Rotatable blade PDC (Polycrystalline Diamond Compact) drill bit with upper and lower blades provided with two sets of cutting structures

Abstract

The invention belongs to the field of PDC drill bits, and particularly relates to a rotatable blade PDC drill bit with two sets of cutting structures on the upper portion and the lower portion of each blade, the rotatable blade PDC drill bit comprises a drill bit body and a butt-joint connector, the drill bit body is composed of a center cylinder and a drill crown, the drill crown is located at the top of the center cylinder, and the multiple blades are fixedly connected to the outer side of the drill bit body; a plurality of blades are arranged on the center cylinder, chip grooves are formed among the blades, the center cylinder is composed of a plurality of rotary drill bushings capable of rotating, the rotary drill bushings are mutually stacked from top to bottom, and a plurality of first PDC cutting teeth and second PDC cutting teeth are fixedly connected to the two sides of each blade respectively. Meanwhile, two sets of different cutting structures are matched, so that the drill bit can be suitable for efficient cutting and drilling work in different soil layer environments, the working efficiency is improved, meanwhile, the appropriate cutting teeth correspond to appropriate soil layers, damage to the cutting teeth can be reduced, and the service life of the drill bit can be prolonged.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of PDC drill bits, in particular to a rotatable-blade PDC drill bit with two sets of cutting structures on the upper and lower blades. BACKGROUND

[0002] PDC drill bit, full name is polycrystalline diamond compact drill bit. It is a kind of high-efficiency drilling tool for breaking rock by shearing. Its core component is PDC cutting tooth, which is composed of artificial synthetic polycrystalline reinforced layer and hard alloy substrate under high temperature and high pressure.

[0003] The working principle of PDC drill bit is to remove rock layer by shearing. Under the action of drilling pressure, PDC cutting tooth is eaten into the stratum, and under the action of torque, with the rotation of the drill bit, the sharp diamond layer is like a cutter to "cut" or "scrape" the rock at the bottom of the well, the drilling fluid is sprayed at high speed through the nozzle of the drill bit, which cools the cutting tooth and carries away the generated rock cuttings, keeping the bottom clean.

[0004] The traditional PDC drill bit often only uses fixed blades and cutting teeth, and in the drilling process, different strata and lithology are generally experienced, and the forces borne by the drill bit are greatly different during the cutting and drilling process of soft and hard rock layers. The traditional PDC drill bit also has different types, which are suitable for different strata, but if the drill bit is taken out and replaced every time different strata are encountered, a lot of working time will be wasted, which will greatly affect the working efficiency, and if the same drill bit is used for different strata, the drill bit will be damaged, and the working efficiency will also be greatly reduced.

[0005] Therefore, the present application provides a rotatable-blade PDC drill bit with two sets of cutting structures on the upper and lower blades. SUMMARY

[0006] In order to make up for the shortcomings of the prior art and solve at least one technical problem proposed in the background art.

[0007] The technical scheme adopted by the present application to solve its technical problems is: the rotatable-blade PDC drill bit with two sets of cutting structures on the upper and lower blades, comprising a drill bit body and a counter plug connector, the drill bit body is composed of a center column and a drill crown, the drill crown is located at the top of the center column, the outer side of the drill bit body is fixedly connected with a plurality of blades, the plurality of blades form a chip removal groove therebetween, the center column is composed of a plurality of rotatable rotary drill sleeves, the plurality of rotary drill sleeves are stacked from top to bottom, and the two sides of the blade are respectively fixedly connected with a plurality of PDC cutting teeth one and PDC cutting teeth two. Through the arrangement, not only the efficient rock cutting drilling function is realized, but also the drill bit can be suitable for efficiently cutting drilling work in different stratum environments, the working efficiency is improved, the suitable cutting teeth correspond to the suitable stratum, the damage to the cutting teeth can be reduced, the service life of the drill bit is improved, the overall switching mode is simple and convenient, the drill bit does not need to be taken out to the ground, and the complicated hydraulic control is not needed, and the switching can be completed by only changing the driving direction.

[0008] Two symmetrical locking grooves are arranged on the bottom of the plug-in connector, horizontal locking holes are arranged on the inner walls of the locking grooves, two horizontal cutting grooves are arranged on the outer side of the plug-in connector, and the plug-in connector is connected with the driving equipment through the locking grooves during work, so that the traditional threaded connection structure is replaced, the power can be smoothly transmitted during forward and reverse transmission, the locking buckle is used for locking the driving equipment, and the horizontal cutting groove is used for improving the transmission surface of the two.

[0009] A metal core is fixed to the top of the plug-in connector, a plug groove matched with the metal core is arranged at the inner center position of the center column, and a plurality of rotating drill sleeves are slidably connected with the metal core, the metal core is fixed to the drill crown during work, and the rotating drill sleeves are slidably connected to the outside, so that the rotating drill sleeves can rotate under the friction and change the shape.

[0010] A plurality of connecting arms are fixed to the inner ring of the rotating drill sleeve, arc-shaped clamping plates are fixed to the ends of the connecting arms, a plurality of clamping grooves matched with the connecting arms and the clamping plates are arranged on the outer surface of the metal core, the connecting arms and the clamping plates are inserted into the clamping grooves during work, the area of the clamping plate is greater than that of the outer side of the clamping groove, the connection stability of the rotating drill sleeve is ensured, the length of each group of clamping grooves is different, each rotating drill sleeve can reach the predetermined position after rotating to the limit position, the predetermined chip groove shape is formed, and the normal working process of the drill bit is ensured.

[0011] The back rake angle of the PDC cutting tooth one is smaller than that of the PDC cutting tooth two, the plurality of PDC cutting tooth ones and the plurality of PDC cutting tooth twos are equidistantly arranged, the arrangement interval of the PDC cutting tooth two is smaller than that of the PDC cutting tooth one, the PDC cutting tooth one and the PDC cutting tooth two are designed in this way during work, the two are suitable for strata with soft and hard lithology respectively, so that the drill bit can continuously cut and drill in most underground environments, the working efficiency is ensured, the high-density arrangement of the PDC cutting tooth two can better crush the rock, and the low-density arrangement of the PDC cutting tooth one can quickly discharge the cuttings generated by the soft stratum.

[0012] The plurality of blades is divided into two groups, the top of one group of blades extends as crown wing one, and the top of the other group of blades extends as crown wing two, both of which are fixed on the drill crown, the length of crown wing one is longer than that of crown wing two, during operation, the number of crown wing one can be three, the three crown wing ones are arranged in a ring shape at equal intervals, and there is partial bending, so that more cutting angles can cut rock and soil, the length of crown wing two is shorter, and is distributed between adjacent crown wing ones, through the combination of different lengths, the stratum rock can be better cut.

[0013] The end of the crown wing one is fixed with bidirectional teeth, the bidirectional teeth are the combination of PDC cutting teeth one and PDC cutting teeth two, and the end of the crown wing two has a large slope cutting angle, during operation, the bidirectional teeth are adapted to the shape of the end of the crown wing one, and the cutting effect of rock is further improved, and the end of the crown wing two is made into a more sharp excavation inclined angle through the large slope cutting angle, and the cutting effect is improved.

[0014] The top of the drill crown is provided with a plurality of drainage nozzles, the bottom of the insertion slot is provided with a plurality of transmission valves in communication with the drainage nozzles, and the bottom of the insertion connector is provided with a butt joint valve penetrating to the top, during operation, in order to ensure that the soil can be discharged faster, the butt joint valve is communicated with the external liquid conveying equipment, liquid is injected into the bottom of the drill hole through the metal core, the transmission valve and the drainage nozzle, the liquidity of the rock debris is enhanced, and the discharge of the rock debris is assisted.

[0015] The edge of the rotating drill sleeve close to the PDC cutting teeth one is a detachable sharp corner block structure, and the outer side of the edge is covered with a protective layer, during operation, when counterclockwise rotation, the edge position of the rotating drill sleeve is subjected to increased stress, the damage caused by friction can be well reduced by arranging the sharp corner block and covering the edge with the protective layer, the sharp corner block can be replaced, and the sharp corner block can be connected with the rotating drill sleeve in a bolted manner.

[0016] The outer side of the PDC cutting teeth one is fixed with a polishing block, the end of the polishing block is in a sharp corner shape and faces in the opposite direction of the PDC cutting teeth one, and the side, on which the PDC cutting teeth two is installed, of the blade is also provided with a plurality of additional teeth, the polishing block increases the friction degree when the back of the PDC cutting teeth one contacts the stratum, and in order to ensure the strength of the back of the PDC cutting teeth one, a diamond layer can also be covered on the back of the PDC cutting teeth one, the additional teeth are bolted on the inclined surface of the blade, the damage effect on rock is increased, and the additional teeth have an assisting effect when dealing with hard stratum.

[0017] The beneficial effects of the present application are as follows: 1. The PDC drill bit with two sets of cutting structures on the upper and lower blades, which is rotatable, is characterized in that: a plurality of rotatable rotary drill sleeves and two groups of PDC cutting teeth are arranged, so that the drill bit can efficiently cut and drill in different soil environments, the working efficiency is improved, the service life of the drill bit is prolonged, the appropriate cutting teeth are matched with the appropriate soil, the damage to the cutting teeth is reduced, the overall switching mode is simple and convenient, the drill bit does not need to be lifted to the ground, and the complicated hydraulic control is not needed, and the switching can be completed by changing the driving direction.

[0018] 2. The PDC drill bit with two sets of cutting structures on the upper and lower blades, which is rotatable, is characterized in that: the rear inclination angle, arrangement interval and size of PDC cutting teeth I and PDC cutting teeth II are different, so that the two are suitable for lithology of soft and hard strata respectively, so that the drill bit can be used in most stratum environments, the drill bit can continuously cut and drill, and the working efficiency is ensured; the high-density arrangement of PDC cutting teeth II can better crush the soil; and the low-density arrangement of PDC cutting teeth I can quickly cut soft rocks and discharge them outward. BRIEF DESCRIPTION OF DRAWINGS

[0019] The application will be further described below with reference to the drawings.

[0020] Figure 1 is the front view of the first perspective of the application; Figure 2 is the top view of the first perspective of the application; Figure 3 is the perspective view of the first perspective of the application; Figure 4 is the perspective view of the second perspective of the application; Figure 5 is the perspective view of the rotary drill sleeve and the drill crown of the application; Figure 6 is the perspective view of the crown wing I and the crown wing II of the application; Figure 7 is the perspective view of the sharp corner block and the additional tooth of the application; In the figure: 1, drill bit body; 2, plug-in connector; 3, drill crown; 4, blade; 5, PDC cutting tooth I; 6, PDC cutting tooth II; 7, center column; 8, chip removal groove; 9, liquid discharge nozzle; 10, butt joint valve; 11, rotary drill sleeve; 12, transmission valve; 13, insertion slot; 14, connecting arm; 15, metal core; 16, clamping groove; 17, polishing block; 18, sharp corner block; 19, locking groove; 41, crown wing I; 42, crown wing II; 51, bidirectional tooth; 23, additional tooth. DETAILED DESCRIPTION

[0021] In order to make the technical means, creative features, purposes and effects of the present application easy to understand, the present application is further described below in conjunction with specific embodiments.

[0022] As shown in Figures 1 to 7 The PDC drill bit with rotatable blades provided with two sets of cutting structures on the upper and lower blades according to the embodiment of the present application comprises a drill bit body 1 and a mating connector 2. The drill bit body 1 is composed of a central column 7 and a crown 3. The crown 3 is located at the top of the central column 7. A plurality of blades 4 are fixed to the outer side of the drill bit body 1. A plurality of blades 4 form a chip removal groove 8. The central column 7 is composed of a plurality of rotatable rotary drill sleeves 11. The plurality of rotary drill sleeves 11 are stacked from top to bottom. A plurality of PDC cutting teeth one 5 and PDC cutting teeth two 6 are respectively fixed to the two sides of the blade 4. The mating connector 2 is connected with the driving device to control the rotation of the mating connector 2 and the drill bit body 1. The crown 3 drills downward into the stratum. When encountering a slightly soft or moderately hard stratum, the drill bit body 1 rotates clockwise. At this time, the end face of the PDC cutting tooth one 5 contacts and cuts the stratum rock. The design of the plurality of PDC cutting tooth one 5 is aimed at the slightly soft and moderately hard stratum. The main difference lies in the volume, the back rake angle and the arrangement gap. In the rotation process, the blade 4 cuts the rock together with the PDC cutting tooth one 5. At the same time, the blade 4 is arc-shaped. The formed chip removal groove 8 is also arc-shaped. The drill bit body 1 and the blade 4 rotate clockwise downward. The cuttings move along the chip removal groove 8 to the ground. Thus, the cuttings are continuously extruded upward. The cuttings are discharged to the ground. The accumulation of cuttings at the bottom of the borehole is reduced, which affects the cutting work of the drill bit. When encountering a hard stratum, the driving device controls the reverse rotation of the mating connector 2 and the drill bit body 1. Since the central column 7 is composed of a plurality of rotary drill sleeves 11, when counterclockwise rotation is performed, the entire blade 4 will be rearranged under the action of friction. The rotation angle of each rotary drill sleeve 11 is limited. When clockwise rotation is performed, a neat arc-shaped posture will be formed. As shown in Figure 1 When counterclockwise rotation is performed, the final arc-shaped posture will be formed as shown in Figure 4In the shown mode, the other side of the blade wing 4 rubs and cuts the stratum rock, the PDC cutting tooth two 6 directly contacts the soil body, the design of the PDC cutting tooth two 6 is for hard stratum, and the improvement of the volume, the back rake angle and the arrangement gap is mainly designed, and because of the change of the blade wing 4, the arc of the chip removal groove 8 is matched with the counterclockwise rotating drill bit body 1 at this time, the bottom soil can still be transported upward, so that the drilling work of the drill bit can continue; through the arrangement, the efficient soil cutting and drilling function is realized, and the two different cutting structures are matched, so that the drill bit can be suitable for efficient cutting and drilling work in different stratum environments, the working efficiency is improved, the damage to the cutting tooth is reduced, and the service life of the drill bit is improved; meanwhile, the overall switching mode is simple and convenient, the drill bit does not need to be lifted to the ground, and complex hydraulic control is not needed, and the switching can be completed by changing the driving direction.

[0023] Two symmetrical locking grooves 19 are arranged at the bottom of the plug-in connector 2, horizontal locking holes are arranged on the inner wall of the locking grooves 19, and two horizontal cutting grooves are arranged on the outer side of the plug-in connector 2. When working, in order to ensure the smoothness of the transmission process, the plug-in connector 19 is connected with the transmission equipment through the locking groove, the traditional threaded connection structure is replaced, the power can be smoothly transmitted in the forward and reverse transmission process, the locking buckle is used for locking the transmission equipment, and the horizontal cutting groove is used for improving the transmission surface of the two.

[0024] The top of the plug-in connector 2 is fixedly connected with a metal core 15, a plug groove 13 matched with the metal core 15 is arranged at the inner center position of the center column 7, and a plurality of rotating drill sleeves 11 are slidably connected with the metal core 15. When working, the metal core 15 is fixedly connected with the drill crown 3, and the plurality of rotating drill sleeves 11 are slidably connected on the outer side, so that the rotating drill sleeve 11 can rotate under the action of friction and change the shape.

[0025] A plurality of connecting arms 14 are fixedly connected to the inner ring of the rotating drill sleeve 11, arc-shaped clamping plates are fixedly connected to the end portions of the connecting arms 14, and a plurality of clamping grooves 16 matched with the connecting arms 14 and the clamping plates are arranged on the outer surface of the metal core 15. When working, the connecting arms 14 and the clamping plates are inserted into the clamping grooves 16, the area of the clamping plate is greater than the outer side of the clamping groove 16, the connection stability of the rotating drill sleeve 11 is ensured, the length of each group of clamping grooves 16 is different, each rotating drill sleeve 11 can reach a predetermined position after rotating to the limit position, a predetermined chip removal groove 8 shape is formed, and the normal working process of the drill bit is ensured.

[0026] The back rake angle of the PDC cutting teeth one 5 is smaller than that of the PDC cutting teeth two 6, the plurality of PDC cutting teeth one 5 and the plurality of PDC cutting teeth two 6 are arranged at equal intervals, and the arrangement interval of the PDC cutting teeth two 6 is smaller than that of the PDC cutting teeth one 5; In operation, the PDC cutting teeth include a substrate and a diamond layer, the diamond layer is sintered from artificial polycrystalline diamond powder under high temperature and high pressure, has extremely high hardness, and is responsible for cutting rock, and the diamond layer is an excellent heat conductor. A large amount of friction heat generated in the cutting process can be quickly conducted away by the diamond layer and then taken away by the drilling fluid circulation; the substrate is usually a cemented carbide made of tungsten carbide powder and a metal binder through a powder metallurgy process, which constitutes the support body of the cutting tooth, and the diamond layer is extremely hard but brittle. The tough tungsten carbide substrate provides a solid "base" for the brittle diamond layer to withstand the bending stress, impact load and compression load from the rock, preventing the diamond layer from breaking; the back rake angle of the PDC cutting teeth one 5 is larger, and the back rake angle is the angle between the diamond layer surface of the PDC cutting tooth and the rock surface at the bottom of the well, which is generally negative; specifically, it is the angle between the vertical line of the working plane of the cutting tooth and the rock surface at the bottom of the well, and the size of the back rake angle directly determines the "aggressiveness" of the cutting tooth cutting into the rock and the "support" of the rock reaction force, when the back rake angle is smaller, it is negative, so the cutting tooth looks more "standing", the small back rake angle makes the cutting tooth very "sharp", like a standing knife. In soft strata, it only needs small drilling pressure to "bite" into the rock and perform efficient shearing action on the rock, like cutting butter with a knife; on the contrary, the larger the back rake angle, the more negative it is, the cutting tooth looks more "lying", so that the force acting on the cutting tooth (the reaction force from the rock) is more directly transmitted to the tooth column and the back of the drill bit body 1 along the axial direction, so that the cutting tooth is not easy to damage, sacrificing part of the aggressiveness, and obtaining high durability and impact resistance; By designing the PDC cutting teeth one 5 and the PDC cutting teeth two 6 in this way, they are suitable for soft and hard strata respectively, so they can be suitable for most strata environments in most areas, so that the drill bit can continue to cut and drill, ensuring work efficiency; At the same time, the high-density arrangement of the PDC cutting teeth two 6 can better break hard strata; and the low-density arrangement of the PDC cutting teeth one 5 allows soft strata to be cut quickly and discharged outward.

[0027] The plurality of blades 4 are divided into two groups, the top of one group of blades 4 extends as a crown wing one 41, and the top of the other group of blades 4 extends as a crown wing two 42, both the crown wing one 41 and the crown wing two 42 are fixedly connected to the crown 3, and the length of the crown wing one 41 is longer than that of the crown wing two 42; When working, the number of crown wings 41 can be three, the three crown wings 41 are arranged in a ring shape at equal intervals, and there is partial bending, so that more cutting angle friction soil bodies can be obtained, the crown wing 2 42 is shorter in length and is distributed between adjacent crown wings 41, and through the combination of different lengths, the soil body can be better cut.

[0028] The end of the crown wing 41 is fixedly connected with a bidirectional tooth 51, the bidirectional tooth 51 is a combination of a PDC cutting tooth 1 5 and a PDC cutting tooth 2 6, and the end of the crown wing 2 42 has a large slope cutting angle; When working, the bidirectional tooth 51 is further improved in cutting soil body effect in order to adapt to the shape of the end of the crown wing 1 41, and the end of the crown wing 2 42 has a more sharp excavation angle through the large slope cutting angle, so that the cutting effect is improved.

[0029] A plurality of drainage nozzles 9 are arranged at the top of the drill crown 3, a plurality of transmission valves 12 in communication with the drainage nozzles 9 are arranged at the bottom of the insertion slot 13, and a butt joint valve 10 penetrating from the bottom to the top is arranged at the bottom of the plug-in connector 2; When working, in order to ensure that the cuttings can be discharged faster, the butt joint valve 10 is communicated with the external liquid conveying equipment, liquid is injected into the bottom of the drill hole through the metal core 15, the transmission valve 12 and the drainage nozzle 9, the fluidity of the broken soil is enhanced, and the discharge of the broken soil is assisted.

[0030] The edge of the rotating drill sleeve 11 close to the PDC cutting tooth 1 5 is a detachable sharp corner block 18 structure, and the outer side of the edge is covered with a protective layer; When working, the stress of the edge position of the rotating drill sleeve 11 is increased when rotating counterclockwise, the damage caused by friction can be well reduced by arranging the sharp corner block 18 and covering the protective layer on the edge, the sharp corner block 18 can be replaced, and the sharp corner block 18 can be connected with the rotating drill sleeve 11 by means of bolt fixation.

[0031] The outer side of the PDC cutting tooth 1 5 is fixedly connected with a polishing block 17, the end of the polishing block 17 is in a sharp corner shape and faces in the opposite direction of the PDC cutting tooth 1 5, and one side of the PDC cutting tooth 2 6 installed on the blade wing 4 is also provided with a plurality of additional teeth 23; The polishing block 17 is arranged to increase the friction degree when the back of the PDC cutting tooth 1 5 contacts with the stratum rock, and in order to ensure the strength of the back of the PDC cutting tooth 1 5, a diamond layer can also be covered on the back of the PDC cutting tooth 1 5; the additional teeth 23 are bolted on the inclined surface of the blade wing 4, the damage effect on the soil layer is increased, and the assistance effect is obtained when the soil layer is dealt with.

[0032] During operation, connector 2 is connected to the drive device to control the rotation of connector 2 and drill body 1, with drill crown 3 pointing downwards to drill into the strata. When encountering strata that are relatively soft and of moderate hardness, drill body 1 rotates clockwise. At this time, the end face of PDC cutting teeth 5 contacts and cuts the strata. The design of multiple PDC cutting teeth 5 is for strata that are relatively soft and of moderate hardness, with the main differences being in volume, back slope angle, and arrangement spacing. During rotation, blade 4 and PDC cutting teeth 5 cut the soil together. At the same time, blade 4 is arc-shaped, and the resulting chip removal groove 8 is also arc-shaped. Drill body 1 and As the cutter blade 4 rotates clockwise, the cutting chips move towards the ground along the chip removal groove 8, continuously pushing the chips upwards and discharging them to the ground. This reduces the accumulation of chips at the bottom of the borehole, which would affect the drill bit's cutting operation. When encountering harder rock formations, the drive unit controls the reverse rotation of the connector 2 and the drill body 1. Since the central column 7 is composed of multiple rotating drill sleeves 11, when rotating counterclockwise, the entire cutter blade 4 will rearrange its shape under the action of friction. The rotation angle of each rotating drill sleeve 11 is limited, and when rotating clockwise, it will form a neat arc shape, such as... Figure 1 As shown, when rotated counterclockwise, it will eventually form as follows: Figure 4 As shown in the diagram, the other side of the blade 4 is engaged in frictional cutting with the stratum, while the PDC cutting tooth 6 is in direct contact with the rock. The PDC cutting tooth 6 is designed for hard strata, with improvements primarily in volume, backslope angle, and spacing. Simultaneously, due to the change in blade 4, the arc shape of the chip removal groove 8 is adapted to the counter-clockwise rotating drill body 1, allowing the rock cuttings at the bottom to continue upwards, ensuring the drill bit can continue drilling. This configuration not only achieves efficient soil cutting drilling but also, with two different cutting structures, allows the drill bit to operate efficiently in various geological environments, improving work efficiency. Furthermore, matching the appropriate cutting tooth to the appropriate stratum reduces damage to the cutting tooth and extends the drill bit's lifespan. The overall switching method is simple and convenient, requiring no removal of the drill bit from the ground or complex hydraulic control; switching is achieved simply by changing the drive direction.

[0033] To ensure smooth transmission, the locking groove 19 is inserted into the transmission device, replacing the traditional threaded connection structure. This ensures that power can be transmitted smoothly during forward and reverse transmission. The latch is used to lock the transmission device, and the horizontal groove is used to improve the transmission cross-section of both devices.

[0034] The metal core 15 is fixedly connected to the drill crown 3, and multiple rotating drill sleeves 11 are slidably sleeved on the outside, allowing the rotating drill sleeves 11 to rotate under friction and change their shape.

[0035] The connecting arm 14 and the clamping plate are inserted into the clamping groove 16, and the area of the clamping plate is greater than the outside of the clamping groove 16, so as to ensure the stability of the connection of the rotary drill sleeve 11, and the length of each group of clamping grooves 16 is different, so that each rotary drill sleeve 11 can reach the predetermined position after rotating to the limit position, and the predetermined chip groove 8 is formed, thereby ensuring the normal working process of the drill bit.

[0036] The number of the crown wing one 41 can be three, the three crown wing ones 41 are arranged in a ring shape at equal intervals, and part of the crown wing one 41 is curved, so that more cutting angle friction soil bodies can be obtained, the crown wing two 42 is short in length and is distributed between adjacent crown wing ones 41, and through the combination of different lengths, the soil bodies can be better cut.

[0037] The bidirectional tooth 51 is adapted to the shape of the end of the crown wing one 41, and further improves the cutting effect of the soil bodies, and the end of the crown wing two 42 is made of a large slope cutting angle to obtain a more sharp excavation angle, thereby improving the cutting effect.

[0038] In order to ensure that the rock debris can be discharged more quickly, the interface valve 10 is communicated with the external infusion equipment, liquid is injected into the bottom of the drill hole through the metal core 15, the transmission valve 12 and the liquid discharge nozzle 9, the flowability of the rock debris is enhanced, and the discharge of the rock debris is assisted.

[0039] When rotating counterclockwise, the edge position of the rotary drill sleeve 11 is subjected to increased stress, the sharp corner block 18 can be arranged on the edge, and a protective layer can be arranged on the edge, so that the damage caused by friction can be well reduced, the sharp corner block 18 can be replaced, and the sharp corner block 18 can be connected with the rotary drill sleeve 11 in a bolted manner.

[0040] The setting of the polishing block 17 increases the friction degree when the back surface of the PDC cutting tooth one 5 contacts with the stratum, in order to ensure the strength of the back surface of the PDC cutting tooth one 5, a diamond layer can also be arranged on the back surface of the PDC cutting tooth one 5; the additional tooth 23 is bolted on the inclined surface of the blade wing 4, the damage effect on the soil layer is increased, and the assistance effect is obtained when the soil layer is dealt with.

[0041] The above shows and describes the basic principles, main features and advantages of the present application. It should be understood by those skilled in the art that the present application is not limited to the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the present application, and various changes and improvements can be made without departing from the spirit and scope of the present application, and these changes and improvements all fall within the scope of the present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A PDC drill bit with rotatable blades having two sets of cutting structures on the upper and lower sides of the blades, characterized in that: The drill bit body is composed of a central column and a drill crown, the drill crown is located at the top of the central column, a plurality of blades are fixed to the outer side of the drill bit body, and a plurality of PDC cutting teeth one and PDC cutting teeth two are fixed to the two sides of the blades.

2. The PDC drill bit with rotatable blades having two sets of cutting structures on the upper and lower blades according to claim 1, characterized in that: The bottom of the plug-in connector is provided with two symmetrically arranged locking grooves, the inner wall of the locking groove is provided with a horizontally arranged locking hole, and the outer side of the plug-in connector is also provided with two horizontal cutting grooves.

3. The PDC drill bit with rotatable blades having two sets of cutting structures on the upper and lower blades according to claim 2, characterized in that: The top of the plug-in connector is fixedly connected with a metal core, the inner center of the central column is provided with a plug-in groove matched with the metal core, and the plurality of rotating drill sleeves are slidably connected with the metal core.

4. The PDC drill bit as claimed in claim 3, wherein the two sets of cutting structures are provided on the upper and lower sides of the rotatable blade. The inner ring of the rotating drill sleeve is fixedly connected with a plurality of connecting arms, the end of the connecting arm is fixedly connected with an arc-shaped clamping plate, and the outer surface of the metal core is provided with a plurality of clamping grooves matched with the connecting arms and the clamping plates.

5. The PDC drill bit as claimed in claim 4, wherein the two sets of cutting structures are provided on the upper and lower sides of the rotatable blade. The back rake angle of the PDC cutting tooth one is smaller than that of the PDC cutting tooth two, and the plurality of PDC cutting tooth ones and the plurality of PDC cutting tooth twos are arranged at equal intervals.

6. The PDC drill bit as claimed in claim 5, wherein the two sets of cutting structures are provided on the upper and lower sides of the rotatable blades. The plurality of blades are divided into two groups, the top of one group of blades extends into a crown wing one, and the top of the other group of blades extends into a crown wing two, the crown wing one and the crown wing two are fixed to the drill crown, and the length of the crown wing one is longer than that of the crown wing two.

7. The PDC drill bit as claimed in claim 6, wherein the two sets of cutting structures are provided on the upper and lower sides of the rotatable blade. The end of the crown wing one is fixedly connected with a bidirectional tooth, the bidirectional tooth is a combination of the PDC cutting tooth one and the PDC cutting tooth two, and the end of the crown wing two has a large slope corner.

8. The PDC drill bit as claimed in claim 7, wherein the two sets of cutting structures are provided on the upper and lower sides of the rotatable blades. The top of the drill crown is provided with a plurality of liquid discharge nozzles, the bottom of the plug-in groove is provided with a plurality of transmission valves communicated with the liquid discharge nozzles, and the bottom of the plug-in connector is provided with a plug-in valve penetrating to the top.

9. The PDC drill bit as claimed in claim 8, wherein the two sets of cutting structures are provided on the upper and lower sides of the rotatable blades. The edge of the rotating drill sleeve close to the PDC cutting tooth one is a detachable sharp corner block structure, and the outer side of the edge is covered with a protective layer.

10. The PDC drill bit of claim 9, wherein the two sets of cutting structures are provided on the upper and lower sides of the rotatable blades. The outer side of the PDC cutting tooth one is fixedly connected with a grinding block, the end of the grinding block is sharp, and the direction of the grinding block is opposite to that of the PDC cutting tooth one, and the side of the blade provided with the PDC cutting tooth two is also provided with a plurality of additional teeth.

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