CN109931000B

CN109931000B - Adjustable jet oscillation PDC drill bit

Info

Publication number: CN109931000B
Application number: CN201910328668.1A
Authority: CN
Inventors: 田家林; 杨应林; 宋豪林; 梁蓝月; 文峰; 刘刚; 邓喆
Original assignee: Southwest Petroleum University
Current assignee: Sichuan Bao Wright drill Co.,Ltd.
Priority date: 2019-04-23
Filing date: 2019-04-23
Publication date: 2020-07-24
Anticipated expiration: 2039-04-23
Also published as: CN109931000A

Abstract

The invention discloses an adjustable jet oscillation PDC drill bit which mainly comprises a fixed joint, a drill bit body, a rectangular sealing ring, a pre-pressing spring, an opening piston, a jet short section and a positioning pin. Drilling fluid enters the adjustable jet oscillation PDC drill bit from the fixed joint, enters the bottom of the drill bit through the opening of the central flow channel of the piston and flows out of a water hole of the drill bit, when the pressure of the drilling fluid is increased, the pre-pressing spring is compressed, the opening piston descends, the opening piston is communicated with a round hole of the jet nipple, the drilling fluid enters the jet nipple to generate a jet oscillation effect and acts on the drill bit; when drilling fluid pressure reduces, the pre-compaction spring resets, and the piston rebound gets back to initial position, opens the round hole nonconnection of piston and efflux nipple joint, and the PDC drill bit does not possess efflux oscillation function, realizes efflux oscillation control through adjusting drilling fluid pressure. The adjustable jet oscillation PDC drill bit can realize the adjustment and control of the jet oscillation function, and the rock breaking efficiency of the drill bit is improved by adjusting the pressure of drilling fluid.

Description

Adjustable jet oscillation PDC drill bit

Technical Field

The invention relates to an adjustable jet oscillation PDC drill bit for petroleum and natural gas exploration and development, which is also suitable for the technical equipment fields of mining, geological drilling, constructional engineering, tunnel engineering, non-excavation and the like.

Background

At present, with the continuous exploration and development of conventional petroleum and natural gas resources, the development of oil and gas resources gradually develops into the fields of deep wells and ultra-deep wells, and with the increase of drilling depth, the strength and hardness of rocks are obviously increased under the action of formation confining pressure, so that the extreme value of the drillability of the rocks is higher, the mechanical drilling speed is slowed down, the drilling time is prolonged, and the drilling cost is increased. The PDC drill bit has the advantages that the service life and the rock breaking efficiency of the PDC drill bit under the novel oil-gas resource condition are newly required, the PDC drill bit is frequently deviated from the center position of a well hole and is shaken left and right due to the fact that the PDC drill bit is interfered by external factors when the PDC drill bit works normally, the rock breaking efficiency of the periphery of the outline of the PDC drill bit is high, relatively few PDC cutting teeth are often arranged at the center of the outline of the PDC drill bit, and the rock breaking efficiency of the center of the PDC drill bit is.

In order to improve the rock breaking efficiency of the PDC drill bit, improve the mechanical drilling speed and reduce the drilling cost, the new structural design of the PDC drill bit is an urgent need of oil-gas well drilling engineering. Conventional PDC drill bit designs typically optimize the structure of the PDC drill bit by optimizing a tooth arrangement scheme, improving the structural design of the bit body, changing the size of the PDC cutters, and the like, so as to meet new requirements for service performance. But along with the exploration and development of novel oil gas resources, higher requirement is proposed to the PDC drill bit, consequently breaks through current drill bit structural design scheme and is the inevitable selection that improves drill bit performance, especially through the structural component who increases the drill bit to satisfy the functional requirement of PDC drill bit.

Disclosure of Invention

In order to explore and solve the problems of improving the rock breaking efficiency of the PDC drill bit, improving the mechanical drilling speed and reducing the drilling cost in the background technology, the invention provides the adjustable jet oscillation PDC drill bit. When the adjustable jet oscillation PDC drill bit works, drilling fluid enters the fixed joint, then enters the bottom of the drill bit through the opening of the piston central flow channel and flows out of a drill bit water hole, when the pressure of the drilling fluid is increased, the pre-pressing spring is further compressed under the action of the pressure of the drilling fluid, the opening piston moves downwards, the opening piston is communicated with a round hole of the jet nipple, the drilling fluid enters the jet nipple, and is circularly switched in the jet nipple to generate a jet oscillation effect to act on the drill bit, so that the rock breaking efficiency of the drill bit is improved; when drilling fluid pressure reduces, the pre-compaction spring resets, and the piston rebound gets back to initial position, opens the round hole nonconnection of piston and efflux nipple joint, does not have fluid circulation in the efflux nipple joint, and the PDC drill bit does not possess efflux oscillation function, realizes the efflux oscillation control of PDC drill bit through adjusting drilling fluid pressure.

The technical scheme of the invention is as follows: the adjustable jet oscillation PDC drill bit mainly comprises a fixed joint, a drill bit body, a rectangular sealing ring, a pre-pressing spring, an opening piston, a jet short section and a positioning pin, the rectangular sealing ring, the prepressing spring, the opening piston, the jet pipe nipple and the positioning pin are positioned in the drill bit body, the positioning pin is firstly installed on the inner circumference of the drill bit body, then the jet pipe nipple is installed, the jet flow short section is ensured not to generate circumferential rotation through the positioning of the positioning pin, then the pre-pressing spring is arranged on the opening piston, a rectangular sealing ring is arranged on the outer circumference of the rear end of the opening piston, the opening piston is arranged on the jet flow short section, and the prepressing spring is kept under certain prepressing force, then carry out axial positioning through fixed joint to inside rectangle sealing washer, pre-compaction spring of drill bit body, open piston, efflux nipple joint, locating pin, open the through-hole that has the intercommunication on the circumference of piston and efflux nipple joint.

The fixed joint is connected with the drill bit body through threads, after the thread matching is completed, the fixed joint is completely and fixedly connected with the drill bit body through a welding mode, the welding line on the outer circumference of the fixed joint and the drill bit body is polished, and the surface roughness of the welding line position is guaranteed.

The positioning pins are uniformly distributed on the inner circumference of the drill bit body in an angle of 90 degrees.

Open and adopt spline fit between piston and the efflux nipple joint, be provided with 4 external splines that are 90 equipartitions on opening the piston outer circumference, be provided with 4 internal spline grooves that are 90 equipartitions in the internal circumference of efflux nipple joint, through spline fit, guarantee to open and do not produce relative rotation between piston and the efflux nipple joint, and open the piston and can efflux nipple joint axial displacement relatively, when drilling fluid pressure increases, the effort that is opening piston rear end terminal surface increases, open the piston downstream, the pre-compaction spring is further compressed, when opening the through-hole intercommunication on piston and the efflux nipple joint circumference, drilling fluid gets into the circulation runner on the efflux nipple joint circumference.

The number of the circulating flow channels is 4 groups, and the circulating flow channels are uniformly distributed on the outer circumference of the jet nipple at 90 degrees.

The invention has the beneficial effects that: (1) the control of the jet oscillation function of the PDC drill bit is realized by adjusting the pressure of the drilling fluid, the jet oscillation function of the drill bit can be turned on or off as required, and the application range of the PDC drill bit is enlarged; (2) when the piston is started to move downwards and the jet nipple works, the PDC drill bit has a jet oscillation function, so that a jet oscillation function is provided for the drill bit, and the rock breaking efficiency of the drill bit can be improved; (3) the opening piston is matched with the jet nipple by adopting a spline, so that the positioning is reliable, and the opening piston can be communicated with the round hole of the jet nipple; (4) the jet nipple and the drill bit body are positioned by the positioning pin, and the positioning mode is simple and reliable.

Drawings

Fig. 1 is a schematic structural view of the present invention.

Fig. 2 is a schematic diagram of the operation of the present invention.

Fig. 3 is a cross-sectional view a-a of fig. 2 of the present invention.

Fig. 4 is a cross-sectional view B-B of the invention of fig. 2.

Figure 5 is a cross-sectional view of the invention taken along line C-C of figure 2.

Fig. 6 is a cross-sectional view D-D of the invention of fig. 2.

Fig. 7 is a schematic view of the structure of the opening piston.

FIG. 8 is a schematic diagram of a jet nipple.

In the figure, 1 is a fixed joint, 2 is a drill bit body, 3 is a rectangular sealing ring, 4 is a pre-pressing spring, 5 is an opening piston, 6 is a jet nipple, and 7 is a positioning pin.

Detailed Description

Exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It is to be understood that the embodiments shown and described in the drawings are merely exemplary and are intended to illustrate the principles and spirit of the invention, not to limit the scope of the invention.

It will be appreciated by those of ordinary skill in the art that the embodiments described herein are intended to assist the reader in understanding the principles of the invention and are to be construed as being without limitation to such specifically recited embodiments and examples. Those skilled in the art can make various other specific changes and combinations based on the teachings of the present invention without departing from the spirit of the invention, and these changes and combinations are within the scope of the invention.

Referring to the attached drawings, the adjustable jet oscillation PDC drill bit mainly comprises a fixed joint 1, a drill bit body 2, a rectangular sealing ring 3, a pre-pressing spring 4, an opening piston 5, a jet short section 6 and a positioning pin 7, wherein the rectangular sealing ring 3, the pre-pressing spring 4, the opening piston 5, the jet short section 6 and the positioning pin 7 are located inside the drill bit body 2, the positioning pin 7 is installed on the inner circumference of the drill bit body 2, the jet short section 6 is installed, the jet short section 6 is ensured not to generate circumferential rotation through the positioning of the positioning pin 7, the pre-pressing spring 4 is installed on the opening piston 5, the rectangular sealing ring 3 is installed on the outer circumference of the rear end of the opening piston 5, the opening piston 5 is installed on the jet short section 6, the pre-pressing spring 4 is kept under certain pre-pressing force, and the rectangular sealing ring 3, the pre-, The opening piston 5, the jet flow nipple 6 and the positioning pin 7 are axially positioned, and through holes which can be communicated are formed in the circumferences of the opening piston 5 and the jet flow nipple 6.

Fixed joint 1 and drill bit body 2 pass through threaded connection and be in the same place, accomplish the screw-thread fit back, through the welding mode, link firmly fixed joint 1 and drill bit body 2 together completely to the welding seam on fixed joint 1 and the outer circumference of drill bit body 2 is polished, guarantees the roughness at welding seam position.

Open and adopt spline fit between piston 5 and the efflux nipple joint 6, be provided with 4 external splines that are 90 equipartitions on opening piston 5 outer circumference, be provided with 4 internal spline grooves that are 90 equipartitions in the circumference in efflux nipple joint 6, through spline fit, guarantee to open and do not produce relative rotation between piston 5 and the efflux nipple joint 6, and open piston 5 and can be relative efflux nipple joint 6 axial displacement, when drilling fluid pressure increases, the effort that is used in opening 5 rear end terminal surface of piston increases, open piston 5 downstream, pre-compaction spring 4 is further compressed, when opening piston 5 and the through-hole intercommunication on the efflux nipple joint 6 circumference, drilling fluid gets into the circulation flow channel on the efflux nipple joint 6 circumference.

The positioning pins 7 are uniformly distributed on the inner circumference of the drill bit body 2 in an angle of 90 degrees; the number of the circulating flow channels is 4 groups, and the circulating flow channels are uniformly distributed on the outer circumference of the jet nipple 6 at 90 degrees.

Claims

1. The jet oscillation PDC drill bit that can regulate and control, its characterized in that: the adjustable jet oscillation PDC drill bit mainly comprises a fixed joint (1), a drill bit body (2), a rectangular sealing ring (3), a pre-pressing spring (4), an opening piston (5), a jet short section (6) and a positioning pin (7), wherein the rectangular sealing ring (3), the pre-pressing spring (4), the opening piston (5), the jet short section (6) and the positioning pin (7) are positioned inside the drill bit body (2), the positioning pin (7) is firstly installed on the inner circumference of the drill bit body (2), then the jet short section (6) is installed, the jet short section (6) is ensured not to generate circumferential rotation through the positioning of the positioning pin (7), then the pre-pressing spring (4) is installed on the opening piston (5), the rectangular sealing ring (3) is installed on the outer circumference of the rear end of the opening piston (5), and then the opening piston (5) is installed on the jet short section (, and the prepressing spring (4) is kept to bear certain prepressing force, then the rectangular sealing ring (3), the prepressing spring (4), the opening piston (5), the jet short section (6) and the positioning pin (7) in the drill bit body (2) are axially positioned through the fixed joint (1), and through holes which can be communicated are formed in the circumferences of the opening piston (5) and the jet short section (6).

2. The adjustable jet oscillating PDC drill bit of claim 1, wherein: fixed joint (1) and drill bit body (2) pass through threaded connection and be in the same place, accomplish the screw-thread fit back, link firmly fixed joint (1) and drill bit body (2) together completely through the welding mode to the welding seam on fixed joint (1) and drill bit body (2) outer circumference is polished, guarantees the roughness at welding seam position.

3. The adjustable jet oscillating PDC drill bit of claim 1, wherein: the positioning pins (7) are uniformly distributed on the inner circumference of the drill bit body (2) in an angle of 90 degrees.

4. The adjustable jet oscillating PDC drill bit of claim 1, wherein: open piston (5) and efflux nipple joint (6) between adopt spline fit, be provided with 4 external splines that are 90 equipartitions on opening piston (5) outer circumference, be provided with 4 internal spline grooves that are 90 equipartitions on the circumference in efflux nipple joint (6), through spline fit, guarantee not to produce relative rotation between opening piston (5) and efflux nipple joint (6), and open piston (5) can efflux nipple joint (6) axial displacement relatively, when drilling fluid pressure power increase, the effort increase of effect at opening piston (5) rear end terminal surface, open piston (5) downstream, pre-compaction spring (4) are further compressed, when opening piston (5) and efflux nipple joint (6) through-hole intercommunication on the circumference, drilling fluid gets into the circulation runner on efflux nipple joint (6) circumference.

5. The adjustable jet oscillating PDC drill bit of claim 4, wherein: the number of the circulating flow channels is 4, and the circulating flow channels are uniformly distributed on the outer circumference of the jet nipple (6) at 90 degrees.