A drill bit structure suitable for soft rock drilling in western regions

Abstract

The application provides a drill bit structure suitable for soft rock drilling in western regions, which comprises a drill bit body; the working end of the drill bit body is shaped as a concave structure, and the inside of the concave structure is provided with a 'cone' shaped cutter head, the 'cone' shaped cutter head is provided with a first hob, and the outer edge of the concave structure is provided with a ring-shaped flat bottom cutter head along the ring direction, the ring-shaped flat bottom cutter head is provided with a second hob. The application has the advantages that the drill bit structure is simple in structure and convenient to use; during construction, the second hob on the ring-shaped flat bottom cutter head first breaks rock in advance to form an advanced ring-shaped cutting groove with a certain depth, then the first hob on the 'cone' shaped cutter head continues to cut to form a conical rock column, wherein the advanced rock breaking of the second hob can play a role in stabilizing the drilling tool and guiding, and at the same time, a free surface is formed for the rock column in the ring-shaped cutting groove when it is broken, so as to improve the construction efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of drilling method shaft sinking construction, and particularly relates to a drill bit structure suitable for soft rock drilling in western regions. BACKGROUND

[0002] Drilling method shaft sinking is a safe and reliable, low-cost and high-quality coal mine shaft construction method, which has the following characteristics: (1) mechanized shaft sinking, ground operation, safe and reliable, less labor, and good operation environment; (2) the shaft lining is prefabricated and maintained on the ground, and compared with other construction methods, the quality of shaft lining prefabrication and maintenance is guaranteed; (3) the entire shaft sinking process does not require toxic and harmful gases and dangerous explosives, and is safe and reliable.

[0003] At present, drilling method construction technology has made great progress, but there are still disadvantages such as low drilling efficiency and long construction period in large-diameter hole type and rock stratum drilling construction, especially in the drilling of mudstone and argillaceous siltstone in the Jurassic system in western regions of China. The efficiency is very low. However, the western region is the current key area of coal mining in China, and therefore, how to improve the drilling method construction efficiency in the western region has become the research focus of drillers.

[0004] Through research and analysis, it is found that whether the drill bit structure is reasonable is the most important factor affecting the drilling efficiency in the western region. Therefore, the drilling efficiency of soft rock drilling construction in the western region can be further improved by improving the drill bit structure. SUMMARY

[0005] The present application relates to the field of drilling method shaft sinking construction, and particularly relates to a drill bit structure suitable for soft rock drilling in western regions.

[0006] The present application solves the above technical problems by adopting the following technical solutions:

[0007] A drill bit structure suitable for soft rock drilling in western regions, comprising a drill bit body; the working end of the drill bit body is shaped as a concave structure, and the inside of the concave structure is provided with a "cone" shaped cutter head, a first rolling cutter is installed on the "cone" shaped cutter head, and a ring-shaped flat bottom cutter head is provided on the outer edge of the concave structure along the ring direction, and a second rolling cutter is installed on the ring-shaped flat bottom cutter head.

[0008] Here, the concave structure design of the drill bit body working end, that is, the leading middle "cone" shaped cutter disc of the outer edge ring-shaped flat bottom cutter disc, can make the second rolling cutter on the ring-shaped flat bottom cutter disc break rock in advance to form an advanced ring-shaped cutting groove with a certain depth, and the first rolling cutter on the "cone" shaped cutter disc cuts to form a conical rock pillar. Among them, the advanced rock breaking of the second rolling cutter on the ring-shaped flat bottom cutter disc can play a role in stabilizing the drilling tool and guiding, and at the same time, a free surface is formed when the rock pillar in the ring-shaped cutting groove is broken. The conical design of the "cone" shaped cutter disc is to facilitate the rock breaking of the rolling cutter and the flow of the supplementary slurry in the later period.

[0009] As one of the preferred modes of the present application, the ring-shaped flat bottom cutter disc is further provided with a drill sludge side absorption pipe; one end of the drill sludge side absorption pipe is connected with the ring-shaped flat bottom cutter disc, and extends downward through the ring-shaped flat bottom cutter disc, and the other end of the drill sludge side absorption pipe is connected with the central pipe collection absorption pipe inside the drill bit body. Among them, the design of the drill sludge side absorption pipe is to absorb the drill sludge upward during drilling.

[0010] As one of the preferred modes of the present application, the drill sludge side absorption pipe is provided with a plurality of; the plurality of drill sludge side absorption pipes are arranged at equal intervals on the disc body of the ring-shaped flat bottom cutter disc; wherein the arrangement of the plurality of drill sludge side absorption pipes realizes multi-point absorption, avoids the easy tooth paste phenomenon caused by excessive concentration of concentrated absorption of drill sludge, thereby facilitating the rolling cutter to maintain sharp cutting edge to break rock efficiently.

[0011] As one of the preferred modes of the present application, the drill sludge side absorption pipe and the central pipe collection absorption pipe constitute a drill sludge discharge channel.

[0012] As one of the preferred modes of the present application, the "cone" shaped cutter disc is further provided with an inclined supplementary slurry pipe; one end of the inclined supplementary slurry pipe is connected with the "cone" shaped cutter disc, and communicates with the inside of the concave structure through the "cone" shaped cutter disc, and the other end of the inclined supplementary slurry pipe communicates with the outside. Among them, the design of the inclined supplementary slurry pipe is to guide the mud to the center of the bottom of the drill bit; during drilling construction, the supplementary slurry directly flushes the upper part of the conical rock pillar in the middle of the hole bottom, and then flows downward along the inclined surface of the conical rock pillar to the ring-shaped cutting groove. Under the action of the gravity of the mud, this flow direction is more conducive to the flow of the mud, thereby enhancing the ability of the mud to carry the drill sludge.

[0013] As one of the preferred modes of the present application, the inclined supplementary slurry pipe constitutes an entering channel of the cutting flushing mud.

[0014] As one of the preferred modes of the present application, the drill bit body is further provided with a drill bit connecting flange, a bearing cylinder, an outer cylinder and a disc; wherein the drill bit connecting flange is located at the top, the drill bit body is connected with the drilling tool system above it through the drill bit connecting flange; the bearing cylinder and the outer cylinder are located below the drill bit connecting flange and connected with it respectively, and the outer cylinder below the bearing cylinder is internally provided with the disc transversely; the middle part of the disc is connected with the "cone" shaped cutter, and the bottom of the outer cylinder is connected with the annular flat bottom cutter.

[0015] As one of the preferred modes of the present application, the drill bit body between the drill bit connecting flange and the disc is further provided with an inner rib plate and an outer rib plate; the drill bit connecting flange, the inner rib plate, the bearing cylinder, the outer rib plate, the disc, the outer cylinder, the "cone" shaped cutter and the annular flat bottom cutter jointly constitute a complete force-bearing drill bit body.

[0016] The present application has the advantages over the prior art that: the present application is designed according to the drilling and slag removal principle of large vertical shaft drilling machine and the geological characteristics of soft rock in western region (especially the middle mudstone of Jurassic system); the drill bit structure of the present application is simple and convenient to use; during construction, the second roller cutter on the annular flat bottom cutter first breaks the rock in advance to form an advanced annular cutting groove with a certain depth, then the first roller cutter on the "cone" shaped cutter continues to cut to form a conical rock pillar; wherein the advanced rock breaking of the second roller cutter can play a role in stabilizing the drilling tool and guiding, and at the same time, a free surface is formed for the rock pillar in the annular cutting groove when it is broken, thereby improving the construction efficiency; and during the construction process, the slurry is released to the conical rock pillar through the oblique grouting pipe to flush the rock pillar, and the mixed slurry and drilling slag are discharged through the drilling slag side suction pipe. BRIEF DESCRIPTION OF DRAWINGS

[0017] Fig. 1 is the bottom structure diagram of the drill bit structure suitable for soft rock drilling in western region in example 1;

[0018] Fig. 2 is the front view cut structure diagram of the drill bit structure suitable for soft rock drilling in western region in example 1;

[0019] Fig. 3 is the structure diagram of the drilled rock layer after cutting of the drill bit structure in example 1.

[0020] In the figure: 1 is the drill bit body, 11 is the concave structure, 12 is the "cone" shaped cutter, 121 is the first roller cutter, 122 is the oblique grouting pipe, 13 is the annular flat bottom cutter, 131 is the second roller cutter, 132 is the drilling slag side suction pipe, 133 is the central pipe collection suction pipe, 14 is the drill bit connecting flange, 15 is the bearing cylinder, 16 is the outer cylinder, 17 is the disc, 18 is the inner rib plate, 19 is the outer rib plate, 2 is the annular cutting groove, and 3 is the conical rock pillar. Detailed Implementation

[0021] The embodiments of the present invention are described in detail below. These embodiments are implemented based on the technical solution of the present invention, and provide detailed implementation methods and specific operation processes. However, the scope of protection of the present invention is not limited to the following embodiments.

[0022] Example 1

[0023] like Figs. 1-3 As shown, this embodiment of a drill bit structure suitable for drilling soft rock in western regions includes a drill bit body 1; the working end of the drill bit body 1 is formed into a concave structure 11, and a conical cutter head 12 is provided inside the concave structure. A first roller cutter 121 is installed on the conical cutter head 12, and a circumferential flat-bottomed cutter head 13 is provided along the outer edge of the concave structure 11, and a second roller cutter 131 is installed on the circumferential flat-bottomed cutter head 13.

[0024] Here, the concave structure 11 at the working end of the drill bit body 1, where the outer edge of the circumferential flat-bottomed cutterhead 13 precedes the central "conical" cutterhead 12, allows the second roller cutter 131 on the circumferential flat-bottomed cutterhead 13 to break the rock ahead of the drill bit during construction, forming a leading circumferential cutting groove 2 of a certain depth. Meanwhile, the first roller cutter 121 on the "conical" cutterhead 12 cuts later, forming a conical rock column 3. The leading rock breaking by the second roller cutter 131 on the circumferential flat-bottomed cutterhead 13 stabilizes the drill bit and provides guidance, while also creating a free surface for the rock column within the circumferential cutting groove 2 during breakage. The conical design of the "conical" cutterhead 12 facilitates rock breaking by the roller cutter and the flow of subsequent mud filling.

[0025] Specifically, in this embodiment, a cuttings-side absorption pipe 132 is also provided on the circumferential flat-bottom cutterhead 13; one end of the cuttings-side absorption pipe 132 is connected to the circumferential flat-bottom cutterhead 13 and extends downward through the circumferential flat-bottom cutterhead 13, and the other end of the cuttings-side absorption pipe 132 is connected to the central tube collection absorption pipe 133 inside the drill bit body 1. The cuttings-side absorption pipe 132 and the central tube collection absorption pipe 133 constitute a cuttings discharge channel, and their design is to absorb cuttings upwards during the drilling process.

[0026] Furthermore, in order to achieve multi-point absorption and avoid the problem of easy tooth jamming caused by excessive concentration of drill cuttings, thereby helping the cutter to maintain a sharp cutting edge and efficiently break rocks, multiple drill cuttings side absorption pipes 132 are provided, and the multiple drill cuttings side absorption pipes 132 are designed to be arranged in an evenly spaced circular pattern on the disc body of the circumferential flat-bottom cutterhead 13.

[0027] Specifically, in the embodiment, the "cone" shaped cutter head 12 is further provided with a slanting supplementary mud pipe 122, one end of the slanting supplementary mud pipe 122 is connected with the "cone" shaped cutter head 12 and penetrates the "cone" shaped cutter head 12 to communicate with the inside of the concave structure 11, and the other end of the slanting supplementary mud pipe 122 communicates with the outside. The slanting supplementary mud pipe 122 constitutes an entering channel for cutting and flushing mud, and is designed to guide the mud to the bottom center of the drill bit. During drilling construction, the supplementary mud directly flushes the upper part of the conical rock column 3 in the middle of the hole bottom, and then flows downward along the inclined surface of the conical rock column 3 into the annular cutting groove 2. Under the action of the gravity of the mud, this flow direction is more conducive to the flow of the mud, thereby enhancing the ability of the mud to carry drill cuttings.

[0028] In addition, in the embodiment, the drill bit body 1 is further provided with a drill bit connecting flange 14, a bearing cylinder 15, an outer cylinder 16 and a disc 17. The drill bit connecting flange is located at the topmost part, and the drill bit body is connected with the drilling tool system above it through the drill bit connecting flange; the bearing cylinder and the outer cylinder are located below the drill bit connecting flange and are connected with it respectively, and the outer cylinder inside below the bearing cylinder is transversely provided with the disc; the middle part of the disc is connected with the above-mentioned "cone" shaped cutter head, and the bottom of the outer cylinder is connected with the above-mentioned annular flat-bottomed cutter head. At the same time, the drill bit body between the drill bit connecting flange and the disc is further provided with an inner rib plate 18 and an outer rib plate 19; in the embodiment, the drill bit connecting flange 14, the inner rib plate 18, the bearing cylinder 15, the outer rib plate 19, the disc 17, the outer cylinder 16, the "cone" shaped cutter head 12 and the annular flat-bottomed cutter head 13 jointly constitute a complete force-bearing drill bit body.

[0029] The drill bit structure of the embodiment is simple in structure and convenient to use; during construction, the second roller cutter 131 on the annular flat-bottomed cutter head 13 first breaks the rock in advance to form an advanced annular cutting groove 2 with a certain depth, and then the first roller cutter 121 on the "cone" shaped cutter head 12 continues to cut to form a conical rock column 3; and during the construction process, the slanting supplementary mud pipe 122 releases mud to flush the conical rock column 3, and the mud mixed with the drill cuttings is discharged upward through the drill cuttings side suction pipe 132 and the central pipe collection suction pipe 133.

[0030] The above only describes the preferred embodiment of the present application and is not intended to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A drill bit structure suitable for drilling soft rock in western China, characterized in that, Includes a drill bit body; the working end of the drill bit body is formed into a concave structure, and a conical cutter head is provided inside the concave structure. A first hob is installed on the conical cutter head. A circumferential flat-bottom cutter head is provided along the outer edge of the concave structure, and a second hob is installed on the circumferential flat-bottom cutter head. The circumferential flat-bottom cutterhead is also provided with a cuttings side absorption pipe; one end of the cuttings side absorption pipe is connected to the circumferential flat-bottom cutterhead and extends downward through the circumferential flat-bottom cutterhead, and the other end of the cuttings side absorption pipe is connected to the central tube collection absorption pipe inside the drill bit body. The cone-shaped cutterhead is also equipped with an inclined grouting pipe; one end of the inclined grouting pipe is connected to the cone-shaped cutterhead and passes through the cone-shaped cutterhead to connect with the interior of the concave structure, while the other end of the inclined grouting pipe is connected to the outside; the inclined grouting pipe constitutes the entry channel for cutting and flushing mud; during drilling, the replenished grout directly flushes the upper part of the cone-shaped rock column in the middle of the bottom of the hole, and then flows down along the inclined surface of the cone-shaped rock column into the circumferential cutting groove; Multiple cuttings side absorption pipes are provided; the multiple cuttings side absorption pipes are arranged in an equally spaced circular pattern on the disc body of the circumferential flat-bottom cutterhead.

2. The drill bit structure for soft rock drilling in western regions according to claim 1, characterized in that, The cuttings side absorption pipe and the central pipe combined absorption pipe form a cuttings discharge channel.

3. The drill bit structure for soft rock drilling in western regions according to claim 1, characterized in that, The drill bit body is also provided with a drill bit connecting flange, a support cylinder, an outer cylinder, and a disc; wherein, the drill bit connecting flange is located at the top, and the drill bit body is connected to the drilling tool system above it through the drill bit connecting flange; the support cylinder and the outer cylinder are located below the drill bit connecting flange and are respectively connected to it; at the same time, the disc is horizontally arranged inside the outer cylinder located below the support cylinder; the "cone" shaped cutter head is connected to the middle of the disc, and the circumferential flat-bottom cutter head is connected to the bottom of the outer cylinder.

4. The drill bit structure for soft rock drilling in western regions according to claim 3, characterized in that, The drill bit body between the drill bit connecting flange and the disc is also provided with inner stiffening plates and outer stiffening plates; the drill bit connecting flange, inner stiffening plates, bearing cylinder, outer stiffening plates, disc, outer cylinder, "cone" shaped cutter head, and circumferential flat bottom cutter head together constitute a complete load-bearing drill bit body.

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