A downhole rotary jet eddy current tool

Abstract

The present invention provides a downhole rotary jet vortex tool, comprising an upper joint and a jet body connected in sequence. Among them, blades are evenly spaced along the circumferential direction on the inner side surface of one end of the jet body close to the upper joint. One end of the jet body away from the upper joint is provided with nozzles evenly spaced along the circumferential direction. The downhole rotary jet vortex tool provided by the present invention is designed for the characteristics of natural gas hydrate reservoirs, and is used for automatic rotary jetting of the reservoir during drilling or hot injection exploitation of the hydrate reservoir, thereby improving the hydrate crushing rate, strengthening the gas-liquid-solid three-phase vortex effect at the bottom of the well, effectively improving the flow state of the multiphase flow at the bottom of the well, and achieving efficient hydrate exploitation.

Description

Technical Field

[0001] The invention relates to the technical field of natural gas hydrate development and exploitation, and in particular to an underground rotary jet vortex tool. Background Art

[0002] Globally, the development of natural gas hydrates is currently in the stage of research, testing and trial production. Five countries, including China and the United States, have conducted trial production of natural gas hydrates and have achieved some successful trial production experience. The trial production experience shows that pressure reduction and heat injection are better ways to develop natural gas hydrates. In terms of trial production methods and trial production system devices, different countries have adopted different methods and devices for different mining conditions, and a recognized technically reliable and economical mining and trial production system has not yet been formed.

[0003] At present, the main methods for hydrate extraction include heating extraction, pressure reduction, chemical reagent, carbon dioxide replacement, solid fluidization, etc. Among them, heat injection extraction refers to pumping steam, hot water, hot brine or other hot fluids from the ground into the natural gas hydrate reservoir to increase the temperature and achieve the purpose of hydrate decomposition. Although there are hydrate extraction devices in the existing heat injection technology, continuous extraction cannot be achieved. Research on downhole tools suitable for the heat injection method to extract natural gas hydrates and improve extraction efficiency is particularly important for the commercial extraction of natural gas hydrates.

[0004] At present, the recovery devices suitable for natural gas hydrate exploitation in the existing technology do not take into account the impact of the bottom flow state of the hydrate storage well on the hydrate exploitation effect, do not fully consider the improvement of the heat injection method and the improvement of the heat injection efficiency, and are not designed for the enhancement of the gas-liquid-solid three-phase flow state. The effect on improving the hydrate fragmentation rate is limited, which limits the potential for commercial promotion and application. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a downhole rotary jet vortex tool. According to the characteristics of the natural gas hydrate reservoir, the tool is used to automatically rotate and jet the reservoir when the hydrate reservoir is opened for drilling or hot injection production, thereby improving the hydrate crushing rate, strengthening the gas-liquid-solid three-phase vortex effect at the bottom of the well, effectively improving the flow state of the multiphase flow at the bottom of the well, and achieving efficient hydrate production.

[0006] In order to solve the above technical problems, the technical solution proposed by the present invention is:

[0007] A downhole rotary jet vortex tool comprises an upper joint and a jet body connected in sequence, wherein blades are evenly spaced along the circumferential direction on the inner side surface of one end of the jet body close to the upper joint, and nozzles are evenly spaced along the circumferential direction on one end of the jet body away from the upper joint.

[0008] The downhole rotary jet vortex tool according to the present invention is connected to the bottom of the drill pipe or the production pipe string for use, facing the hydrate reservoir. When the hydrate reservoir is opened for drilling or hot injection production, high-speed water or hot fluid is sprayed into the hydrate reservoir through the nozzle to effectively break the hydrate. At the same time, the high-speed fluid impacts the blades, pushing the jet body to rotate along the axis. Under the combined effect of the jet body's self-rotation and the nozzle, an efficient vortex effect is formed at the bottom of the hydrate reservoir, thereby increasing the hydrate breakage rate, strengthening the gas-liquid-solid three-phase vortex effect at the bottom of the well, effectively improving the multiphase flow state at the bottom of the well, and achieving efficient hydrate production.

[0009] For the above technical solution, further improvements as described below can be made.

[0010] According to the downhole rotary jet vortex tool of the present invention, in a preferred embodiment, a jet through hole is provided on the jet body between the blades and the nozzle, and the axis of the jet through hole forms a preset angle with the axis of the jet body.

[0011] Furthermore, with the downhole rotary jet vortex tool of the present invention, when the hydrate reservoir is opened for drilling or hot injection exploitation, high-speed water or hot fluid can be sprayed into the hydrate reservoir through the injection hole to effectively break up the hydrates. Under the combined effect of the self-rotation of the injection body, the angled injection hole and the nozzle, a high-efficiency vortex effect is further formed at the bottom of the hydrate reservoir, thereby greatly improving the hydrate crushing rate, strengthening the gas-liquid-solid three-phase vortex effect at the bottom of the hole, effectively improving the flow state of the multiphase flow at the bottom of the hole, and achieving efficient hydrate exploitation.

[0012] Furthermore, in a preferred embodiment, the preset angle is between 15° and 90°.

[0013] Setting the inclination angle of the injection through hole within the above range can ensure that the high-speed water or hot fluid sprayed through the injection through hole has the best effect on breaking the hydrate.

[0014] Further, in a preferred embodiment, the number of the injection through holes is at least 4.

[0015] The device comprises 4 or more injection holes, which can further improve the breaking effect of the high-speed water or hot fluid ejected through the injection holes on the hydrate.

[0016] Specifically, in a preferred embodiment, the nozzle is made of tungsten steel.

[0017] The nozzle is made of tungsten steel, with high structural strength and long service life.

[0018] Further, in a preferred embodiment, the number of nozzles is at least 4.

[0019] Including 4 or more nozzles can further improve the breaking effect of high-speed water or hot fluid sprayed through the nozzles on hydrates.

[0020] Further, in a preferred embodiment, the upper joint and the injection body are detachably connected to each other via a connecting component.

[0021] By providing connecting components to respectively connect the upper joint and the injection body, the structural strength of the entire tool can be effectively improved, and the entire tool can be easily assembled and disassembled.

[0022] Further, in a preferred embodiment, the connecting component includes a conversion bracket connected to the upper joint and a conversion sleeve sleeved on the conversion bracket, and the injection body is connected to the conversion sleeve.

[0023] The connecting component of the above structural form has a simple structure and is easy to install and disassemble.

[0024] Furthermore, in a preferred embodiment, a sealing ring is provided between the conversion bracket and the conversion sleeve.

[0025] By providing a sealing ring, the sealing performance of the tool can be further improved, effectively preventing the impact on the hydrate crushing effect due to leakage of high-pressure fluid or hot fluid during the working process.

[0026] Specifically, in a preferred embodiment, the blades are arranged on the inner side of the injection body by a keyway structure or welding.

[0027] The blades are arranged on the injection body through the above two connection forms, both of which can ensure stable and reliable connection and easy processing and arrangement.

[0028] Compared with the prior art, the advantages of the present invention are: according to the characteristics of natural gas hydrate reservoirs, the reservoir can be automatically rotated and sprayed when the hydrate reservoir is opened for drilling or hot injection production, thereby improving the hydrate crushing rate, strengthening the gas-liquid-solid three-phase vortex effect at the bottom of the well, effectively improving the multiphase flow state at the bottom of the well, and achieving efficient hydrate production. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings, wherein:

[0030] Figure 1 The overall structure of the downhole rotary jet vortex tool according to an embodiment of the present invention is schematically shown. DETAILED DESCRIPTION

[0031] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but the protection scope of the present invention is not limited thereby.

[0032] Figure 1The overall structure of a downhole rotary jet vortex tool 10 according to an embodiment of the present invention is schematically shown.

[0033] like Figure 1 As shown, the downhole rotary jet vortex tool 10 of the embodiment of the present invention comprises an upper joint 1 and a jet body 2 connected in sequence. Among them, blades 21 are evenly spaced along the circumferential direction on the inner side surface of one end of the jet body 2 close to the upper joint 1. Nozzles 22 are evenly spaced along the circumferential direction on the end of the jet body 2 away from the upper joint 1.

[0034] The downhole rotary jet vortex tool according to the embodiment of the present invention is connected to the bottom of the drill pipe or the production pipe string for use, facing the hydrate reservoir. When the hydrate reservoir is opened for drilling or hot injection production, high-speed water or hot fluid is sprayed into the hydrate reservoir through the nozzle to effectively break the hydrate. At the same time, the high-speed fluid impacts the blades, pushing the jet body to rotate along the axis. Under the combined effect of the jet body's self-rotation and the nozzle, an efficient vortex effect is formed at the bottom of the hydrate reservoir, thereby increasing the hydrate breakage rate, strengthening the gas-liquid-solid three-phase vortex effect at the bottom of the well, and effectively improving the multiphase flow state at the bottom of the well, so as to achieve efficient hydrate production.

[0035] Specifically, in this embodiment, the nozzle 22 is made of tungsten steel and is arranged on the injection body 2 through a welding structure 24. The nozzle made of tungsten steel has high structural strength and long service life. The welding structure is used to fix the connection, which can further enhance the structural strength of the entire tool. Further, in this embodiment, the nozzle 22 includes at least 4. Including 4 or more nozzles can further improve the crushing effect of high-speed water or hot fluid ejected through the nozzle on hydrates.

[0036] Specifically, in this embodiment, the blade 21 is arranged on the inner side of the injection body 2 by a keyway structure or welding. The blade is arranged on the injection body by the above two connection forms, which can ensure stable and reliable connection and easy processing and arrangement. Specifically, in this embodiment, both ends of the upper joint and both ends of the injection body are provided with standard oil pipe threads, which are convenient for connection with drill pipes or production pipe strings.

[0037] like Figure 1As shown, further, in this embodiment, a jet through hole 23 is provided on the jet body 2 at a position between the blade 21 and the nozzle 22, and the axis of the jet through hole 23 is at a preset angle a with the axis of the jet body 2. Further, in the downhole rotary jet vortex tool of the embodiment of the present invention, when the hydrate reservoir is opened for drilling or hot injection exploitation, high-speed water or hot fluid can be sprayed into the hydrate reservoir through the jet through hole to effectively crush the hydrate, and under the comprehensive effect of the self-rotation of the jet body, the angled jet through hole and the nozzle, a high-efficiency vortex effect is further formed at the bottom of the hydrate reservoir, thereby greatly improving the hydrate crushing rate, strengthening the gas-liquid-solid three-phase vortex effect at the bottom of the well, effectively improving the multiphase flow state at the bottom of the well, and realizing the efficient exploitation effect of hydrate. Specifically, in this embodiment, the preset angle a is between 15° and 90°. Setting the inclination angle of the jet through hole within the above range can ensure that the high-speed water or hot fluid ejected through the jet through hole has the best crushing effect on the hydrate. Further, in this embodiment, the jet through hole 23 includes at least 4. The device comprises 4 or more injection holes, which can further improve the breaking effect of the high-speed water or hot fluid ejected through the injection holes on the hydrate.

[0038] like Figure 1 As shown, further, in this embodiment, the upper joint 1 and the injection body 2 are connected to each other in a detachable manner such as a threaded connection through a connecting component 3. By setting a connecting component to connect the upper joint and the injection body respectively, the structural strength of the entire tool can be effectively improved, and the entire tool can be easy to assemble and disassemble. Specifically, in this embodiment, the connecting component 3 includes a conversion support 31 connected to the upper joint 1 and a conversion sleeve 32 sleeved on the conversion support 31, and the injection body 2 is connected to the conversion sleeve 32 in a threaded connection. The connecting component of the above-mentioned structural form has a simple structure and is easy to install and disassemble. Further, specifically, in this embodiment, a sealing ring 33 is provided between the conversion support 31 and the conversion sleeve 32. By providing a sealing ring, the sealing performance of the tool can be further improved, and the impact on the crushing effect of the hydrate due to the leakage of a high degree of fluid or hot fluid during the working process can be effectively avoided.

[0039] The working method of the downhole rotary jet eddy current tool 10 according to the embodiment of the present invention specifically comprises the following steps:

[0040] (1) Connect the tool 10 to the bottom of the drill pipe or production pipe string, facing the hydrate reservoir;

[0041] (2) When the hydrate reservoir is opened for drilling or hot injection exploitation, high-speed water or hot fluid is sprayed into the hydrate reservoir through the injection through hole 23 and the tungsten steel nozzle 22, effectively breaking up the hydrate;

[0042] (3) At the same time, the high-speed fluid impacts the blades 21, pushing the injection body 2 to rotate along the axis; under the combined effect of the injection body 2's rotation, the injection through hole 23 with an angle a, and the tungsten steel nozzle 22, a high-efficiency vortex effect is formed at the bottom of the hydrate reservoir, thereby improving the efficiency of hydrate development and production and reducing the secondary generation of hydrates during production.

[0043] According to the above embodiments, it can be seen that the downhole rotary jet vortex tool involved in the present invention is used for the characteristics of natural gas hydrate reservoirs to automatically perform rotary jetting on the reservoir when the hydrate reservoir is opened for drilling or hot injection production, thereby improving the hydrate crushing rate, strengthening the gas-liquid-solid three-phase vortex effect at the bottom of the hole, effectively improving the flow state of the multiphase flow at the bottom of the hole, and achieving efficient hydrate production.

[0044] Although the present invention has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced by equivalents without departing from the scope of the present invention. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A downhole rotary jet eddy current tool, characterized in that: It includes an upper joint and a spray body connected in sequence; wherein, On the inner side surface of one end of the injection body close to the upper joint, blades are evenly spaced in the circumferential direction, and the blades are arranged on the inner side surface of the injection body by a keyway structure or welding; The end of the spray body away from the upper joint is provided with nozzles evenly spaced in the circumferential direction; The injection body is provided with an injection through hole at a position between the blade and the nozzle, and the axis of the injection through hole forms a preset angle with the axis of the injection body; When the hydrate reservoir is opened for drilling or hot injection exploitation, high-speed water or hot fluid is sprayed into the hydrate reservoir through the nozzle and the injection through hole, effectively breaking up the hydrate. At the same time, the high-speed fluid impacts the blades, driving the injection body to rotate along the axis. Under the combined effect of the injection body's self-rotation and the nozzle, a high-efficiency vortex effect is formed at the bottom of the hydrate reservoir. Under the combined effect of the injection body's self-rotation, the angled injection through hole and the nozzle, a high-efficiency vortex effect is further formed at the bottom of the hydrate reservoir. The upper joint and the spray body are detachably connected to each other via a connecting component; The connecting component comprises a conversion bracket connected to the upper joint and a conversion sleeve sleeved on the conversion bracket, and the injection body is connected to the conversion sleeve; A sealing ring is provided between the conversion bracket and the conversion sleeve; The conversion bracket is inserted into the upper joint and threadedly connected to the upper joint, and the injection body is threadedly connected to the conversion sleeve; A first limiting protrusion extending radially outward is formed at one end of the conversion bracket away from the upper joint, the first limiting protrusion is spaced from the upper joint, and the first limiting protrusion and the upper joint form a first limiting groove, and a sealing ring is arranged on the circumferential side surface of the first limiting protrusion; A second limiting protrusion extending radially inward is formed at one end of the conversion sleeve away from the injection body, and the second limiting protrusion is inserted into the first limiting groove and connected to the conversion support.

2. The downhole rotary jet eddy current tool according to claim 1, characterized in that: The preset angle is between 15° and 90°.

3. The downhole rotary jet eddy current tool according to claim 2, characterized in that: The number of the injection through holes is at least 4.

4. The downhole rotary jet eddy current tool according to any one of claims 1 to 3, characterized in that: The nozzle is made of tungsten steel.

5. The downhole rotary jet eddy current tool according to any one of claims 1 to 3, characterized in that: The number of the nozzles is at least 4.

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