CN110500041A - A self-propelled jet drill bit for radial and horizontal wells - Google Patents

Abstract

The invention relates to a self-propelled jet drill bit for radial and horizontal wells, which mainly includes a drill bit, a rotating shaft, a casing, a turbine stator, a turbine rotor, a rear nipple, a centralizer and a rear connection pipe, and a turbine system is installed inside the casing , the shell is placed between the drill bit and the centralizer, the front part is connected to the drill bit through the rotating shaft, the rear part is connected to the centralizer through the rear connecting pipe, the turbine rotor is fastened on the rotating shaft through the rotor nut and the flat key, and the rear part of the rotating shaft is passed through The sliding bearing sleeve is connected with the short joint at the rear, and the centralizer is connected with the empty sleeve of the rear joint. The turbine system transmits torque to the rotating shaft through the flat key, and the rotating shaft drives the drill bit to rotate, forming a rotary jet drilling of the drill bit, improving the rock breaking ability and drilling efficiency, and the rotating drill bit plays the role of modifying the well wall; The ejection from the upper and rear nozzle holes generates self-propelling force, which pushes the jet drill bit forward; the centralizer plays the role of centralizing the rear nozzle, preventing reverse torque, and reducing the frictional resistance during the drilling process.

Description

A self-propelled jet drill bit for radial and horizontal wells

technical field

The invention relates to a self-propelled jet drill bit for radial and horizontal wells.

Background technique

As the development of my country's oil and gas fields enters the middle and later stages, the water content of oil and gas wells increases, the effectiveness of water injection operations becomes lower and lower, the difficulty of oil and gas production increases, and it becomes extremely difficult to stabilize the production of oil and gas wells; in undeveloped oil and gas, the working conditions There are a large number of complex oil and gas reservoirs, and oil and gas reserves that are difficult to exploit account for a large proportion. At present, radial horizontal well drilling technology is widely used in the above-mentioned old oil and gas fields and oil and gas fields that are difficult to develop. Radial horizontal well technology can effectively reduce the cost of oil field development, save construction resources, increase oil field production, and speed up oil field production. efficiency. With the use of radial horizontal well drilling technology, it is found that there are still many problems in the drilling process that need to be solved urgently. Among them, the problems that need to be solved in the jet drill bit are as follows: (1) The insufficient water pressure of the jet drill bit leads to low rock-breaking ability and the distribution of the nozzle holes of the drill bit leads to irregular rock-breaking shapes, resulting in the great friction resistance of the front well wall, which limits the self-advancement of the jet drill bit. ; (2) The spray holes in front of the jet drill bit need to be designed with a certain distribution rule to make the rock-breaking point uniform in order to improve the efficiency; (3) The self-progressive force provided by the spray holes behind the jet drill bit is insufficient, which makes it difficult for the drill bit to overcome the borehole when drilling too deep. The frictional resistance drills forward, and the size of the self-progressive force of the drill limits the working depth of the drill.

Contents of the invention

The purpose of the invention is to improve a series of problems such as insufficient rock-breaking ability, insufficient self-propelling force and irregular shape of the well wall of the traditional jet drill bit. A self-propelled jet drill bit for radial and horizontal wells is proposed.

The technical scheme adopted in the present invention is:

The present invention is a self-propelled jet drill bit for radial and horizontal wells, which mainly includes a drill bit, a drill tooth, a rotating shaft, a shell, a turbine stator, a turbine rotor, a rear nipple, a centralizer and a rear connection pipe, and is characterized in that: The casing is equipped with a turbine system, the casing is placed between the drill bit and the centralizer, the front part is connected to the drill bit through the rotating shaft, the rear part is connected to the centralizer through the rear connection pipe, and the turbine rotor is fastened by the rotor nut and two long keys On the rotating shaft, the rear part of the rotating shaft is connected with the rear short joint through the sliding bearing sleeve, the centralizer is connected with the rear joint, the front is positioned by the circlip, and the rear is positioned by the rear connection boss.

The drill bit is protruding, and the front cascade and drill teeth are cancelled. The distribution of the drill teeth on each cascade is different, and a threaded hole is designed in each of the three cascade directions to fasten with the rotating shaft. The front end of the drill bit is designed There is a central nozzle and three oblique nozzles.

Four groups of turbine stators and turbine rotors are installed inside the housing, and the turbine stators and turbine rotors are all divided into sixteen blades in the circumferential direction; the housing and the rear connecting pipe are connected by nuts. The casing and the spacer ring have the same flow channel, and the front and rear ends of the casing are respectively equipped with a front end cover and a rear end cover.

A central hole and a deep hole are opened in the center of the rear short joint, and eight through holes are evenly distributed around the center of the rear short joint. One-third of the drilling fluid enters the rotating shaft through the center hole of the rear sub-section and is transmitted to the front drill bit, and two-thirds of the drilling fluid enters the turbine stator and rotor part through the eight peripheral holes of the rear sub-section.

The centralizer includes a centralizing block and two supporting blocks, and the centralizing block and the supporting blocks have the same flow channel. The righting block and the supporting block are connected by screws, and the two supporting blocks are connected by a spring.

Advantages of the present invention: (1) Rotate jet drilling of drill bit spray hole by means of turbine drive, increase rotational shearing force on rock, and improve drilling efficiency. (2) By setting sidetracking teeth, the rotating drill bit modifies the well wall to improve the stability of the well wall. (3) The front and rear injection holes are separated, the drill bit is equipped with the front injection hole, and the casing is equipped with the rear injection hole. The drilling fluid flows through the turbine and is discharged through the rear injection hole, fully utilizing the fluid kinetic energy. (4) The design of the centralizer can straighten the rear nozzle to reduce the frictional resistance during the drilling process. At the same time, the centralizer can also offset the reaction torque brought by the turbine drive, preventing the rear nozzle from rotating under the action of the reaction torque. (5) The protruding design of the drill bit can reduce the distance between the injection hole and the rock and improve the rock breaking effect.

Description of drawings

Fig. 1 is a structural schematic diagram of a self-propelled jet drill bit for radial and horizontal wells according to the present invention.

Fig. 2 is a view along the direction A of Fig. 1 .

Figure 3 is a cross-sectional view along the B-B direction of Figure 2

Fig. 4 is a schematic diagram of the rotation axis of the self-advancing jet drill bit for radial and horizontal wells.

Fig. 5 is a sectional view along line C-C of Fig. 4 .

Fig. 6 is a D-D sectional view of Fig. 1

Fig. 7 is a schematic diagram of the rear sub-section of the self-advancing jet drill bit for radial and horizontal wells.

Fig. 8 is a schematic diagram of the installation of the turbine stator and rotor of the self-propelled jet drill bit for radial and horizontal wells.

In the figure: 1. Rear connecting pipe, 2. Support block, 3. Centralizer, 4. Centralizing block, 5. Rear short joint, 6. Turbine stator, 7. Turbine rotor, 8. Flat key, 9. Spacer ring, 10. Front sliding bearing sleeve, 11. Drill bit, 12. Drill tooth, 13. High pressure hose joint, 14. Spring, 15. Circlip, 16. Rear end cover, 17. Housing, 18. Small diameter sliding bearing sleeve, 19. large-diameter sliding bearing sleeve, 20. rear spray hole, 21. front end cover, 22. rotating shaft, 23. front spray hole.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings.

Referring to accompanying drawings 1 to 8, a self-propelled jet drill bit for radial and horizontal wells provided in this embodiment mainly includes a drill bit 11, a drill tooth 12, a rotating shaft 22, a housing 17, a turbine stator 6, The turbine rotor 7, the rear short joint 5, the centralizer 3 and the rear connection pipe 1 are characterized in that: the casing 17 is equipped with a turbine system inside, the casing 17 is placed between the drill bit 11 and the centralizer 3, and the front part is rotated by The shaft 22 is connected with the drill bit 11, the rear part is connected with the centralizer 3 through the rear connecting pipe 1, the turbine rotor 7 is fastened on the rotating shaft 22 through the rotor nut and two flat keys 8, and the rear part of the rotating shaft 22 is connected with the sliding bearing sleeve 18. The rear pup joint 5 is connected, the centralizer 3 is empty with the rear connecting pipe 1, the front is positioned with the circlip 15, and the rear is positioned with the boss of the rear connecting pipe 1.

The drill bit 11 is a protruding type, and the front cascade and drill teeth are eliminated. The distribution of the drill teeth 12 on each cascade is different, and a threaded hole is designed in each of the three cascade directions to fasten with the rotating shaft 22. The front end of the drill bit is designed with a central spray hole 23 and three oblique spray holes 23 .

Four sets of turbine stators 6 and turbine rotors 7 are housed inside the housing 17, and the turbine stators 6 and turbine rotors 7 are all divided into sixteen blades in the circumferential direction; the housing 17 is connected to the rear connecting pipe 1 through nuts. The casing 17 and the spacer ring 9 have the same flow channel, and the front and rear ends of the casing 17 are respectively equipped with a front end cover 21 and a rear end cover 16 .

The center of the rear short joint 5 has a center hole and a deep hole in the center, and eight through holes are evenly distributed around the center of the rear short joint 5 . One-third of the drilling fluid enters the rotating shaft 22 through the center hole of the rear sub-section 5 and is transmitted to the front drill bit 11 and flows out from the front spray hole 23, and two-thirds of the drilling fluid passes through the eight surrounding holes of the rear sub-section 5 The part that enters the turbine stator and rotor is transmitted to the front end of the casing 17 and flows out through the rear spray hole 20 .

The centralizer 3 includes a centralizing block 4 and two supporting blocks 2, and the centralizing block 4 and the supporting blocks 3 have the same flow channel. The righting block 4 is connected with the support block 2 by screws, and the two support blocks are connected by a spring 14 .

The structure of the present invention is further described in conjunction with the working principle:

During radial and horizontal well operations, high-pressure drilling fluid enters the casing 17 through the rear joint 1, and diverts at the rear sub-section 5. One-third of the drilling fluid enters the rotating shaft 22 through the center hole of the rear sub-joint 5. The drilling fluid flows out from the front spray hole 23 of the drill bit 11; the remaining drilling fluid enters the turbine system through the eight holes equally divided around the rear nipple 5 to drive the turbine rotor 7 to rotate, and the turbine rotor 7 transmits the torque to the rotary shaft through the flat key 8 The shaft 22 drives the drill bit 11 to rotate, thereby forming a rotating jet flow and improving rock breaking efficiency; at the same time, the rotating drill bit 11 plays a role in modifying the well wall to improve the stability of the well wall. The drilling fluid entering the turbine system shoots to the well wall through the spacer ring 9 and the rear injection holes 20 at the front end of the housing 17 to generate self-propelled force. Push the jet drill bit forward under the action of force. The centralizer 3 can straighten the rear nozzle 1 to reduce the frictional resistance during the drilling process. At the same time, the centralizer 3 can also counteract the counter torque brought by the turbine drive to prevent the rear connector 1 from rotating under the action of the counter torque. The drilling fluid flowing from the drill bit and the drilling fluid ejected from the shell back flow through the flow channel of the centralizer 3 and finally circulate along the wellbore to the surface.

The terminology used herein in the description of the application is only for the purpose of describing specific embodiments, and is not intended to limit the application.

Claims (5)

1. A self-propelled jet drill bit for radial and horizontal wells, mainly comprising a drill bit (11), a drill tooth (12), a rotating shaft (22), a housing (17), a turbine stator (6), a turbine rotor (7 ), the rear pup joint (5), the centralizer (3) and the rear connection pipe (1), it is characterized in that: the casing (17) is equipped with a turbine system inside, and the casing (17) is placed on the drill bit (11) In the middle of the centralizer (3), the front part is connected with the drill bit (11) through the rotating shaft (22), the rear part is connected with the centralizer (3) through the rear connection pipe (1), and the turbine rotor (7) is connected through the rotor nut and two The flat key (8) is fastened on the rotating shaft (22), the rear part of the rotating shaft (22) is connected with the rear nipple (5) through the sliding bearing sleeve (18), the centralizer (3) is connected with the rear joint (1) Empty sleeve, the front is positioned with snap ring (15), and the rear is positioned with the boss of rear connecting pipe (1). 2. The self-propelled jet drill bit for a radial horizontal well according to claim 1, characterized in that: the drill bit (11) is a protruding type, canceling the front cascade and drill teeth, each cascade The drill teeth (12) are distributed differently, and a threaded hole is designed in each of the three cascade directions to fasten with the rotating shaft (22). The front end of the drill bit is designed with a central spray hole (23) and three oblique spray holes. (twenty three). 3. A self-propelled jet drill bit for radial and horizontal wells according to claim 1, characterized in that: four sets of turbine stators (6) and turbine rotors (7) are housed inside the housing (17), Both the turbine stator (6) and the turbine rotor (7) are divided into sixteen blades in the circumferential direction; the housing (17) is connected to the rear connecting pipe (1) through nuts, and the housing (17) and the spacer ring (9) have the same flow Road, the front end cover (21) and the rear end cover (16) are respectively equipped with at the front and rear ends of the housing (17). 4. A self-propelled jet drill bit for radial and horizontal wells according to claim 1, characterized in that: said rear subsection (5) has a center hole in the center and a deep hole in the center , eight through holes are evenly distributed around the center of the rear sub-section (5), and one-third of the drilling fluid enters the rotating shaft (22) through the center hole of the rear sub-section (5) and is transmitted to the front drill bit (11). The nozzle hole (23) flows out, and two-thirds of the drilling fluid enters the turbine stator and rotor part through the eight surrounding holes of the rear nipple (5), and is transmitted to the front end of the casing (17) to flow out from the rear nozzle hole (20). 5. A self-propelled jet drill bit for radial and horizontal wells according to claim 1, characterized in that: the centralizer (3) comprises a centralizing block (4) and two supporting blocks (2), and The righting block (4) and the supporting block (3) have the same flow channel, the righting block (4) and the supporting block (2) are connected by screws, and the two supporting blocks are connected by a spring (14).