CN111877981A - A low-disturbance hole-forming device and method for weak mudstone bolt/cable hole - Google Patents

Abstract

The invention relates to a low-disturbance hole-forming device and method for soft and weak mudstone bolts/cable holes. The device comprises: a multi-section hollow outer drill pipe that can be connected to each other, one end of the outer drill pipe is installed with a hole-forming drill bit; The inner drill pipe is installed in the outer drill pipe, and the inner drill pipe can rotate along the axis line of the outer drill pipe. The inner drill pipe is provided with a water flow channel along the length direction of the inner drill pipe, and the inner drill pipe is provided with a spiral wings; and a crushing bit, the crushing bit is installed on one end of the inner drill rod relatively close to the hole-forming bit, and the crushing bit is provided with a water outlet, which is communicated with the water flow channel. In the present invention, the cooling of the drill bit is realized in the form of water inlet of the inner drill pipe and water outlet between the inner drill pipe and the inner wall of the outer drill pipe. The above cooling method can prevent the problem of strength reduction or even softening and collapse of the surrounding rock in the hole wall due to a large amount of water immersion.

Description

A low-disturbance hole-forming device and method for weak mudstone bolt/cable hole

technical field

The invention relates to the field of tunnel engineering bolt/cable installation hole-making engineering, in particular to a low-disturbance hole-forming device and method for a soft mudstone bolt/cable hole.

Background technique

In tunnel construction, the method of adding water to a pneumatic rock drill is often used to cool down and discharge the slag during the bolt-anchor cable hole making process.

During tunnel construction, weak mudstone is often encountered. In this case, it is not suitable to use direct water flushing to cool down and discharge slag. This is mainly because during the water flushing process of traditional pneumatic rock drills, water flows into the bottom of the hole through the drill pipe and then passes through the drill pipe. The gap with the hole wall will flow out, which will cause a lot of water immersion in the surrounding rock, and also make the mudstone rapidly soften or even expand when it encounters water, which not only aggravates the difficulty of slag extraction, but also is very unfavorable for the later stability control of the surrounding rock.

SUMMARY OF THE INVENTION

In view of the above problems, a low-disturbance hole-forming device and method for weak mudstone bolts/cable holes are provided, so as to improve the hole-making efficiency by means of auxiliary slag discharge inside the drill pipe and flushing and cooling of the passage in the drill pipe.

The specific technical solutions are as follows:

A first aspect of the present invention is to provide a low-disturbance hole-forming device for weak mudstone bolts/cable holes, having such features, including:

A multi-section hollow outer drill pipe that can be connected to each other, and one end of the outer drill pipe is installed with a hole-forming drill bit;

The inner drill pipe is installed in the outer drill pipe, and the inner drill pipe can rotate along the axis line of the outer drill pipe. The inner drill pipe is provided with a water flow channel along the length of the inner drill pipe. have helical fins; and

The crushing drill bit is installed on one end of the inner drill pipe relatively close to the hole-forming drill bit, and the crushing drill bit is provided with a water outlet hole, which is communicated with the water flow channel.

The above-mentioned low-disturbance hole-forming device also has the feature that the crushing bit is further provided with multiple spiral grooves.

The above-mentioned low-disturbance hole-forming device also has the feature that one end of the outer drill rod is provided with a first threaded joint, the other end of the outer drill rod is provided with a second threaded joint, and the hole-forming drill bit is screwed through the first threaded joint. on the outer drill pipe.

The above-mentioned low-disturbance hole-forming device also has the characteristics that the hole-forming device further comprises a plurality of support rods and a plurality of support bearings, the support bearings are installed on the inner drill rod at intervals, and one end of the support rod is installed on the inner wall of the outer drill rod, The other end of the support rod is extended and connected to the bearing outer ring of the support bearing.

The above-mentioned low-disturbance hole-forming device also has the feature that the support bearing is a tapered bearing.

The above-mentioned low-disturbance hole-forming device also has the feature that the hole-forming drill bit is made of diamond.

A second aspect of the present invention is to provide a method for forming holes using the above-mentioned low-disturbance hole-forming device, which has the characteristics of comprising the following steps:

S1. Connect several extra-section drill pipes according to the depth requirements;

S2. Inject cooling water into the water flow channel, so that the water flow flows out through the water flow channel and the water outlet in turn, thereby cooling the hole-forming drill bit and the crushing drill bit;

S3. Drive the outer drill pipe and the inner drill pipe respectively to rotate them in opposite directions, so as to use the hole-forming drill bit to rotate to break the rock and drill into the hole, and at the same time use the reverse rotation action of the helical fins 5 to flush the broken mudstone slag. Outside the drill pipe;

S4. Drill to the design depth.

The beneficial effects of the above scheme are:

1), in the present invention, adopt the form of water inlet of the inner drill pipe, water outlet between the inner drill pipe and the inner wall of the outer drill pipe to realize the cooling of the drill bit, and the above-mentioned cooling form can prevent the surrounding rock of the hole wall from reducing the strength or even softening and collapsing due to a large amount of water immersion. question;

2) In the present invention, the inner drill pipe is provided with a helical fin structure, so as to realize the slag discharge inside the outer drill pipe, so as to obtain a higher slag discharge efficiency compared with the traditional method of flushing and slag discharge by water flow alone.

Description of drawings

1 is a schematic structural diagram of a low-disturbance hole-forming device provided in an embodiment of the present invention;

FIG. 2 is a schematic cross-sectional structure diagram along the letter A-A line in FIG. 1 .

In the accompanying drawings: 1. Outer drill pipe; 2. Hole-forming drill bit; 3. Inner drill pipe; 4. Water flow channel; , the first threaded joint; 10, the second threaded joint; 11, the support rod; 12, the support bearing.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

It should be noted that the embodiments of the present invention and the features of the embodiments may be combined with each other under the condition of no conflict.

The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but it is not intended to limit the present invention.

FIG. 1 is a schematic structural diagram of a low-disturbance hole-forming device provided in an embodiment of the present invention; FIG. 2 is a cross-sectional structural schematic diagram along the letter A-A line in FIG. 1 . As shown in FIGS. 1 and 2 , the low-disturbance hole-forming device provided in the embodiment of the present invention includes: a multi-section hollow outer drill pipe 1 that can be connected to each other, and a hole-forming drill bit 2 is installed at one end of the outer drill pipe 1 (made of diamond); the inner drill rod 3, the inner drill rod 3 is installed in the outer drill rod 1, and the inner drill rod 3 can rotate along the axis line of the outer drill rod 1, and the inner drill rod 3 is arranged along the inner drill rod The length direction of 3 is provided with a water flow channel 4, and the inner drill rod 3 is provided with a helical fin 5; There is a water outlet hole 7 on it, and the water outlet hole 7 communicates with the water flow channel 4 .

In the present invention, a rod tail joint can be installed on the inner drill pipe 3, so as to use the rod tail joint to supply water to the water flow channel 4 in the inner drill rod 3 and also provide a force application point for the driving equipment.

In the present invention, when the outer drill pipe 1 and the inner drill pipe 3 are driven by the corresponding driving equipment and rotate in the opposite direction, the hole can be drilled. The slag is flushed out of the outer drill pipe 1 .

In the present invention, when the hole-forming drill bit 2 and the crushing drill bit 6 are drilled into a hole, the water flowing through the water flow channel 4 and the water outlet hole 7 in turn cools the drill bit, and after cooling, the water flows out through the gap between the outer drill pipe 1 and the inner drill pipe 3, Compared with the traditional water flow flushing and slag discharge method, the above cooling method can prevent the problem of strength reduction or even softening and collapse of the surrounding rock in the hole wall due to a large amount of water immersion.

Specifically, in the present invention, one end of the outer drill rod 1 is provided with a first threaded joint 9 , and the other end of the outer drill rod 1 is provided with a second threaded joint 10 . The above-mentioned threaded joints can be used on the outer drill rod 1, and the upper and lower adjacent outer drill rods 1 can be used for mutual continuity, so as to meet the needs of different drilling depths.

Specifically, the hole forming device in the present invention further includes a plurality of support rods 11 and a plurality of support bearings 12. In the present invention, the support bearings 12 (which can be conical bearings) are installed on the inner drill rod 3 at intervals, and one end of the support rod 11 is installed On the inner wall of the outer drill rod 1 , the other end of the support rod 11 extends and is connected to the bearing outer ring of the support bearing 12 .

On the basis of the above technical solutions, further, in the low-disturbance hole forming device provided in this embodiment, the crushing bit 6 is further provided with multiple spiral grooves 8 to utilize crushed mudstone.

In the present invention, the method for forming holes using the above-mentioned low-disturbance hole forming device is:

S1. Connect several extra-section drill pipes 1 according to the depth requirements;

S2, inject cooling water into the water flow channel 4, so that the water flow flows out through the water flow channel 4 and the water outlet in turn, thereby cooling the hole forming drill bit 2 and the crushing drill bit 6;

S3. Drive the outer drill pipe 1 and the inner drill pipe 3 respectively to make them rotate in the opposite direction, so as to use the hole-forming drill bit 2 to rotate to break the rock and drill into the hole, and at the same time use the reverse rotation of the helical fin 5 to break the broken mudstone The rock slag rushes out of the outer drill pipe 1;

S4. Drill to the design depth.

The above are only preferred embodiments of the present invention, and are not intended to limit the embodiments and protection scope of the present invention. For those skilled in the art, they should be aware of the equivalent replacement and Solutions obtained by obvious changes shall all be included in the protection scope of the present invention.

Claims (7)

1. A low disturbance pore-forming device in soft mudstone stock/cable hole, characterized by that, includes:

the drilling machine comprises a plurality of hollow outer drill rods (1) which can be connected with each other, wherein a pore-forming drill bit (2) is arranged at one end of each outer drill rod (1);

the inner drill rod (3) is installed in the outer drill rod (1), the inner drill rod (3) can rotate along the axial lead of the outer drill rod (1), a water flow channel (4) is arranged in the inner drill rod (3) along the length direction of the inner drill rod (3), and a spiral wing plate (5) is arranged on the inner drill rod (3); and

broken drill bit (6), broken drill bit (6) install in interior drilling rod (3) are close to relatively one of pore-forming drill bit (2) is served, just be equipped with apopore (7) on broken drill bit (6), apopore (7) with rivers passageway (4) intercommunication.

2. A low-disturbance hole-forming device according to claim 1, characterized in that a plurality of spiral grooves (8) are further formed on the crushing drill bit (6).

3. A low-disturbance hole-forming device according to claim 1 or 2, characterized in that one end of the outer drill rod (1) is provided with a first threaded joint (9), the other end of the outer drill rod (1) is provided with a second threaded joint (10), and the hole-forming drill bit (2) is screwed on the outer drill rod (1) through the first threaded joint (9).

4. The low-disturbance hole forming device according to claim 3, further comprising a plurality of support rods (11) and a plurality of support bearings (12), wherein the support bearings (12) are installed on the inner drill rod (3) at intervals, one end of each support rod (11) is installed on the inner wall of the outer drill rod (1), and the other end of each support rod (11) extends and is connected to a bearing outer ring of the support bearing (12).

5. A low-disturbance hole-forming device according to claim 4, characterized in that the support bearing (12) is a conical bearing.

6. A low-disturbance hole-forming device according to claim 4 or 5, characterized in that the hole-forming drill (2) is made of diamond.

7. A method of forming a hole using the low-disturbance hole forming device of any one of claims 1-6, comprising the steps of:

s1, connecting a plurality of outer drill rods (1) according to the drilling depth requirement;

s2, injecting cooling water into the water flow channel (4) to enable the water flow to flow out through the water flow channel (4) and the water outlet in sequence, so as to cool the hole-forming drill bit (2) and the crushing drill bit (6);

s3, the outer drill rod (1) and the inner drill rod (3) are driven to rotate in opposite directions respectively, so that the hole forming drill bit (2) is used for breaking rock and drilling holes, and broken mudstone and rock residues are flushed out of the outer drill rod (1) by means of the reverse rotation action of the spiral wing (5) at the same time;

and S4, drilling to the designed depth.

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