A reaming drill bit capable of preventing drill bit sticking

Abstract

The utility model provides a kind of drill bit of preventing jamming reaming, its technical scheme is: including drill bit body, the drill bit body is divided into drill bit part, reaming part and connecting part, the top of the drill bit part is equipped with a plurality of first abrasive tooth fixedly, the outer wall of reaming part is evenly spaced and is equipped with a plurality of first chip guide groove, the import between adjacent first chip guide groove is equipped with second abrasive tooth fixedly, the export between adjacent first chip guide groove is equipped with third abrasive tooth fixedly, connecting part is connected with drill bit by connecting hole and screw thread connection.The utility model has the beneficial effects that: (1) circular table structure reduces back resistance;(2) slope chip guide groove prevents accumulation;(3) zoning grinding adapts process requirement;(4) chip guide groove and abrasive tooth joint guarantee drill bit;(5) reduce equipment damage, reduce operation and maintenance cost.

Description

Technical Field

[0001] This utility model belongs to the technical field of mining machinery and equipment, and in particular relates to a drill bit for preventing jamming during the retraction process after hole enlargement. Background Technology

[0002] Underground mine reaming operations often face challenges such as heterogeneous rock formations and complex geological conditions. Traditional reaming drill bits primarily function to enlarge the borehole diameter, with their structural design emphasizing cutting efficiency during forward drilling. However, in practical use, especially during the drill bit retraction process after reaming, jamming frequently occurs due to irregular borehole walls, accumulation and blockage of rock cuttings generated during reaming, or encounters with fractured zones. This not only severely impacts operational efficiency and increases reaming time but can also damage the drill bit, drill body, and even drilling equipment, increasing the maintenance costs of mine drilling equipment. Therefore, developing a reaming drill bit that can effectively reduce or avoid jamming during the reaming retraction process is of significant practical importance. Summary of the Invention

[0003] To address the problems in the prior art, this utility model provides a drill bit for preventing jamming and reaming. The technical solution is as follows: the drill bit body is divided into a drill head, a reaming section, and a connecting section. The top of the drill head is fixedly provided with a plurality of first grinding teeth. The outer wall of the reaming section is evenly spaced with a plurality of first chip guide grooves. A second grinding tooth is fixedly provided between the inlets of adjacent first chip guide grooves. A third grinding tooth is fixedly provided between the outlets of adjacent first chip guide grooves. The connecting section is threadedly connected to the drill bit through a connecting hole.

[0004] In a preferred embodiment, the bottom of the connecting hole is provided with a water inlet hole, the inlet and outlet of the first chip guide groove of the enlarged hole are provided with a second water outlet hole and a third water outlet hole, the top of the drill bit is provided with a first water outlet hole, and the water inlet hole is connected to the first water outlet hole, the second water outlet hole and the third water outlet hole through the flow channel inside the drill bit body.

[0005] In a preferred embodiment, the reaming section is a frustum structure, with a large diameter end near the drill bit and a small diameter end near the connecting part. The frustum structure of the reaming section is adapted to the reaming requirements, and the diameter gradually decreases from the drill bit to the connecting part.

[0006] In a preferred embodiment, the first chip guide groove is a groove-shaped sloping structure, with the side closer to the drill bit being the high point and the side closer to the connection being the low point, and its slope being 13°-17°.

[0007] In a preferred embodiment, the first grinding tooth, the second grinding tooth, and the third grinding tooth are cemented carbide teeth or diamond composite teeth.

[0008] In a more preferred embodiment, at least two second water outlet holes are arranged in a circumferential array around the axis of the enlarged hole portion.

[0009] In a preferred embodiment, the drill bit has second chip guide grooves on both sides.

[0010] The beneficial effects of this utility model are:

[0011] (1) The reaming section adopts a frustum structure with a large diameter on the drill head side and a small diameter on the connecting section side. When reaming, the hole diameter is gradually increased from the bottom of the hole to the opening. When retracting, the small diameter end goes first, which greatly reduces the contact area between the reaming section and the hole wall, avoids the problem of full circumferential wall friction when retracting traditional equal diameter drill bits, and significantly reduces the retraction resistance.

[0012] (2) The first chip guide groove is a groove-shaped slope of 13°-17° (higher on the drill head side and lower on the connecting part side). The rock cuttings generated by the hole enlargement can slide naturally along the slope towards the hole opening, avoiding the accumulation in the groove or at the bottom of the hole to form a jamming pad. At the same time, the second chip guide grooves on both sides of the drill head can help to discharge the rock cuttings cut by the drill head, forming a double chip guide, eliminating the hidden danger of the drill bit jamming caused by the accumulation of rock cuttings.

[0013] (3) The third grinding tooth set on the back of the hole enlargement section can grind and break the local jamming point (such as small pieces of hard rock or slag) during the drill bit retraction process, clear the obstacle and help the drill bit to exit smoothly;

[0014] (4) The combination of the chip guide groove and the grinding teeth works synergistically from the two aspects of unblocking chip removal and actively removing obstacles, which significantly improves the smoothness of the drill bit during the retraction process after reaming.

[0015] (5) Effectively solves the problem of drill bit jamming during retraction, significantly shortens the processing time caused by drill bit jamming, improves the overall efficiency of hole enlargement operation, reduces equipment waste and potential damage risks, and reduces the operation and maintenance costs of mining rock drilling equipment. Attached Figure Description

[0016] Figure 1 This is a front view of the present invention.

[0017] Figure 2 This is a top view of the present invention.

[0018] Figure 3 This is a schematic diagram of the overall structure of this utility model.

[0019] In the figure: 1. Drill bit body; 101. Drill head; 102. Reaming section; 103. Connecting section; 2. First grinding tooth; 3. First chip guide groove; 4. Second grinding tooth; 5. Third grinding tooth; 6. Connecting hole; 7. Water inlet hole; 8. First water outlet hole; 9. Second water outlet hole; 10. Third water outlet hole; 11. Second chip guide groove. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0021] Example

[0022] like Figure 1-2 The illustrated drill bit for anti-jamming and hole-reaming includes a drill body 1, which is divided into a drill head 101, a reaming section 102, and a connecting section 103. The top of the drill head 101 is fixedly provided with several first grinding teeth 2. Several first chip guide grooves 3 are evenly spaced on the outer wall of the reaming section 102. Second grinding teeth 4 are fixedly provided between the inlets of adjacent first chip guide grooves 3, and third grinding teeth 5 are fixedly provided between the outlets of adjacent first chip guide grooves 3. The connecting section 103 is threadedly connected to the drill bit through a connecting hole 6. The first grinding teeth 2 of the drill head 101 are responsible for the initial cutting at the bottom of the hole. The second grinding teeth 4 at the inlets of adjacent first chip guide grooves are responsible for breaking the rock at the leading edge of the reaming. The third grinding teeth 5, located on the back side of the reaming section, can grind and break up local jamming points (such as small pieces of hard rock or slag) during the drill bit's retraction, clearing obstacles and helping the drill bit to retract smoothly.

[0023] Furthermore, a water inlet hole 7 is provided at the bottom of the connecting hole 6, and a second water outlet hole 9 and a third water outlet hole 10 are provided at the inlet and outlet of the first chip guide groove 3 of the enlarged hole section 102. A first water outlet hole 8 is provided at the top of the drill head 101. The water inlet hole 7 connects the first water outlet hole 8, the second water outlet hole 9, and the third water outlet hole 10 through the flow channel inside the drill bit body 1. This allows for targeted cooling of the grinding teeth in various areas, preventing accelerated tooth wear due to localized overheating, and also preventing rock cuttings from agglomerating and clogging the chip guide groove at high temperatures.

[0024] Furthermore, the reaming section 102 has a frustum structure, with a large-diameter end near the drill head 101 and a small-diameter end near the connecting section 103. The frustum structure of the reaming section 102 adapts to the reaming requirements, with the diameter gradually decreasing from the drill head to the connecting section. This significantly reduces the contact area between the reaming section and the hole wall, resulting in a significant reduction in retraction resistance.

[0025] Furthermore, the first chip guide groove 3 has a groove-shaped sloping structure, with a high point near the drill bit 101 and a low point near the connecting part 103, with a slope of 15°. The sloping structure of the first chip guide groove 3 does not weaken the strength of the reaming section while also ensuring chip removal, resulting in strong structural stability.

[0026] Furthermore, the first grinding tooth 2, the second grinding tooth 4, and the third grinding tooth 5 are cemented carbide teeth. Cemented carbide teeth have a much higher hardness than traditional carbon steel teeth, and can withstand the impact and wear of heterogeneous rock strata in mines (such as gravel-containing and fractured rocks). They are not prone to chipping or dulling, reducing the problem of irregular hole enlargement caused by tooth damage, and indirectly reducing the probability of drill bit jamming.

[0027] Furthermore, four second water outlet holes 9 are arranged in a circumferential array around the axis of the enlarged borehole 102. The fluid ejected from the multi-directional water outlet holes can wash away rock cuttings along the slope of the cuttings guide groove, accelerating their discharge towards the borehole opening; in particular, the four second water outlet holes arranged in a circumferential array can form a ring-shaped washing area, ensuring that rock cuttings around the entire circumference of the enlarged borehole can be effectively cleaned, further reducing the risk of the drill bit getting stuck.

[0028] Furthermore, the drill bit 101 has second chip guide grooves 11 on both sides.

[0029] The operation of the above-mentioned device is as follows: The rock drill is started and slowly advanced. The first grinding tooth 2 at the top of the drill bit 101 contacts the rock at the bottom of the hole, breaking the rock mass under the action of rotational cutting. Simultaneously, the second cuttings guide grooves 11 on both sides of the drill bit begin to discharge the initial rock cuttings. The water jet from the first water outlet 8 cools the first grinding tooth and moistens the rock cuttings, preventing dust from flying. As the drill bit advances, the reaming section 102 gradually enters the original hole. The second grinding tooth 4 between the inlets of the adjacent first cuttings guide grooves 3 contacts the original hole wall first, gradually enlarging the hole diameter to the target size under the guidance of the frustum structure. The water jet from the second water outlet 9 washes away the rock cuttings along the slope of the first cuttings guide groove, and the rock cuttings slide towards the hole opening under the action of gravity and water flow. When the reaming depth reaches the design requirements, the drill bit retraction process is initiated by slowly pulling the rock drill handle in the opposite direction. At this time, the frustum structure of the reaming section 102 retracts with the smaller diameter end leading. Compared to traditional equal-diameter drill bits, the frustum structure reduces the contact area between the drill bit and the borehole wall, significantly lowering the retraction resistance. The sloping structure of the first chip guide groove 3 continuously guides residual rock chips to be discharged towards the borehole opening, preventing rock chips from accumulating behind the drill bit and forming a jamming pad. If slight jamming occurs during the retraction process, there is no need to stop the machine for disassembly. A combination of forward rotation, small-amplitude advance, and increased water supply can be used to break up the jammed rock chips with the third grinding tooth 5 and flush the channel with water, thus restoring smooth retraction. This avoids the cumbersome operation of disassembling the drill bit after it jams, as is common with traditional drill bits.

Claims

1. A drill bit for preventing jamming during drill bit retraction, comprising a drill bit body (1), wherein the drill bit body (1) is divided into a drill head (101), a reaming section (102), and a connecting section (103), characterized in that, The top of the drill bit (101) is fixedly provided with a number of first grinding teeth (2), and a number of first chip guide grooves (3) are evenly spaced on the outer wall of the reaming part (102). A second grinding tooth (4) is fixedly provided between the inlets of adjacent first chip guide grooves (3), and a third grinding tooth (5) is fixedly provided between the outlets of adjacent first chip guide grooves (3). The connecting part (103) is threadedly connected to the drill bit through the connecting hole (6).

2. The anti-jamming drill bit for retracting holes according to claim 1, characterized in that, The bottom of the connecting hole (6) is provided with a water inlet hole (7), the inlet and outlet of the first chip guide groove (3) of the enlarged hole part (102) are provided with a second water outlet hole (9) and a third water outlet hole (10), the top of the drill head (101) is provided with a first water outlet hole (8), and the water inlet hole (7) is connected to the first water outlet hole (8), the second water outlet hole (9) and the third water outlet hole (10) through the flow channel inside the drill body (1).

3. The anti-jamming drill bit for retracting holes according to claim 1, characterized in that, The enlarged hole section (102) has a frustum structure, with a large diameter end on the side near the drill head (101) and a small diameter end on the side near the connecting part (103). The frustum structure of the enlarged hole section (102) is adapted to the enlarged hole requirements, and the diameter gradually decreases from the drill head to the connecting part.

4. The anti-jamming drill bit for retracting holes according to claim 1, characterized in that, The first chip guide groove (3) is a groove-shaped slope structure, with the side near the drill bit (101) being the high point and the side near the connecting part (103) being the low point, and its slope is 13°-17°.

5. A drill bit for preventing jamming during retraction and hole enlarging according to claim 1, characterized in that, The first grinding tooth (2), the second grinding tooth (4) and the third grinding tooth (5) are cemented carbide teeth or diamond composite teeth.

6. The anti-jamming drill bit for retracting holes according to claim 2, characterized in that, The second water outlet (9) is arranged in a circumferential array around the axis of the enlarged hole (102), with at least two of them.

7. The anti-jamming drill bit for retracting holes according to claim 1, characterized in that, The drill bit (101) has a second chip guide groove (11) on both sides.

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