A roller cone drill bit

Abstract

The utility model discloses a roller cylinder drill bit, including the drill cylinder and a plurality of bottom roller, the top of drill cylinder is equipped with the square head of drilling equipment, each bottom roller is arranged in the lower edge of drill cylinder and evenly distributes along the circumference of drill cylinder, wherein a part of bottom roller's tooth surface is inward, the tooth surface of remaining bottom roller is outward, its characterized in that: still include at least two inner wall tooth, and the inner wall tooth is arranged in the upper portion of drill cylinder inner wall. This roller cylinder drill bit can polish the rock column that the rock layer with higher hardness is twisted off successfully when drilling, and effectively guarantees the smooth progress of drilling.

Description

Technical Field

[0001] This utility model relates to the field of construction equipment technology, and in particular to a roller cone drill bit. Background Technology

[0002] Rotary cone drill bits, as a highly efficient rock-breaking tool, are widely used in geological exploration, pile foundation construction, and rock mining. When rotary drilling rigs encounter interlayers, boulders, or rock formations during excavation, they can use rotary cone drill bits instead of conventional borehole drill bits to continue drilling. During operation, the roller cones at the lower edge of the drill barrel shear and scrape the rock strata, breaking them into cylindrical stone pillars that can extend into the drill barrel. Once the stone pillar reaches the top of the drill barrel, the drill barrel presses against the top of the stone pillar and begins to twist. The friction between the top of the drill barrel and the stone pillar breaks the stone pillar. Finally, the drill barrel and the stone pillar are lifted together and the stone pillar is discharged. This process is repeated.

[0003] Because the breaking of a stone pillar relies on the friction between the drill barrel and the stone pillar, as disclosed in CN116717205A, a core drill bit that can flush the bottom of the hole can generate a tangential shearing force on the root of the stone pillar when the drill barrel rotates during drilling, thereby breaking the stone pillar; however, when facing rock strata with high hardness, it is difficult to fix the stone pillar by relying solely on the friction between the drill barrel and the stone pillar. The drill barrel is prone to slippage when rotating, making it impossible to break the stone pillar and causing the drilling to stop. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a roller cone drill bit that can smoothly grind hard rock layers into stone pillars and twist them off during drilling, effectively ensuring the smooth progress of drilling.

[0005] To solve the above technical problems, the following technical solution is adopted:

[0006] A roller cone drill bit includes a drill barrel and a plurality of bottom roller cones. The top of the drill barrel is provided with a drill tool square head. Each bottom roller cone is respectively disposed on the lower edge of the drill barrel and evenly distributed along the circumference of the drill barrel. The tooth surfaces of some bottom roller cones face inward, and the tooth surfaces of the remaining bottom roller cones face outward. The bit bit is characterized in that it also includes at least two inner wall roller cones, which are disposed on the upper part of the inner wall of the drill barrel.

[0007] When the aforementioned roller cone drill bit is in operation, the drill barrel is connected to the drilling rig via the drill bit square head. The drilling rig drives the drill barrel to drill underground and rotate. The bottom roller cones scrape and grind the rock strata into a stone column from both the inside and outside. When the stone column extends into the upper part of the drill barrel, the upper end of the stone column can contact the inner roller cones. At this time, the inner roller cones hold the upper end of the stone column from the side. As the drill barrel continues to rotate, the base of the stone column will be subjected to shearing force due to the rotation of the drill barrel, and under the action of grinding, it will be twisted off. At this time, the twisted stone column can be easily pulled out. This roller cone drill bit can hold the upper end of the stone column from the side during drilling, fix the stone column, and make the stone column easily twisted off. This ensures that the roller cone drill bit can still complete the grinding and scraping of the rock strata and the twisting off of the stone column when facing hard rock strata, effectively ensuring the continuous drilling.

[0008] In the preferred embodiment, the number of bottom rollers with inward-facing tooth surfaces is the same as the number of bottom rollers with outward-facing tooth surfaces, and they are alternately distributed in the circumferential direction of the drill barrel.

[0009] In a preferred embodiment, the roller cone drill bit further includes a hard rock cutting tooth, which is detachably installed on the lower part of the inner wall of the drill barrel, with the hard rock cutting tooth facing inward. When encountering stone pillars with extremely high hardness that cannot be broken by rotating the drill barrel, the roller cone drill bit is first lifted, then the hard rock cutting tooth is installed on the lower part of the inner wall of the drill barrel, and then the roller cone drill bit is pressed down, so that the hard rock cutting tooth enters the gap between the stone pillar and the inner wall of the hole. The hard rock cutting tooth can hold the stone pillar from the side, and under the pushing force of the hard rock cutting tooth, the part of the stone pillar inside the drill barrel will gradually tilt until the root of the stone pillar is cut off. As the cut-off stone pillar gradually extends into the drill barrel, when the hard rock cutting tooth passes the root of the stone pillar, the hard rock cutting tooth and the drill barrel together fix the stone pillar. At this time, the roller cone drill bit can be lifted and the stone pillar can be removed. By setting hard rock cutting teeth, it is possible to further cut off rock columns with even higher hardness, ensuring that the roller cone drill bit can successfully drill holes when facing rock layers of different hardness.

[0010] In a further preferred embodiment, a cutting tooth holder is provided on the inner wall of the drill barrel, and the hard rock cutting tooth is detachably mounted on the cutting tooth holder. Typically, the inner end of the cutting tooth holder has a mounting groove, and the outer end of the cutting tooth holder has a through hole communicating with the mounting groove (the drill barrel also has a corresponding communicating hole). The hard rock cutting tooth is installed into the mounting groove of the cutting tooth holder by hammering, and during disassembly, the hard rock cutting tooth is knocked out of the cutting tooth holder in the opposite direction through the through hole.

[0011] In a further preferred embodiment, the distance between the hard rock cutting tooth and the lower edge of the drill barrel is 100mm.

[0012] In the preferred embodiment, there are two inner wall rollers, which are symmetrically arranged on the left and right sides. When the stone column extends into the drill barrel and comes into contact with the inner wall rollers, the inner wall rollers can hold the stone column in place from both sides.

[0013] In a preferred embodiment, the distance between the inner wall roller cone and the top of the drill barrel is 300mm.

[0014] In a preferred embodiment, the lower edge of the drill barrel is further provided with two scraper blocks, which are symmetrically arranged on the left and right sides and positioned between two adjacent bottom rollers. The scraper blocks can scrape away the powder scraped off by the bottom rollers during drilling.

[0015] In a preferred embodiment, the rotary drill bit further includes helical ribs, which are spirally wound around the outer wall of the drill barrel along its length. Typically, the helical ribs are welded onto the outer wall of the drill barrel. The helical ribs enhance the overall rigidity and deformation resistance of the drill barrel, ensuring construction accuracy and extending service life. They effectively distribute stress on the rotary drill bit, reduce deformation, and improve its durability and reliability.

[0016] The beneficial effects of this utility model are that this roller cone drill bit can smoothly grind hard rock layers into stone pillars and twist them off during drilling, effectively ensuring the continuous drilling process. Attached Figure Description

[0017] Figure 1 This is a sectional view of the roller cone drill bit along the longitudinal section of the drill barrel in an embodiment of this utility model;

[0018] Figure 2 This is a schematic diagram of the structure of the roller cone drill bit in the embodiment of this utility model;

[0019] Figure 3 This is a cross-sectional view of the roller cone drill bit along the cross-section of the drill barrel in an embodiment of this utility model. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0021] like Figure 1-3 The drill bit shown includes a drill barrel 1, two inner wall roller cones 2, and multiple bottom roller cones 3. The top of the drill barrel 1 is provided with a drill tool square head 101. Each bottom roller cone 3 is respectively arranged on the lower edge of the drill barrel 1 and evenly distributed along the circumference of the drill barrel 1. Some of the bottom roller cones 3 have their tooth surfaces facing inward, while the tooth surfaces of the remaining bottom roller cones 3 face outward. The number of bottom roller cones 3 with their tooth surfaces facing inward is the same as the number of bottom roller cones 3 with their tooth surfaces facing outward, and they are alternately distributed along the circumference of the drill barrel 1. The two inner wall roller cones 2 are arranged on the upper part of the inner wall of the drill barrel 1, and the two inner wall roller cones 2 are arranged symmetrically from left to right.

[0022] When the aforementioned roller cone drill bit is in operation, the drill barrel 1 is connected to the drilling rig via the drill bit square head 101. The drilling rig drives the drill barrel 1 to drill underground and rotate. The bottom roller cones 3 can scrape and grind the rock strata into a stone column from both the inside and outside. When the stone column extends into the upper part of the drill barrel 1, the upper end of the stone column can contact the inner roller cones 2. At this time, the inner roller cones 2 hold the upper end of the stone column from both sides. As the drill barrel 1 continues to rotate, the root of the stone column will be subjected to shearing force due to the rotation of the drill barrel 1, and will be twisted off under the action of grinding. At this time, the twisted stone column can be successfully pulled out. This roller cone drill bit can hold the upper end of the stone column from the side during drilling, fix the stone column, and make the stone column easily twisted off. This ensures that the roller cone drill bit can still complete the grinding and scraping of the rock strata and the twisting off of the stone column when facing hard rock strata, effectively ensuring the continuous drilling.

[0023] The roller cone drill bit also includes a hard rock cutting tooth 4, which is detachably installed on the lower part of the inner wall of the drill barrel 1, with the hard rock cutting tooth 4 facing inward. When encountering a stone column with extremely high hardness that cannot be broken by rotating the drill barrel 1, the roller cone drill bit is first lifted, and then the hard rock cutting tooth 4 is installed on the lower part of the inner wall of the drill barrel 1. The roller cone drill bit is then pressed down, so that the hard rock cutting tooth 4 enters the gap between the stone column and the inner wall of the hole. The hard rock cutting tooth 4 can hold the stone column from the side. Under the pushing force of the hard rock cutting tooth 4, the part of the stone column inside the drill barrel 1 will gradually tilt until the root of the stone column is cut off. As the cut-off stone column gradually extends into the drill barrel 1, when the hard rock cutting tooth 4 passes the root of the stone column, the hard rock cutting tooth 4 and the drill barrel 1 together fix the stone column. At this time, the roller cone drill bit can be lifted and the stone column can be removed. By setting the hard rock cutting tooth 4, it is possible to further cut off rock columns with even higher hardness, ensuring that the roller cone drill bit can successfully drill holes when facing rock layers of different hardness.

[0024] The inner wall of the drill barrel 1 is provided with a cutting tooth holder for installing the hard rock cutting tooth 4. The hard rock cutting tooth 4 is installed into the cutting tooth holder by hammering.

[0025] The distance between the hard rock cutting tooth 4 and the lower edge of the drill barrel 1 is 100mm; the distance between the inner wall roller cone 2 and the top of the drill barrel 1 is 300mm.

[0026] Two scraper blocks 102 are also provided on the lower edge of the drill barrel 1. The two scraper blocks 102 are arranged symmetrically on the left and right sides, and the scraper blocks 102 are located between two adjacent bottom rollers 3. The scraper blocks 102 can scrape away the powder scraped off by the bottom rollers 3 during drilling.

[0027] The rotary drill bit also includes helical ribs 5, which are spirally wound around the outer wall of the drill barrel 1 along its length. Typically, the helical ribs 5 are welded onto the outer wall of the drill barrel 1. The helical ribs 5 enhance the overall rigidity and deformation resistance of the drill barrel 1, ensuring construction accuracy and extending its service life. They effectively distribute the stress on the rotary drill bit, reduce deformation, and improve its durability and reliability.

Claims

1. A roller cone drill bit, comprising a drill barrel and a plurality of bottom roller cones, wherein a drill bit square head is provided at the top of the drill barrel; each bottom roller cone is respectively disposed on the lower edge of the drill barrel and evenly distributed along the circumference of the drill barrel, wherein the tooth surfaces of a portion of the bottom roller cones face inward, and the tooth surfaces of the remaining bottom roller cones face outward, characterized in that: It also includes hard rock cutting teeth and at least two inner wall rollers, the inner wall rollers being disposed on the upper part of the inner wall of the drill barrel; the hard rock cutting teeth are detachably mounted on the lower part of the inner wall of the drill barrel, and the hard rock cutting teeth face inward.

2. The roller cone drill bit as described in claim 1, characterized in that: The number of bottom cones with inward-facing teeth is the same as the number of bottom cones with outward-facing teeth, and they are alternately distributed around the circumference of the drill barrel.

3. A roller cone drill bit as described in claim 1, characterized in that: The inner wall of the drill barrel is provided with a cutting tooth holder, and the hard rock cutting tooth can be detachably installed on the cutting tooth holder.

4. A roller cone drill bit as described in claim 1, characterized in that: The distance between the hard rock cutting tooth and the lower edge of the drill barrel is 100mm.

5. A roller cone drill bit as described in claim 1, characterized in that: The number of inner wall rollers is two, and the two inner wall rollers are arranged symmetrically on the left and right.

6. A roller cone drill bit as described in claim 1, characterized in that: The distance between the inner wall roller cone and the top of the drill barrel is 300mm.

7. A roller cone drill bit as described in claim 1, characterized in that: The lower edge of the drill barrel is also provided with two slag scraping blocks, which are symmetrically arranged on the left and right, and the slag scraping blocks are located between two adjacent bottom roller cones.

8. A roller cone drill bit as described in claim 1, characterized in that: The roller cone drill bit also includes helical ribs, which are spirally wound around the outer wall of the drill barrel along its length.

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