CN116950570A - PDC-roller hybrid drill bit - Google Patents

Abstract

The application provides a PDC-roller hybrid drill bit, which comprises: the drill bit body is divided into a roller area and a PDC area along a plane passing through the axis of the drill bit body; the roller assembly is arranged at the lower part of the roller area and comprises a roller palm arm fixedly connected with the drill bit body, a roller shaft fixedly connected with the roller palm arm, a roller wheel arranged on the roller shaft and roller teeth fixedly arranged on the roller wheel; the PDC assembly is arranged at the lower part of the PDC region and comprises cutting teeth fixedly connected with the bit body for cutting; the oil duct is configured to enable oil in the oil cavity to flow to the contact surface of the roller shaft and the roller wheel; wherein the lower end edge of the roller tooth is lower than the lower end edge of the cutting tooth. The application has higher mechanical drilling speed and better tool surface stability, can obviously improve the mechanical drilling speed and footage, and achieves the purposes of reducing the labor intensity of workers, reducing the drilling cost and accelerating the exploration and development speed of oil-gas fields, mining sites and the like.

Description

PDC-roller hybrid drill bit

Technical Field

The application belongs to the technical field of petroleum and geological drilling tools, and particularly relates to a PDC-roller hybrid drill bit.

Background

In the fields of oil and gas drilling and geological drilling, drill bits are an indispensable downhole tool in the drilling construction process. The formation rock is broken up by the drill bit and thereby drilled, thereby forming a wellbore. The design and selection of the drill bit are key to improving the rock breaking efficiency of the complex stratum, improving the drilling speed and reducing the drilling cost. Thus, the quality of a well bore and the time taken to drill are both closely and indiscriminately related to the structure and performance of the drill bit.

PDC (polycrystalline diamond compact) drill bit can obtain better use effect in soft to medium hard stratum, so that the PDC drill bit is widely applied to petroleum and geological drilling. However, PDC bits have problems with lower rates of penetration and insufficient life in some medium to hard formations, especially in heterogeneous formations. In directional wells, horizontal wells, large displacement wells, and lateral wells, PDC bits present the problem of tool face instability, especially in small well deviations. Many times, it is desirable to orient the bit first, and the bit has a lower rate of penetration and footage in some heterogeneous hard formations. In addition, in heterogeneous stratum, especially in stratum above the middle stratum, the roller bit is easy to break, has slow mechanical drilling speed and small footage.

The prior art has PDC-cone hybrid drill bits, which have the advantages of both PDC drill bits and cone drill bits, and the use of such drill bits achieves certain results in terms of speed increase and directional efficiency improvement. However, such drill bits still suffer from short service life, low life, premature failure of the cone portion, and the like.

Disclosure of Invention

Aiming at the technical problems, the application aims to provide the PDC-roller hybrid drill bit which can greatly improve the service life, footage, mechanical drilling speed and directional characteristics of the PDC-roller hybrid drill bit in heterogeneous stratum, and is beneficial to the exploration and development of oil and gas fields and mining fields and the speed improvement and the cost reduction.

According to the present application there is provided a PDC-roller hybrid drill bit comprising: a bit body divided into a roller region and a PDC region along a plane passing through an axis thereof; the roller assembly is arranged in the roller area and comprises a roller palm arm fixedly connected with the drill bit body, a roller shaft fixedly connected with the roller palm arm, a roller wheel arranged on the roller shaft and at least one roller tooth arranged on the periphery of the roller wheel; the PDC assembly is arranged in the PDC region and comprises cutting teeth fixedly connected with the bit body and used for cutting; and the oil duct is configured to enable oil in the oil cavity to flow to the contact surface of the roller shaft and the roller wheel.

In one embodiment, a sliding piston is arranged in the oil cavity, the sliding piston divides the oil cavity into an oil chamber and a balance chamber, the oil chamber is communicated with the oil duct, and the balance chamber is communicated with the outside.

In one embodiment, a first plug is arranged at one end, far away from the sliding piston, of the oil chamber, an oil filling hole is formed in the first plug, and an oil filling plug is arranged in the oil filling hole.

In one embodiment, the oil passage comprises a first oil passage, a second oil passage and a third oil passage which are sequentially communicated, wherein the first oil passage is arranged in the roller palm arm; the second oil way is arranged along the axial direction of the roller shaft, one end of the second oil way penetrates through the roller shaft, and a second plug is arranged at the port of the second oil way; the third oil passage is arranged along the radial direction of the roller shaft.

In one embodiment, the roller assembly further includes sealing assemblies provided at both ends of the roller shaft for preventing leakage of oil.

In one embodiment, the roller assembly further comprises a shaft seat disposed on the bit body, and an end of the roller shaft distal from the roller palmar arm is disposed within the shaft seat.

In one embodiment, the sealing assembly comprises a first end face sealing ring and an elastic sealing ring which are sleeved on the roller shaft and mutually abutted, and the elastic sealing ring is close to the end of the roller shaft.

In one embodiment, the end face seal ring is made of metal, metal coated tungsten carbide, ceramic, cemented carbide, diamond, cubic boron nitride or silicon nitride; the axle seat, the roller palm and the sealing surface of the roller wheel are made of nitriding, carburizing, carbonitriding, boronizing, tungsten carbide coating or ceramic materials.

In one embodiment, the sealing assembly further comprises a second end face sealing ring sleeved on the roller shaft, and the second end face sealing ring is abutted with the first end face sealing ring.

In one embodiment, the lower end edge of the cutting tooth is located between the lower end edge of the roller tooth and the lower end edge of the roller wheel.

Compared with the prior art, the application has the advantages that:

the PDC-roller hybrid drill bit provided by the application combines the roller component and the PDC component, has higher mechanical drilling speed and better tool face stability, can obviously improve the mechanical drilling speed and footage, and achieves the purposes of reducing the labor intensity of workers, reducing the drilling cost and accelerating the exploration and development speeds of oil-gas fields, mining fields and the like. In the working process of the PDC-roller hybrid drill bit, stratum rock is firstly crushed by utilizing roller teeth in a roller assembly, defects such as cracks are formed in an uncrushed stratum, the crushing strength of the stratum rock is reduced, and then the stratum rock is cut through cutting teeth in the PDC assembly. On one hand, the roller teeth are only used for pre-treating and crushing the rock at the bottom of the well, so that the workload and the stress of the roller teeth are greatly reduced. On the other hand, the cutting teeth in the PDC assembly cut weakened stratum rock, so that the drillability of the stratum rock is greatly improved, and the stress of the cutting teeth is greatly improved. Therefore, the service lives of the roller assemblies and the PDC assemblies are greatly prolonged. Meanwhile, the roller teeth on the rolling wheels are arranged at intervals, and the PDC-roller hybrid drill bit can generate periodic vibration along the axial direction of the drill bit body through the rolling of the rolling wheels, so that the stability of a working face and the transmission efficiency of the weight on bit are very favorable, the stability of a tool face of drilling of the PDC-roller hybrid drill bit is further promoted, and the drilling operation efficiency of the drill bit is very favorable and the drilling effect is enhanced. According to the application, the contact part of the roller shaft and the rolling wheel is provided with the lubricating oil, so that the service life of the rolling assembly is further prolonged.

Drawings

The present application will be described below with reference to the accompanying drawings.

FIG. 1 schematically illustrates the construction of a PDC-roller hybrid drill bit in accordance with the present application;

FIG. 2 is an enlarged schematic view of the portion A in FIG. 1;

FIG. 3 is an enlarged schematic view of the portion B of FIG. 2;

FIG. 4 schematically illustrates the configuration of the working face of the PDC-roller hybrid drill bit of FIG. 1.

In the present application, all of the figures are schematic drawings which are intended to illustrate the principles of the application only and are not to scale.

Detailed Description

The application is described below with reference to the accompanying drawings.

In the present application, directional terms or qualifiers "upper" and "lower" used in the present application are used with reference to fig. 1. They are not intended to limit the absolute position of the parts involved, but may vary according to the specific circumstances.

Fig. 1 schematically shows the structure of a PDC-roller hybrid drill bit 100 according to the present application. As shown in fig. 1, the PDC-roller hybrid drill bit 100 includes a bit body 1, a roller assembly 3, and a PDC assembly 4. The bit body 1 is generally cylindrical in shape, and the upper end of the bit body 1 is configured with a connection sub 2 for connection to a drill string (not shown) that drives rotation of the bit body 1. The bit body 1 is divided into two parts, a roller zone 11 and a PDC zone 12, by a plane passing through its axis. The roller assembly 3 is mounted at a lower portion of the roller region 11 and faces the working end surface. In this embodiment, the roller assembly 3 includes a roller palm 31 fixedly connected to the bit body 1, a roller shaft 32 fixedly connected to the roller palm 31, a roller wheel 33 mounted on the roller shaft 32, and roller teeth 34 embedded on the roller wheel 33. The rolling teeth 34 include at least one and are uniformly disposed along the circumferential surface of the rolling wheel 33. An oil chamber 311 and an oil passage 312 are provided in the roller palm 31. The oil chamber 311 is filled with lubricating oil, the oil passage 312 communicates with the oil chamber 311, and the oil in the oil chamber 311 can flow along the oil passage 312 between the contact surfaces of the roller shaft 32 and the roller wheel 33. With this arrangement, on the one hand, friction between the roller wheel 33 and the roller shaft 32 is reduced, and the service life of the roller assembly 3 is prolonged. On the other hand, the gap between the roller wheel 33 and the roller shaft 32 is filled with oil, so that broken stone is prevented from entering during operation, and the roller wheel 33 or the roller shaft 32 is damaged. The PDC assembly 4 is disposed in a lower portion of the PDC region 12 with the PDC assembly 4 facing the working face. The PDC assembly 4 includes blades 41 and cutting teeth 42 embedded on the blades 41. Wherein the lower end edge of the cutting tooth 42 is located between the lower end edge of the roller tooth 34 and the lower end edge of the roller wheel 33. Thus, the PDC-roller hybrid bit 100 is formed by the roller assembly 3 and the PDC assembly 4. The working end face here means the rock surface to be crushed and cut, and the lower end edge here means the lowermost end in the axial direction of the PDC-roller hybrid drill bit 100.

In operation, the PDC-roller hybrid drill bit 100 rotates along its axis with the working end face facing the formation to be drilled, and can pre-process broken formation rock through the roller assembly 3, and form defects such as cracks in the unbroken formation, so as to reduce the breaking strength of the formation rock, and further cut the formation rock after pre-breaking, breaking up the cracks, weakening through the PDC assembly 4. That is, as the PDC-roller hybrid drill bit 100 rotates along its axis, the roller wheel 33 rotates about the roller shaft 32 under the friction of the formation. The roller wheel 33 intermittently contacts the formation during rotation, thereby causing the PDC-roller hybrid drill bit 100 to vibrate periodically along its axis. Since the lower end edge of the roller tooth 34 is lower than the lower end edge of the cutting tooth 42, the cutting tooth 42 is not in contact with the ground when the roller tooth 34 is in contact with the ground. At this point, the roller teeth 34 fracture the formation pretreatment. When the roller wheel 33 rotates until the roller teeth 34 are not in contact with the formation, the cutting teeth 42 are in contact with the formation. At this time, the cutting teeth 42 cut the formation. So that the drilling work is periodically performed.

Thus, on the one hand, the working capacity and the stress of the roller assembly 3 are greatly reduced by partially and partially crushing the rock at the bottom of the well, and the friction between the roller shaft 32 and the roller wheel 33 is further reduced and the service life is prolonged by arranging the oil cavity 311 and the oil duct 312. On the other hand, the cutting teeth 42 of the PDC assembly 4 cut weakened formation rock, the formation rock drillability is greatly improved, and the stress of the cutting teeth 2 is greatly improved, which greatly improves the service lives of the roller assembly 3 and the PDC assembly 4. Meanwhile, the rolling wheels 33 roll to generate periodic axial vibration and transmit the periodic axial vibration into a drill string, so that the stability of a working surface of a directional well and the transmission efficiency of weight on bit are effectively improved, the footage, the mechanical drilling speed and the directional characteristic in a heterogeneous stratum can be greatly improved, and the method is very beneficial to the speed increase and the cost reduction of exploration and development of oil and gas fields and mining fields.

In a preferred embodiment, the lower end edge of the lower end edge wall cutter 42 of the roller tooth 34 is 0.01-5 mm lower. In this vibration range, the work efficiency is high.

In one embodiment, the connection sub 2 at the upper end of the bit body 1 may be configured as a tapered connection button and fixedly connected to the drill string by a threaded connection. Meanwhile, a shackle groove 21 is also circumferentially provided on the outer wall of the conical connecting shackle for achieving rapid disassembly between the PDC-roller hybrid drill bit 100 and the upper drill string. Through this kind of structure, bit body 1 not only easy to assemble connects, convenient to detach moreover can show improvement dismouting efficiency.

The roller assemblies 3 and PDC assemblies 4 may be staggered or adjacently disposed, and in a preferred embodiment are disposed in radially opposed relation.

In a specific embodiment, as shown in FIG. 2, the oil chamber 311 is configured to be cylindrical. The inside of the oil chamber 311 is sealingly provided with a sliding piston 313 movable in the axial direction of the oil chamber 311. The sliding piston 313 divides the oil chamber 311 into a balance chamber 314 and an oil chamber 315. The oil chamber 315 is filled with oil, and is communicated with the oil passage 312, and the balance chamber 314 is communicated with the outside. By this arrangement, after the oil in the oil chamber 315 is lost during operation, the sliding piston 313 moves toward the oil chamber 315 under the action of atmospheric pressure, thereby ensuring that the oil in the oil chamber 315 smoothly flows between the roller shaft 32 and the roller wheel 33.

In a specific embodiment, a first plug 316 is disposed at an end of the oil chamber 315 away from the sliding piston 313, an oil filling hole 317 is formed on the first plug 316, and an oil filling plug 318 is disposed in the oil filling hole 317. With this arrangement, after the oil is absent from the oil chamber 315, the oil filler plug 318 can be removed from the oil filler hole 317 and oil can be injected into the oil chamber 315 through the oil filler hole 317.

In a preferred embodiment, the oil passage 312 includes a first oil passage 301 provided in the roller palm 31, a second oil passage 302 provided in the roller shaft 32, and a third oil passage 303. One end of the first oil passage 301 communicates with the oil chamber 315, and the other end communicates with the second oil passage 302. The second oil passage 302 is provided along the axial direction of the roller shaft 32. One end of the second oil path 302 passes through the roller shaft 32 to form an opening, and the other end is closed by the roller shaft 32. A second plug 323 is provided at an end of the second oil passage 302 that opens. The third oil passage 303 is disposed along a radial direction of the roller shaft 32, and is used for guiding oil to a contact surface of the roller shaft 32 and the roller wheel 33. With this arrangement, the oil passage 312 is conveniently machined, and only a simple drilling process is required.

In a specific embodiment, the roller assembly further includes an axle seat 35. The shaft seat 35 is fixedly arranged on the bit body 1, and one end of the roller shaft 32, which is far away from the roller palm arm 31, is arranged in the shaft seat 35. With this arrangement, stability of the roller shaft 32 is enhanced.

According to the present application, the roller shaft 32 is provided with a seal assembly 6 for preventing oil leakage. The seal assembly 6 is provided with two sets, one at each end of the roller shaft 32. With one set of seal assemblies 6 illustrated, as shown in fig. 3, the seal assemblies 6 include a first end seal ring 61 and a resilient seal ring 62. The first end face seal ring 61 and the elastic seal ring 62 are both sleeved on the roller shaft 32 and abut against each other. The elastic seal 62 is adjacent to the end of the roller shaft 32 and the first end face seal 61 is adjacent to the third oil passage 303. In this way, the sealing of the oil is achieved.

In a specific embodiment, the shaft seat 35 and the sealing surfaces of the roller palm 31 and the roller wheel 33, and the roller shaft 32 are nitrided, carburized, carbonitriding, boronized, tungsten carbide coated, or made of a corresponding material, or made of a ceramic material. By this arrangement, friction is reduced, and the tightness between the shaft seat 35 and the end face of the roller wheel 33 and the tightness between the roller wheel 33 and the roller palm 31 are increased.

In a preferred embodiment, the seal assembly 6 further comprises a second end seal 63. The second end face seal 63 is also fitted over the roller shaft 32 and abuts the first end face seal 31. With this arrangement, the tightness of the oil is further enhanced.

In a preferred embodiment, the first face seal 61 and the second face seal 63 are made of metal, metal coated tungsten carbide, ceramic, cemented carbide, diamond, cubic boron nitride, or silicon nitride. By this arrangement, the service life can be prolonged.

According to the present application, as shown in fig. 1, the roller palms 31 are fixedly connected to the outer wall of the bit body 1. For example, the roller palms 31 may be secured to the outer wall of the bit body 1 by welding.

In a preferred embodiment, the roller axle 32 is integrally provided with the roller palm 31. The angle between the roller shaft 32 and the roller palm 31 is an obtuse angle, and the roller shaft 32 is arranged to extend inwards and downwards. Thereby, the rolling wheel 33 is directed toward the working end face.

In one embodiment, the contour of the roller 32 is an arc with a high middle and low sides. The roller teeth 34 are embedded in the middle of the roller wheel 33 and are circumferentially arranged. The number of the roller teeth 34 is plural, and the plurality of roller teeth 34 are uniformly distributed in the circumferential direction. This configuration of the roller assembly 3 is very advantageous for breaking formation rock. The roller wheel 33 is mounted on the roller shaft 32 and forms a rotational connection with the roller shaft 32.

According to one embodiment of the application, the contact surface of the roller wheel 33 with the roller shaft 32 constitutes a sliding bearing, so that the two form a rotational connection. Preferably, an intermediate sliding sleeve or the like can be added between the sliding bearing surfaces. This can greatly increase the service life of the roller wheel 33, thereby facilitating an increase in the service life of the PDC-roller hybrid drill bit 100.

According to the application, the roller teeth 34 are configured as first profiled teeth. The first special-shaped teeth can be special-shaped tooth structures such as bevel teeth, wedge teeth, spherical teeth, spoon teeth or oval teeth. The roller teeth 34 may be made of cemented carbide, ceramic or PDC material. This can significantly improve the adaptation of the roller assembly 3 to the formation rock.

According to the present application, as shown in fig. 1, a first diameter-keeping tooth 332 is provided on the outer wall of the roller palm 31, and the first diameter-keeping tooth 332 is fitted on the outer wall surface of the roller palm 31. Meanwhile, in a preferred embodiment, roller repair teeth 331 are further provided on the radially outermost contour of the roller 33. Therefore, the diameter of the hole drilled by the PDC-roller mixed drill bit 100 in the drilling process can be effectively protected from being reduced through the first diameter-keeping teeth 332 and the roller diameter-repairing teeth 331, so that the drilling performance and the directional performance of the PDC-roller mixed drill bit 100 are ensured.

According to the application, the PDC assembly 4 further comprises a gage block 43 formed radially outwardly of the blades 41, a second gage tooth 431 being provided in the gage block 43, the second gage tooth 431 being mounted in-line on the gage block 43.

The blade 41 is coated on the bit body 1, and the gage block 43 is preferably integrally provided with the blade 41. For example, a portion of the radially outer side of blade 41 is formed as gage block 43.

As shown in fig. 1, an active gage tooth 44 may be further disposed on the gage block 43, where the active gage tooth 44 is disposed between the second gage tooth 431 and the cutting tooth 44, and a maximum outer diameter of the active gage tooth 44 is equal to or greater than a maximum outer diameter of the second gage tooth 431. Therefore, the first diameter-keeping teeth 332, the roller diameter-repairing teeth 331, the second diameter-keeping teeth 431 and the active diameter-keeping teeth 44 act together, so that the diameter of a hole drilled by the PDC-roller hybrid drill bit 100 in the drilling process can be effectively protected from being reduced, and the drilling performance and the directional performance of the PDC-roller hybrid drill bit 100 are further ensured.

The PDC assembly 4 is made of PDC (polycrystalline diamond compact) material according to the present application. That is, the blade 41, the cutting teeth 42, the gage blocks 43, the second gage teeth 431, and the active gage teeth 44 are all made of PDC (polycrystalline diamond compact) material. This effectively ensures the strength of the PDC assembly 4, and thus the cutting performance of the PDC-roller hybrid drill bit 100.

Preferably, the cutting teeth 42 may be configured as shaped teeth such as planar teeth, conical teeth, ridged teeth, and triangular teeth. This can further improve the cutting performance of the PDC-roller hybrid drill bit 100.

According to one embodiment of the present application, as shown in fig. 4, a first auxiliary cutting tooth 10 may be provided on the blade 41, the first auxiliary cutting tooth 10 being located behind the cutting tooth 42. Preferably, the blade 41 may also be provided with the second auxiliary cutting teeth 7. Likewise, the second auxiliary cutting teeth 7 are located after the cutting teeth 42, and the second auxiliary cutting teeth 7 and the first cutting teeth 10 are distributed spaced apart from each other in the radial direction. It should be understood that the front and rear refer to the sequence in which the cutting teeth 42 encounter the formation during rotation of the bit body 1, and that the cutting teeth 42 are later than the side of the cutting teeth 42 that contact the formation rock.

The first auxiliary cutting teeth 10 and the second auxiliary cutting teeth 7 are made of cemented carbide, ceramic or PDC materials.

According to the present application, as shown in fig. 1, a central flow passage 8 and a nozzle 9 extending in the axial direction are provided in the interior of the bit body 1. The central flow passage 8 and the nozzles 9 extend through the bit body 1, forming a drilling fluid flow passage. The nozzle 9 is angled with respect to the central flow passage 8 so that the nozzle 9 is aligned with the working end face. Drilling fluid from the drill string can be directed through the central flow passage 8 and nozzle jets 9 in sequence to the surface of the formation rock to which the PDC-roller hybrid drill bit 100 is directed. On the one hand, the drilling fluid sprayed by the nozzles 9 is able to strike and soften the formation rock. On the other hand, the drilling fluid sprayed by the nozzle 9 can clean the roller assembly 3 and the PDC assembly 4, so that the drill cuttings are effectively prevented from adhering to the rolling wheel 33 or the cutter blades 41, the mechanical drilling speed of the PDC-roller hybrid drill bit 100 is improved, and the drilling performance of the PDC-roller hybrid drill bit 100 is guaranteed.

A plurality of nozzles 9 may be provided in the bit body 1 to ensure the flow through effect and efficiency of the drilling fluid and to ensure cleaning and cooling of the roller assemblies 3 and PDC assemblies 4.

In the description of the present application, it should be understood that the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

In the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Finally, it should be noted that the above description is only of a preferred embodiment of the application and is not to be construed as limiting the application in any way. Although the application has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the techniques described in the foregoing examples, or equivalents may be substituted for elements thereof. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims (10)

1. A PDC-roller hybrid drill bit, comprising:

a bit body (1), the bit body (1) being divided into a roller zone and a PDC zone along a plane passing through an axis thereof;

the roller assembly (3) is arranged in the roller area, the roller assembly (3) comprises a roller palm arm (31) fixedly connected with the drill bit body (1), a roller shaft (32) fixedly connected with the roller palm arm (31), a roller wheel (33) arranged on the roller shaft (32), and at least one roller tooth (34) arranged on the periphery of the roller wheel (33);

a PDC assembly disposed in the PDC region, the PDC assembly including cutting teeth (42) fixedly coupled to the bit body (1) for cutting;

an oil chamber (311) and an oil passage (312) are provided in the roller palm (31), the oil passage (312) being configured to enable oil in the oil chamber (311) to flow to the contact surface of the roller shaft (32) and the roller wheel (33).

2. The PDC-roller hybrid drill bit of claim 1, wherein a sliding piston (313) is disposed within the oil chamber (311), the sliding piston (313) dividing the oil chamber (311) into an oil chamber (315) and a balance chamber (314), the oil chamber (315) being in communication with the oil passage (312), the balance chamber (314) being in communication with the outside.

3. The PDC-roller hybrid drill bit of claim 2, wherein a first plug (316) is disposed at an end of the oil chamber (315) away from the sliding piston (313), an oil filling hole (317) is formed in the first plug (316), and an oil filling plug (318) is disposed in the oil filling hole (317).

4. The PDC-roller hybrid drill bit of claim 3 wherein the oil passage (312) comprises a first oil passage (301), a second oil passage (302) and a third oil passage (303) in sequential communication, wherein,

the first oil way (301) is arranged in the roller palm arm (31);

the second oil way (302) is arranged along the axial direction of the roller shaft (32), one end of the second oil way (302) penetrates through the roller shaft (32), and a second plug (323) is arranged at a port of the second oil way (302);

the third oil passage (303) is arranged along the radial direction of the roller shaft (32).

5. The PDC-roller hybrid drill bit of claim 4 wherein the roller assembly (3) further comprises a seal assembly disposed at both ends of the roller shaft (32) for preventing oil leakage.

6. The PDC-roller hybrid drill bit of claim 5 wherein the roller assembly (3) further comprises an axle seat (35) disposed on the bit body (1), an end of the roller axle (32) distal from the roller palmar arm (31) disposed within the axle seat (35).

7. The PDC-roller hybrid drill bit of claim 6 wherein the seal assembly includes a first end seal ring (61) and an elastomeric seal ring (62) that are nested on the roller shaft (32) in abutment with each other, the elastomeric seal ring (62) being proximate an end of the roller shaft (32).

8. The PDC-roller hybrid drill bit of claim 7 wherein the face seal ring is fabricated from metal, metal coated tungsten carbide, ceramic, cemented carbide, diamond, cubic boron nitride, or silicon nitride; the axle seat (35) and the sealing surfaces of the roller palm arm (31) and the roller wheel (33) and the roller shaft are made of nitriding, carburizing, carbonitriding, boronizing, tungsten carbide coating or ceramic materials.

9. The PDC-roller hybrid drill bit of claim 8 wherein the seal assembly further comprises a second face seal ring (63), the second face seal ring (63) is sleeved on the roller shaft (32), and the second face seal ring (63) abuts the first face seal ring (61).

10. The PDC-roller hybrid drill bit of any of claims 1-9, wherein a lower end edge of the cutter teeth (42) is located between a lower end edge of the roller teeth (34) and a lower end edge of the roller wheel (33).