Azimuth gamma measurement method and device

Abstract

The present invention provides an azimuth gamma measurement method and device, the method comprising: obtaining the measured value of the earth's gravity field component measured by a gravity accelerometer; obtaining the reverse measured value of the earth's gravity field component measured by a reverse acceleration sensor; wherein the reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer; and obtaining the sensitive value of the earth's gravity field component according to the measured value of the earth's gravity field component and the reverse measured value of the earth's gravity field component. Compared with the prior art, it is not necessary to measure the radius of the gravity accelerometer and the rotation center and the drill speed, thereby being able to remove the error caused by the uneven drill speed and improve the measurement accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of drilling, and in particular to an azimuth gamma measurement method and device. Background Art

[0002] Conventional natural gamma measurement while drilling systems lack directionality and cannot accurately determine whether the current wellbore trajectory enters / exits the reservoir from the bottom or top, and cannot provide an accurate basis for adjusting the next trajectory. The azimuth gamma measurement while drilling system can distinguish whether the wellbore is at the top or bottom of the reservoir based on the azimuth measurement curve shape, and can use the azimuth gamma curve shape and wellbore trajectory geometric parameters to calculate the reservoir inclination and reservoir thickness, thereby providing a more accurate basis for adjusting the wellbore trajectory and improving the reservoir encounter rate.

[0003] The existing azimuth gamma measurement method generally measures the radius between the acceleration sensor and the rotation center, and then corrects the deviation caused by the rotational centrifugal force through the real-time measurement of the rotation speed. However, in actual operations, it is easily affected by factors such as uneven drilling speed, which seriously reduces the calculation accuracy. Summary of the invention

[0004] An embodiment of the present invention provides an azimuth gamma measurement method for avoiding errors caused by uneven rotation speed of a drilling tool. The method comprises:

[0005] Obtaining the measured values ​​of the components of the earth's gravity field measured by the gravity accelerometer;

[0006] Obtaining a reverse measurement value of the earth's gravity field component measured by a reverse acceleration sensor; the reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer;

[0007] The sensitive value of the earth's gravity field component is obtained according to the measured value of the earth's gravity field component and the reverse measured value of the earth's gravity field component.

[0008] The embodiment of the present invention further provides an azimuth gamma measurement device for avoiding errors caused by uneven rotation speed of a drilling tool, the device comprising:

[0009] The earth gravity field component measurement value acquisition module is used to obtain the earth gravity field component measurement value measured by the gravity accelerometer;

[0010] The reverse measurement value acquisition module of the earth's gravity field component is used to acquire the reverse measurement value of the earth's gravity field component measured by the reverse acceleration sensor; the reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer;

[0011] The earth gravity field component sensitivity value determination module is used to obtain the earth gravity field component sensitivity value according to the earth gravity field component measurement value and the reverse measurement value of the earth gravity field component.

[0012] An embodiment of the present invention further provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned azimuth gamma measurement method when executing the computer program.

[0013] An embodiment of the present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program for executing the above-mentioned azimuth gamma measurement method.

[0014] In the embodiment of the present invention, the measured value of the earth's gravity field component measured by the gravity accelerometer is obtained; the reverse measured value of the earth's gravity field component measured by the reverse acceleration sensor is obtained; wherein the reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer; according to the measured value of the earth's gravity field component and the reverse measured value of the earth's gravity field component, the sensitive value of the earth's gravity field component is obtained. Since the reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer, the obtained measured value consists of two parts, one is the sensitive value of the earth's gravity field component, and the other is the centripetal acceleration value caused by the rotational inertia. These two parts of the value and the two parts of the measured value contained in the measured value obtained by the gravity accelerometer, one is the same size and the same direction, and the other is the same size and opposite direction. Through the difference or sum operation, the deviation caused by the rotational inertia can be removed, so that only the sensitive value of the earth's gravity field component is retained. Compared with the prior art, it is not necessary to measure the radius of the gravity accelerometer and the rotation center and the drilling speed, so that the error caused by the uneven drilling speed can be removed, and the measurement accuracy is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0016] Figure 1 Schematic diagram of the azimuth gamma measurement method in an embodiment of the present invention.

[0017] Figure 2 Schematic diagram of an example of measurement deviation caused by rotational inertia in an embodiment of the present invention.

[0018] Figure 3 It is a schematic diagram of the principle of automatically eliminating the rotational inertia deviation in a specific embodiment of the present invention.

[0019] Figure 4 Schematic diagram of an azimuth gamma measurement device in an embodiment of the present invention.

[0020] Figure 5 Schematic diagram of an azimuth gamma measurement device in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] The embodiment of the present invention provides an azimuth gamma measurement method to avoid the error caused by uneven drilling speed. Figure 1 As shown, the method includes:

[0023] Step 101: obtaining the measured values ​​of the earth's gravity field components measured by the gravity accelerometer;

[0024] Step 102: Obtaining a reverse measurement value of the earth's gravity field component measured by a reverse acceleration sensor; wherein the reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer;

[0025] Step 103: Obtain the sensitivity value of the earth's gravity field component according to the measured value of the earth's gravity field component and the reverse measured value of the earth's gravity field component.

[0026] Depend on Figure 1 It can be known from the process shown that in the embodiment of the present invention, by obtaining the measured value of the earth's gravity field component measured by the gravity accelerometer; obtaining the reverse measured value of the earth's gravity field component measured by the reverse acceleration sensor; wherein the reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer; according to the measured value of the earth's gravity field component and the reverse measured value of the earth's gravity field component, the sensitive value of the earth's gravity field component is obtained. Since the reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer, the obtained measured value consists of two parts, one is the sensitive value of the earth's gravity field component, and the other is the centripetal acceleration value caused by the rotational inertia. These two parts of the value and the two parts of the measured value contained in the measured value obtained by the gravity accelerometer, one is the same size and the same direction, and the other is the same size and opposite direction. Through the difference or sum operation, the deviation caused by the rotational inertia can be removed, so that only the sensitive value of the earth's gravity field component is retained. Compared with the prior art, it is not necessary to measure the radius of the gravity accelerometer and the rotation center and the drilling speed, so that the error caused by the uneven drilling speed can be removed, and the measurement accuracy is improved.

[0027] In the specific implementation, first obtain the measured values ​​of the earth's gravity field components measured by the gravity accelerometer. The existing measurement while drilling system generally includes three gravity accelerometers and three magnetometers installed on the three basic axes of the drilling tool. Among them, the gravity accelerometer measures the gravity field components of the three axes, and the magnetometer measures the geomagnetic field components. Figure 2 As shown in the figure, due to the existence of rotational inertia, the measurement value of the gravity accelerometer will be offset, from 0 as the center to both ends. When the measurement direction of the gravity accelerometer is the same as the direction of the rotation center, a positive offset will be generated. The farther the gravity accelerometer is from the rotation center and the greater the rotation speed, the greater the offset will be. The offset is often much larger than the sensitive value of the earth's gravity field component. At the same time, in actual work, the rotation of the drill string is usually uneven, and this offset will fluctuate continuously, making it difficult to remove the offset.

[0028] The applicant discovered that an acceleration sensor opposite to the gravity accelerometer is installed at a 180-degree position of the drill bit. The measurement value of the reverse acceleration sensor consists of two parts, one is the measurement value caused by the attitude of the sensitive earth's gravity field, and the other is the centripetal acceleration value caused by the rotational inertia. These two parts are the same as the two parts contained in the measurement value of the gravity accelerometer, one of which is the same size and direction, and the other is the same size and opposite direction. Through phase difference or phase sum operation, the deviation caused by the rotational inertia can be removed, and the sensitive value of the earth's gravity component can be retained, thereby obtaining an accurate attitude angle.

[0029] After obtaining the measured value of the earth's gravity field component measured by the gravity accelerometer, the reverse measured value of the earth's gravity field component measured by the reverse acceleration sensor is obtained. The reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer and is installed at a 180° position on the drill string where the gravity accelerometer is located.

[0030] After obtaining the measured value of the earth gravity field component and the reverse measured value of the earth gravity field component, the earth gravity field component sensitivity value is obtained according to the measured value of the earth gravity field component and the reverse measured value of the earth gravity field component. The specific process includes: adding the measured value of the earth gravity field component and the reverse measured value of the earth gravity field component, taking the average value to obtain the earth gravity field component sensitivity value.

[0031] like Figure 3The figure shows the principle diagram of automatically eliminating the rotational inertia deviation in a specific embodiment of the present invention. y1(x) corresponds to the positive offset of the measured value of the gravity accelerometer caused by the rotational inertia. At the 180° position of the drill string where the gravity accelerometer is located, another acceleration sensor is installed in the opposite direction. The rotational inertia will cause the measured value of the reverse acceleration sensor to produce an offset of the opposite direction and equal magnitude, and its measurement curve is y2(x). Let y(x) = (y1(x) + y2(x)) / 2, then y(x) is the curve with the rotational inertia deviation removed, corresponding to the sensitive value of the earth's gravity field component under different postures.

[0032] In the azimuth gamma measurement method of the specific embodiment, Figure 1 On the basis of

[0033] Determine the attitude angle based on the sensitive value of the earth's gravity field component.

[0034] In specific implementation, during the process of the attitude change of the measured object, the sensitive value of the earth's gravity field component obtained according to the gravity accelerometer measurement value when the direction is consistent with the earth's gravity field is AX, and the sensitive value of the earth's gravity field component obtained according to the gravity accelerometer measurement value perpendicular to the earth's gravity field direction is AY. Then, the calculation formula of the attitude rotation angle H_TF of the measured object at any time is as follows:

[0035] If AX=0, then set AX=0.00001

[0036]

[0037] Based on the same inventive concept, the embodiment of the present invention further provides an azimuth gamma measurement device. Since the principle of the problem solved by the azimuth gamma measurement device is similar to that of the azimuth gamma measurement method, the implementation of the azimuth gamma measurement device can refer to the implementation of the azimuth gamma measurement method, and the repeated parts will not be repeated. The specific structure is as follows: Figure 4 As shown:

[0038] The earth gravity field component measurement value acquisition module 401 is used to acquire the earth gravity field component measurement value measured by the gravity accelerometer;

[0039] The reverse measurement value acquisition module 402 of the earth's gravity field component is used to acquire the reverse measurement value of the earth's gravity field component measured by the reverse acceleration sensor; wherein the reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer;

[0040] The earth gravity field component sensitivity value determination module 403 is used to obtain the earth gravity field component sensitivity value according to the earth gravity field component measurement value and the reverse measurement value of the earth gravity field component.

[0041] In a specific embodiment, the reverse acceleration sensor is installed at a position 180° of the drill string where the gravity accelerometer is located.

[0042] In specific implementation, the earth gravity field component sensitivity value determination module 403 is specifically used to:

[0043] After adding the measured value of the earth's gravity field component and the reverse measured value of the earth's gravity field component, the average value is taken to obtain the sensitivity value of the earth's gravity field component.

[0044] In a specific embodiment, an azimuth gamma measurement device is also provided. Figure 5 As shown, in Figure 4 Based on the above, it also includes: a posture angle determination module 501, which is used to:

[0045] Determine the attitude angle based on the sensitive value of the earth's gravity field component.

[0046] An embodiment of the present invention further provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned azimuth gamma measurement method when executing the computer program.

[0047] An embodiment of the present invention further provides a computer-readable storage medium storing a computer program for executing the above-mentioned azimuth gamma measurement method.

[0048] In summary, the azimuth gamma measurement method and device provided by the embodiments of the present invention have the following advantages:

[0049] By obtaining the measured value of the earth's gravity field component measured by the gravity accelerometer; obtaining the reverse measured value of the earth's gravity field component measured by the reverse acceleration sensor; wherein the reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer; according to the measured value of the earth's gravity field component and the reverse measured value of the earth's gravity field component, the sensitive value of the earth's gravity field component is obtained. Since the reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer, the obtained measured value consists of two parts, one is the sensitive value of the earth's gravity field component, and the other is the centripetal acceleration value caused by the rotational inertia. These two parts of the value and the two parts of the measured value obtained by the gravity accelerometer are included in the measurement value, one is the same size and direction, and the other is the same size and opposite direction. Through phase difference or phase sum operation, the deviation caused by the rotational inertia can be removed, so that only the sensitive value of the earth's gravity field component is retained. Compared with the prior art, it is not necessary to measure the radius of the gravity accelerometer and the rotation center and the drilling tool speed, so that the error caused by the uneven drilling tool speed can be removed, and the measurement accuracy is improved.

[0050] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, devices, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0051] The present invention is described with reference to flowcharts and / or block diagrams of methods, apparatuses, and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as a combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0052] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0053] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the embodiments of the present invention may have various modifications and variations. 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 method for measuring azimuth gamma, characterized in that: include: Obtaining the measured values ​​of the components of the earth's gravity field measured by the gravity accelerometer; Obtaining the reverse measurement value of the earth's gravity field component measured by the reverse acceleration sensor; The reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer; Obtaining a sensitivity value of the earth's gravity field component according to the measured value of the earth's gravity field component and the reverse measured value of the earth's gravity field component; The reverse acceleration sensor is installed at a 180° position of the drill string where the gravity accelerometer is located; Obtaining the sensitive value of the earth's gravity field component according to the measured value of the earth's gravity field component and the reverse measured value of the earth's gravity field component, including: After adding the measured value of the earth's gravity field component and the reverse measured value of the earth's gravity field component, taking the average value to obtain the earth's gravity field component sensitivity value; Determine the attitude angle according to the sensitive value of the earth's gravity field component; The sensitive value of the earth's gravity field component obtained from the gravity accelerometer measurement value when the direction is consistent with the earth's gravity field is AX. At this time, the sensitive value of the earth's gravity field component obtained from the gravity accelerometer measurement value perpendicular to the earth's gravity field is AY. The calculation formula for the attitude angle H_TF of the measured object at any time is as follows: If AX=0, then set AX=0.00001 2. An azimuth gamma measurement device, characterized in that: The method according to claim 1, wherein the device comprises: The earth gravity field component measurement value acquisition module is used to obtain the earth gravity field component measurement value measured by the gravity accelerometer; The reverse measurement value acquisition module of the earth's gravity field component is used to acquire the reverse measurement value of the earth's gravity field component measured by the reverse acceleration sensor; the reverse acceleration sensor is installed in the opposite direction to the gravity accelerometer; The earth gravity field component sensitivity value determination module is used to obtain the earth gravity field component sensitivity value according to the earth gravity field component measurement value and the reverse measurement value of the earth gravity field component.

3. The device according to claim 2, characterized in that The reverse acceleration sensor is installed at a 180° position of the drill string where the gravity accelerometer is located.

4. The device according to claim 2, characterized in that The earth gravity field component sensitivity value determination module is specifically used for: After adding the measured value of the earth's gravity field component and the reverse measured value of the earth's gravity field component, an average value is taken to obtain the earth's gravity field component sensitivity value.

5. The device according to claim 2, characterized in that Also includes: The attitude angle determination module is used to: Determine the attitude angle based on the sensitive value of the earth's gravity field component.

6. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method of claim 1 is implemented.

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program for executing the method of claim 1.

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