Active pressure relief anti-blocking composite coring bit special for deep stratum
The composite coring drill bit with active pressure relief and anti-clogging mechanism for deep buried formations, featuring an inner and outer double-layer structure, solves the problem of difficult coring in deep buried formations and achieves the functions of preventing drill bit clogging and backflushing the borehole, demonstrating significant technical advantages.
Patent Information
- Application Number
- CN202520129662.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-20
- Publication Date
- 2025-12-16
- Estimated Expiration
- 2035-01-20
AI Technical Summary
Core sampling is difficult in deeply buried strata, and the unreasonable structure of existing coring drill bits leads to drill bit blockage, resulting in coring failure.
The composite coring drill bit for deep buried formations with active pressure relief and anti-clogging features a double-layer structure. It breaks rock with the pressure-relieved outer drill bit and extracts the core with the inner drill bit. A slip ring is installed between the inner and outer drill bits to achieve high-pressure water backwashing of the borehole.
It effectively prevents drill bit blockage and enables successful coring in deeply buried strata, demonstrating significant technological advantages and market potential.
Smart Images
Figure CN223676176U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to stratum drilling technology field, concretely relates to a deep buried stratum special initiative pressure relief anti -block composite coring drill bit. BACKGROUND
[0002] Deep buried stratum is generally high in stress, and it is difficult to take cores, and the reason is that the rock mass is in a compression deformation state in situ, and the rock core taken out under the disturbance of the rotary cutting of the coring drill bit releases stress and expands and deforms instantaneously, which leads to the blockage of the coring drill bit with a high probability, and further causes the failure of taking cores in the deep buried stratum. After analysis, it is found that the structure of the coring drill bit is unreasonable. Therefore, it is urgent to improve the existing coring drill bit. CONTENT OF UTILITY MODEL
[0003] In order to solve the above technical problems existing in the prior art, the utility model provides a deep buried stratum special initiative pressure relief anti -block composite coring drill bit, the coring drill bit is improved into an inner-outer double-layer structure, wherein the outer drill bit breaks rock and relieves pressure, and the inner drill bit takes cores and prevents blockage. In addition, a slip ring is arranged between the inner drill bit and the outer drill bit to achieve the purpose of high-pressure water supply backwashing of the drill hole.
[0004] To solve the above technical problems, the utility model adopts the following technical scheme: a deep buried stratum special initiative pressure relief anti -block composite coring drill bit, which comprises a pressure relief outer drill bit and a coring inner drill bit, both of which are hollow structures and are vertically permeable, the pressure relief outer drill bit is coaxially arranged inside the pressure relief outer drill bit, the outer circle of the upper part of the coring inner drill bit is threadedly connected with the inner circle of the upper part of the pressure relief outer drill bit, and the uppermost end of the coring inner drill bit is lower than the uppermost end of the pressure relief outer drill bit; a pressure relief cavity with an open top is formed above the threaded connection part between the coring inner drill bit and the pressure relief outer drill bit, a water injection pressure bearing cavity in the shape of a ring is formed below the threaded connection part between the coring inner drill bit and the pressure relief outer drill bit, a pressure relief hole is formed in the upper part of the pressure relief outer drill bit and is in communication with the pressure relief cavity, a water outlet hole is formed in the lower part of the pressure relief outer drill bit and is in communication with the water injection pressure bearing cavity, a pressure bearing sliding assembly is arranged in the water injection pressure bearing cavity, and the inner thread section in the lower part of the inner circle of the pressure relief outer drill bit is connected with a sealed coring device or a rock core tube.
[0005] The pressure relief outer drill bit comprises an outer drill handle, the inner circle of the upper part of the outer drill handle is provided with an upper inner thread section which is threadedly connected with the coring inner drill bit, the outer drill handle is a conical cylinder section which is large at the top and small at the bottom above the upper thread section, a plurality of outer cutting teeth are uniformly arranged on the upper end of the conical cylinder section in the circumferential direction, the pressure relief hole is formed on the conical cylinder section, the water outlet hole is formed in the lower part of the outer drill handle and is located above the lower inner thread section, and the center line of the water outlet hole is arranged in an inclined manner with the inner part being higher than the outer part.
[0006] The core taking inner drill bit comprises an inner drill shank, an outer thread section arranged on the upper portion of the inner drill shank, a plurality of inner cutting teeth arranged on the upper end of the inner drill shank in the circumferential direction, and a gas guide groove arranged on the inner wall of the inner drill shank.
[0007] The pressure-bearing sliding assembly comprises a pressure-bearing sliding ring arranged in the water injection pressure-bearing cavity and a spring arranged above the pressure-bearing sliding ring.
[0008] The core taking inner drill bit is inserted into the inner portion of the pressure relief outer drill bit, and the outer thread section of the upper portion of the inner drill shank is threadedly connected with the upper inner thread section of the upper portion of the outer drill shank.
[0009] The gas guide groove is arranged on the upper portion of the inner wall of the inner drill shank, so that the pressure-bearing gas stored in the inner drill shank is discharged upward through the gas guide groove in the core taking process (when the rock core blocks the drill bit).
[0010] When high pressure water is not injected, the pressure bearing sliding ring is in the state of blocking the water outlet hole under the resistance of the spring. The water outlet hole is inclined with the center line being high and the outer being low, so that the water flow shot through the water outlet hole has downward kinetic energy, and the deslagging effect is better.
[0011] In summary, the utility model principle science, simple structure, adopts the double layer structure of external rock breaking, pressure relief and internal coring, preventing blockage, backwashing drilling function in the process of taking core in deep stratum, has the significant technical advantage and market potential, easy to popularization and application. BRIEF DESCRIPTION OF DRAWINGS
[0012] Figure 1 It is the structure schematic diagram of the utility model;
[0013] Figure 2 It is the top view of Figure 1 ;
[0014] Figure 3 It is the external structure schematic diagram of the pressure relief outer drill bit;
[0015] Figure 4 It is the A-A section view of Figure 3 ;
[0016] Figure 5 It is the external structure schematic diagram of the pressure relief inner drill bit;
[0017] Figure 6 It is the B-B section view of Figure 5 ;
[0018] Figure 7 It is the structure schematic diagram of the pressure bearing sliding ring. DETAILED DESCRIPTION
[0019] The embodiment of the utility model is further described in detail below in combination with the drawings and examples.
[0020] As Figures 1-7As shown, the deep buried stratum special active pressure relief anti-blocking composite coring drill bit of the utility model, including all be hollow structure, upper and lower penetration's pressure relief outer drill bit 1 and coring inner drill bit 2, pressure relief outer drill bit 1 and coaxial direction be equipped with in pressure relief outer drill bit 1 inside coring inner drill bit 2, coring inner drill bit 2 upper portion outer circle and pressure relief outer drill bit 1 upper portion inner circle screw thread connection, coring inner drill bit 2 the most upper end is lower than the most upper end of pressure relief outer drill bit 1;Coring inner drill bit 2 and pressure relief outer drill bit 1 between in screw thread connection portion 7 top forms the pressure relief cavity 3 of top open, coring inner drill bit 2 and pressure relief outer drill bit 1 between in screw thread connection portion 7 below forms the annular injection water pressure bearing cavity 4, pressure relief outer drill bit 1 upper portion is equipped with with pressure relief cavity 3 intercommunication's pressure relief hole 5, pressure relief outer drill bit 1 lower portion is equipped with with injection water pressure bearing cavity 4 intercommunication's water outlet hole 6, injection water pressure bearing cavity 4 is equipped with pressure bearing sliding assembly, pressure relief outer drill bit 1 inner circle lower portion is equipped with with airtight coring device or core tube (existing coring tool) connection's lower inner thread section 8.
[0021] Pressure relief outer drill bit 1 includes outer drill handle 9, and the upper inner thread section 10 of the upper inner circle of outer drill handle 9 is equipped with with coring inner drill bit 2 screw thread connection, and the upper screw thread section of outer drill handle 9 is above the large lower small conical cylinder section, and the upper end of the conical cylinder section is evenly provided with a plurality of outer cutting teeth 11 along the circumferential direction, and the pressure relief hole 5 is arranged on the conical cylinder section, and the water outlet hole 6 is arranged on the lower portion of the outer drill handle 9 and is located above the lower inner thread section 8, and the center line of the water outlet hole 6 is inclinedly arranged with the high inside and the low outside.
[0022] Coring inner drill bit 2 includes inner drill handle 12, and the outer thread section 13 of the upper outer circle of inner drill handle 12 is equipped with with upper inner thread section 10 screw thread connection, and the upper end of inner drill handle 12 is evenly provided with a plurality of inner cutting teeth 14 along the circumferential direction, and the inner diameter of inner drill handle 12 gradually increases by 0.5-5 mm from top to bottom, and the inner circle of the upper end of inner drill handle 12 is vertically provided with a gas guide groove 15, and the upper end of the gas guide groove 15 is flush with the upper end of inner drill handle 12, and the outer circle of the lower end of inner drill handle 12 is provided with a circular groove 16 for mounting and fixing a sealing ring along the circumferential direction.
[0023] The pressure bearing sliding assembly includes a pressure bearing sliding ring 17 and a spring 18 arranged in the injection water pressure bearing cavity 4, the spring 18 is located above the pressure bearing sliding ring 17, the inner diameter of the pressure bearing sliding ring 17 is greater than the outer diameter of the inner drill handle 12 by 0.1-0.5 mm, and the outer diameter of the pressure bearing sliding ring 17 is smaller than the inner diameter of the lower portion of the outer drill handle 9 by 0.1-0.5 mm; The outer circle and the inner circle of the pressure bearing sliding ring 17 are both provided with an annular sealing groove 19, each annular sealing groove 19 is mounted with a sliding sealing ring 20, the inner sliding sealing ring 20 is in sliding sealing cooperation with the outer circle of the inner drill handle 12, and the outer sliding sealing ring 20 is in sliding sealing cooperation with the inner circle of the outer drill handle 9.
[0024] In this invention, during coring operations, the inner core drill bit 2, with a fixed sealing ring on its lower outer circumference, is first inserted into the pressure-relieving outer drill bit 1. The inner core drill bit 2 is rotated so that the external thread section 13 on the upper part of the inner drill shank 12 is threadedly connected to the upper internal thread section 10 on the upper part of the outer drill shank 9. Then, the spring 18 and the pressure-bearing slip ring 17 with a sliding sealing ring 20 are sequentially installed into the water-injection pressure-bearing cavity 4. Next, the upper end of the sealed core sampling device or core tube is inserted into the lower port of the water-injection pressure-bearing cavity 4. The outer circumference of the upper port of the sealed core sampling device or core tube is threadedly connected to the lower internal thread section 8 on the lower part of the outer drill shank 9. The fixed sealing ring on the outer circumference of the inner drill shank 12 seals the inner circumference of the upper port of the sealed core sampling device or core tube, ensuring that the water outlet at the upper end of the sealed core sampling device or core tube is aligned with the water-injection pressure-bearing cavity 4, and that a pressurized water section is formed inside the water-injection pressure-bearing cavity 4. Next, core drilling begins under conditions of no water supply. The outer cutting tooth 11 at the upper end of the outer drill shank 9 first drills the formation, and a large amount of rock cuttings will accumulate in the pressure relief chamber 3. The rock cuttings are discharged from the drill bit through the pressure relief hole 5, creating a "pressure relief effect". Due to the rotary cutting action of the outer cutting tooth 11, a large rock column without pressure is formed. Immediately afterwards, the inner cutting tooth 14 rotary cuts the formed pressure-relieved rock column. The rock column is squeezed into the upper port of the inner drill shank 12. The inner hole of the inner drill shank 12 is narrow at the top and wide at the bottom, so it can smoothly enter the sealed coring device or the core tube. After the composite coring drill bit advances forward by 0.5~1m, high-pressure water is supplied through the sealed coring device or the core tube. The high-pressure water enters the water injection pressure chamber 4, pushing the pressure-bearing slip ring 17 to move upward. The pressure-bearing slip ring 17 no longer blocks the water outlet hole 6, and the high-pressure water is sprayed outward through the water outlet hole 6 to flush out the rock cuttings remaining on the outside of the drill bit, so as to prevent the drill bit from getting stuck.
[0025] The above embodiments illustrate the basic principles and features of this utility model. However, the above descriptions are merely preferred embodiments and are not limited to these embodiments. Those skilled in the art, inspired by this patent, can make many modifications and improvements without departing from the spirit and scope of the claims, all of which fall within the protection scope of this utility model. Therefore, the patent and its scope of protection should be determined by the appended claims.
Claims
1. A deep buried stratum special active pressure relief anti-clogging composite coring bit, characterized in that: The pressure relief outer drill bit and the coring inner drill bit are both hollow structures and are vertically penetrable, the pressure relief outer drill bit and the coaxially arranged coring inner drill bit are threadedly connected at the upper outer circle of the coring inner drill bit and the upper inner circle of the pressure relief outer drill bit, the uppermost end of the coring inner drill bit is lower than the uppermost end of the pressure relief outer drill bit, a pressure relief cavity with an open top is formed above the threaded connection part between the coring inner drill bit and the pressure relief outer drill bit, a circular annular water injection pressure bearing cavity is formed below the threaded connection part between the coring inner drill bit and the pressure relief outer drill bit, a pressure relief hole is arranged in the upper part of the pressure relief outer drill bit and is in communication with the pressure relief cavity, a water outlet hole is arranged in the lower part of the pressure relief outer drill bit and is in communication with the water injection pressure bearing cavity, a pressure bearing sliding assembly is arranged in the water injection pressure bearing cavity, and a lower inner threaded section connected with a sealed coring device or a core tube is arranged in the lower part of the inner circle of the pressure relief outer drill bit. 2. The deep formation dedicated active pressure-relief anti-clogging composite coring bit of claim 1, wherein: The pressure relief outer drill bit comprises an outer drill shank, an upper inner threaded section for threadedly connecting with the coring inner drill bit is arranged in the upper inner circle of the outer drill shank, the outer drill shank is a conical cylinder section with a large upper part and a small lower part above the upper threaded section, a plurality of outer cutting teeth are uniformly arranged on the upper end of the conical cylinder section in the circumferential direction, the pressure relief hole is arranged on the conical cylinder section, and the water outlet hole is arranged in the lower part of the outer drill shank and is located above the lower inner threaded section, and the center line of the water outlet hole is arranged in an inclined manner with a high inner part and a low outer part.
3. The deep formation dedicated active pressure-relief anti-clogging composite coring bit of claim 2, wherein: The coring inner drill bit comprises an inner drill shank, an outer threaded section for threadedly connecting with the upper inner threaded section is arranged in the upper outer circle of the inner drill shank, a plurality of inner cutting teeth are uniformly arranged on the upper end of the inner drill shank in the circumferential direction, the inner diameter of the inner drill shank gradually increases by 0.5-5 mm from the upper part to the lower part, a gas guide groove is vertically arranged on the inner circle of the upper end port of the inner drill shank, the upper end port of the gas guide groove is flush with the upper end of the inner drill shank, and a circular groove for mounting and fixing a sealing ring is arranged on the outer circle of the lower end of the inner drill shank in the circumferential direction.
4. The deep formation dedicated active pressure-relief anti-clogging composite coring bit of claim 3, wherein: The pressure bearing sliding assembly comprises a pressure bearing sliding ring arranged in the water injection pressure bearing cavity and a spring, the spring is located above the pressure bearing sliding ring, the inner diameter of the pressure bearing sliding ring is greater than the outer diameter of the inner drill shank by 0.1-0.5 mm, and the outer diameter of the pressure bearing sliding ring is smaller than the inner diameter of the lower part of the outer drill shank by 0.1-0.5 mm; the outer circle and the inner circle of the pressure bearing sliding ring are both provided with annular sealing grooves, a sliding sealing ring is mounted in each annular sealing groove, the inner sliding sealing ring is in sliding sealing cooperation with the outer circle of the inner drill shank, and the outer sliding sealing ring is in sliding sealing cooperation with the inner circle of the outer drill shank.