Multi-stage variable-diameter punching drill bit

Abstract

The utility model discloses a multi-stage variable diameter punching drill bit which comprises a reamer body, the two ends of the reamer body are connected with an upper connector and a lower connector respectively, a core shaft is arranged in an inner cavity of the reamer body, the reamer body is connected with the core shaft through a shear pin, a blade fixing bottom plate is arranged on the surface of the core shaft, and the blade fixing bottom plate is connected with the upper connector and the lower connector. A blade is installed in the middle of the surface of the blade fixing bottom plate through two blade baffles, and a ball throwing seat is arranged in an inner cavity of the end, away from the upper connector, of the mandrel. A hydraulic mode is adopted in the starting mode, the pin is cut off by increasing the flow of the slurry pump, the mandrel drives the blade fixing bottom plate to move so that the reaming blade can stretch out, the reaming device can expand various borehole sizes during one-time tripping through the multi-stage variable-diameter structure, and by the arrangement of the ball throwing and jam releasing structure, the size of the reaming blade can be greatly reduced, and the service life of the reaming blade can be prolonged. And when the reaming cutter wings are clamped, clamping is released in a ball throwing and pressure building mode, and underground accidents caused by clamping are prevented.

Description

Technical Field

[0001] The utility model belongs to the technical field of drilling bits, and in particular relates to a multi-stage variable-diameter drilling bit. Background Art

[0002] Hole expansion while drilling is to expand the borehole size by using the hole expansion tool while the perforating drill is drilling. Hole expansion while drilling technology is mainly used to solve a series of problems such as borehole necking and wellbore collapse. Nowadays, hole expansion while drilling technology is constantly developing as an important means to deal with abnormal drilling conditions. As an advanced technology, hole expansion while drilling technology can solve the necking problem when drilling in plastic formations, improve cementing quality, and save tripping time to reduce drilling costs.

[0003] Currently available drilling drills cannot achieve the function of multi-stage variable diameter, and multiple drills need to be used for drilling in batches, which greatly reduces the drilling efficiency and has poor practicality. Utility Model Content

[0004] The utility model aims to provide a multi-stage variable diameter drilling drill to solve the technical problems raised in the background technology.

[0005] To achieve the above-mentioned purpose, the specific technical scheme of the utility model is as follows: a multi-stage variable diameter drilling drill bit comprises an reamer body, the two ends of the reamer body are respectively connected with an upper joint and a lower joint, the inner cavity of the reamer body is provided with a core shaft, and the reamer body is connected to the core shaft through a shear pin, the surface of the core shaft is provided with a blade fixing base plate, the middle part of the surface of the blade fixing base plate is provided with a blade through two blade baffles, the inner cavity of the core shaft away from the upper joint end is provided with a ball pitching seat, the core shaft is provided with a sleeve on the outer side of one end of the ball pitching seat, the core shaft is provided with a corrosion-resistant nozzle at one end of the sleeve, and a spring is provided on the core shaft, one end of the spring is connected to the sleeve through a spring lower baffle, and the other end is connected to a stroke control wheel through a spring upper baffle, and the stroke control wheel is connected to the core shaft through a thrust ball bearing.

[0006] Preferably, a side wall of one end of the core shaft located at the upper joint is provided with a shoulder, and the side wall of the shoulder contacts the end of the blade fixing base plate.

[0007] Preferably, the core shaft is connected to the corrosion-resistant nozzle via threads.

[0008] Preferably, the reamer body is connected to the upper joint and the lower joint through threads, and pressure balancing holes are provided at both upper and lower ends of the reamer body.

[0009] Preferably, a fixing pin hole is provided on the reamer body, and the stroke control wheel is connected to the fixing pin hole via a stroke control wheel fixing pin.

[0010] Preferably, the surface of the reamer body is provided with guide grooves distributed corresponding to the blades.

[0011] Preferably, an O-ring is provided at the connection between the lower joint and the reamer body.

[0012] The utility model has the following advantages:

[0013] The utility model adopts a hydraulic starting method, by increasing the flow of the mud pump to cut the pin, the core shaft drives the movement of the blade fixing bottom plate to extend the reaming blade, and by providing a multi-stage variable diameter structure, the reamer can complete the expansion of various wellbore sizes during one trip, thereby greatly improving the drilling efficiency. By providing a ball-throwing unblocking structure, when the reaming blade is stuck, the ball is thrown to hold the pressure to release the jam, thereby preventing underground accidents caused by jamming. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solution of the implementation mode of the utility model, the drawings required for use in the implementation mode will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0016] Figure 2 This is a schematic diagram of the structure of the central shaft of the utility model;

[0017] Figure 3 This is a schematic diagram of the structure of the blade fixing base plate in the utility model;

[0018] Figure 4 It is a structural schematic diagram of the reamer body in the utility model.

[0019] Explanation of the markings in the figure: 1. Upper joint; 2. Pressure balance hole; 3. Blade baffle; 4. Blade; 5. Shear pin; 6. Stroke control wheel fixing pin; 7. Spring; 8. Spring lower baffle; 9. Eye reamer body; 10. Corrosion-resistant nozzle; 11. Lower joint; 12. O-ring; 13. Sleeve; 14. Ball pitching seat; 15. Spring upper baffle; 16. Stroke control wheel; 17. Thrust ball bearing; 18. Fixing pin; 19. Blade fixing base plate; 20. Mandrel; 21. Shoulder; 22. Guide groove. DETAILED DESCRIPTION

[0020] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the embodiments of the present invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0021] In the description of the embodiments of the present invention, it should be understood that the terms "length", "vertical", "horizontal", "top", "bottom", etc. indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present invention.

[0022] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present utility model, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0023] In the embodiments of the present utility model, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.

[0024] The disclosure below provides many different embodiments or examples for realizing different structures of the embodiments of the present utility model. In order to simplify the disclosure of the embodiments of the present utility model, the components and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the embodiments of the present utility model. In addition, the embodiments of the present utility model can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed.

[0025] In order to better understand the purpose, structure and function of the utility model, the following is a further detailed description of a multi-stage variable diameter drilling drill bit of the utility model in conjunction with the accompanying drawings.

[0026] like Figure 1-4As shown, a multi-stage variable diameter drilling drill bit of the utility model comprises an reamer body 9, both ends of which are respectively connected with an upper joint 1 and a lower joint 11, an inner cavity of the reamer body 9 is provided with a core shaft 20, and the reamer body 9 is connected to the core shaft 20 through a shear pin 5, a blade fixing base plate 19 is provided on the surface of the core shaft 20, a blade wing fixing base plate 19 is installed with a blade wing 4 through two blade wing baffles 3 in the middle part of the surface of the blade wing fixing base plate 19, the blade wing fixing base plate 19 and the blade wing baffle 3 are connected by fixing screws 18, the function of the blade wing baffle 3 is to provide an axial support force for the blade wing 4, and the blade wing fixing base plate 19 can drive the blade wing 4 to move axially under the action of the core shaft 20. The circumferential fixation of the blade 4 utilizes the reamer body 9. The blade 4 and the reamer body 9 are connected by a guide groove, which ensures that the blade 4 moves along a fixed track without sliding out of the reamer body 9. A ball-casting seat 14 is provided in the inner cavity of the end of the mandrel 20 away from the upper joint 1. A sleeve 13 is sleeved on the outer side of the ball-casting seat 14 at one end of the mandrel 20. A corrosion-resistant nozzle 10 is provided at one end of the mandrel 20 located at the sleeve 13, and a spring 7 is sleeved on the mandrel 20. One end of the spring 7 is connected to the sleeve 13 through a spring lower baffle 8, and the other end is connected to a stroke control wheel 16 through a spring upper baffle 15. The stroke control wheel 16 is connected to the mandrel 20 through a thrust ball bearing 17.

[0027] The mandrel 20 is located at one end of the upper joint 1 and is provided with a boss 21 on the side wall. The side wall of the boss 21 contacts the end of the blade fixing base plate 19. The mandrel 20 is connected to the corrosion-resistant nozzle 10 by a thread. The boss 21 is used to push the movement of the blade fixing base plate 19. When the drilling fluid moves at a certain flow rate, the force acting on the nozzle wall is the fundamental reason for the movement of the reamer blade. When the drilling fluid flow rate remains unchanged, the force on the mandrel 20 can be changed by replacing the diameter size of the corrosion-resistant nozzle 10. Another function of the corrosion-resistant nozzle 10 is to provide a support for the sliding of the pitching seat 14 after pitching. The lower end of the mandrel 20 is disconnected and has an interference fit with the pitching seat 14. When the mandrel and the pitching seat 14 are in a suitable interference fit, it can ensure that the drilling fluid will not flush the pitching seat 14 away from the joint under normal flow, and can also ensure that the pitching seat 14 can slide smoothly to the corrosion-resistant nozzle 10 after pitching. The reamer body 9 is connected to the upper joint 1 and the lower joint 11 by threads, and the upper and lower ends of the reamer body 9 are provided with pressure balance holes 2. The pressure balance holes 2 are provided to avoid the formation of a vacuum or a closed space inside the reamer. The diameter of the lower section of the reamer is smaller than that of the upper section, in order to provide support for the lower spring baffle 8. The reamer body 9 is provided with a fixing pin hole, and the stroke control wheel 16 is connected to the fixing pin hole through the stroke control wheel fixing pin 6. The surface of the reamer body 9 is provided with a guide groove 22 corresponding to the blade wing 4, so that the blade wing 4 extends out. The connection between the lower joint 11 and the reamer body 9 is provided with an O-ring 12, which has a good sealing effect.

[0028] The working principle of the multi-stage variable diameter perforating drill bit is as follows: when the drill bit is drilling normally, the reamer plays the role of transmitting drilling pressure and torque as a part of the drill string short section. At this time, when the drilling fluid moves in the reamer at a normal flow rate, due to the fixing effect of the shear pin 5 and the design of the size of the mandrel 20, the drilling fluid force on the mandrel 20 is not enough to shear off the shear pin 5 to push the blade fixing base plate 19 to move and extend the reaming blade 4. When the reamer is in the reaming section, when the drilling fluid flow Q is increased to a certain value, the mandrel 20 shears off the shear pin 5 under the action of the pressure difference, and then pushes the blade fixing base plate 19 to move so that the blade 4 extends along the guide groove 22 on the reamer body. When the pump is stopped, the squeezed spring 7 pushes the stroke control wheel 16 to reset the reaming blade 4.

[0029] Principle of multi-stage diameter reduction of drilling reamer: The multi-stage diameter reduction of drilling reamer is mainly achieved by multi-stage diameter reduction mechanism, which is composed of thrust ball bearing 17, stroke control wheel 16, stroke control wheel fixing pin 6, spring upper baffle 15, spring lower baffle, spring 7. When the reamer is started, the mandrel 20 pushes the blade fixing base plate 19 to move, and the blade fixing base plate 19 squeezes the stroke control wheel 16 at the same time. Due to the action of the stroke control wheel fixing pin 6, the stroke control wheel 16 can only rotate and move axially along the slideway above it. By defining the length of the slideway on the stroke control wheel 16, the extension size of each stage of the blade 4 can be defined.

[0030] The principle of unblocking the under-drilling reamer is as follows: when the blade 4 is stuck, a steel ball is pumped into the drill string, and the steel ball moves with the drilling fluid to the ball-dropping seat 14 to hold the pressure, and then the ball-dropping seat 14 is separated from the core shaft 20 under the action of pressure, and the drilling fluid squeezes the spring lower baffle 8 so that the stuck blade 4 is reset under the action of the liquid pressure.

[0031] It is understood that the present invention is described by some embodiments, and those skilled in the art are aware that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. A multi-stage variable diameter drilling drill, characterized in that: The invention comprises an reamer body (9), wherein the two ends of the reamer body (9) are respectively connected to an upper joint (1) and a lower joint (11), the inner cavity of the reamer body (9) is provided with a core shaft (20), and the reamer body (9) is connected to the core shaft (20) via a shear pin (5), the surface of the core shaft (20) is provided with a blade fixing base plate (19), a blade (4) is installed at the middle part of the surface of the blade fixing base plate (19) via two blade baffles (3), and the inner cavity of the core shaft (20) at one end away from the upper joint (1) is provided with a blade fixing base plate (19). A ball pitching seat (14) is provided, a sleeve (13) is sleeved on the outer side of the core shaft (20) located at one end of the ball pitching seat (14), a corrosion-resistant nozzle (10) is provided on the core shaft (20) located at one end of the sleeve (13), and a spring (7) is sleeved on the core shaft (20), one end of the spring (7) is connected to the sleeve (13) through a spring lower baffle (8), and the other end is connected to a stroke control wheel (16) through a spring upper baffle (15), and the stroke control wheel (16) is connected to the core shaft (20) through a thrust ball bearing (17).

2. A multi-stage variable diameter drilling drill according to claim 1, characterized in that: A convex shoulder (21) is provided on a side wall of one end of the core shaft (20) located at the upper joint (1), and a side wall of the convex shoulder (21) contacts an end of a blade fixing base plate (19).

3. The multi-stage variable diameter drilling drill according to claim 1, characterized in that: The core shaft (20) and the corrosion-resistant nozzle (10) are connected via threads.

4. The multi-stage variable diameter drilling drill according to claim 1, characterized in that: The reamer body (9) is connected to the upper joint (1) and the lower joint (11) via threads, and pressure balance holes (2) are provided at both upper and lower ends of the reamer body (9).

5. The multi-stage variable diameter drilling drill according to claim 1, characterized in that: The reamer body (9) is provided with a fixing pin hole, and the stroke control wheel (16) is connected to the fixing pin hole via the stroke control wheel fixing pin (6).

6. The multi-stage variable diameter drilling drill according to claim 1, characterized in that: The surface of the reamer body (9) is provided with guide grooves (22) distributed corresponding to the blade wings (4).

7. The multi-stage variable diameter drilling drill according to claim 1, characterized in that: An O-ring (12) is provided at the connection between the lower joint (11) and the reamer body (9).

Images