Anti-corrosion oil casing coupling

Abstract

The utility model relates to the technical field of oil casing couplings, in particular to an anti-corrosion oil casing coupling which comprises a coupling body, a drill rod and an oil casing are arranged at the two ends of the coupling body respectively, the coupling body is composed of a coupling pipe body, a first connecting column and a second connecting column, and a first annular clamping groove and a second annular clamping groove are formed in the coupling pipe body. A first external thread is arranged on the first connecting column, a second external thread is arranged on the second connecting column, a first sealing sleeve and a first annular block are arranged at the end, facing the first connecting column, of the drill rod, a second sealing sleeve and a second annular block are arranged at the end, facing the second connecting column, of the oil sleeve, and a corrosion-resistant coating is arranged in the inner wall of the coupling pipe body. According to the oil casing coupling, the situation that slurry drilling fluid permeates into the connecting part of the oil casing and the drill rod is avoided, then the situation that the threaded connecting part is corroded is avoided, the permeation resistance and corrosion resistance of the connecting part of the oil casing coupling are effectively improved, and the corrosion resistance of the inner wall face of the oil casing coupling is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of oil casing couplings, in particular to an anti-corrosion oil casing coupling. Background Art

[0002] Oil casing couplings are steel pipe connectors used in oil and gas wells in the petroleum and natural gas industry, mainly used to connect oil casing and drill pipe.

[0003] During the drilling process, the casing and tubing couplings transmit torque, allowing the drill pipe to rotate and break the rock.

[0004] During specific installation, one end of the oil casing coupling is installed to connect the oil casing, and the other end is installed to connect the drill pipe.

[0005] At present, in the existing oil casing coupling, when drilling for rock breaking through a drill pipe, there will be mud drilling fluid. The mud drilling fluid is a high-density liquid composed of water, clay, chemical additives and salt, which has a certain corrosiveness. Although the outer wall surface of the oil casing coupling has an anti-corrosion effect, the mud drilling fluid will penetrate into the connection part of the oil casing and the drill pipe, and then corrode the threaded connection part, which greatly reduces the anti-penetration and corrosion resistance of the connection part of the oil casing coupling.

[0006] In addition, the inner wall surface of the oil casing coupling itself has low corrosion resistance, which will greatly reduce the service life of the oil casing coupling itself.

[0007] The above problems are widespread and urgently need to be improved. Utility Model Content

[0008] The utility model aims to solve the above-mentioned shortcomings in the prior art and proposes an anti-corrosion oil casing coupling.

[0009] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0010] A corrosion-resistant oil casing coupling is designed, comprising a coupling body, wherein a drill pipe and an oil casing are respectively arranged at two ends of the coupling body, the coupling body is composed of a coupling pipe body, a first connecting column and a second connecting column, the coupling pipe body is provided with a first annular groove and a second annular groove, the first connecting column is provided with a first external thread, the second connecting column is provided with a second external thread, a first sealing sleeve and a first annular block are arranged at one end of the drill pipe facing the first connecting column, a second sealing sleeve and a second annular block are arranged at one end of the oil casing facing the second connecting column, and a corrosion-resistant coating is arranged on the inner wall of the coupling pipe body.

[0011] Furthermore, the interior of the coupling pipe body is a hollow cavity, the corrosion-resistant coating is evenly coated along the inner wall surface of the hollow cavity of the coupling pipe body, the corrosion-resistant coating is a Teflon coating, and the thickness of the corrosion-resistant coating is fifty to sixty microns.

[0012] Furthermore, the first connecting column is arranged at the left end of the coupling pipe body, and the second connecting column is arranged at the right end of the coupling pipe body. The first connecting column is threadedly connected to the drill pipe through a first external thread, and the second connecting column is threadedly connected to the oil casing through a second external thread.

[0013] Furthermore, the first annular groove and the first annular block are extruded and plugged, and the second annular groove and the second annular block are extruded and plugged.

[0014] Furthermore, the first annular block and the second annular block are both made of highly elastic vulcanized rubber and have a ring-shaped side cross-section. The first annular block is arranged on the inner side of the first sealing sleeve, and the second annular block is arranged on the inner side of the second sealing sleeve.

[0015] Furthermore, the first sealing sleeve is extruded and sleeved with the outer wall surface of the left end of the coupling pipe body, and the second sealing sleeve is extruded and sleeved with the outer wall surface of the right end of the coupling pipe body.

[0016] Furthermore, the first sealing sleeve and the second sealing sleeve are both made of FKM fluororubber.

[0017] The utility model provides an anti-corrosion oil casing coupling, which has the following beneficial effects:

[0018] 1. The utility model provides a first annular groove and a second annular groove structure on the coupling body, and provides a matching first sealing sleeve and a first annular block structure on the drill pipe, and simultaneously provides a matching second sealing sleeve and a second annular block structure on the oil casing. When the overall threaded connection is installed, the inner annular extrusion seal is achieved, and at the same time, the outer wall surface of the coupling body is subjected to overall extrusion sleeve sealing, so as to prevent mud drilling fluid from penetrating into the connection part of the oil casing and the drill pipe, thereby preventing the situation that the threaded connection part will be corroded, and effectively improving the anti-penetration and corrosion resistance of the connection part of the oil casing coupling.

[0019] 2. The utility model provides a corrosion-resistant coating structure on the inner wall surface of the coupling body, thereby improving the corrosion resistance of the inner wall surface of the oil casing coupling itself, thereby greatly improving the service life of the oil casing coupling itself. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is an exploded view of the overall structure of the utility model from the first perspective;

[0021] Figure 2 It is an exploded view of the overall structure of the utility model from a second perspective;

[0022] Figure 3 For the utility model Figure 1 A three-dimensional schematic diagram of the middle coupling body;

[0023] Figure 4 For the utility model Figure 1 A three-dimensional schematic diagram of the state where the drill pipe and the oil casing have been connected and installed;

[0024] Figure 5 For the utility model Figure 4 A front view of the overall structure;

[0025] Figure 6 For the utility model Figure 5 A partial enlarged view of the middle Z.

[0026] In the figure: 1 coupling body; 2 coupling pipe body; 21 first annular groove; 22 second annular groove; 3 first connecting column; 31 first external thread; 4 second connecting column; 41 second external thread; 5 drill pipe; 51 first sealing sleeve; 52 first annular block; 6 oil casing; 61 second sealing sleeve; 62 second annular block; 7 corrosion-resistant coating. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0028] Reference Figure 1-6 A corrosion-resistant oil casing coupling comprises a coupling body 1, wherein a drill pipe 5 and an oil casing 6 are respectively arranged at both ends of the coupling body 1, the coupling body 1 is composed of a coupling pipe body 2, a first connecting column 3, and a second connecting column 4, the coupling pipe body 2 is provided with a first annular groove 21 and a second annular groove 22, the first connecting column 3 is provided with a first external thread 31, the second connecting column 4 is provided with a second external thread 41, the drill pipe 5 is provided with a first sealing sleeve 51 and a first annular block 52 at one end facing the first connecting column 3, the oil casing 6 is provided with a second sealing sleeve 61 and a second annular block 62 at one end facing the second connecting column 4, the inner wall of the coupling pipe body 2 is provided with a corrosion-resistant coating 7, the coupling body 1 is an oil casing coupling, which is a prior art, and the drill pipe 5 and the oil casing 6 are also prior art, and some existing structures are not drawn and marked, and no further description is required.

[0029] In detail, the interior of the coupling pipe body 2 is a hollow cavity, and the corrosion-resistant coating 7 is evenly coated along the inner wall of the hollow cavity of the coupling pipe body 2. The corrosion-resistant coating 7 is a Teflon coating, and the thickness of the corrosion-resistant coating 7 is fifty to sixty microns. The Teflon coating has excellent corrosion resistance, and its body is wear-resistant and durable.

[0030] Furthermore, the first connecting column 3 is arranged at the left end of the coupling pipe body 2, and the second connecting column 4 is arranged at the right end of the coupling pipe body 2. The first connecting column 3 is threadedly connected to the drill pipe 5 through the first external thread 31, and the second connecting column 4 is threadedly connected to the oil casing 6 through the second external thread 41.

[0031] Furthermore, the first annular groove 21 and the first annular block 52 are squeezed and plugged, and the second annular groove 22 and the second annular block 62 are squeezed and plugged, so that the inner sides of the two ends of the butt collar pipe body 2 are squeezed and sealed to achieve an inner layer of anti-corrosion effect.

[0032] In more detail, the first annular block 52 and the second annular block 62 are both made of highly elastic vulcanized rubber and have a ring-shaped side cross-section. The first annular block 52 is arranged on the inner side of the first sealing sleeve 51, and the second annular block 62 is arranged on the inner side of the second sealing sleeve 61. When the first annular block 52 and the second annular block 62 are respectively squeezed and inserted into the matching first annular groove 21 and the second annular groove 22, the first annular block 52 and the second annular block 62 themselves will be squeezed and deformed to generate a lateral rebound force, which can enhance the anti-loosening effect of the first external thread 31 and the second external thread 41.

[0033] The high-elastic vulcanized rubber material has high elastic sealing properties, and at the same time has excellent corrosion resistance and is durable.

[0034] In general, the first sealing sleeve 51 is squeezed and sleeved with the outer wall of the left end of the coupling pipe body 2, and the second sealing sleeve 61 is squeezed and sleeved with the outer wall of the right end of the coupling pipe body 2, so that the outer walls of the left and right sides of the coupling pipe body 2 are squeezed and sleeved as a whole to prevent mud drilling fluid from penetrating into the connection parts of the oil casing and the drill pipe and causing corrosion to the threaded connection parts, thereby achieving an anti-corrosion effect of the outer layer.

[0035] Finally, the first sealing sleeve 51 and the second sealing sleeve 61 are both made of FKM fluororubber material. FKM fluororubber material has excellent corrosion resistance, and its body has high elastic sealing performance, which improves corrosion resistance.

[0036] Working method: After the drill pipe 5 is threadedly connected and installed with the first external thread 31 on the first connecting column 3 through the preset internal thread, the first annular groove 21 will be squeezed and plugged with the first annular block 52, and at the same time, the first sealing sleeve 51 will squeeze and sleeve the left end outer wall surface of the coupling pipe body 2 as a whole, and then the oil casing 6 is threadedly connected and installed with the second external thread 41 on the second connecting column 4 through the preset internal thread. At this time, the second annular groove 22 will be squeezed and plugged with the second annular block 62, and at the same time, the second sealing sleeve 61 will squeeze and sleeve the right end outer wall surface of the coupling pipe body 2 as a whole, so as to achieve the inner annular extrusion sealing, and at the same time, the left and right outer wall surfaces of the coupling pipe body 2 are squeezed and sleeved as a whole to prevent mud drilling fluid from penetrating into the connection parts of the oil casing and the drill pipe, thereby avoiding the situation of corroding the threaded connection parts, and effectively improving the anti-penetration and corrosion resistance of the connection parts of the oil casing coupling.

[0037] In addition, by providing the corrosion-resistant coating 7 structure on the inner wall surface of the coupling body 2, the corrosion resistance of the inner wall surface of the oil casing coupling itself is improved, thereby greatly improving the service life of the oil casing coupling itself.

[0038] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An anti-corrosion oil casing coupling, comprising a coupling body (1), characterized in that: A drill pipe (5) and an oil casing (6) are respectively arranged at the two ends of the coupling body (1). The coupling body (1) is composed of a coupling pipe body (2), a first connecting column (3), and a second connecting column (4). The coupling pipe body (2) is provided with a first annular groove (21) and a second annular groove (22). The first connecting column (3) is provided with a first external thread (31), and the second connecting column (4) is provided with a second external thread (41). The end of the drill pipe (5) facing the first connecting column (3) is provided with a first sealing sleeve (51) and a first annular block (52), and the end of the oil casing (6) facing the second connecting column (4) is provided with a second sealing sleeve (61) and a second annular block (62). The inner wall of the coupling pipe body (2) is provided with a corrosion-resistant coating (7).

2. The anti-corrosion oil casing coupling according to claim 1, characterized in that: The interior of the coupling pipe body (2) is a hollow cavity, and the corrosion-resistant coating (7) is evenly coated along the inner wall surface of the hollow cavity of the coupling pipe body (2). The corrosion-resistant coating (7) is a Teflon coating, and the thickness of the corrosion-resistant coating (7) is fifty to sixty microns.

3. The anti-corrosion oil casing coupling according to claim 1, characterized in that: The first connecting column (3) is arranged at the left end of the coupling pipe body (2), and the second connecting column (4) is arranged at the right end of the coupling pipe body (2). The first connecting column (3) is threadedly connected to the drill pipe (5) through a first external thread (31), and the second connecting column (4) is threadedly connected to the oil casing (6) through a second external thread (41).

4. The anti-corrosion oil casing coupling according to claim 1, characterized in that: The first annular groove (21) and the first annular block (52) are extruded and plugged together, and the second annular groove (22) and the second annular block (62) are extruded and plugged together.

5. The corrosion-resistant oil casing coupling according to claim 1, characterized in that: The first annular block (52) and the second annular block (62) are both made of highly elastic vulcanized rubber and have a ring-shaped side cross-section. The first annular block (52) is arranged on the inner side of the first sealing sleeve (51), and the second annular block (62) is arranged on the inner side of the second sealing sleeve (61).

6. The corrosion-resistant oil casing coupling according to claim 1, characterized in that: The first sealing sleeve (51) is extruded and sleeved with the outer wall surface of the left end of the coupling pipe body (2), and the second sealing sleeve (61) is extruded and sleeved with the outer wall surface of the right end of the coupling pipe body (2).

7. The corrosion-resistant oil casing coupling according to claim 1, characterized in that: The first sealing sleeve (51) and the second sealing sleeve (61) are both made of FKM fluororubber.

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