A coring device with inclination measurement

Abstract

This utility model discloses a coring device capable of measuring inclination, relating to the field of drilling technology. The aforementioned coring device includes a core tube for connecting to a coring drill bit and drilling tools, used to collect rock samples from the formation inside the wellbore. It also includes several stabilizers, all installed on the core tube and evenly distributed along its axis. The stabilizers are used to position and fix the core tube, reducing its deviation and improving the accuracy of the rock samples. At least one of the stabilizers has a groove and a cover plate for sealing the groove. The cover plate is detachably installed on the stabilizer. The device also includes a measuring instrument, placed in the groove, used to measure the inclination data of the core tube. This reduces the construction steps of separate tripping and measuring inclination, saves drilling time, and lowers construction costs.

Description

Technical Field

[0001] This utility model relates to the field of drilling technology, and more specifically, to a device for measuring inclined coring. Background Technology

[0002] To obtain accurate formation lithology and fluid information, the oil drilling industry typically uses coring operations to obtain formation rock samples. Because the drill bit and tooling assemblies for coring differ significantly from those for full-scale drilling, the wellbore trajectory control becomes altered. The longer the coring operation, the more the trajectory may deviate from the design or expected trajectory. Since coring often involves operations such as ball dropping and pressure build-up, conventional measurement-while-drilling (MWD) instruments and other similar tools cannot be used for trajectory monitoring. Therefore, a method of coring first and then measuring the inclination is required, necessitating two drilling operations, resulting in high time costs and increased wellbore risks.

[0003] In conclusion, improving the convenience of drilling and coring operations is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0004] In view of this, the purpose of this utility model is to provide a core sampling device capable of measuring well inclination during the core sampling process, thereby reducing the construction steps of separate tripping and drilling for inclination measurement, saving drilling time, and reducing construction costs.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] A device for measuring oblique coring, comprising:

[0007] Core tube, used to connect to the core drill bit and drill string;

[0008] A plurality of centralizers are installed on the core tube and evenly distributed along the axis of the core tube. At least one of the centralizers is provided with a groove and a cover plate for closing the groove. The cover plate is detachably installed on the centralizer.

[0009] A measuring device is placed in a groove and used to measure the tilt data of the core tube.

[0010] Furthermore, the centralizer is a strip-shaped structure extending along the axis of the core-collecting cylinder, and the centralizer is detachably installed on the core-collecting cylinder.

[0011] Furthermore, the present invention provides guide portions on both sides of the centralizer along the axis of the core tube, the guide portions being used to reduce the resistance when the centralizer moves.

[0012] Furthermore, the straightener has an arc-shaped surface with an opening facing the core-collecting cylinder on the side away from the core-collecting cylinder.

[0013] Furthermore, in this invention, there are several measuring devices, and the number is the same as that of the centralizer. Each of the several measuring devices is installed on a corresponding centralizer.

[0014] Furthermore, this utility model also includes:

[0015] A protective shell, wherein a cavity is provided inside the protective shell, and the measuring instrument is detachably placed inside the cavity.

[0016] Furthermore, the measuring device is detachably installed within the cavity.

[0017] Furthermore, a sealing structure is provided between the cover plate and the straightener in this utility model.

[0018] Furthermore, the measuring device includes a storage module, a triaxial accelerometer, a power supply module, a signal amplification circuit, and a data processing circuit, all of which are electrically connected to the power supply module.

[0019] Furthermore, the measuring device further includes a clock module, which is electrically connected to the power supply module and the data processing circuit.

[0020] The inclined coring device provided by this utility model first connects the coring cylinder to the drill string. The drill string then moves the coring cylinder within the wellbore to complete the coring sampling. Before entering the wellbore, a measuring device is installed inside the groove of a stabilizer. Several stabilizers are installed on the coring cylinder and evenly distributed along its axis. The stabilizers are used to position and fix the coring cylinder, reducing its deviation and improving the accuracy of the rock sample. The measuring device installed in the stabilizer groove detects the position of the coring cylinder. Therefore, wellbore sampling and inclination measurement can be completed in one operation, enabling wellbore inclination measurement during coring and thus wellbore trajectory monitoring. This avoids situations where the wellbore trajectory deviates too far from the expected value during coring, thus reducing the need for separate tripping and inclination measurement, saving drilling time, and lowering construction costs. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0022] Figure 1This is a side view of the device provided by this utility model;

[0023] Figure 2 This is a top view of the structure of the device provided by this utility model;

[0024] Figure 3 This is a structural schematic diagram of the side cross-section of the device provided by this utility model;

[0025] Figure 4 This is a schematic diagram of the measuring instrument system provided by this utility model.

[0026] Figures 1-4 In the accompanying drawings, the reference numerals include:

[0027] 1. Core tube; 2. Centralizer; 3. Cover plate; 4. Measuring device; 5. Guide section; 6. Groove. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] The core of this invention is to provide a coring device capable of measuring well inclination during the coring process, thereby reducing the construction steps of separate tripping and tripping for inclination measurement, saving drilling time, and reducing construction costs.

[0030] Please refer to Figure 2 A coring device for measuring inclination includes a coring cylinder 1 for connection with a coring drill bit and drilling tools. Specifically, the coring cylinder 1 is a hollow cylinder structure used to take rock samples from the formation inside the wellbore. Therefore, a measuring device cannot be installed inside the coring cylinder 1. It also includes several stabilizers 2, which are all installed on the coring cylinder 1 and evenly distributed along the axis of the coring cylinder 1. The stabilizers 2 are used to position and fix the coring cylinder 1, reduce the deviation of the coring cylinder 1, and improve the accuracy of the rock samples. At least one of the stabilizers 2 has a groove 6 and a cover plate 3 for sealing the groove 6. The cover plate 3 is detachably installed on the stabilizer 2. It also includes a measuring device 4, which is placed in the groove 6 and used to measure the inclination data of the coring cylinder 1.

[0031] It should be noted that in this embodiment of the present invention, both ends of the core tube 1 are provided with connecting structures for connection with the drilling tool. This connecting device is a mature existing technology, so it will not be described in detail here.

[0032] Optionally, in some embodiments, the centralizer 2 can be customized according to construction needs. That is, the size or shape of the centralizer 2 can be designed and manufactured according to actual needs. While meeting the requirements for pre-embedding of the inclination measuring instrument, it does not affect the trajectory control effect and can better control the wellbore trajectory during the coring process.

[0033] Optionally, in some embodiments, the shape and size of the groove 6 are similar to those of the measuring device 4. Specifically, by placing the measuring device 4 in the groove 6 and sealing the groove 6 with the cover plate 3, the cover plate 3 and the groove 6 can support the measuring device 4 and reduce its vibration displacement.

[0034] Optionally, in some embodiments, the cover plate 3 is detachably installed on the centralizer 2 by bolts, or it can be detachably installed on the centralizer 2 by a snap-fit ​​mechanism.

[0035] Optionally, in some embodiments, before running the instrument into the well, the measuring instrument assembly is connected to the computer and the instrument is set up. The measurement start time can be estimated based on the well depth. Then, it is run into the well along with the coring tool. After drilling to the bottom of the well, the pump is started normally for coring. After coring is completed, the pump is stopped and the drill string is left still for 1 to 3 minutes. The time is recorded synchronously. Then, the drill string is pulled out normally. After the drill string is pulled to the surface, the measuring section is wiped clean with a towel or paper towel, especially the area near the cover plate 3. Then, the screws are loosened with a tool, the cover plate 3 is removed, the instrument is taken out, connected to the computer, and the data is read. By using the data corresponding to the recorded time, the well bottom inclination data can be detected, thereby realizing the monitoring of the coring well trajectory.

[0036] In use, the core sampler 1 is first connected to the drill string. The drill string then moves the core sampler 1 within the wellbore to complete the sampling process. Before entering the wellbore, the measuring device 4 is installed inside the groove 6 of the stabilizer 2. There are several stabilizers 2, all installed in the core sampler 1 and evenly distributed along its axis. The stabilizers 2 are used to position and fix the core sampler 1, reducing its deviation and improving the accuracy of the rock sample. The measuring device 4 installed in the groove 6 of the stabilizer 2 detects the position of the core sampler 1. Therefore, wellbore sampling and inclination measurement can be completed in one operation, enabling wellbore inclination measurement during the core sampling process. This allows for wellbore trajectory monitoring, preventing the wellbore trajectory from deviating too far from the expected value during core sampling, thus reducing the need for separate tripping and inclination measurement, saving drilling time, and lowering construction costs.

[0037] Please refer to Figure 1In some embodiments, the stabilizer 2 is a strip structure extending along the axis of the core tube 1. That is, the stabilizer 2 is a protrusion installed on the outer wall of the core tube 1. The core tube 1 is kept vertical by contacting the well wall with several stabilizers 2, i.e., coaxial with the wellbore. At the same time, the strip structure can increase the contact length and area between the stabilizer 2 and the well wall, thereby increasing the positioning function of the stabilizer 2 on the core tube 1 and ensuring the accuracy of sampling.

[0038] Optionally, in some embodiments, the centralizer 2 is detachably installed on the core barrel 1. The detachable method allows for quick replacement of centralizers 2 of different sizes, making it convenient for use in wells of different sizes.

[0039] In the above embodiment, the centralizer 2 is detachably installed on the core tube 1 by bolts. Specifically, at least two bolts are provided, one at the top and one at the bottom of the centralizer 2.

[0040] Optionally, in some embodiments, an adjusting component is also provided. The adjusting component is used to adjust the distance between the centralizer 2 and the core barrel 1, thereby enabling the centralizer 2 to be applicable to wellbores of different sizes, greatly increasing its versatility and reducing the cost of preparing centralizers 2 of different sizes. Specifically, the adjusting component is a bolt structure, and the adjusting component is rotatably connected to the centralizer 2. The axial position of the adjusting component and the centralizer 2 is fixed. Through the threaded connection between the adjusting component and the core barrel 1, the distance between the walls of the centralizer 2 and the core barrel 1 can be adjusted by turning the adjusting component.

[0041] In other embodiments, the adjusting member is a bolt and is threadedly connected to the centralizer 2. Specifically, the centralizer 2 is provided with a conical through hole, and the adjusting member is threadedly engaged with the bottom of the through hole. By extending the adjusting member out of the centralizer 2 by different lengths, and then tightening the screw that fixes the centralizer 2, the centralizer 2 can be fixed in different positions, thereby realizing the adjustment of the distance between the centralizer 2 and the core tube 1.

[0042] Please refer to Figure 1 In some embodiments, the stabilizer 2 is provided with guide parts 5 on both sides along the axis of the core tube 1. The guide parts 5 are used to reduce the resistance when the stabilizer 2 moves. That is, the guide parts 5 are used to guide the stabilizer 2 and the well wall, reduce its resistance, and thus facilitate the movement of the core tube 1 in the wellbore.

[0043] Optionally, in some embodiments, the guide portion 5 is a right-angled triangular structure, and the inclined surface of the guide portion 5 faces the side away from the core tube 1, and the guide portion 5 is smoothly connected to the centering device 2, thereby improving its guiding effect.

[0044] In other embodiments, the guide portion 5 has a conical structure, and the conical guide portion 5 is smoothly connected to the centralizer 2. The guide portion 5 with a pointed tip can further reduce the resistance when it contacts the well wall.

[0045] Optionally, in some embodiments, both the guide portion 5 and the stabilizer 2 are made of wear-resistant materials, and the guide portion 5 and the stabilizer 2 can be integrally molded.

[0046] Optionally, in some embodiments, in order to further improve the centering effect after the centralizer 2 contacts the well wall, the centralizer 2 is provided with an arc surface with an opening facing the core tube 1 on the side away from the core tube 1. The arc surface can reduce friction on the well wall, and at the same time, the arc surface can increase the fit between it and the well wall, thereby improving the centering effect of the centralizer 2.

[0047] Please refer to Figure 1 In some embodiments, there are several measuring devices 4, and the number is the same as that of the centralizer 2. Each of the several measuring devices 4 is installed on a corresponding centralizer 2. That is to say, multiple measuring devices 4 are used to collect downhole data simultaneously. This not only avoids the situation where data collection fails when a single measuring device 4 malfunctions, but also allows for the summarization, analysis, and averaging of the data collected by multiple measuring devices 4, thereby improving the accuracy of the collected data.

[0048] Optionally, in some embodiments, a protective shell is also included, with a cavity inside the protective shell. The measuring device 4 is detachably placed inside the cavity. That is, the protective shell is used to protect the measuring device 4 to prevent malfunction of the measuring device 4. At the same time, the protective shell seals the measuring device 4 to prevent drilling fluid from affecting the service life of the measuring device 4.

[0049] In the above embodiment, the protective shell has a cavity structure and an opening on one side. A lid is hinged to the opening, and the lid is closed by means of a snap fastener, a lock, or other structure. At the same time, a sealing ring is provided at the connection between the lid and the protective shell to increase the sealing effect and ensure effective sealing.

[0050] Optionally, in some embodiments, a complete seal can be achieved by immersing the sealant in the joint between the lid and the protective shell, and allowing the sealant to air dry.

[0051] In the above embodiments, the sealant can be a fast-drying adhesive, which is rapidly dried by ultraviolet irradiation.

[0052] Optionally, in some embodiments, a sealing structure is provided between the cover plate 3 and the stabilizer 2. The sealing structure further enhances the waterproof effect of the measuring device 4 and ensures the normal use of the measuring device 4.

[0053] In the above embodiment, the sealing structure includes a sealing ring. The sealing effect is achieved by the cover plate 3 pressing the sealing ring at the contact position between the cover plate 3 and the groove 6 of the stabilizer 2.

[0054] In the above embodiments, a toothed structure is also included. Specifically, the contact positions of the cover plate 3 and the groove 6 of the stabilizer 2 are provided with several corresponding toothed structures. When the cover plate 3 and the stabilizer 2 are engaged, not only can the positioning effect be achieved, but the sealing performance can also be further increased. That is to say, through at least a triple sealing structure, the measuring instrument 4 is ensured not to be contacted by drilling fluid, thus ensuring its service life.

[0055] Optionally, in some embodiments, the groove 6 or the cover plate 3 is provided with a clamping member for fixing the protective shell. Specifically, the clamping member is a rubber strip and is installed on the cover plate 3. By squeezing the protective shell with several rubber strips, its position inside the groove 6 is fixed. The rubber strip has good vibration absorption capacity, which further improves the shock resistance of the measuring instrument 4.

[0056] Please refer to Figure 1 In some embodiments, the measuring device 4 includes a storage module, a triaxial accelerometer, a power supply module, a signal amplification circuit, and a data processing circuit. The storage module, triaxial accelerometer, signal amplification circuit, and data processing circuit are all electrically connected to the power supply module. The power supply module provides power to the entire measuring device 4. The triaxial accelerometer is used to perform inclinometer measurement and store the collected data in the storage module. The signal amplification circuit amplifies the weak signal from the triaxial accelerometer. The data processing circuit controls each module to ensure the normal operation of the measuring device 4.

[0057] In the above embodiments, the triaxial gravity accelerometer adopts a high-precision anti-vibration quartz accelerometer, with a measurement range covering all tilt angles (-90° to = 90°), a measurement accuracy of ±0.2°, a temperature resistance of 150°, and the use of omnidirectional vibration reduction technology, which greatly improves the shock resistance and vibration resistance, and the vibration resistance reaches 5G / 100Hz (omnidirectional), thus improving the instrument's applicable environment range.

[0058] In the above embodiments, each module can be integrated on the circuit board, and the integration and installation methods are mature existing technologies, which are not the focus of this solution. The circuit board is equipped with an RS232 standard interface to achieve connection with a computer and realize bidirectional communication.

[0059] In the above embodiment, the power module of the measuring device 4 uses a 3V button battery, and a fixed isolation sleeve is used around the battery. The protection circuit itself is fixed and protected with insulating material to ensure that the battery is isolated from the circuit.

[0060] Optionally, in some embodiments, the measuring instrument 4 further includes a clock module, which is electrically connected to the power supply module and the data processing circuit. That is, the clock module controls the start-up time of the measuring instrument 4, i.e., it is in a sleep mode during drilling, and the measuring instrument is woken up by the clock module and then the measurement begins.

[0061] Optionally, in some embodiments, the triaxial accelerometer measurement data is coordinated and matched with the clock module to ensure that each data point corresponds to time, and the depth of the measuring instrument is determined by combining ground timing and downhole timing.

[0062] Optionally, in some embodiments, in order to further save power and improve data storage capacity, a data storage interval can be set, such as recording data once every 10 seconds or every 20 seconds and writing the data into the storage unit.

[0063] A method of use, applied to the above-mentioned oblique coring device;

[0064] Place the measuring device 4 inside the protective shell, then place the protective shell inside the groove 6, and install the cover plate 3 on the groove 6;

[0065] Connect the core sampler 1 to the drill string and insert it into the wellbore to be inspected;

[0066] Tilt angle data is collected using a triaxial accelerometer, and the time of data collection is recorded using a clock module.

[0067] The collected data is stored in the storage unit;

[0068] Remove the core sampler 1 and drill string from the wellbore, remove the measuring instrument 4, and export the data from the storage module.

[0069] In use, first connect the measuring instrument 4 to the computer and set it up. The measurement start time can be estimated according to the well depth. Then, install the instrument into the groove 6, install the cover plate 3, and fix it with bolts. The cover plate 3 is equipped with sealing strips around its perimeter, which can effectively withstand pressure and prevent drilling fluid from entering and damaging the measuring instrument 4. Then, install it into the bottom drill string assembly and between the core bit and the core barrel 1. Then, it is lowered into the well along with the core barrel 1. After drilling to the bottom of the well, start the pump and start core drilling normally. After core drilling is completed, stop the pump and let the drill string stand still for 1 to 3 minutes, and record the time synchronously. Then, pull out the drill string normally. After pulling out to the surface, wipe the centralizer 2 clean with a towel or paper towel, especially the area near the cover plate 3. Then, remove the cover plate 3, take out the measuring instrument 4 and connect it to the computer to read the data. By using the data corresponding to the recorded time, the well bottom inclination data can be detected, thereby realizing the monitoring of the core well trajectory.

[0070] In other words, the key point of this utility model is that the measuring device 4 is installed inside the groove 6 of the stabilizer 2. There are several stabilizers 2, and all of them are installed in the core tube 1 and evenly distributed along the axis of the core tube 1. The stabilizers 2 are used to position and fix the core tube 1, reduce the deviation of the core tube 1, and improve the accuracy of the rock sample. The measuring device 4 installed in the groove 6 of the stabilizer 2 detects the position of the core tube 1. Therefore, the wellbore sampling and inclination measurement can be completed in one go, realizing the measurement of well inclination during the core sampling process, thereby realizing wellbore trajectory monitoring. This avoids the wellbore trajectory deviating too far from the expected or expected distance during the core sampling process, which makes it impossible to monitor. It also reduces the construction steps of separate tripping and inclination measurement, saves drilling time, and reduces construction costs.

[0071] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0072] The foregoing has provided a detailed description of the oblique coring device provided by this utility model. Specific examples have been used to illustrate the principle and implementation of this utility model. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core idea of ​​this utility model. It should be noted that those skilled in the art can make various improvements and modifications to this utility model without departing from its principles, and these improvements and modifications also fall within the protection scope of this utility model.

Claims

1. A device for measuring oblique coring, characterized in that, include: Core tube (1), used to connect with core drill bit and drill string; Several stabilizers (2) are installed on the core tube (1) and evenly distributed along the axis of the core tube (1). At least one stabilizer (2) is provided with a groove (6) and a cover plate (3) for closing the groove (6). The cover plate (3) is detachably installed on the stabilizer (2). Measuring device (4) is placed in the groove (6) and used to collect tilt data of the core tube (1).

2. The oblique coring device according to claim 1, characterized in that, The stabilizer (2) is a strip-shaped structure extending along the axis of the core tube (1), and the stabilizer (2) is detachably installed on the core tube (1).

3. The oblique coring device according to claim 2, characterized in that, The centralizer (2) is provided with guide portions (5) on both sides along the axis of the core tube (1), and the guide portions (5) are used to reduce the resistance when the centralizer (2) moves.

4. The oblique coring device according to claim 3, characterized in that, The centering device (2) has an arc-shaped surface with an opening facing the core tube (1) on the side away from the core tube (1).

5. The oblique coring device according to claim 1, characterized in that, There are several measuring devices (4), and the number is the same as that of the straightener (2). Each of the several measuring devices (4) is installed on the corresponding straightener (2).

6. The oblique coring device according to claim 1, characterized in that, Also includes: A protective shell, the protective shell having a cavity inside, the measuring instrument (4) being placed inside the cavity.

7. The oblique coring device according to claim 6, characterized in that, The measuring device (4) is detachably installed inside the cavity.

8. The oblique coring device according to claim 7, characterized in that, A sealing structure is provided between the cover plate (3) and the straightener (2).

9. The oblique coring device according to any one of claims 1-8, characterized in that, The measuring device (4) includes a storage module, a triaxial accelerometer, a power supply module, a signal amplification circuit, and a data processing circuit. The storage module, the triaxial accelerometer, the signal amplification circuit, and the data processing circuit are all electrically connected to the power supply module.

10. The oblique coring device according to claim 9, characterized in that, The measuring device (4) also includes a clock module, which is electrically connected to the power supply module and the data processing circuit.

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