CN106703685B - A kind of high-voltage pulse power hammer drilling tool - Google Patents

Abstract

The invention discloses a high-voltage pulse power hammer drilling tool, which includes a bottom-hole high-voltage pulse power device and a pulse power hammer; low-pressure circulating drilling fluid enters the bottom-hole high-voltage pulse power device through a drill pipe, and is generated under the action of high-intensity pulse voltage Plasma, due to the properties of plasma with high-density storage energy and high expansion effect, the discharge channel expands rapidly outward, forming water shock waves in the water medium and entering the power hammer, and the power hammer reciprocates under the action of pressure to break rocks. The invention can reduce the drilling cost, reduce the energy transmission loss acting on broken rocks, reduce energy consumption, be applicable to various complicated hard formations, and improve the drilling efficiency.

Description

A high-voltage pulse power hammer drilling tool

technical field

The invention relates to the fields of drilling tools such as geology and oil and gas exploration and development, in particular to a high-voltage pulse power hammer drilling tool.

Background technique

In recent years, hydraulic percussion rotary drilling technology has made good progress in drilling hole depth, hole diameter, drilling efficiency and bit life, etc., and has been widely used in different formations and different geological explorations and engineering explorations, with remarkable results. But there are also some flaws. Since the high-pressure liquid flow is the driving force of the power hammer, it pushes the hammer to reciprocate. Therefore, as the drilling depth deepens, the requirement for pump pressure gradually increases. The pump pressure must not only overcome the impactor and the resistance along the way, but also meet the working requirements of the power hammer. Only when a certain pump pressure is reached, the power hammer can start to work.

High-voltage pulse discharge in water means that the high voltage charged into the capacitor is pulse-discharged in water to form a plasma through channel, and the discharge channel expands outward under the action of internal high temperature and high pressure to form a powerful shock wave, realizing the conversion of electrical energy to mechanical energy. Also called the electrohydraulic effect. In recent years, high-voltage pulsed plasma technology has been gradually applied to rock crushing, and has achieved certain results, but there are also some defects.

Contents of the invention

The object of the present invention is to provide a high-voltage pulse power hammer drill.

The invention includes a bottom-hole high-voltage pulse power device and a power hammer;

The bottom-hole high-voltage pulse power device includes a casing, an upper end cover, a high-voltage pulse generating cavity, a lower end cover and a hollow cavity; the main body of the casing is cylindrical, and the upper and lower ends of the casing are provided with an upper joint and a lower joint, and the upper joint and the lower joint have respectively Internal thread and external thread, there are positive terminal and negative terminal on both sides of the upper end of the shell, the high-voltage positive electrode cable and negative electrode cable are respectively connected to the ground high-voltage pulse power supply from the terminal, and the lower end of the shell is provided with steps for the placement of the upper structure The upper end cover is a circular plate structure with a boss, and is provided with a central hole and an annular through hole, the drilling fluid enters the high-pressure pulse generation chamber from the drill pipe through the annular through hole, and a one-way valve is installed on the upper part of the boss; The one-way valve is composed of a one-way valve body, a sealing ring and a spring. The one-way valve body moves downward under the action of the drilling fluid pressure to open the inlet to allow the drilling fluid to flow in; the lower end cover is a flat plate In the center of the lower end cover, there is a central hole that is installed with the high-voltage positive electrode and the upper end cover. The center hole is surrounded by a ring-shaped through hole, which is used as a high-pressure drilling fluid outflow channel and is fixed on the steps of the shell;

The high-voltage pulse generating chamber includes a first insulating spacer, a second insulating spacer, a third insulating spacer, a high-voltage positive electrode, a negative electrode, an insulating spacer, the first insulating spacer, the second insulating spacer, the second The annular structure of the three insulating spacers is provided with a groove and a central hole, the high-voltage positive electrode is a hollow metal tube, the insulating spacer is a cylindrical structure with a central hole, and the negative electrode is a thin-walled tube structure; the top surface of the lower end cover is from The central axis, the second insulating spacer, the insulating spacer, the high-voltage positive electrode, the negative electrode, the third insulating spacer and the first insulating spacer are placed in sequence from bottom to top, and the high-voltage positive electrode passes through the second insulating spacer and the third insulating spacer. The groove of the spacer ring is fixed, the negative electrode is fixed by the insulating spacer and the third insulating spacer, the third insulating spacer and the insulating spacer are pressed together by the upper end cover, the lower end cover and the central shaft, and the high voltage positive electrode and the negative electrode A gap between electrodes is left to generate high-pressure plasma; the hollow cavity is the drilling fluid flow space reserved between the lower surface of the lower end cover of the shell and the lower joint of the shell; the shell, the upper end cover and the lower end cover are Stainless steel material; the first insulation spacer ring, the second insulation spacer ring, the third insulation spacer ring and the insulation spacer sleeve are made of glass fiber nylon material; the central shaft is made of nylon material, and the upper and lower ends of the central shaft have threads and are used It is fixed with the upper end cover and the lower end cover by bolts; the high-voltage positive electrode and negative electrode are made of stainless steel.

The power hammer includes a shell, an anvil, and a piston hammer spring. The power hammer uses the high-pressure pulse hydraulic shock wave generated by the high-pressure pulse power device at the bottom of the well as the working power to continuously apply impact loads to the rock.

In the drilling project, the present invention connects the drill pipe with the ground drilling equipment, loads the high-intensity pulse voltage to the bottom-hole high-voltage pulse power device through the high-voltage electrode cable and the negative cable, and connects the power hammer and the drill bit in the downhole. The cable is connected to the ground pulse power supply and the accumulator.

The present invention has the following advantages:

(1) When the high-voltage pulse hammer drilling tool is used for drilling, the plasma generated by the high-voltage breakdown has the characteristics of high temperature and high pressure, and at the same time, the plasma channel expands outward and compresses the surrounding drilling fluid to form a pressure shock wave , directly into the power hammer to meet the needs of high-pressure liquid flow when the power hammer is working, and the impact frequency and impact energy of the power hammer will also increase with the increase of the pump pressure.

(2) The pulse discharge electrode adopts a coaxial structure, which effectively avoids the instability of the discharge distance.

(3) When drilling deep formations, the requirements for the mud pump are reduced, the pressure of the drilling fluid at the inlet is reduced, the loss of pressure along the way is reduced, the drilling efficiency is improved, and the drilling cost is reduced.

(4) It is suitable for various types of power hammers and meets the requirements for drilling into formations.

Description of drawings

Fig. 1 is a schematic diagram of the structure of the present invention.

Fig. 2 is a schematic diagram of the structure of the bottom-hole high-pressure pulse power device.

Fig. 3 is a schematic diagram of the structure of the upper end cover of the bottom-hole high-voltage pulse device.

Fig. 4 is a schematic diagram of the insulating ring structure of the bottom-hole high-voltage pulse device.

Fig. 5 is a schematic diagram of the insulating ring structure of the bottom-hole high-voltage pulse device.

Fig. 6 is a schematic diagram of the structure of the insulating spacer of the bottom-hole high-voltage pulse device.

Fig. 7 is a schematic diagram of the structure of the lower end cover of the bottom-hole high-voltage pulse device.

Fig. 8 is a working diagram of the present invention.

In the figure: 1-drill pipe, 2-bottomhole high-pressure pulse power device, 3-sealing ring, 4-spring, 5-negative terminal, 6-first bolt, 26-second bolt, 7-central shaft, 8 -Upper end cover, 9-First insulating spacer, 12-Second insulating spacer, 21-Third insulating spacer, 11-Negative electrode cable, 13-Through hole, 14-Hollow cavity, 15-Lower connector, 16 -Upper connector, 17-positive terminal, 18-high voltage positive electrode cable, 19-through hole of upper end cover, 20-center hole of upper end cover, 22-high voltage positive electrode, 23-negative electrode, 24-insulation spacer, 25- Lower end cover, 27-center hole of lower end cover, 28-outer shell, 29-power hammer, 30-drill bit, 31-drilling fluid flow channel, 32-drilling formation, 33-one-way valve body.

Detailed ways

As shown in Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6 and Fig. 7, the present invention includes a bottom-hole high-pressure pulse power device 2 and a power hammer 29;

The bottom-hole high-voltage pulse power device 2 includes a casing 28, an upper end cover 8, a high-voltage pulse generating chamber, a lower end cover 25 and a hollow cavity 14; the main body of the casing 28 is cylindrical, and the upper and lower ends of the casing 28 are provided with an upper joint 16 and a lower joint 15. The upper joint 16 and the lower joint 15 have internal threads and external threads respectively, and the positive terminal 17 and the negative terminal 5 are provided on both sides of the upper end of the shell 28, and the high-voltage positive electrode cable 18 and the negative electrode cable 11 are respectively connected from the terminal To the ground high-voltage pulse power supply, the lower end of the shell 28 is provided with steps for placing the upper structure; the upper end cover 8 is a circular plate structure with a boss, and is provided with a central hole 20 and an annular through hole 19, through which the drilling fluid passes The annular through hole 19 enters the high-pressure pulse generation chamber from the drill pipe, and a check valve is installed on the top of the boss; the check valve is composed of a check valve body 33, a sealing ring 3 and a spring 4, and the check valve body 33 is formed during drilling. Move downward under the action of hydraulic pressure to open the inlet, so that the drilling fluid flows in; the lower end cover 25 is flat, and the center of the lower end cover 25 is provided with a central hole 27 installed with the high-voltage positive electrode 22 and the upper end cover 8, The central hole 27 is surrounded by an annular through hole 13, which is used as a high-pressure drilling fluid outflow channel and is fixed on the steps of the shell 28;

The high-voltage pulse generation chamber includes a first insulating spacer 9, a second insulating spacer 12, a third insulating spacer 21, a high-voltage positive electrode 22, a negative electrode 23, an insulating spacer 24, the first insulating spacer 9, The annular structures of the second insulating spacer ring 12 and the third insulating spacer ring 21 are provided with a groove and a central hole, the high-voltage positive electrode 22 is a hollow metal tube, and the insulating spacer 24 is a cylindrical structure with a central hole. The electrode 23 is a thin-walled tube structure; the top surface of the lower end cover 25 is arranged in sequence from bottom to top with the central axis 7, the second insulating spacer 12, the insulating spacer 24, the high-voltage positive electrode 22, the negative electrode 23, and the third insulating spacer 21 and the first insulating spacer 9, the high-voltage positive electrode 22 is fixed by the grooves of the second insulating spacer 12 and the third insulating spacer 21, the negative electrode 23 is fixed by the insulating spacer 24 and the third insulating spacer 21, and the third The insulating spacer ring 21 and the insulating spacer 24 are compressed by the upper end cover 8, the lower end cover 25 and the central axis 7, and an inter-electrode gap 10 is left between the high-voltage positive electrode 22 and the negative electrode 23 to generate high-voltage plasma; the hollow The cavity 14 is the drilling fluid flow space reserved between the lower surface of the lower end cover 25 of the casing 28 and the lower joint 15 of the casing 28; the casing 28, the upper end cover 8 and the lower end cover 25 are made of stainless steel; An insulating spacer ring 9, a second insulating spacer ring 12, a third insulating spacer ring 21, and an insulating spacer sleeve 24 are made of glass fiber nylon material; the central shaft 7 is made of nylon material, and the upper and lower ends of the central shaft 7 have threads and bolts Fix it with the upper end cap 8 and the lower end cap 25; the high-voltage positive electrode 22 and negative electrode 23 are made of stainless steel.

The power hammer 29 includes a casing, an anvil, and a piston hammer spring. The power hammer 29 uses the high-pressure pulse hydraulic shock wave generated by the bottom-hole high-voltage pulse power device as the working power to continuously apply impact loads to the rock.

Working process of the present invention is as follows:

As shown in Figure 8, in the drilling project, the high-voltage pulse power hammer drill is connected to the drill bit 30, and the device is connected to the ground pulse power supply and other equipment through the high-voltage positive cable 18 and negative cable 11. The high-intensity voltage generated by the ground pulse power supply is loaded to the high-voltage positive electrode 22 and the negative electrode 23 through the high-voltage positive electrode cable 18 . The drilling fluid is passed from the ground surface through the mud pump to the bottom hole high-pressure pulse power device 2 through the drill pipe 1. First, the one-way valve body 33 moves downward under the action of the drilling fluid pressure, the device inlet is opened, and the drilling fluid passes through the upper end cover. The hole 19, the first insulating spacer ring 9 and the second insulating spacer ring 21 enter the inter-electrode gap 10, and under the action of high voltage, a high-voltage plasma is generated between the discharge electrodes, which makes the discharge circuit conduction and the energy stored in the capacitor is quickly released As a result, the pressure and temperature in the inter-electrode gap 10 rise sharply. Due to the high-density storage energy and high expansion effect of the plasma, the discharge channel expands outward rapidly, forming a water shock wave in the water medium, and entering the hollow cavity 14. , and enter the power hammer 29 through the through hole 13 of the lower end cover. When the high-pressure drilling fluid enters the power hammer 29, it first acts on the lower part of the hammer of the power hammer 29, so that the hammer moves upward against its own gravity and the compression force of the spring At the same time, the spring stores energy, and the liquid outlet of the anvil is opened. When the hammer rises to the top, the pressure of the working chamber decreases, and the hammer moves downward under the action of its own gravity and the compression energy of the spring, impacts the anvil, and It is transmitted to the drill bit 30 to break the rock; while the impact is generated, the hammer closes the fluid outlet of the anvil, the pressure of the working chamber rises, the hammer reciprocates again, and the drilling fluid flows from the formation 32 to the The drilling fluid flow channel 31 of the drill pipe 1 returns to the surface.

In the construction process, different power hammers can be used according to the specific requirements of the drilling process to meet the needs of the working conditions.

Claims (2)

1. A high-voltage pulse power hammer drilling tool is characterized in that: it comprises a bottom-hole high-voltage pulse power device (2) and a power hammer (29); The bottom-hole high-voltage pulse power device (2) comprises a casing (28), an upper end cover (8), a high-voltage pulse generating cavity, a lower end cover (25) and a hollow cavity (14); the main body of the casing (28) is cylindrical, An upper joint (16) and a lower joint (15) are arranged at the upper end and the lower end of the shell (28), and the upper joint (16) and the lower joint (15) have internal threads and external threads respectively, and positive pole wiring is provided on both sides of the upper end of the shell (28). Post (17) and negative terminal (5), high-voltage positive electrode cable (18) and negative electrode cable (11) are respectively connected to the ground high-voltage pulse power supply from the terminal, and the lower end of the shell (28) is provided with a step for placing the upper structure; the upper end cover (8) is a circular plate structure with a boss, and is provided with a central hole (20) and an annular through hole (19), and the drilling fluid enters the high pressure from the drill pipe through the annular through hole (19). Pulse generation chamber, check valve installed on the boss top; said check valve is made up of check valve body (33), sealing ring (3) and spring (4), and check valve body (33) is in drilling hydraulic pressure Move downward under the action of force to open the inlet, so that the drilling fluid flows in; the lower end cover (25) is flat, and the center of the lower end cover (25) is provided with a high voltage positive electrode (22) and an upper end cover (8 ) installed center hole (27), the center hole (27) is surrounded by an annular through hole (13), which is used as a high-pressure drilling fluid outflow channel, and is fixed on the step of the casing (28); The high-voltage pulse generating chamber includes a first insulating spacer (9), a second insulating spacer (12), a third insulating spacer (21), a high-voltage positive electrode (22), a negative electrode (23), an insulating spacer The sleeve (24), the annular structure of the first insulating spacer ring (9), the second insulating spacer ring (12), and the third insulating spacer ring (21) is provided with a groove and a central hole, and the high-voltage positive electrode (22) is Hollow metal tube, the insulating spacer (24) is a cylindrical structure with a central hole, the negative electrode (23) is a thin-walled tube structure; the top surface of the lower end cover (25) is arranged in sequence from bottom to top with the central axis (7) , the second insulating spacer (12), the insulating spacer (24), the high voltage positive electrode (22), the negative electrode (23), the third insulating spacer (21) and the first insulating spacer (9), the high voltage positive The electrode (22) is fixed by the grooves of the second insulating spacer (12) and the third insulating spacer (21), and the negative electrode (23) is fixed by the insulating spacer (24) and the third insulating spacer (21), The third insulating spacer (21) and the insulating spacer (24) are compressed by the upper end cover (8), the lower end cover (25) and the central shaft (7), between the high-voltage positive electrode (22) and the negative electrode (23) There is an interpolar gap (10) to generate high-pressure plasma; the hollow cavity (14) is reserved between the lower surface of the lower end cover (25) of the casing (28) and the lower joint (15) of the casing (28) The drilling fluid flow space; the upper and lower ends of the central shaft (7) have threads and are fixed with the upper end cover (8) and the lower end cover (25) with bolts. 2. A kind of high-voltage pulse power hammer drilling tool according to claim 1, characterized in that: said casing (28), upper end cover (8) and lower end cover (25) are made of stainless steel; said first The insulating spacer ring (9), the second insulating spacer ring (12), the third insulating spacer ring (21) and the insulating spacer sleeve (24) are glass fiber nylon material; the central axis (7) is nylon material; the The above-mentioned high-voltage positive electrode (22) and negative electrode (23) are made of stainless steel.