Well logging while drilling device

Abstract

The invention belongs to the technical field of logging instruments, and particularly relates to a logging-while-drilling device. The logging-while-drilling device comprises a shell, the shell is detachably arranged on a downhole tool, and at least one antenna is arranged in the shell; a plurality of magnetic bars are uniformly arranged in the shell along the circumferential direction, and the central axis of each magnetic bar is parallel to the central axis of the shell; and the measuring circuit is arranged in the underground tool in a sealing manner and is connected with the antenna. The operation and maintenance difficulty of the antenna can be reduced, and installation is convenient.

Description

Technical Field

[0001] The invention belongs to the technical field of well logging instruments, and in particular relates to a well logging while drilling device. Background Art

[0002] With the improvement of oilfield exploration and development, electromagnetic wave resistivity instruments while drilling are increasingly used in formation evaluation and geological guidance.

[0003] The amplitude resistivity and phase resistivity used in formation evaluation are obtained by converting the amplitude ratio and phase difference of the electromagnetic wave signals of two receiving antennas. Existing electromagnetic wave resistivity instruments while drilling generally use multiple transmitting and two receiving antennas to measure formation resistivity. For example, Schlumberger's MCR instrument uses two transmitting and two receiving antennas, and Halliburton's EWR-phase4 instrument uses four transmitting and two receiving antennas. Both the transmitting antenna and the receiving antenna are embedded in the drill collar.

[0004] In actual application, it is found that embedding the antenna into the drill collar can improve the reliability of the instrument, but for field application engineers, the maintenance cost of the instrument after the well is completed is very high. When the antenna is broken or the antenna seal is damaged, the instrument needs to be sent to the manufacturing base for antenna stripping and instrument recalibration testing, which increases the operation and maintenance cost. Therefore, it is urgent to improve the design and installation method of the antenna. Summary of the invention

[0005] In view of the technical problems described above, the present invention aims to provide a logging while drilling device, which can reduce the difficulty of operation and maintenance of the antenna and facilitate installation.

[0006] According to the present invention, there is provided a logging while drilling device, comprising:

[0007] A shell, wherein the shell is arranged in a semicircular shape, and two shells are buckled with each other so as to be detachably arranged on the downhole tool;

[0008] An antenna is arranged in the housing, the antenna comprises an axial antenna and a tilted antenna staggered in the housing, a first circuit and a second circuit adapted to each other are arranged on the axial antenna and the tilted antenna respectively, the axial antenna is adapted to the first circuit, the tilted antenna is adapted to the second circuit, the antenna and the adapted circuit are packaged together in the housing, no debugging is required, the antenna can be used immediately after being connected, and the use is convenient, the axial antenna is used for conventional electromagnetic wave resistivity measurement, and the tilted antenna is used for azimuthal electromagnetic wave resistivity measurement;

[0009] A pin and a socket that are adapted to each other are arranged between the contact surfaces of the two shells. After the pin and the socket are plugged into each other, the two shells are fixedly connected on the one hand, and on the other hand, the partial axial antennas and partial tilted antennas in the two shells are electrically connected respectively to form a complete axial antenna and a tilted antenna;

[0010] A plurality of magnetic bars are evenly arranged in the shell along the circumferential direction, and the central axis of the magnetic bars is parallel to the central axis of the shell;

[0011] A measuring circuit is sealed and arranged in the downhole tool and is connected to the axial antenna and the tilted antenna in a detachable manner.

[0012] In a preferred embodiment, a detector installation groove is provided on the downhole tool, and the housing is disposed in the detector installation groove.

[0013] In a preferred embodiment, a circuit installation groove is provided on the downhole tool, and the measuring circuit is sealed in the circuit installation groove.

[0014] In a preferred embodiment, a connecting line is provided inside the downhole tool between the detector installation slot and the circuit installation slot, one end of the connecting line is connected to the measuring circuit, and the other end is connected to the antenna.

[0015] In a preferred embodiment, a protective cover is provided outside the housing.

[0016] In a preferred embodiment, a plurality of gaps are evenly arranged on the protective cover along the circumferential direction.

[0017] In a preferred embodiment, both ends of the antenna extend from axial ends of the housing.

[0018] In a preferred embodiment, the axial antenna is arranged in a ring shape inside the shell, and the central axis of the ring formed by the axial antenna is parallel to the central axis of the shell.

[0019] In a preferred embodiment, the tilted antenna is arranged in a ring shape inside the housing, and a central axis of the ring formed by the tilted antenna is inclined to a central axis of the housing.

[0020] In a preferred embodiment, the connecting wire is detachably connected to the antenna.

[0021] Compared with the prior art, the advantages of the present application are as follows.

[0022] The present invention arranges the antenna in a cylindrical shell, and the shell is installed on the downhole tool in a conveniently disassembled manner. Once a problem occurs with the antenna or the sealant, the shell can be disassembled and replaced nearby, which greatly reduces the operation and maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be described below with reference to the accompanying drawings.

[0024] Figure 1 A schematic diagram showing an embodiment of a housing and an antenna therein according to the present invention;

[0025] Figure 2 A schematic diagram showing an embodiment in which the housing is combined into a tubular shape according to the present invention;

[0026] Figure 3 A schematic diagram showing the installation structure of the logging while drilling device according to the present invention is shown;

[0027] Figure 4 The installation flow chart of the logging while drilling device according to the present invention is shown.

[0028] In the figure: 100, logging while drilling device; 101, axial antenna; 102, tilted antenna; 103, magnetic rod; 104, first circuit; 105, second circuit; 106, shell; 107, first pin; 108, first jack; 109, second pin; 110, second jack; 111, third pin; 112, fourth pin; 113, fifth pin; 114, sixth pin; 115, partition surface; 301, protective cover; 302, gap; 303, non-magnetic drill collar; 304, detector mounting slot; 305, third jack; 306, fourth jack; 307, fifth jack; 308, sixth jack; 309, circuit mounting slot; 310, measuring circuit.

[0029] In the present application, all drawings are schematic drawings, which are only used to illustrate the principles of the present invention and are not drawn according to the actual scale. DETAILED DESCRIPTION

[0030] The present invention will be described below with reference to the accompanying drawings.

[0031] Figure 1 to Figure 3 The structure of the logging while drilling device 100 according to the present invention is shown. Figure 1 to Figure 3 As shown, the logging while drilling device 100 includes a housing 106, a magnetic rod 103 and a measuring circuit 310. The housing 106 can be detachably arranged on a downhole tool. In this embodiment, the downhole tool is a non-magnetic drill collar 303 as an example, that is, the housing 106 can be detachably arranged on the non-magnetic drill collar 303.

[0032] like Figure 1 and Figure 2 As shown, the housing 106 of this embodiment is configured as two semicircular structures, and the two semicircular housings 106 are interlocked to form a circular tube shape, so as to be sleeved on the non-magnetic drill collar 303. Figure 1 The structure in which two semicircular shells 106 are separated from each other is shown. Figure 2The structure is shown in which two semicircular shells 106 are buckled together to form a circular tube.

[0033] In this embodiment, the housing 106 is made of epoxy resin material, which can withstand high temperature and high pressure. At least one antenna is arranged in the housing 106, and the antenna is connected to the measurement circuit 310 to realize the function of measurement while drilling. It is easy to understand that the basic working principle of the antenna and the measurement circuit 310 is the existing technology and will not be repeated here.

[0034] Specifically, Figure 1 and Figure 2 As shown, two antennas are arranged in the housing 106, namely, an axial antenna 101 and a tilted antenna 102. The axial antenna 101 and the tilted antenna 102 are respectively provided with a first circuit 104 and a second circuit 105 matching therewith. The axial antenna 101 can be used to perform conventional electromagnetic wave resistivity measurement, and the tilted antenna 102 can be used to perform azimuthal electromagnetic wave resistivity measurement, which has a multi-purpose function. The axial antenna 101 and the tilted antenna 102 are both arranged in a circular ring shape and fixed inside the housing 106. Among them, the central axis of the circular ring formed by the axial antenna 101 is parallel to the central axis of the housing 106. Further, the central axis of the circular ring formed by the axial antenna 101 in this embodiment coincides with the central axis of the housing 106. The central axis of the circular ring formed by the tilted antenna 102 and the central axis of the housing 106 are inclined to each other. Further, the central axis of the circular ring formed by the tilted antenna 102 in this embodiment intersects with the central axis of the housing 106.

[0035] The two shells 106 of this embodiment are buckled together to form a complete circular tube, and the contact surface of the two shells 106 is the partition surface 115, and the plane where the partition surface 115 is located passes through the central axis of the shell 106. Since the two shells 106 need to be separated, the axial antenna 101 and the tilted antenna 102 are divided into two parts, which are respectively arranged in the two shells 106. When the two shells 106 are buckled together, that is, when the partition surfaces 115 of the two shells 106 are in contact with each other, the two parts of the axial antenna 101 and the tilted antenna 102 are connected to each other to form a complete axial antenna 101 and a tilted antenna 102 respectively.

[0036] That is, the axial antenna 101 is divided into two parts, which are arranged in two shells 106. Taking the axial antenna 101 in one of the shells 106 as an example, the shell 106 includes two partition surfaces 115, one end of the axial antenna 101 extends from one of the partition surfaces 115 of the shell 106 in the circumferential direction, and the other end of the axial antenna 101 enters the interior of the shell 106, extends along the circumferential direction of the shell 106 until it extends to the other partition surface 115 of the shell 106, and then extends along the radial direction of the shell 106 until it extends from the axial end of the shell 106. Furthermore, the parts of the axial antennas 101 of the two shells 106 that extend from the partition surface 115 are connected to each other in a detachable manner, thereby forming a complete axial antenna 101. Specifically, a first pin 107 is provided on the axial antenna 101 extending from the partition surface 115 of one of the shells 106, and a first socket 108 is provided on the axial antenna 101 extending from the partition surface 115 of the other shell 106. When the two shells 106 are buckled together, the first pin 107 is inserted into the first socket 108, which can be electrically connected and withstand high-voltage sealing, so that the two parts of the axial antenna 101 are connected to each other to form a complete axial antenna 101.

[0037] Similarly, the tilted antenna 102 is divided into two parts, which are arranged in two shells 106. Taking the tilted antenna 102 in one of the shells 106 as an example, the shell 106 includes two partition surfaces 115, one end of the tilted antenna 102 extends from one of the partition surfaces 115 of the shell 106 along the circumferential direction, and the other end of the tilted antenna 102 enters the interior of the shell 106, and extends along the circumferential direction of the shell 106 at a certain tilted angle until it extends to the other partition surface 115 of the shell 106, and then extends along the radial direction of the shell 106 until it extends from the axial end of the shell 106. Further, the parts of the tilted antennas 102 of the two shells 106 that extend from the partition surface 115 are connected to each other in a detachable manner, thereby forming a complete tilted antenna 102. Specifically, a second pin 109 is provided on the tilted antenna 102 extending from the partition surface 115 of one of the shells 106, and a second socket 110 is provided on the tilted antenna 102 extending from the partition surface 115 of the other shell 106. When the two shells 106 are buckled together, the second pin 109 is inserted into the second socket 110, which can be electrically connected and withstand high-voltage sealing, so that the two parts of the tilted antenna 102 are connected to each other to form a complete tilted antenna 102.

[0038] The two parts of the axial antenna 101 extending from the axial end of the housing 106 are respectively provided with a third pin 111 and a fourth pin 112. The two parts of the tilted antenna 102 extending from the axial end of the housing 106 are respectively provided with a fifth pin 113 and a sixth pin 114. Figure 2As shown, when the two housings 106 are buckled together, only the third pin 111 , the fourth pin 112 , the fifth pin 113 and the sixth pin 114 are exposed outside the housing 106 .

[0039] In a specific embodiment, the entire axial antenna 101 is a wire with high conductivity and small cross-sectional area. The vertical shell 106 is axially wound on the outside of the magnetic rod 103. When AC is passed, it will generate regular magnetic field signals, and can also sense the surrounding magnetic field changes and convert them into electric field signals. Therefore, the axial antenna 101 can be used as both a transmitting antenna and a receiving antenna. The first circuit 104 is composed of resistors and capacitors, which can adjust the impedance of the axial antenna 101. One end is connected to the axial antenna 101, and the other end is connected to the fourth pin 112.

[0040] In a specific embodiment, the entire tilted antenna 102 is a wire with high conductivity and small cross-sectional area, which is wound around the outer side of the magnetic rod 103 at an oblique angle to the axial direction of the housing 106, and can sense the surrounding magnetic field changes and convert them into electric field signals. Generally, the tilted antenna 102 is used as a receiving antenna. The second circuit 105 is composed of a resistor and a capacitor, which can adjust the impedance of the tilted antenna 102, one end of which is connected to the tilted antenna 102, and the other end is connected to the sixth pin 114.

[0041] A plurality of magnetic bars 103 are evenly arranged in the circumferential direction in the housing 106, and the central axis of the magnetic bars 103 is parallel to the central axis of the housing 106. In a specific embodiment, the magnetic bars 103 are cylindrical in shape, the length of the magnetic bars 103 is smaller than the length of the housing 106, the diameter of the magnetic bars 103 is smaller than the wall thickness of the housing 106, and a plurality of magnetic bars 103 are evenly spaced in the circumferential direction inside the housing 106, which can increase the magnetic field strength near the housing 106.

[0042] like Figure 3 As shown, a detector installation groove 304 is provided on the non-magnetic drill collar 303, and the housing 106 is provided in the detector installation groove 304. Specifically, the detector installation groove 304 is provided as an annular groove structure, which is adapted to the shape and size of the housing 106.

[0043] A circuit installation groove 309 is provided on the non-magnetic drill collar 303, and the measuring circuit 310 is sealed and arranged in the circuit installation groove 309. Specifically, the circuit installation groove 309 is set as a rectangular parallelepiped structure, which can accommodate the measuring circuit 310.

[0044] A connecting wire is provided inside the non-magnetic drill collar 303 between the detector mounting groove 304 and the circuit mounting groove 309, one end of the connecting wire is connected to the measuring circuit 310, and the other end is connected to the antenna. Specifically, in this embodiment, four connecting wires are provided, and the connecting wires are provided along the axis direction of the non-magnetic drill collar 303. The ends of the four connecting wires close to the detector mounting groove 304 are respectively provided with a third jack 305, a fourth jack 306, a fifth jack 307 and a sixth jack 308, and the other ends of the four connecting wires extend into the circuit mounting groove 309 and are connected to the measuring circuit 310.

[0045] Through this arrangement, after the housing 106 is installed in the detector installation slot 304, the exposed third pin 111, fourth pin 112, fifth pin 113 and sixth pin 114 can be respectively inserted into the third jack 305, fourth jack 306, fifth jack 307 and sixth jack 308 by plugging, and can be electrically connected and withstand high-pressure sealing, thereby achieving the purpose of quickly connecting the antenna in the housing 106 with the measurement circuit 310. The measurement circuit 310 transmits an alternating current signal to the axial antenna 101, and can also transmit the electromagnetic wave receiving signal of the tilted antenna 102 to the measurement circuit 310 for signal acquisition. At the same time, this arrangement can make the measurement circuit 310 and the housing 106 separately arranged, and the measurement circuit 310 can be arranged in the non-magnetic drill collar 303 in a sealed manner, while the housing 106 part is connected to the outside of the non-magnetic drill collar 303.

[0046] Furthermore, a protective cover 301 is provided on the outside of the shell 106. In the present embodiment, the protective cover 301 is also composed of two semicircular parts to form a complete circular tube. After the shell 106 is set in the detector mounting groove 304, the protective cover 301 is then sleeved on the outside of the shell 106, thereby protecting the shell 106.

[0047] Furthermore, a plurality of slits 302 are evenly arranged along the circumferential direction on the protective cover 301. The length direction of each slit 302 is parallel to the axial direction of the protective cover 301. The slits 302 can enhance the transmission intensity of the electromagnetic wave signal.

[0048] The present invention can perform conventional electromagnetic wave resistivity measurement using the axial antenna 101 and can perform azimuthal electromagnetic wave resistivity measurement using the tilted antenna 102, and has a multi-purpose function.

[0049] It should be noted that, although only one axial antenna 101 and one tilted antenna 102 are provided in this embodiment, the present invention is not limited to this configuration, and the number of axial antennas 101 and tilted antennas 102 can be adjusted according to actual conditions.

[0050] like Figure 4FIG. 1 is an installation flow of the logging while drilling device 100 .

[0051] S401: Process the detector installation groove 304 and the circuit installation groove 309 on the outer wall of the non-magnetic drill collar 303. The detector installation groove 304 does not need to be sealed and can be exposed to a high-pressure environment. The circuit installation groove 309 needs to be sealed, and the groove is in a low-pressure environment. At the same time, the protective cover 301 is processed and a gap 302 is opened on it to transmit electromagnetic wave signals.

[0052] S402: The third jack 305, the fourth jack 306, the fifth jack 307 and the sixth jack 308 are provided in the non-magnetic drill collar 303, allowing the wires to be threaded to electrically connect the detector installation slot 304 with the circuit installation slot 309. The measuring circuit 310 is installed in the circuit installation slot 309 and high-pressure sealing is performed.

[0053] S403: directly buckle the housing 106 into the detector installation slot 304, and insert the third pin 111, the fourth pin 112, the fifth pin 113 and the sixth pin 114 into the third jack 305, the fourth jack 306, the fifth jack 307 and the sixth jack 308 respectively, to block the high voltage of the detector installation slot 304 from being conducted to the circuit installation slot 309. The third jack 305, the fourth jack 306, the fifth jack 307 and the sixth jack 308 are all welded with wires, and are connected to the measuring circuit 310 through the wires.

[0054] S404: Cover the protective cover 301 on the housing 106, and fix the protective cover 301 on the non-magnetic drill collar 303 with screws, so as to fix the housing 106 in the detector installation slot 304.

[0055] S405: According to different source distances and spacings, several detector installation grooves 304 are processed on the non-magnetic drill collar 303, and the housing 106 is installed in the grooves, thus forming a logging while drilling instrument with multiple measurement functions.

[0056] The invention adopts a modular design method, and makes the logging while drilling device 100 into a circular tube. A variety of antenna structures and antenna impedance matching circuits (such as the axial antenna 101, the tilted antenna 102, the first circuit 104, and the second circuit 105 provided in this embodiment) can be prefabricated in the tube, which solves the problem of instrument antenna debugging, is easy to install, and can quickly form a logging while drilling instrument. The antenna of the logging while drilling instrument can be replaced and the instrument repaired on site, which is of great significance to the large-scale production of the instrument and the reduction of the instrument operation and maintenance cost.

[0057] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0058] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0059] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0060] Finally, it should be noted that the above is only a preferred embodiment of the present invention and does not constitute any limitation to the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for a person skilled in the art to modify the technical solutions described in the aforementioned embodiments or to replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A logging while drilling device, characterized in that: include: A housing (106), wherein the housing (106) is arranged in a semicircular shape, and two housings (106) are buckled with each other so as to be detachably arranged on the downhole tool; An antenna arranged in the housing (106), the antenna comprising an axial antenna (101) and a tilted antenna (102) arranged alternately in the housing (106), the axial antenna (101) and the tilted antenna (102) being respectively provided with a first circuit (104) and a second circuit (105) adapted to each other, the axial antenna (101) being used for conventional electromagnetic wave resistivity measurement, and the tilted antenna (102) being used for azimuthal electromagnetic wave resistivity measurement; A pin and a socket that are adapted to each other are arranged between the contact surfaces of the two shells (106); after the pin and the socket are plugged into each other, the two shells (106) are fixedly connected on the one hand, and the partial axial antenna (101) and the partial tilted antenna (102) in the two shells (106) are electrically connected on the other hand, so as to form a complete axial antenna (101) and a tilted antenna (102); A plurality of magnetic bars (103) are evenly arranged in the circumferential direction in the shell (106), and the central axis of the magnetic bars (103) is parallel to the central axis of the shell (106); A measuring circuit (310) is sealed and arranged in a downhole tool, and is connected to the axial antenna (101) and the tilted antenna (102) in a detachable manner.

2. The logging while drilling device according to claim 1, characterized in that: A detector installation groove (304) is provided on the downhole tool, and the housing (106) is arranged in the detector installation groove (304).

3. The logging while drilling device according to claim 2, characterized in that: A circuit installation groove (309) is provided on the downhole tool, and the measuring circuit (310) is sealed and arranged in the circuit installation groove (309).

4. The logging while drilling device according to claim 3, characterized in that: A connecting wire is arranged inside the downhole tool between the detector installation groove (304) and the circuit installation groove (309), one end of the connecting wire is connected to the measurement circuit (310), and the other end is connected to the antenna.

5. The logging while drilling device according to any one of claims 2 to 4, characterized in that: A protective cover (301) is arranged outside the housing (106).

6. The logging while drilling device according to claim 5, characterized in that: A plurality of gaps (302) are evenly arranged on the protective cover (301) along the circumferential direction.

7. The logging while drilling device according to any one of claims 1 to 4, characterized in that: Both ends of the antenna extend from axial ends of the housing (106).

8. The logging while drilling device according to any one of claims 1 to 4, characterized in that: The axial antenna (101) is arranged in a ring shape inside the housing (106), and the central axis of the ring formed by the axial antenna (101) is parallel to the central axis of the housing (106).

9. The logging while drilling device according to any one of claims 1 to 4, characterized in that: The tilted antenna (102) is arranged in a ring shape inside the housing (106), and the central axis of the ring formed by the tilted antenna (102) and the central axis of the housing (106) are inclined relative to each other.

10. The logging while drilling device according to claim 4, characterized in that: The connecting wire is connected to the antenna in a detachable manner.

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