stage blades (2) are arranged at equal intervals in the circumferential direction. 6. The hard rock core drilling tool according to claim 1 or 2, characterized in that three second-stage blades (3) are arranged at equal intervals in the circumferential direction. 7. The hard rock core drilling tool according to claim 1 or 2, characterized in that: the first-stage blade (2) and the second-stage blade (3) on the drill bit (1) are provided with coolant circuit holes (6). 8. The hard rock core drilling tool according to claim 7, characterized in that: the coolant circuit hole (6) at the second-stage blade (3) is a strip hole, and the hole at the first-stage blade (2) is The coolant circuit hole (6) is an arc-shaped hole, and the arc-shaped hole opens on the front end face of the drill bit (1). 9. The hard rock core drilling tool according to claim 1 or 2, characterized in that: a sealing ring (8) is provided on the inner wall of the drill bit (1). 10. The hard rock core drilling tool according to claim 1 or 2, characterized in that the drill bit (1) is a PCD cutter.