A three-wing drill bit capable of drilling soft rock

Abstract

This utility model relates to a three-wing drill bit capable of drilling soft rock, comprising a support assembly and a drilling assembly. The support assembly includes a support body and a gauge bar. The support body is threadedly connected to an external drill rod. A water inlet hole is provided in the center of the support body. Three gauge bars are arranged circumferentially and are respectively fixed to the edge of the support body. The drilling assembly includes an edge rock-breaking column and a central rock-breaking column. The edge rock-breaking column is fixed to the gauge bar, and the central rock-breaking column is fixed to the center of the support body. An outward swing angle is provided between the edge rock-breaking column and the support body. When the drill bit rotates at high speed, the cutting edge of the edge rock-breaking column can expand the borehole diameter, that is, the edge cutting linear velocity of the edge rock-breaking column increases, which can throw the drill cuttings attached to the surface of the drill bit out at high speed.

Description

Technical Field

[0001] This utility model belongs to the field of drill bit design technology, and specifically relates to a three-wing drill bit that can drill soft rock. Background Technology

[0002] The three-wing drill bit is a multi-cutting-edge drilling tool mainly used for rapid drilling in soft to medium-hard formations. It features high chip removal efficiency and low torque, and is widely used in geological exploration, oil drilling, civil engineering and other fields.

[0003] However, in drilling operations in softer rock formations, the drill bit often gets stuck and clogged. This can cause the cooling water to fail to cool the drill bit effectively and in a timely manner, which can easily lead to drill burn-out, large-scale detachment of the composite plates on the drill bit end face, and render the drill bit unusable. The drill bit needs to be replaced periodically, which is costly and inefficient.

[0004] Therefore, there is an urgent need for a three-wing drill bit capable of drilling soft rock to solve the above problems. Utility Model Content

[0005] To achieve the above objectives, this utility model provides the following technical solution: a three-wing drill bit capable of drilling soft rock, comprising: a support assembly and a drilling assembly; the support assembly includes a support body and a gauge bar; the support body is threadedly connected to an external drill rod; a water inlet hole is provided in the center of the support body; three gauge bars are arranged circumferentially and are respectively fixed to the edge of the support body; the drilling assembly includes an edge rock-breaking column and a central rock-breaking column; the edge rock-breaking column is fixed on the gauge bar; the central rock-breaking column is fixed to the center of the support body; an outward swing angle is provided between the edge rock-breaking column and the support body; when the drill bit rotates at high speed, the cutting edge of the edge rock-breaking column can expand the borehole diameter, that is, the edge cutting linear velocity of the edge rock-breaking column increases, which can throw the drill cuttings attached to the surface of the drill bit out at high speed.

[0006] As a further improvement of this utility model, the outward swing angle between the edge rock-breaking column and the support body is 15°~20°.

[0007] As a further improvement of this utility model, each of the gauge bars has multiple edge rock-breaking columns fixed linearly, and multiple central rock-breaking columns are arranged circumferentially. The cutting surfaces of the multiple edge rock-breaking columns on each gauge bar and the cutting surface of one of the central rock-breaking columns form a continuous cutting surface.

[0008] As a further improvement of this utility model, it also includes an auxiliary centrifugal mechanism, including a connecting pipe and a spiral sleeve. The spiral sleeve is fixed to the outer peripheral wall of the connecting pipe, and a threaded groove that mates with the spiral sleeve is provided on the inner wall of the water inlet. The spiral sleeve is slidably disposed in the threaded groove.

[0009] When the drill bit tip is covered with drill cuttings, the water pressure in the inlet hole drives the spiral sleeve to move rapidly in a spiral motion, and the drill cuttings attached to the connecting pipe are thrown out under the action of centrifugal force.

[0010] As a further improvement of this utility model, an extension ring is fixed on the end peripheral wall of the connecting pipe, and a return spring is provided between the extension ring and the end face of the support body.

[0011] As a further improvement of this utility model, the outer periphery of the spiral sleeve is covered with a rubber layer, and the rubber layer is slidably disposed in the threaded groove.

[0012] As a further improvement of this utility model, a T-shaped groove is provided in the lower end of the extension ring, and a T-shaped block is slidably arranged in the T-shaped groove. The T-shaped block is connected to one end of the reset spring, and the other end of the reset spring is fixedly connected to the end face of the support body.

[0013] As a further improvement of this utility model, the edge of the end face of the support body is provided with a plurality of discharge holes in a circular shape, and the plurality of discharge holes are connected to an external collection device.

[0014] Compared with the prior art, the beneficial effects of this utility model are:

[0015] By setting an edge rock-breaking column with a certain outward swing angle, its cutting edge can rotate at high speed and throw away the soft rock cuttings attached to the end of the drill bit, thus preventing the cuttings from isolating the drill bit from the cooling water.

[0016] By setting up an auxiliary centrifugal mechanism, when drill cuttings enter the concave surface of the drill bit and block the water inlet, the increased water pressure in the water inlet will force the spiral sleeve to move outward from the water inlet. As a result, the spiral sleeve will drive the connecting pipe to move synchronously at high speed. The connecting pipe generates centrifugal force, which can throw away the drill cuttings attached to the concave surface of the drill bit at high speed, thereby keeping the water inlet unobstructed. Therefore, the cooling water always has a certain cooling effect on the end face of the drill bit, preventing the drill bit from overheating and being damaged. Attached Figure Description

[0017] Figure 1 A schematic diagram of a three-wing drill bit capable of drilling soft rock;

[0018] Figure 2 A schematic diagram showing the structural distribution of the auxiliary centrifugal mechanism of a three-wing drill bit capable of drilling soft rock;

[0019] Figure 3 A three-wing drill bit capable of drilling soft rock. Figure 2 Enlarged view of point A in the middle;

[0020] Figure 4 This is a schematic diagram of the spiral sleeve structure of a three-wing drill bit capable of drilling soft rock.

[0021] Among them, 11, support body; 12, gauge bar; 3, water inlet hole; 21, edge rock-breaking column; 22, center rock-breaking column; 41, connecting pipe; 42, spiral sleeve; 31, threaded groove; 411, extension ring; 412, return spring; 111, discharge hole. Detailed Implementation

[0022] See Figures 1 to 4 As shown, a three-wing drill bit capable of drilling soft rock includes a support assembly and a drilling assembly. The support assembly includes a support body 11 and a gauge bar 12. The support body 11 is threaded to an external drill rod. A water inlet hole 3 is provided in the center of the support body 11. Three gauge bars 12 are arranged circumferentially and are respectively fixed to the edge of the support body 11. The drilling assembly includes an edge rock-breaking column 21 and a central rock-breaking column 22. The edge rock-breaking column 21 is fixed to the gauge bar 12, and the central rock-breaking column 22 is fixed to the center of the support body 11. An outward swing angle is provided between the edge rock-breaking column 21 and the support body 11.

[0023] It should be explained that the outer swing angle is the angle between the axis of the cutting surface of the edge rock-breaking column 21 and the axis of the support body 11.

[0024] Specifically, during the high-speed drilling process, the edge rock-breaking column 21 deviates outward at a certain angle, increasing the distance between the cutting edge of the edge rock-breaking column 21 and the axis of the support body 11, thereby expanding the borehole diameter. Moreover, since the angular velocities of the edge rock-breaking column 21 and the support body 11 are equal, the greater the distance between them, the greater the linear velocity. Therefore, the edge rock-breaking column 21 can rotate at high speed and throw away the soft rock cuttings attached to the end of the drill bit, preventing the cuttings from isolating the drill bit from the cooling water.

[0025] In addition, the edge rock-breaking column 21 has an outward swing angle, so the cutting surface of the edge rock-breaking column 21 always remains inclined to the surface to be drilled. The drill cuttings will detach along the inclined cutting surface of the edge rock-breaking column 21, thereby avoiding the accumulation of drill cuttings on the cutting surface.

[0026] In a preferred embodiment, the outward swing angle between the edge rock-breaking column 21 and the support body 11 is 15°~20°.

[0027] For soft rock, if the outward swing angle is less than 15°, the centrifugal force will be insufficient to throw the drill chips attached to the drill bit end face out at high speed. If the outward swing angle is greater than 20°, the cutting edge will become thinner, the impact resistance will decrease, and the tool will easily break.

[0028] In a preferred embodiment, each of the gauge-maintaining bars 12 has a plurality of edge rock-breaking columns 21 linearly fixed on it, and a plurality of central rock-breaking columns 22 are arranged circumferentially. The cutting surfaces of the plurality of edge rock-breaking columns 21 on each of the gauge-maintaining bars 12 and the cutting surface of one of the central rock-breaking columns 22 form a continuous cutting surface.

[0029] In other words, the combined effect of the edge rock-breaking column 21 and the central rock-breaking column 22 can form a complete cylindrical hole, avoiding the need for secondary hole repair.

[0030] In a preferred embodiment, an auxiliary centrifugal mechanism is also included, comprising a connecting pipe 41 and a spiral sleeve 42. The spiral sleeve 42 is fixed to the outer peripheral wall of the connecting pipe 41. A threaded groove 31 that mates with the spiral sleeve 42 is provided on the inner wall of the water inlet 3. The spiral sleeve 42 is slidably disposed in the threaded groove 31.

[0031] If drill cuttings enter the concave surface of the drill bit and block the water inlet hole 3, the connecting pipe 41 will be unable to discharge cooling water normally. At this time, the increased water pressure in the water inlet hole 3 will act on the end of the spiral sleeve 42, forcing the spiral sleeve 42 to move out of the water inlet hole 3. Therefore, the spiral sleeve 42 will move at high speed along the thread groove 31. The spiral sleeve 42 will drive the connecting pipe 41 to move at high speed synchronously. In turn, the connecting pipe 41 will generate centrifugal force of rotation, which can throw away the drill cuttings attached to the concave surface of the drill bit at high speed, so that the water inlet hole 3 remains unobstructed. Therefore, the cooling water always has a certain cooling effect on the end face of the drill bit, avoiding overheating and damage to the drill bit.

[0032] Please note that you should refer to [link / reference]. Figure 3 The lower starting end of the spiral sleeve 42 does not contact the lower starting end of the threaded groove 31, ensuring that water pressure can act on the gap between the spiral sleeve 42 and the threaded groove 31, thereby ensuring that the spiral sleeve 42 can move in a spiral motion.

[0033] In a preferred embodiment, an extension ring 411 is fixed on the end peripheral wall of the connecting pipe 41, and a return spring 412 is provided between the extension ring 411 and the end face of the support body 11.

[0034] When the connecting pipe 41 throws away the drill cuttings at high speed, the water pressure in the water inlet 3 decreases. The return spring 412 will drive the extension ring 411 and the connecting pipe 41 to return to their original positions so that repeated centrifugal motion can be performed to achieve repeated chip removal and ensure that the water inlet 3 remains unobstructed during drilling.

[0035] In a preferred embodiment, a T-shaped groove is provided in the lower end of the extension ring 411, and a T-shaped block is slidably disposed in the T-shaped groove. The T-shaped block is connected to one end of the reset spring 412, and the other end of the reset spring 412 is fixedly connected to the end face of the support body 11.

[0036] In other words, during the high-speed spiral motion of the connecting pipe 41 and the extension ring 411, the return spring 412 and the T-block and the extension ring 411 maintain relative rotation. Therefore, when the extension ring 411 is spiraling, the return spring 412 only extends and contracts in the vertical direction and does not undergo torsional deformation, thus preventing the return spring 412 from deforming and failing.

[0037] In a preferred embodiment, the edge of the end face of the support body 11 is provided with a plurality of discharge holes 111, which are connected to an external collection device.

[0038] The drill cuttings will enter multiple discharge holes 111 and will eventually be collected by external collection equipment.

[0039] Specifically, during high-speed drilling, the drill bit is equipped with an edge rock-breaking column 21 with a certain outward swing angle. Its cutting edge can rotate at high speed and throw away the soft rock cuttings attached to the end of the drill bit, preventing the cuttings from isolating the drill bit from the cooling water. When the cuttings enter the concave surface of the drill bit and block the water inlet 3, the increased water pressure in the water inlet 3 will act on the end of the spiral sleeve 42, forcing the spiral sleeve 42 to move outward from the water inlet 3. Therefore, the spiral sleeve 42 will move at high speed along the thread groove 31. The spiral sleeve 42 will drive the connecting pipe 41 to move at high speed synchronously. In turn, the connecting pipe 41 generates centrifugal force, which can throw away the cuttings attached to the concave surface of the drill bit at high speed, thereby keeping the water inlet 3 unobstructed. Therefore, the cooling water always has a certain cooling effect on the end face of the drill bit, preventing the drill bit from overheating and being damaged. The cuttings after drilling will be discharged through multiple discharge holes 111.

[0040] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be primarily defined by the scope of the claims.

Claims

1. A three-wing drill bit capable of drilling soft rock, characterized in that: include: The support assembly includes a support body (11) and a gauge bar (12). The support body (11) is threaded to an external drill rod. A water inlet hole (3) is provided in the center of the support body (11). Three gauge bars (12) are arranged around the circumference and are fixed to the edge of the support body (11). The drilling assembly includes an edge rock-breaking column (21) and a center rock-breaking column (22). The edge rock-breaking column (21) is fixed on the gauge bar (12), and the center rock-breaking column (22) is fixed at the center of the support body (11). An outward swing angle is provided between the edge rock-breaking column (21) and the support body (11). When the drill bit rotates at high speed, the cutting edge of the edge rock-breaking column (21) can expand the borehole diameter, that is, the edge cutting linear velocity of the edge rock-breaking column (21) increases, which can throw the drill cuttings attached to the surface of the drill bit out at high speed.

2. The three-wing drill bit for drilling soft rock according to claim 1, characterized in that: The outward swing angle between the edge rock-breaking column (21) and the support (11) is 15°~20°.

3. A three-wing drill bit for drilling soft rock according to claim 1, characterized in that: Each of the gauge bars (12) has a plurality of edge rock-breaking columns (21) linearly fixed, and a plurality of central rock-breaking columns (22) are arranged circumferentially. The cutting surfaces of the plurality of edge rock-breaking columns (21) on each of the gauge bars (12) and the cutting surfaces of one of the central rock-breaking columns (22) form a continuous cutting surface.

4. A three-wing drill bit for drilling soft rock according to claim 1, characterized in that: It also includes an auxiliary centrifugal mechanism, including a connecting pipe (41) and a spiral sleeve (42). The spiral sleeve (42) is fixed to the outer peripheral wall of the connecting pipe (41). A threaded groove (31) that mates with the spiral sleeve (42) is provided on the inner wall of the water inlet (3). The spiral sleeve (42) is slidably disposed in the threaded groove (31). When the drill bit tip is covered with drill cuttings, the water pressure in the water inlet (3) pushes the spiral sleeve (42) to move rapidly in a spiral motion, and the drill cuttings attached to the connecting pipe (41) are thrown out under the action of centrifugal force.

5. A three-wing drill bit for drilling soft rock according to claim 4, characterized in that: An extension ring (411) is fixed on the end peripheral wall of the connecting pipe (41), and a return spring (412) is provided between the extension ring (411) and the end face of the support (11).

6. A three-wing drill bit for drilling soft rock according to claim 4, characterized in that: The outer periphery of the spiral sleeve (42) is covered with a rubber layer, which is slidably sealed within the threaded groove (31).

7. A three-wing drill bit for drilling soft rock according to claim 5, characterized in that: The lower end of the extension ring (411) is provided with a T-shaped groove, and a T-shaped block is slidably disposed in the T-shaped groove. The T-shaped block is connected to one end of the reset spring (412), and the other end of the reset spring (412) is fixedly connected to the end face of the support body (11).

8. A three-wing drill bit for drilling soft rock according to claim 1, characterized in that: The support (11) has multiple discharge holes (111) circumferentially opened on the edge of its end face, and the multiple discharge holes (111) are connected to an external collection device.

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