High-low voltage alternating pulse auxiliary rock breaking PDC drill bit

Abstract

The utility model discloses a high-low pressure alternating pulse auxiliary rock breaking PDC drill bit, which relates to the technical field of petroleum drilling, and comprises a drill bit main body, the drill bit main body is provided with an inner ring nozzle and an outer ring nozzle, the diameter of the inner ring nozzle is different from that of the outer ring nozzle, the drill bit further comprises a guide plate sleeved in an inner cavity of the drill bit main body, and the periphery of the guide plate is provided with a guide hole; the top of the impeller is connected with the flow guide plate; the fixed baffle is arranged in an inner cavity of the drill bit body in a sleeving mode and comprises arc-shaped baffles arranged in the middle of the impeller in a sleeving mode, lower baffles are arranged at the bottoms of the vertical overflowing holes between every two adjacent arc-shaped baffles, and horizontal overflowing holes are formed between every two adjacent lower baffles; the movable disc valve is arranged at the bottom of the impeller in a sleeving mode, overflowing holes are formed in the periphery of the movable disc valve, and when fluid washes the impeller through the flow guide holes, the impeller drives the movable disc valve to rotate, so that alternate jetting of the inner ring nozzle and the outer ring nozzle is achieved, the rock breaking efficiency of the PDC drill bit is improved, the well bottom state can be effectively improved, and the well drilling cost is reduced.

Description

Technical Field

[0001] This utility model relates to the field of oil drilling technology, and more specifically, to a high-low pressure alternating pulse assisted rock breaking PDC drill bit. Background Technology

[0002] As drilling depths in oil exploration gradually increase, drilling difficulty also increases. Currently, deep and ultrasonic drilling often uses PDC drill bits. However, during drilling, high temperature, high hardness, and highly abrasive formations lead to increased wear rates of cutting teeth. PDC drill bits, when used in conjunction with downhole percussion tools, further accelerate the damage and wear of the cutting teeth. At the same time, the high temperature at the bottom of the well causes high tensile stress in the diamond layer on the cutting teeth, which can easily lead to tooth breakage and delamination, severely shortening the life of PDC drill bits.

[0003] To improve the efficiency of deep and ultra-deep drilling, one approach is to improve the rock-breaking performance and wear resistance of the drill bit by mixing tooth distribution. Another approach is to add hydraulic pulse tools, such as drill bit nozzles, to the drill bit to achieve high-pressure pulse jet assistance in rock breaking. However, due to the limitation of the drill bit nozzle diameter, the pulse jet energy it can generate is relatively small, which cannot achieve effective high-pressure pulse jet injection and results in poor rock-breaking assistance.

[0004] In conclusion, how to improve the rock-breaking performance of PDC drill bits is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0005] In view of this, the purpose of this utility model is to provide a high-low pressure alternating pulse assisted rock breaking PDC drill bit, which realizes the alternating injection of inner and outer ring nozzles through the relative rotation of impeller and moving disc valve with fixed baffle, which not only improves the rock breaking efficiency of PDC drill bit, but also effectively improves the bottom hole condition and reduces drilling costs.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A high-low pressure alternating pulse assisted rock breaking PDC drill bit includes a drill bit body, wherein the drill bit body is provided with an inner ring nozzle and an outer ring nozzle, the diameter of the inner ring nozzle and the diameter of the outer ring nozzle being different to form a high-low pressure alternating pulse jet, and further includes:

[0008] A guide plate fitted inside the inner cavity of the drill bit body has guide holes on its outer periphery;

[0009] The impeller is connected to the guide plate at the top and has at least one flow-diverting hole in the middle.

[0010] A fixed baffle fitted inside the drill bit body includes an arc-shaped baffle fitted in the middle of the impeller, a lower baffle is provided at the bottom of the vertical flow hole between two adjacent arc-shaped baffles, and a horizontal flow hole is provided between two adjacent lower baffles.

[0011] The moving disc valve, which is fitted onto the bottom of the impeller, has at least one flow passage hole on its outer periphery. When fluid flows through the flow passage hole and washes against the impeller, the impeller drives the moving disc valve to rotate.

[0012] When the diversion orifice is completely blocked by the arc-shaped baffle, the fluid enters the annular flow channel through the horizontal flow orifice and the flow orifice, and the outer ring nozzle sprays the fluid.

[0013] When the flow passage is completely blocked by the lower baffle, the fluid enters the internal flow channel through the vertical flow passage and the inner cavity of the impeller, and the inner ring nozzle sprays the fluid.

[0014] Preferably, the arc-shaped baffles are all the same size and are evenly distributed along the circumference of the fixed baffle, so that the size of the vertical flow hole between any two adjacent arc-shaped baffles is the same.

[0015] The lower baffles are all the same size and are evenly distributed along the circumference of the fixed baffle, so that the size of the horizontal flow holes between any two adjacent lower baffles is the same.

[0016] Preferably, when the diversion orifice is partially blocked by the arc-shaped baffle, the flow passage is partially blocked by the lower baffle to avoid damage to the components caused by a sudden increase in pump pressure.

[0017] Preferably, the impeller is provided with two flow-dividing holes evenly along the circumferential direction, and the moving disc valve is provided with two flow-through holes evenly along the circumferential direction, with the two flow-dividing holes and the two flow-through holes being orthogonally arranged.

[0018] Preferably, the inner cavity of the drill bit body is provided with a flow divider at one end relatively close to the cutting part. The flow divider is used to separate the internal flow channel and the annular flow channel. The impeller is rotatably sleeved in the flow divider through a bearing, and the outer diameter of the flow divider is smaller than the minimum distance from the flow hole to the axis of the moving disc valve.

[0019] Preferably, the inner circumference of the distributor is provided with a retaining circlip groove for installing a retaining circlip, the retaining circlip being used to limit the axial movement of the bearing.

[0020] Preferably, the inner circumference of the distributor is provided with a sealing groove for installing a sealing ring, and the sealing ring is disposed between the outer circumferential surface of the bearing and the sealing groove.

[0021] Preferably, the drill bit body and the diverter are an integral structure.

[0022] Preferably, the drill bit body includes a cutting part and a connecting part, the inner cavity of the cutting part is provided with an internal thread, and the connecting part is provided with an external thread that mates with the internal thread.

[0023] Preferably, the diameter of the inner ring nozzle is smaller than the diameter of the outer ring nozzle, so that the high-pressure jet from the inner ring nozzle and the low-pressure jet from the outer ring nozzle form a high-low pressure alternating pulse.

[0024] The high and low pressure alternating pulse assisted rock breaking PDC drill bit provided by this utility model allows the fluid to directly flush the impeller after passing through the guide hole of the guide plate, driving the moving disc valve to rotate around the shaft. When the flow distribution hole of the impeller is completely blocked by the arc-shaped baffle, the fluid enters the annular flow channel and is sprayed by the outer ring nozzle. When the flow passage hole of the moving disc valve is completely blocked by the lower baffle, the fluid enters the inner flow channel and is sprayed by the inner ring nozzle.

[0025] Therefore, the high and low pressure alternating pulse assisted rock breaking PDC drill bit mentioned above realizes the alternating spraying of the inner and outer ring nozzles through the relative rotation of the impeller and the moving disc valve with the fixed baffle. On the one hand, it can change the stress state of the rock surface through the high and low pressure alternating pulse jet, thereby assisting the cutting teeth of the PDC drill bit to break the rock and improving the rock breaking efficiency of the PDC drill bit.

[0026] On the other hand, high and low pressure alternating pulse jets can effectively improve the bottom hole condition, reduce the pressure holding effect, and facilitate rock clearing and carrying, thereby increasing the drilling speed of deep and ultra-deep wells and reducing drilling costs. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of a specific embodiment of the high-low pressure alternating pulse assisted rock-breaking PDC drill bit provided by this utility model;

[0029] Figure 2 for Figure 1 A magnified view of a portion of the image;

[0030] Figure 3 This is a schematic diagram of the guide vane structure;

[0031] Figure 4 This is a schematic diagram of the impeller structure;

[0032] Figure 5 This is a structural diagram of the fixed baffle;

[0033] Figure 6 This is a schematic diagram of the moving disc valve.

[0034] Figure 7 This is a schematic diagram of the nozzle distribution for a PDC drill bit.

[0035] Figures 1-7 middle:

[0036] 10-Drill bit body; 11-Cutting teeth; 12-Inner ring nozzle; 13-Outer ring nozzle; 14-Flow divider; a-Internal flow channel; b-Annular flow channel; 1-Guide plate; 101-Flow guide hole; 2-Impeller; 201-Blade; 202-Flow divider hole; 3-Fixed baffle; 301-Arc-shaped baffle; 302-Lower baffle; 303-Vertical flow hole; 304-Horizontal flow hole; 4-Moving disc valve; 401-Flow hole; 5-Bearing; 6-Sealing ring; 7-Limit snap ring. Detailed Implementation

[0037] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0038] The core of this utility model is to provide a high-low pressure alternating pulse assisted rock breaking PDC drill bit. Through the relative rotation of the impeller and the moving disc valve with the fixed baffle, the inner and outer ring nozzles are alternately sprayed, which not only improves the rock breaking efficiency of the PDC drill bit, but also effectively improves the bottom hole condition and reduces drilling costs.

[0039] The high-low pressure alternating pulse assisted rock breaking PDC drill bit provided by this utility model includes a drill bit body 10, which is provided with an inner ring nozzle 12 and an outer ring nozzle 13. The diameters of the inner ring nozzle 12 and the outer ring nozzle 13 are different to form a high-low pressure alternating pulse jet. It also includes:

[0040] The guide plate 1, which is fitted into the inner cavity of the drill bit body 10, has a guide hole 101 on its outer periphery;

[0041] Impeller 2, with its top connected to guide plate 1, and at least one flow divider hole 202 in the middle;

[0042] The fixed baffle 3 fitted inside the drill bit body 10 includes an arc-shaped baffle 301 fitted in the middle of the impeller 2, a lower baffle 302 at the bottom of the vertical flow hole 303 between two adjacent arc-shaped baffles 301, and a horizontal flow hole 304 between two adjacent lower baffles 302.

[0043] The moving disc valve 4, which is fitted at the bottom of the impeller 2, has at least one flow passage hole 401 on its outer periphery. When the fluid flows through the guide hole 101 and washes the impeller 2, the impeller 2 drives the moving disc valve 4 to rotate.

[0044] When the diversion orifice 202 is completely blocked by the arc-shaped baffle 301, the fluid enters the annular flow channel b through the horizontal flow passage 304 and the flow passage 401, and the outer ring nozzle 13 sprays the fluid.

[0045] When the flow passage 401 is completely blocked by the lower baffle 302, the fluid enters the internal flow channel a through the vertical flow passage 303 and the inner cavity of the impeller 2, and the inner ring nozzle 12 sprays the fluid.

[0046] Please refer to Figure 1 The drill bit body 10 includes a cutting section and a connecting section for connecting with the drill bit. The cutting section is provided with cutting teeth 11, an inner ring nozzle 12 and an outer ring nozzle 13. The number, type, size and distribution of the cutting teeth 11 are determined according to actual production needs, such as the rock breaking performance and design life of the PDC drill bit.

[0047] The inner ring nozzle 12 is located in the center region of the flow channel of the drill body 10 and is connected to the inner flow channel a of the drill body 10. The outer ring nozzle 13 is located in the outer region of the flow channel of the drill body 10 and is connected to the annular flow channel b of the drill body 10. It should be noted that in order to achieve the alternating spraying of the inner and outer ring nozzles, a flow divider 14 is provided at the end of the drill body 10 that is relatively close to the cutting part. The flow divider 14 is used to separate the inner flow channel a and the annular flow channel b.

[0048] The inner and outer ring nozzles can be specifically configured as pulse nozzles, self-oscillating cavitation nozzles, and extended nozzles, etc. The specific structure, quantity, and distribution of the two need to be set according to the working environment of the PDC drill bit in actual production, such as rock clearing and rock carrying targets, while the diameter and other dimensions of the two need to be reasonably set according to the design displacement of the PDC drill bit.

[0049] The inner ring nozzle 12 has a different diameter than the outer ring nozzle 13, resulting in different jet pressures between the inner and outer ring nozzles. Therefore, alternating high and low pressure pulse jets can be formed by the alternating jets of the inner and outer ring nozzles 13. Considering that the inner ring nozzle 12 is usually used to generate high pressure pulses, the inner ring nozzle 12 needs to be made of a high pressure resistant and erosion resistant material, and the diameter of the inner ring nozzle 12 is smaller than the diameter of the outer ring nozzle 13, so that the high pressure jet of the inner ring nozzle 12 and the low pressure jet of the outer ring nozzle 13 can form a high and low pressure alternating pulse.

[0050] Of course, the inner ring nozzle 12 can also be set to have a larger diameter than the outer ring nozzle 13. In this case, the outer ring nozzle 13 is used to spray high-pressure jets and the inner ring nozzle 12 is used to spray low-pressure jets. The outer ring nozzle 13 needs to be made of a high-pressure resistant and erosion-resistant material.

[0051] The guide plate 1 is fitted into the inner cavity of the drill bit body 10 and is used to guide the fluid inside the drill bit body 10 so that the fluid directly scours the blades 201 of the impeller 2. The specific number, shape, size and distribution of the guide holes 101 on its outer periphery need to be determined according to the actual production needs, such as the structure, shape, size and distribution of the blades 201 of the impeller 2 and the design displacement of the PDC drill bit.

[0052] The guide plate 1 is usually installed in the inner cavity of the drill bit body 10 with a clearance fit. In order to facilitate the axial positioning of the guide plate 1, the inner cavity of the drill bit body 10 is preferably provided with a positioning step.

[0053] The top of the impeller 2 is rotatably connected to the guide plate 1, and the bottom is fitted with a moving disc valve 4. When the fluid directly washes the blades 201 of the impeller 2 to make them rotate, the impeller 2 drives the moving disc valve 4 to rotate synchronously. Through the rotation of the impeller 2 and the moving disc valve 4 relative to the fixed baffle 3, the conduction state of the flow divider hole 202 of the impeller 2 and the flow passage hole 401 of the moving disc valve 4 is periodically adjusted, thereby changing the opening state of the internal flow channel a and the annular flow channel b of the drill bit body 10, and finally realizing the alternating spraying of the inner and outer ring nozzles.

[0054] During operation, the fluid flows directly over the impeller 2 after passing through the guide hole 101 of the guide plate 1, causing the moving disc valve 4 to rotate around the shaft. When the flow distribution hole 202 of the impeller 2 is completely blocked by the arc-shaped baffle 301, the fluid enters the annular flow channel b and the outer ring nozzle 13 sprays the fluid.

[0055] When the flow passage 401 of the moving disc valve 4 is completely blocked by the lower baffle 302, the fluid enters the internal flow channel a and the inner ring nozzle 12 sprays the fluid.

[0056] In this embodiment, the relative rotation of the impeller 2 and the moving disc valve 4 with the fixed baffle 3 enables the alternating spraying of the inner and outer ring nozzles. On the one hand, the high and low pressure alternating pulse jet can change the stress state of the rock surface, thereby assisting the cutting teeth 11 of the PDC drill bit in breaking the rock and improving the rock breaking efficiency of the PDC drill bit.

[0057] On the other hand, high and low pressure alternating pulse jets can effectively improve the bottom hole condition, reduce the pressure holding effect, and facilitate rock clearing and rock carrying, thereby increasing the drilling speed of deep and ultra-deep layers and reducing drilling costs.

[0058] Preferably, when the flow divider 202 of the impeller 2 is partially blocked by the arc-shaped baffle 301, the flow passage 401 of the moving disc valve 4 is partially blocked by the lower baffle 302. Therefore, the internal flow channel a and the annular flow channel b are simultaneously open to avoid damage to components caused by a sudden increase in pump pressure.

[0059] During operation, the fluid flows through the guide hole 101 of the guide plate 1 and directly washes the impeller 2 to rotate. The impeller 2 drives the moving disc valve 4 to rotate synchronously. When the flow hole 401 of the moving disc valve 4 rotates to coincide with the horizontal flow hole 304 of the fixed baffle 3, the annular flow channel b opens and the outer ring nozzle 13 sprays fluid. At this time, the flow splitting hole 202 of the impeller 2 coincides with the arc-shaped baffle 301 of the fixed baffle 3, and the internal flow channel a closes.

[0060] Impeller 2 drives the moving disc valve 4 to continue rotating. The flow passage 401 of the moving disc valve 4 is not completely closed, and the flow distribution hole 202 of the impeller 2 is initially opened. The internal flow channel a and the annular flow channel b are simultaneously open. The inner and outer ring nozzles spray fluid at the same time to prevent the pump pressure from increasing sharply and causing damage to the components.

[0061] When the impeller 2 continues to rotate until the flow passage 401 of the moving disc valve 4 is completely closed by the lower baffle 302, the annular flow channel b opens. At this time, the flow distribution hole 202 of the impeller 2 is no longer blocked by the arc-shaped baffle 301, the flow distribution hole 202 is fully open, the internal flow channel a is opened, and the inner ring nozzle 12 sprays fluid.

[0062] Based on the above embodiments, in order to facilitate the periodic changes of the high and low pressure alternating pulse jet, the structure of the fixed baffle 3 is defined. Please refer to [reference needed]. Figure 5 All the arc-shaped baffles 301 have the same size and are evenly distributed along the circumference of the fixed baffle 3 so that the vertical flow holes 303 between any two adjacent arc-shaped baffles 301 have the same size.

[0063] The dimensions of the lower baffles 302 are all the same, and the lower baffles 302 are evenly distributed along the circumference of the fixed baffle 3 so that the dimensions of the horizontal flow holes 304 between any two adjacent lower baffles 302 are the same.

[0064] In this embodiment, by setting the arc-shaped baffle 301 and the vertical flow passage 303 evenly distributed along the circumference of the fixed baffle 3, the flow diversion hole 202 of the impeller 2 can be periodically blocked or opened, so as to realize the periodic opening and closing of the internal flow channel a, thereby realizing the periodic adjustment of the flow rate of the inner ring nozzle 12.

[0065] Meanwhile, by setting the lower baffle 302 and the horizontal flow passage 304 evenly along the circumference of the fixed baffle 3, the flow passage 401 of the moving disc valve 4 can be periodically blocked or opened, so as to realize the periodic opening and closing of the annular flow channel b, thereby realizing the periodic adjustment of the flow rate of the outer ring nozzle 13.

[0066] The number of arc-shaped baffles 301 on the fixed baffle 3 is determined by the number of flow divider holes 202 on the impeller 2, and the two are the same; the number of upper and lower baffles 302 on the fixed baffle 3 is determined by the number of flow passage holes 401 on the moving disc valve 4, and the two are the same.

[0067] In a specific embodiment, considering that the design flow rate of the PDC drill bit should not be too small, the impeller 2 is provided with two diversion holes 202 evenly along the circumferential direction, and the moving disc valve 4 is provided with two flow passage holes 401 evenly along the circumferential direction, and the two diversion holes 202 and the two flow passage holes 401 are orthogonally arranged.

[0068] Based on the above embodiments, the rotational connection method of the impeller 2 is defined. A flow divider 14 is provided at the end of the inner cavity of the drill body 10 that is relatively close to the cutting part. The flow divider 14 is used to separate the internal flow channel a and the annular flow channel b. In order to facilitate the assembly of the drill body 10, it is preferable to set the drill body 10 and the flow divider 14 as an integral structure. Of course, the two can also be connected by means of threaded connection, pin connection, etc.

[0069] The impeller 2 is rotatably mounted inside the distributor 14 via the bearing 5, and the outer diameter of the distributor 14 is smaller than the minimum distance from the flow hole 401 to the axis of the moving disc valve 4.

[0070] Please refer to Figure 2 The inner circumference of the distributor 14 is provided with a retaining circlip groove for installing the retaining circlip 7, which is used to limit the axial movement of the bearing 5.

[0071] In order to effectively seal and separate the internal flow channel a and the annular flow channel b, the inner circumference of the distributor 14 is preferably provided with a sealing groove for installing the sealing ring 6, and the sealing ring 6 is located between the outer circumferential surface of the bearing 5 and the sealing groove.

[0072] Based on the above embodiments, in order to facilitate the installation of structures such as the impeller 2 inside the drill bit body 10, the drill bit body 10 includes a cutting part and a connecting part. The inner cavity of the cutting part is provided with an internal thread, and the outer part of the connecting part is provided with an external thread that mates with the internal thread. The threaded connection structure is simple, easy to process, and has good sealing performance.

[0073] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0074] The high- and low-pressure alternating pulse assisted rock-breaking PDC drill bit provided by this utility model has been described in detail above. Specific examples have been used to illustrate the principle and implementation of this utility model. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core idea of ​​this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made to this utility model without departing from the principle of this utility model, and these improvements and modifications also fall within the protection scope of the claims of this utility model.

Claims

1. A high-low pressure alternating pulse assisted rock breaking PDC drill bit, comprising a drill bit body (10), wherein the drill bit body (10) is provided with an inner ring nozzle (12) and an outer ring nozzle (13), characterized in that, The inner ring nozzle (12) has a different diameter than the outer ring nozzle (13) to form a high-low pressure alternating pulse jet, and also includes: A guide plate (1) fitted inside the drill bit body (10) has a guide hole (101) on its outer periphery. The impeller (2) is connected to the guide plate (1) at the top and has at least one diversion hole (202) in the middle. The fixed baffle (3) sleeved in the inner cavity of the drill bit body (10) includes an arc-shaped baffle (301) sleeved in the middle of the impeller (2), a lower baffle (302) is provided at the bottom of the vertical flow hole (303) between two adjacent arc-shaped baffles (301), and a horizontal flow hole (304) is provided between two adjacent lower baffles (302). The moving disc valve (4) fitted at the bottom of the impeller (2) has at least one flow passage hole (401) on its outer periphery. When the fluid flows through the guide hole (101) and washes the impeller (2), the impeller (2) drives the moving disc valve (4) to rotate. When the diversion orifice (202) is completely blocked by the arc-shaped baffle (301), the fluid enters the annular flow channel (b) through the horizontal flow passage (304) and the flow passage (401), and the outer ring nozzle (13) sprays the fluid. When the flow passage (401) is completely blocked by the lower baffle (302), the fluid enters the internal flow channel (a) through the vertical flow passage (303) and the inner cavity of the impeller (2), and the inner ring nozzle (12) sprays the fluid.

2. The high-low pressure alternating pulse assisted rock-breaking PDC drill bit according to claim 1, characterized in that, The arc-shaped baffles (301) are all the same size, and the arc-shaped baffles (301) are evenly distributed along the circumferential direction of the fixed baffle (3) so that the vertical flow holes (303) between any two adjacent arc-shaped baffles (301) are all the same size; The dimensions of the lower baffles (302) are all the same, and the lower baffles (302) are evenly distributed along the circumferential direction of the fixed baffle (3) so that the dimensions of the horizontal flow holes (304) between any two adjacent lower baffles (302) are all the same.

3. The high-low pressure alternating pulse assisted rock-breaking PDC drill bit according to claim 2, characterized in that, When the diversion hole (202) is partially blocked by the arc-shaped baffle (301), the flow passage (401) is partially blocked by the lower baffle (302) to avoid damage to the components caused by a sudden increase in pump pressure.

4. The high-low pressure alternating pulse assisted rock-breaking PDC drill bit according to claim 3, characterized in that, The impeller (2) is provided with two flow divider holes (202) evenly along the circumferential direction, and the moving disc valve (4) is provided with two flow passage holes (401) evenly along the circumferential direction, and the two flow divider holes (202) and the two flow passage holes (401) are orthogonally arranged.

5. The high-low pressure alternating pulse assisted rock-breaking PDC drill bit according to any one of claims 1-4, characterized in that, The inner cavity of the drill bit body (10) is provided with a flow divider (14) at one end relative to the cutting part. The flow divider (14) is used to separate the internal flow channel (a) and the annular flow channel (b). The impeller (2) is rotatably sleeved in the flow divider (14) through the bearing (5). The outer diameter of the flow divider (14) is smaller than the minimum distance from the flow hole (401) to the axis of the moving disc valve (4).

6. The high-low pressure alternating pulse assisted rock-breaking PDC drill bit according to claim 5, characterized in that, The inner circumference of the distributor (14) is provided with a retaining groove for installing a retaining circlip (7), which is used to limit the axial movement of the bearing (5).

7. The high-low pressure alternating pulse assisted rock-breaking PDC drill bit according to claim 5, characterized in that, The inner circumference of the distributor (14) is provided with a sealing groove for installing a sealing ring (6), and the sealing ring (6) is located between the outer circumferential surface of the bearing (5) and the sealing groove.

8. The high-low pressure alternating pulse assisted rock-breaking PDC drill bit according to claim 5, characterized in that, The drill bit body (10) and the diverter (14) are an integral structure.

9. The high-low pressure alternating pulse assisted rock-breaking PDC drill bit according to any one of claims 1-4, characterized in that, The drill bit body (10) includes a cutting part and a connecting part. The inner cavity of the cutting part is provided with an internal thread, and the connecting part is provided with an external thread that mates with the internal thread.

10. The high-low pressure alternating pulse assisted rock-breaking PDC drill bit according to any one of claims 1-4, characterized in that, The diameter of the inner ring nozzle (12) is smaller than the diameter of the outer ring nozzle (13) so that the high-pressure jet of the inner ring nozzle (12) and the low-pressure jet of the outer ring nozzle (13) form a high-low pressure alternating pulse.

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