Drilling fluid filter used for drilling orientation and capable of preventing abrasion and cavitation on inner wall of drill rod

Abstract

The drilling fluid filter comprises a hanging ring, an outer cylinder and an inner cylinder, the hanging ring is hung on the inner side of the upper portion of the drilling rod, the inner side of the lower end of the hanging ring is in threaded connection with the outer cylinder, a mounting table is arranged on the inner side of the lower end of the outer cylinder, and the middle of the mounting table is vertically communicated with the middle of the outer cylinder. A liquid channel with a downward opening is formed in the middle of the inner barrel, the inner barrel comprises a shuttle-shaped filter barrel and an installation barrel which are integrally arranged from top to bottom, the outer side of the middle of the installation barrel and the inner side of the installation table are detachably installed together, the shuttle-shaped filter barrel is located in the outer barrel, and a plurality of filter holes which are communicated inside and outside and communicated with the liquid channel are formed in the shuttle-shaped filter barrel. The device is reasonable and compact in structure and convenient to use, the double-layer design of the inner barrel and the outer barrel is adopted, the abrasion and cavitation effects directly acting on the inner wall of the drill rod are transferred to the replaceable filter inner barrel, and the shuttle-shaped filter barrel can reduce the flowing resistance of drilling fluid.

Description

Technical Field

[0001] The invention relates to the technical field of drilling fluid filters, in particular to a drilling fluid filter for preventing abrasion and cavitation of the inner wall of a drill pipe used for directional drilling. Background Art

[0002] Directional wells and horizontal wells require directional tools (MWD). Directional tools generally use pulse generators to transmit signals (well inclination, azimuth, natural gamma, etc.) to the ground. Among them, the pulse generator is easily blocked by large solid impurities in the drilling fluid and cannot transmit signals. When the pulse generator is blocked, the drill is forced to pull out and take out the pulse generator for maintenance. In order to protect the pulse generator from being blocked by large solid impurities in the drilling fluid, a filter cartridge must be installed in the drill pipe to filter large solid impurities in the drilling fluid and clean it regularly. The mud pump pumps the drilling fluid into the drill pipe, which is filtered through the drill pipe filter cartridge to remove large solid impurities, and then flows through the pulse generator. The pulse generator converts the signal (well inclination, azimuth, natural gamma, etc.) into a change in drilling fluid pressure, transmits it to the ground receiver, and decodes it to obtain the downhole signal (well inclination, azimuth, natural gamma, etc.).

[0003] Traditional filter cartridges such as Figure 1 As shown in the figure, the drilling fluid passes through the traditional filter body 1, diverges to the surroundings, impacts the drill pipe body 2, and flows downward. Taking a single hole as an example, when the drilling fluid is ejected at high speed from the filter hole 3 of the traditional filter and shot at the drill pipe body 2, there are two kinds of damage to the drill pipe body 2. First, the drilling fluid contains solid phase and sand, which has an abrasive effect on the drill pipe wall; second, after the drilling fluid is ejected from the single hole, a suction surface will be formed, forming a local low-pressure area. When the pressure is lower than the saturated vapor pressure of water, the liquid molecules in the liquid will be converted into gas molecules, and eventually a large number of bubbles will suddenly be generated, forming a "cavitation effect", which will cause cavitation to the drill pipe body 2. Due to long-term abrasion and cavitation, the drill pipe body 2 will generate dense and deep holes, the surface will become rough, and the effective thickness will be reduced. When the stress is large, the drill pipe body 2 will break from the filter screen, causing a drilling tool accident. Summary of the invention

[0004] The present invention provides a drilling fluid filter for directional drilling to prevent abrasion and cavitation of the inner wall of a drill pipe, which overcomes the shortcomings of the above-mentioned prior art and can effectively solve the problem that the existing drilling fluid filter cartridge causes abrasion and cavitation on the drill pipe body, resulting in the drill pipe being easily broken from the filter cartridge.

[0005] The technical solution of the present invention is achieved through the following measures: a drilling fluid filter for the inner wall of a drill pipe for directional drilling to prevent abrasion and cavitation, comprising a hanging ring, an outer tube and an inner tube. The hanging ring is suspended on the inner side of the upper part of the drill pipe, the inner side of the lower end of the hanging ring is threadedly connected to the outer tube, a mounting platform is provided on the inner side of the lower end of the outer tube, the middle part of the mounting platform is connected up and down with the middle part of the outer tube, the middle part of the inner tube is provided with a liquid channel opening downward, the inner tube comprises a shuttle-shaped filter cylinder and a mounting cylinder which are integrally arranged from top to bottom, the outer side of the middle part of the mounting cylinder and the inner side of the mounting platform are detachably mounted together, the shuttle-shaped filter cylinder is located in the outer tube, and the shuttle-shaped filter cylinder is provided with a plurality of filter holes which are connected inside and outside and connected to the liquid channel.

[0006] The following are further optimizations and / or improvements to the above technical solutions: The filter holes can be arranged obliquely upward, and the angle between the filter holes and the horizontal direction is 30° to 35°.

[0007] The total inner area of ​​the filter holes may be 1.2 to 1.5 times greater than the inner cross-sectional area of ​​the drill pipe.

[0008] The outer side of the middle part of the above-mentioned installation tube can be connected with the inner side of the installation platform through threads. An anti-rotation screw is installed on the installation platform, and the inner end of the anti-rotation screw is installed with the installation tube.

[0009] The above may also include a sealing ring, a female buckle is provided on the inner side of the upper part of the drill pipe, a male buckle is provided on the outer side of the lower part of the drill pipe, and a conical surface with a larger inner diameter at the top and a smaller inner diameter at the bottom is provided on the inner side of the drill pipe corresponding to the lower side of the female buckle. The hanging ring is hung on the inner side of the conical surface, and the outer side of the hanging ring forms a conical surface seal with the conical surface, and a sealing ring is provided between the hanging ring and the conical surface.

[0010] The inner cylinder can be made of abrasion-resistant material, and the filter holes are punched by laser.

[0011] The invention has a reasonable and compact structure and is easy to use. It adopts a double-layer design of inner and outer cylinders to transfer the abrasion and cavitation effects directly acting on the inner wall of the drill pipe to the replaceable filter inner cylinder, and the shuttle-shaped filter cylinder can reduce the flow resistance of the drilling fluid. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Attached Figure 1 It is a schematic diagram of the main half-section structure of the background technology.

[0013] Attached Figure 2 It is a schematic diagram of the front cross-sectional structure of an embodiment of the present invention.

[0014] The codes in the accompanying drawings are: 1 is a traditional filter body, 2 is a drill rod, 3 is a traditional filter hole, 4 is a hanging ring, 5 is a mounting platform, 6 is a liquid channel, 7 is a shuttle-shaped filter cylinder, 8 is a mounting cylinder, 9 is a filter hole, 10 is an anti-rotation screw, 11 is a female buckle, 12 is a male buckle, 13 is a cone surface, 14 is a sealing ring, and 15 is an outer cylinder. DETAILED DESCRIPTION

[0015] The present invention is not limited by the following embodiments, and specific implementation methods can be determined based on the technical solution of the present invention and actual conditions.

[0016] In the present invention, for the convenience of description, the relative position relationship of each component is described according to the attached Figure 1 The positional relationships such as front, back, top, bottom, left, and right are described according to the layout directions of the drawings in the specification.

[0017] The present invention will be further described below in conjunction with embodiments and drawings: Embodiment 1: As attached Figure 2 As shown, the drilling fluid filter for the inner wall of the drill pipe for directional drilling to prevent abrasion and cavitation includes a hanging ring 4, an outer tube 15, and an inner tube. The hanging ring 4 is suspended on the inner side of the upper part of the drill pipe, and the inner side of the lower end of the hanging ring 4 is threadedly connected to the outer tube 15. A mounting platform 5 is provided on the inner side of the lower end of the outer tube 15. The middle part of the mounting platform 5 is connected with the middle part of the outer tube 15 from top to bottom. A liquid channel 6 opening downward is provided in the middle part of the inner tube. The inner tube includes a shuttle-shaped filter cartridge 7 and a mounting cartridge 8 which are integrally arranged from top to bottom. The outer side of the middle part of the mounting cartridge 8 is detachably mounted together with the inner side of the mounting cartridge 5. The shuttle-shaped filter cartridge 7 is located in the outer tube 15. The shuttle-shaped filter cartridge 7 is provided with a plurality of filter holes 9 which are connected inside and outside and communicated with the liquid channel 6.

[0018] The outer cylinder 15 and the inner cylinder are double-layered and are detachably mounted together for easy cleaning and replacement. The drilling fluid enters the filter hole 9 of the shuttle filter cylinder 7 from the outer cylinder 15 and forms a jet toward the inside. The shuttle filter cylinder 7 adopts a streamlined design to reduce the flow resistance of the drilling fluid. The solid phase and sand in the drilling fluid will cause abrasion to the inner wall of the shuttle filter cylinder 7, and the high-speed drilling fluid jet will produce a cavitation effect. After a period of time, the inner surface of the inner cylinder will become rough, forming dense and deep holes, and the effective thickness will be reduced. However, the inner cylinder can be replaced according to the erosion situation. After the drilling fluid passes through the inner cylinder, it flows downward in a vertical direction, which greatly reduces the abrasive effect of the drilling fluid on the drill pipe body, and transfers the abrasion and cavitation formed on the inner wall of the drill pipe body to the inner cylinder, thereby reducing drilling tool accidents.

[0019] According to actual needs, the drilling fluid filter for the inner wall of the anti-abrasion and anti-cavitation drill pipe for directional drilling can be further optimized and / or improved: Embodiment 2: As attached Figure 2 As shown, the filter hole 9 is arranged obliquely upward, and the angle between the filter hole 9 and the horizontal direction is 30° to 35°. The drilling fluid enters the filter element along the 30° filter hole 9 to reduce the "cavitation effect".

[0020] Embodiment 3: As attached Figure 2As shown, the total area of ​​the inner side of the filter hole 9 is 1.2 to 1.5 times larger than the inner cross-sectional area of ​​the drill pipe. The throttling effect of the inner cylinder is reduced, and the erosion of the inner cylinder wall by the drilling fluid is reduced. The number and length of the inner cylinder filter holes 9 are determined according to the number of the new inner cylinder filter holes 9, and the length of the outer cylinder 15 is determined according to the length of the inner cylinder filter holes 9 of the new filter.

[0021] Embodiment 4: As attached Figure 2 As shown, the outer side of the middle part of the mounting tube 8 is connected with the inner side of the mounting platform 5 by threads, and an anti-rotation screw 10 is installed on the mounting platform 5, and the inner end of the anti-rotation screw 10 is installed with the mounting tube 8. In order to prevent the inner tube from being reversed and disengaged during use, the anti-rotation screw 10 is used to fix it.

[0022] Embodiment 5: As attached Figure 2 As shown, it also includes a sealing ring 14, a female buckle 11 is provided on the inner side of the upper part of the drill pipe, a male buckle 12 is provided on the outer side of the lower part of the drill pipe, and a conical surface 13 with a larger inner diameter at the top and a smaller inner diameter at the bottom is provided on the inner side of the drill pipe corresponding to the lower side of the female buckle 11, and a hanging ring 4 is hung on the inner side of the conical surface 13, and the outer side of the hanging ring 4 forms a conical surface seal with the conical surface 13, and a sealing ring 14 is provided between the hanging ring 4 and the conical surface 13. During the drilling and installation of a single root, the square drill pipe protection joint is removed to expose the drill pipe female section hoop, and the filter is placed in the drill pipe female section hoop female buckle 11, and the hanging ring 4 hangs the filter on the lower conical surface 13 of the female buckle 11, and the "O"-shaped sealing ring 14 forms a seal with the lower slope of the female buckle 11.

[0023] Embodiment 6: As attached Figure 2 As shown, the inner cylinder is made of abrasion-resistant material, and the filter hole 9 is punched by laser. The inner cylinder is made of hard alloy YG1535CrMo, hardened to improve wear resistance, and laser punching is used to make the inner wall of the filter hole 9 smoother and reduce wear.

[0024] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Non-essential technical features can be added or reduced according to actual needs to meet the requirements of different situations.

Claims

1. A drilling fluid filter for preventing abrasion and cavitation of the inner wall of a drill pipe for directional drilling, characterized in that It includes a hanging ring, an outer tube and an inner tube. The hanging ring is hung on the inner side of the upper part of the drill pipe. The inner side of the lower end of the hanging ring is threadedly connected with the outer tube. A mounting platform is provided on the inner side of the lower end of the outer tube. The middle part of the mounting platform is connected with the middle part of the outer tube up and down. The middle part of the inner tube is provided with a liquid channel opening downward. The inner tube includes a shuttle-shaped filter tube and a mounting tube which are integrally arranged from top to bottom. The outer side of the middle part of the mounting tube and the inner side of the mounting platform are detachably installed together. The shuttle-shaped filter tube is located in the outer tube. The shuttle-shaped filter tube is provided with a plurality of filter holes which are connected inside and outside and communicated with the liquid channel.

2. The drilling fluid filter for preventing abrasion and cavitation of the inner wall of the drill pipe for directional drilling according to claim 1, characterized in that The filter holes are arranged obliquely upward, and the angle between the filter holes and the horizontal direction is 30° to 35°.

3. The drilling fluid filter for preventing abrasion and cavitation of the inner wall of the drill pipe for directional drilling according to claim 1 or 2, characterized in that The total area inside the filter holes is 1.2 to 1.5 times larger than the inner cross-sectional area of ​​the drill pipe.

4. The drilling fluid filter for preventing abrasion and cavitation of the inner wall of the drill pipe for directional drilling according to claim 1 or 2, characterized in that The outer side of the middle part of the installation tube is connected with the inner side of the installation platform through threads, an anti-rotation screw is installed on the installation platform, and the inner end of the anti-rotation screw is installed with the installation tube.

5. The drilling fluid filter for preventing abrasion and cavitation of the inner wall of the drill pipe for directional drilling according to claim 3, characterized in that The outer side of the middle part of the installation tube is connected with the inner side of the installation platform through threads, an anti-rotation screw is installed on the installation platform, and the inner end of the anti-rotation screw is installed with the installation tube.

6. The drilling fluid filter for preventing abrasion and cavitation of the inner wall of the drill pipe for directional drilling according to claim 1, 2 or 5, characterized in that It also includes a sealing ring, a female buckle is provided on the inner side of the upper part of the drill pipe, a male buckle is provided on the outer side of the lower part of the drill pipe, and a conical surface with a larger inner diameter at the top and a smaller inner diameter at the bottom is provided on the inner side of the drill pipe corresponding to the lower side of the female buckle. A hanging ring is hung on the inner side of the conical surface, and a conical surface seal is formed between the hanging ring and the conical surface. A sealing ring is provided between the hanging ring and the conical surface.

7. The drilling fluid filter for preventing abrasion and cavitation of the inner wall of the drill pipe for directional drilling according to claim 3, characterized in that It also includes a sealing ring, a female buckle is provided on the inner side of the upper part of the drill pipe, a male buckle is provided on the outer side of the lower part of the drill pipe, and a conical surface with a larger inner diameter at the top and a smaller inner diameter at the bottom is provided on the inner side of the drill pipe corresponding to the lower side of the female buckle. A hanging ring is hung on the inner side of the conical surface, and a conical surface seal is formed between the hanging ring and the conical surface. A sealing ring is provided between the hanging ring and the conical surface.

8. The drilling fluid filter for preventing abrasion and cavitation of the inner wall of the drill pipe for directional drilling according to claim 4, characterized in that It also includes a sealing ring, a female buckle is provided on the inner side of the upper part of the drill pipe, a male buckle is provided on the outer side of the lower part of the drill pipe, and a conical surface with a larger inner diameter at the top and a smaller inner diameter at the bottom is provided on the inner side of the drill pipe corresponding to the lower side of the female buckle. A hanging ring is hung on the inner side of the conical surface, and a conical surface seal is formed between the hanging ring and the conical surface. A sealing ring is provided between the hanging ring and the conical surface.

9. The drilling fluid filter for preventing abrasion and cavitation of the inner wall of the drill pipe for directional drilling according to claim 1, 2, 5, 7 or 8, characterized in that The inner tube is made of anti-abrasion material and the filter holes are punched by laser.

10. The drilling fluid filter for preventing abrasion and cavitation of the inner wall of the drill pipe for directional drilling according to claim 6, characterized in that The inner tube is made of anti-abrasion material and the filter holes are punched by laser.

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