Near-bit stress wave clipping device

Abstract

The invention belongs to the technical field of down-the-hole hammer drilling corollary equipment, and particularly relates to a near-bit stress wave clipping device which comprises a semicircular clamp, an anvil, an octagonal sleeve, a mounting step, a screw, a low-resistance clipping gasket, a high-resistance clipping gasket and a pressing ring. Stress waves are reflected multiple times through multiple interfaces, the stress wave peak value is effectively reduced, impact energy is reduced, and therefore a matched drill rod is protected; deformation of the whole device is small in the vibration reduction process, and the assembling relation of all parts in the whole equipment cannot be affected; according to the protection device, no easy-to-damage structure exists, the gasket sets are flat gaskets, clamped through screws and limited through the pressing rings, and the whole device is small in displacement and long in service life when being impacted; the protection device is simple in structure, convenient to install, low in manufacturing cost and beneficial to prolonging the service life of the drill rod, shortening the tripping time and improving the drilling efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of down-the-hole hammer drilling supporting equipment, and in particular relates to a near-drill-bit clipper. Background Art

[0002] With the increasing depletion of shallow mineral resources and the accelerated exploration of new clean energy sources such as hot dry rocks, it is particularly urgent to develop a technology that can achieve efficient and low-cost drilling in hard and difficult-to-penetrate formations. Studies have shown that for formations with high abrasiveness and low drillability, the use of impact rotary drilling technology can significantly improve drilling efficiency compared to traditional rotary drilling methods.

[0003] However, while the down-the-hole hammer uses its powerful impact energy to break rocks, it also applies a certain proportion of impact energy to the drill pipe. The vibration of the drill pipe caused by this energy often causes fatigue cracks inside it, leading to fatigue failure.

[0004] Therefore, those skilled in the art need a new technology to solve the problems raised in the above background technology. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a device and a system for solving the problems existing in the background technology.

[0006] A near-drill-bit stress wave clipper, characterized in that it comprises a semicircular clamp, an anvil, an octagonal sleeve, a screw, a clipping gasket set and a clamping ring;

[0007] The anvil is a hollow structure with two ends open, and a groove and a step structure along the circumferential direction are arranged on its outer wall, the octagonal sleeve is arranged on the step structure, and the semicircular clamp is arranged in the groove;

[0008] The octagonal sleeve is cylindrical, and the inner wall is provided with a structure matching the step structure, and the inner wall of the octagonal sleeve is provided with a mounting step;

[0009] The clipping gasket group includes low-resistance clipping gaskets and high-resistance clipping gaskets, and the low-resistance clipping gaskets and the high-resistance clipping gaskets are arranged regularly;

[0010] The chopping gasket set is arranged on the installation step by means of the screws, and a clamping ring for limiting the chopping gasket set is arranged at the end of the screw.

[0011] The inner wall of the anvil is provided with an internal thread section.

[0012] The low-resistance clipping gaskets and the high-resistance clipping gaskets are arranged in the order of increasing wave impedance.

[0013] The low-resistance clipping gaskets and the high-resistance clipping gaskets are arranged alternately.

[0014] The inner cavity of the anvil includes a straight section, a transition section and a tapered section, which are connected in sequence, and the inner wall of the tapered section is provided with a threaded section; the straight section is connected to the drill rod, and the tapered section is connected to the down-the-hole hammer and the drill bit through the threaded section.

[0015] The outer wall of the octagonal sleeve includes a cylindrical section and a truncated cone section. The diameter of the cylindrical section is the same as the position where the anvil has the largest diameter. The outer wall of the truncated cone section is provided with threads.

[0016] Through the above-mentioned design scheme, compared with the traditional vibration reduction method that simply relies on material deformation to absorb energy, the present application reflects part of the stress wave through different interface wave impedances, reflects the stress wave multiple times through multiple interfaces, effectively reduces the stress wave peak value, reduces the impact energy, and thus protects the matching drill rod;; the overall device deforms slightly during the vibration reduction process, and will not affect the assembly relationship between the various components in the whole set of equipment; there is no vulnerable structure in the protection device of the present application, and the gasket group is all flat gaskets, clamped with screws, and limited by a clamping ring. The entire device has a small displacement when subjected to impact and has a long service life; the protection device of the present application has a simple structure, is easy to install, and has a low manufacturing cost, which is conducive to improving the service life of the drill rod, reducing the time of drilling and drilling, and improving the drilling efficiency; because the impact work of the down-the-hole hammer is large, the impact energy transmitted from the drill bit to the drill rod is large, in order to avoid damage to the drill rod, the matching drill rod is mostly made of high-strength alloy steel, which is expensive; the use of the present application can improve the service life of its matching drill rod, thereby reducing the actual use cost of the down-the-hole hammer and reducing the cost of hard rock drilling. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention is further described below with reference to the accompanying drawings and specific embodiments:

[0018] Figure 1 It is a schematic diagram of the mechanism of the present invention;

[0019] Figure 2 for Figure 1 Cross-sectional view along the DD direction;

[0020] 1-semicircle card, 2-anvil, 201-straight section, 202-transition section, 203-tapered section, 3-octagonal sleeve, 301-installation step, 4-screw, 5-low-resistance clipping gasket, 6-high-resistance clipping gasket, 7-compression ring. DETAILED DESCRIPTION

[0021] The present application is further described with reference to the accompanying drawings:

[0022] A near-drill bit stress wave clipper, characterized by comprising a semicircular clamp 1, an anvil 2, an octagonal sleeve 3, a screw 4, a clipping gasket set and a clamping ring 7;

[0023] The anvil 2 is a hollow structure with two ends open, and a groove and a step structure are arranged on its outer wall along the circumferential direction. The octagonal sleeve 3 is sleeved on the step structure, and the semicircular clamp 1 is arranged in the groove;

[0024] The octagonal sleeve 3 is a hollow structure with openings at both ends, and the inner wall is provided with a structure adapted to the step structure, and the inner wall of the octagonal sleeve 3 is provided with an installation step 301;

[0025] The clipping gasket group includes a low-resistance clipping gasket 5 and a high-resistance clipping gasket 6, and the low-resistance clipping gasket 5 and the high-resistance clipping gasket 6 are arranged regularly;

[0026] The chopping gasket set is arranged on the installation step 301 by means of the screw 4 , and a clamping ring 7 for limiting the chopping gasket set is arranged at the end of the screw 4 .

[0027] The inner wall of the anvil 2 is provided with an internal thread section.

[0028] The low-resistance clipping gaskets 5 and the high-resistance clipping gaskets 6 are arranged in the order of increasing wave impedance.

[0029] The low-resistance clipping gaskets 5 and the high-resistance clipping gaskets 6 are arranged alternately.

[0030] The inner cavity of the anvil 2 includes a straight section 201, a transition section 202 and a tapered section 203, the straight section 201, the transition section 202 and the tapered section 203 are connected in sequence, and the inner wall of the tapered section 203 is provided with a threaded section; the straight section 201 is connected to the drill rod, and the tapered section 203 is connected to the down-the-hole hammer and the drill bit through the threaded section.

[0031] The outer wall of the octagonal sleeve 3 includes a cylindrical section and a truncated cone section. The diameter of the cylindrical section is the same as the position where the anvil 2 has the largest diameter. The outer wall of the truncated cone section is provided with threads.

[0032] The inner cavity of the anvil 2 is a circular hole liquid flow channel for fluid to pass through;

[0033] The gaskets in the gasket assembly may be arranged with equal cross-sections or with unequal cross-sections.

[0034] The gaskets in the gasket assembly may be arranged with equal thickness or with unequal thickness.

[0035] The contact surfaces of each gasket in the gasket assembly are finely ground to ensure good contact between the gaskets.

[0036] The present application aims to reduce the impact energy entering the drill pipe from the drill bit, thereby protecting the drill pipe, extending its service life, and reducing the risk of accidents caused by fatigue failure.

[0037] The present invention draws on the principle of reflection and transmission of stress waves at the interface of materials with different wave impedances. When the impact energy propagates from a high wave impedance material to a low wave impedance material (such as a shock-absorbing material), part of the energy will be reflected at the interface, thereby effectively reducing the energy transmitted to the drill pipe. In addition, the deformation energy characteristics of elastic or plastic materials are used to further reduce the amplitude of the stress wave.

[0038] The semicircular clamp 1 is clamped and fixed to the anvil 2 through a groove, and the semicircular clamp 2 limits the axial displacement of the octagonal sleeve 3 on the anvil 2 to ensure that the clipper is tightly connected as a whole.

[0039] Compared with the traditional vibration reduction method that simply relies on material deformation to absorb energy, the present invention reflects part of the stress wave through different interface wave impedances, reflects the stress wave multiple times through multiple interfaces, effectively reduces the peak value of the stress wave, reduces the impact energy, and thus protects the matching drill pipe. The overall device deforms slightly during the vibration reduction process, which will not affect the assembly relationship between the various components in the entire set of equipment.

[0040] The protective device of the present invention has no vulnerable structure, the gasket groups are all flat gaskets, clamped by screws, and limited by a clamping ring. The entire device has a small displacement when subjected to impact and has a long service life.

[0041] The protective device of the present invention has a simple structure, is easy to install, and has a low manufacturing cost, and is beneficial to prolonging the service life of the drill rod, reducing the time of drilling and drilling, and improving the drilling efficiency.

[0042] Because the impact work of the down-the-hole hammer is large, the impact energy transmitted from the drill bit to the drill rod is large. In order to avoid damage to the drill rod, the matching drill rod is mostly made of high-strength alloy steel, which is expensive. The application can increase the service life of the matching drill rod, thereby reducing the actual use cost of the down-the-hole hammer and the cost of hard rock drilling.

Claims

1. A near-drill-bit stress wave clipper, characterized in that: It comprises a semicircular clamp (1), an anvil (2), an octagonal sleeve (3), a screw (4), a wave cutting gasket set and a clamping ring (7); The anvil (2) is a hollow structure with two ends open, and a groove and a step structure are arranged on its outer wall along the circumferential direction, the octagonal sleeve (3) is sleeved on the step structure, and the semicircular clamp (1) is arranged in the groove; The octagonal sleeve (3) is a hollow structure with openings at both ends, the inner wall of which is provided with a structure matching the step structure, and the inner wall of the octagonal sleeve (3) is provided with an installation step (301); The clipping gasket group comprises a low-resistance clipping gasket (5) and a high-resistance clipping gasket (6), and the low-resistance clipping gasket (5) and the high-resistance clipping gasket (6) are arranged regularly; The chopping gasket set is arranged on the installation step (301) by means of the screw (4), and a clamping ring (7) for restricting the chopping gasket set is arranged at the end of the screw (4).

2. The near-drill-bit stress wave clipper according to claim 1, characterized in that: The inner wall of the anvil (2) is provided with an internal thread section.

3. The near-drill-bit stress wave clipper according to claim 1, characterized in that: The low-resistance wave-chopping gaskets (5) and the high-resistance wave-chopping gaskets (6) are arranged in the order of increasing wave impedance.

4. The near-drill-bit stress wave clipper according to claim 1, characterized in that: The low-resistance clipping gaskets (5) and the high-resistance clipping gaskets (6) are arranged alternately.

5. The near-drill-bit stress wave clipper according to claim 1, characterized in that: The inner cavity of the anvil (2) comprises a straight section (201), a transition section (202) and a tapered section (203); the straight section (201), the transition section (202) and the tapered section (203) are connected in sequence, and the inner wall of the tapered section (203) is provided with a threaded section; the straight section (201) is connected to a drill rod, and the tapered section (203) is connected to a down-the-hole hammer and a drill bit via the threaded section.

6. The near-drill-bit stress wave clipper according to claim 1, characterized in that: The outer wall of the octagonal sleeve (3) comprises a cylindrical section and a truncated cone section, the diameter of the cylindrical section being the same as the position where the diameter of the anvil (2) is the largest; and the outer wall of the truncated cone section is provided with threads.

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