Impact generator for generating high frequency and low amplitude energy

Abstract

The present invention provides an impact generator for generating high-frequency and low-amplitude energy, comprising a main shaft and a shell coaxially sleeved on the outside of the main shaft, a motor assembly is arranged in the shell, the motor assembly is connected to the top of the main shaft, and the main shaft is driven to rotate under the action of drilling fluid; an impact part cavity is formed between the inner wall of the shell and the outer wall of the main shaft, an elastic telescopic member and an impact part are arranged in the impact part cavity, the top of the elastic telescopic member is fixed, and the bottom is connected to the top of the impact part, a positioning member is arranged on the impact part, and a ratchet groove matching the positioning member is opened on the outer wall of the main shaft, the ratchet groove is Z-shaped, and when the positioning member is located at the lowest point of the ratchet groove, the bottom of the shell is respectively in contact with the impact part and the main shaft. The benefit of the present invention is that by arranging the ratchet groove on the main shaft, cooperating with the impact part, the elastic telescopic member and adjusting the displacement of the drilling fluid, the demand for applying high-frequency and low-amplitude impact energy to the drill bit can be met.

Description

Technical Field

[0001] The invention relates to an impact generator, in particular to an impact generator for generating high-frequency and low-amplitude energy. Background Art

[0002] In the technical fields of oil and gas drilling, geological exploration, and mining drilling, as the depth of the well continues to increase, the rock becomes harder and harder, which seriously restricts the rock breaking efficiency of the drill bit. Existing theoretical research and field practice show that applying a certain frequency of impact force on the drill bit during the rock breaking process of the drill bit can effectively improve the rock breaking efficiency of the drill bit. At present, conventional impact tools provide low-frequency and high-amplitude impact energy. Its rock breaking mechanism is to use a large amplitude impact force to produce large cracks on the rock surface, and then remove the rock cuttings from the bottom of the well under the action of the drill bit rotation. However, it is found in actual application that when the rock is harder and the impact force is greater, although the initial rock breaking efficiency of the drill bit is higher, the drilling efficiency is greatly reduced over time. The main reason is that the impact force causes the drill bit cutting teeth to break, which affects the later rock breaking efficiency. Foreign studies have shown that applying high-frequency, low-amplitude impact energy to the drill bit can not only greatly improve drilling efficiency, but also not easily damage the drill bit cutting teeth, which is beneficial to extending the service life of the drill bit. The mechanism is that although the impact energy of lower amplitude can only produce small microcracks on the rock surface, under the action of high-frequency impact, the microcrack expansion rate increases and connects to form larger cracks, and the drill bit can rotate and shear to quickly separate the rock cuttings from the bottom of the well. Therefore, it is urgent to design and develop an impact generator that can generate high-frequency, low-amplitude impact energy to assist in improving the rock breaking efficiency of the drill bit, and can control and adjust the impact parameters in real time, while meeting the technical requirements and equipment requirements of the existing drilling process, and has a simple structure, low cost, and easy maintenance. Summary of the invention

[0003] The object of the present invention is to provide an impact generator for generating high-frequency and low-amplitude energy to solve the above-mentioned problems.

[0004] The present invention provides an impact generator for generating high-frequency and low-amplitude energy, comprising a main shaft and a shell coaxially sleeved on the outside of the main shaft, wherein a motor assembly is arranged in the shell, and the motor assembly is connected to the top of the main shaft, and drives the main shaft to rotate under the action of drilling fluid; an impact part cavity is formed between the inner wall of the shell and the outer wall of the main shaft, and an elastic telescopic part and an impact part are arranged in the impact part cavity, the top of the elastic telescopic part is fixed, and the bottom is connected to the top of the impact part, a positioning part is arranged on the impact part, and a ratchet groove matched with the positioning part is opened on the outer wall of the main shaft, and the ratchet groove is Z-shaped, and when the positioning part is located at the lowest point of the ratchet groove, the bottom of the shell abuts against the impact part and the main shaft respectively.

[0005] Preferably, a bypass hole is opened at the top of the main shaft, and an axially penetrating drilling fluid channel hole is arranged inside, and the bypass hole is connected with the drilling fluid channel hole.

[0006] Preferably, the motor assembly comprises a rotor and a stator, the rotor is connected to the top of the main shaft via a coupling, and the stator is fixed to the inner wall of the housing.

[0007] Preferably, the shell includes an upper limit member and a lower limit member which are arranged on the inner wall and are in an annular shape, the top of the elastic telescopic member is fixed on the upper limit member, and when the positioning member is located at the lowest point of the ratchet groove, the bottom of the impact part abuts against the lower limit member.

[0008] Preferably, the ratchet groove comprises an inclined section and a vertical section which are sequentially connected end to end.

[0009] Preferably, a thrust bearing is provided between the bottom of the housing and the main shaft.

[0010] The benefit of the present invention lies in that by arranging a ratchet groove on the main shaft, cooperating with the impact part, the elastic telescopic part and the adjustment of the drilling fluid discharge volume, the demand for applying high-frequency and low-amplitude impact energy to the drill bit can be met. It has a simple structural design, reliable performance, convenient operation, low cost, and easy frequency adjustment, and can be widely promoted and used. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a cross-sectional view of an impact generator of the present invention;

[0012] Figure 2 It is a schematic diagram of the structure of the spine groove.

[0013] Component number description:

[0014] 1 Housing

[0015] 11 Upper limit piece

[0016] 12 Lower limiter

[0017] 2 Motor assembly

[0018] 21 Rotor

[0019] 22 Stator

[0020] 3 Coupling

[0021] 4 Spindle

[0022] 401 Axis 1

[0023] 402 Axis 2

[0024] 41 Bypass hole

[0025] 42 Thorn Groove

[0026] 421 inclined section

[0027] 422 vertical segment

[0028] 43 Drilling fluid channel hole

[0029] 5 Impact part

[0030] 51 Positioning piece

[0031] 6 Elastic expansion joints

[0032] 7 Thrust bearing DETAILED DESCRIPTION

[0033] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. These embodiments are only used to illustrate the present invention, but not to limit the present invention.

[0034] In the description of the present invention, it should be noted that the terms "upper", "lower", "top", "bottom", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] like Figure 1 As shown, the present invention provides an impact generator for generating high-frequency and low-amplitude energy, the impact generator comprising a main shaft 4 and a housing 1 coaxially sleeved on the outside of the main shaft 4. In a specific embodiment of the present invention, the main shaft 4 is stepped, comprising a shaft body 1 401 with a smaller outer diameter and a shaft body 2 402 with a larger outer diameter, and the housing 1 is sleeved on the outside of the shaft body 1 401.

[0037] A motor assembly 2 is provided in the housing 1. The motor assembly 2 specifically includes a rotor 21 and a stator 22. The rotor 21 is connected to the top of the shaft body 401 through a coupling 3, and the stator 22 is fixed on the inner wall of the housing 1. After the filtered drilling fluid flows into the motor assembly 2, it will cause a certain pressure difference in the motor assembly 2, pushing the rotor 21 to rotate around the axis of the stator 22, and then driving the main shaft 4 to rotate. In a specific implementation, a bypass hole 41 is also opened at the top of the shaft body 401, and an axially through drilling fluid channel hole 43 is provided inside the main shaft 4, and the bypass hole 41 is connected to the drilling fluid channel hole 43. In this way, most of the drilling fluid will flow into the drilling fluid channel hole 43 through the bypass hole 41 after pushing the rotor 21 to do work, and finally be sprayed out through the drill bit water hole, so as to realize the cooling and cleaning of the drill bit and the recycling of the drilling fluid.

[0038] In order to apply high-frequency and low-amplitude impact energy to the drill bit, an impact cavity is formed between the inner wall of the housing 1 and the outer wall of the shaft body 401. An elastic telescopic member 6 and an impact portion 5 are arranged in the impact cavity. The elastic telescopic member 6 is specifically a spring, the top of which is fixed, and the bottom is connected to the top of the impact portion 5. A positioning member 51 is arranged on the impact portion 5, and a ratchet groove 42 matching the positioning member 51 is opened on the outer wall of the shaft body 401. The ratchet groove 42 is as shown in FIG. Figure 2 It is Z-shaped as shown. When the positioning member 51 is located at the lowest point of the ratchet groove 42, the shell 1 abuts against the impact part 5 and the main shaft 4 respectively. In this way, when the main shaft 4 rotates, the positioning member 51 will reciprocate up and down along the ratchet groove 42, and convert the elastic potential energy stored in the elastic telescopic member 6 under pressure when the positioning member 51 moves upward into the impact force transmitted to the main shaft 4 through the shell 1 when the positioning member 51 moves downward. Preferably, the shell 1 includes an upper limit member 11 and a lower limit member 12 arranged on the inner wall and in an annular shape. The impact part cavity is jointly defined by the upper limit member 11, the outer wall of the shaft body 401, the lower limit member 12 and the inner wall of the shell 1. The upper end of the elastic telescopic member 6 is fixed on the upper limit member 11. When the positioning member 51 is located at the lowest point of the ratchet groove 42, the bottom of the impact part 5 abuts against the lower limit member 12. A thrust bearing 7 is also provided between the lower stopper 12 and the second shaft body 402, and the thrust bearing 7 is used to bear the axial impact force brought by the housing 1 and transmit the impact force to the main shaft 4. Further, the ratchet groove 42 includes an inclined section 421 and a vertical section 422 connected end to end in sequence, and the vertical section 422 extending vertically is provided to facilitate the rapid fall of the impact part 5, thereby achieving the impact effect. Those skilled in the art can adjust the shape, amplitude and other parameters of the ratchet groove 42 as needed to meet the requirements of applying high-frequency and low-amplitude impact energy to the drill bit.

[0039] The working principle of the impact generator of the present invention is as follows:

[0040] Under the action of the drilling fluid, the motor assembly 2 drives the main shaft 4 to rotate through the coupling 3. When the main shaft 4 rotates, due to the limiting effect of the ratchet groove 42, the positioning member 51 will move along the ratchet groove 42, driving the impact part 5 to move up and down reciprocatingly. When the impact part moves upward along the inclined section 421, the elastic telescopic member 6 is compressed to store elastic potential energy. Then, when the positioning member 51 enters the vertical section 422, the elastic telescopic member 6 drives the impact part 5 to move rapidly downward until it reaches the lowest point of the ratchet groove 42 under the action of elastic reset, impacting the lower limiting member 12 and the thrust bearing 7, and transmitting the impact force to the main shaft 4 through the thrust bearing 7, and finally to the drill bit, so as to achieve the effect of assisting the drill bit to break the rock. As the main shaft 4 continues to rotate, the above process is repeated continuously, thereby producing a cyclical impact effect on the drill bit. In this process, the operator can control the impact frequency of the impact generator by adjusting the displacement of the drilling fluid, so as to meet the technical and process requirements of different working conditions.

[0041] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. An impact generator for generating high-frequency and low-amplitude energy, characterized in that: It comprises a main shaft (4) and a housing (1) coaxially sleeved on the outside of the main shaft (4). A motor assembly (2) is provided in the housing (1), and the motor assembly (2) is connected to the top of the main shaft (4), and drives the main shaft (4) to rotate under the action of drilling fluid; An impact part cavity is formed between the inner wall of the shell (1) and the outer wall of the main shaft (4), and an elastic telescopic member (6) and an impact part (5) are arranged in the impact part cavity. The top of the elastic telescopic member (6) is fixed, and the bottom is connected to the top of the impact part (5). A positioning member (51) is arranged on the impact part (5). A ratchet groove (42) matching with the positioning member (51) is formed on the outer wall of the main shaft (4), and the ratchet groove (42) is Z-shaped. When the positioning member (51) is located at the lowest point of the ratchet groove (42), the bottom of the shell (1) abuts against the impact part (5) and the main shaft (4), respectively. The ratchet groove (42) comprises an inclined section (421) and a vertical section (422) which are connected end to end in sequence.

2. The impact generator according to claim 1, characterized in that: A bypass hole (41) is formed at the top of the main shaft (4), and an axially penetrating drilling fluid passage hole (43) is provided inside the main shaft, wherein the bypass hole (41) is in communication with the drilling fluid passage hole (43).

3. The impact generator according to claim 1, characterized in that: The motor assembly (2) comprises a rotor (21) and a stator (22); the rotor (21) is connected to the top of the main shaft (4) via a coupling (3); and the stator (22) is fixed on the inner wall of the housing (1).

4. The impact generator according to claim 1, characterized in that: The housing (1) comprises an upper limit member (11) and a lower limit member (12) which are arranged on the inner wall and are in an annular shape. The top of the elastic telescopic member (6) is fixed on the upper limit member (11). When the positioning member (51) is located at the lowest point of the ratchet groove (42), the bottom of the impact portion (5) abuts against the lower limit member (12).

5. The impact generator according to claim 1, characterized in that: A thrust bearing (7) is provided between the bottom of the housing (1) and the main shaft (4).

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