Testing device for ground simulation borehole wall coring and testing method thereof

Abstract

The invention discloses a testing device for ground simulation borehole wall coring and a testing method of the testing device, and belongs to the technical field of petroleum well logging. The testing device comprises a box body, one side of the box body is connected with a core barrel releaser and a simulation core barrel, and a coring device and a tracking instrument simulation box are installed in the box body. During measurement, the testing device is connected with a cable and a logging program, the cable is pulled up, a high value is recorded when the cable reaches a first stratum near-end line, a low value is recorded when the cable reaches a first stratum far-end line, all stratums are tested, and a stratum curve is obtained; transferring the stratum curve into a coring tracking reference curve making program to form a tracking reference curve; the testing device is pulled back to the original starting point, the cable is pulled up, a real-time logging curve of the stratum is recorded, the depth of the real-time logging curve is made to be the same as the horizon depth of the tracking reference curve, and the simulation core barrel is released; whether coring is correct or not is judged according to the falling position of the simulated core barrel, and the testing device continues to run and judge until simulated coring of all stratums is completed.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil well logging, and particularly relates to a test device for ground-simulated sidewall coring and a test method thereof. Background Art

[0002] Sidewall coring plays an important role in oilfield exploration and development. It can obtain formation physical and chemical parameters by directly detecting real cores, understand the lithology and oil-bearing properties of the formation, and has the advantages of being fast, intuitive, and accurate. Therefore, sidewall coring technology has become an important means to quickly and accurately judge the lithology and oil-bearing properties of difficult horizons.

[0003] The sidewall coring system includes two parts: hardware and software. The performance of both and the technical ability of the operator will directly affect the core quality. Currently, the inspection of sidewall coring results can only be analyzed through the actual coring effect. For incorrect sidewall coring results obtained, it is impossible to accurately determine which specific link has problems. If the problem occurs during well operations, it can only be judged by analysis, which may not be accurate. And the re-verification is still carried out in the well. If the verification result is incorrect, further analysis is still needed, which is time-consuming and laborious, and increases the safety risk. Therefore, a device that can visually inspect the performance of the sidewall coring system is needed. Summary of the Invention

[0004] In order to overcome the above-mentioned drawbacks of the prior art, the purpose of the present invention is to provide a test device for ground-simulated sidewall coring and a test method thereof, so as to solve the problems of low efficiency, low accuracy, and low safety in the method for inspecting the performance of the sidewall coring system.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] In the first aspect of the present invention, a test device for ground-simulated sidewall coring is disclosed, which includes a box body. A core barrel releaser and a simulated core barrel are installed on the side plate of the box body. A corer and a tracking instrument simulation box are installed inside the box body. One end of the tracking instrument simulation box is connected to the corer, and the other end is connected to a cable.

[0007] Among them, the core barrel releaser is in contact with the simulated core barrel and is used to release the simulated core barrel. The tracking instrument simulation box is used to simulate electrode logging signals and natural gamma logging signals.

[0008] Preferably, the core barrel releaser releases the simulated core barrel by means of electromagnetic attraction or by melting plastic with an electric current passing through a resistance wire.

[0009] Further preferably, the core barrel releaser is composed of a rectifying and filtering circuit, an electromagnet and a bracket, and is fixed on the box body through the bracket. One wire of the rectifying and filtering circuit is connected to the internal contact of the core barrel chamber of the core sampler, and the other wire is connected to the outer shell of the core sampler. The rectifying and filtering circuit drives the electromagnet to act and release the simulated core barrel. The simulated core barrel is composed of a heavy object and an iron hook, and the hook is hung on the armature of the electromagnet of the core barrel releaser. After the armature is energized and attracted, the hook falls off and the simulated core barrel is released.

[0010] Preferably, the core barrel releaser is composed of an energizing circuit, a resistance wire and a bracket, and is fixed on the box body through the bracket. One wire of the energizing circuit is connected to the internal contact of the core barrel chamber of the core sampler, and the other wire is connected to the outer shell of the core sampler. The energizing circuit drives the resistance wire to heat up and melt the plastic rope of the simulated core barrel connected to the core barrel releaser, and releases the simulated core barrel. The simulated core barrel is composed of a heavy object connected to the plastic rope, and the plastic rope is hung on the resistance wire of the core barrel releaser. After being energized, the resistance wire of the core barrel releaser heats up and melts the plastic rope, and the simulated core barrel is released.

[0011] Preferably, the tracking instrument simulation box includes a housing and a high-low value switch. Inside the housing, there is a power transformer and a circuit board. On the circuit board, there are a power supply circuit for generating pulse signals, an oscillator, a monostable, a rate meter circuit, a driving circuit and an electrode resistance network for generating electrode signals. The high-low value switch is connected to the circuit board inside the housing.

[0012] Further preferably, a band switch is provided on the surface of the housing.

[0013] Preferably, the box body is composed of a box main body and a box base, and the box base is made of a wooden base or a slide rail or pulley that can slide on the ground.

[0014] Further preferably, the box main body is obtained by connecting a front box body and a rear box body with a pin. The front box body and the rear box body are parallel, and the width of the front box body is greater than the width of the rear box body.

[0015] Preferably, it further includes a cable fixing device, and the cable fixing device is fixed at the end of the box body and is clamped with the cable torpedo.

[0016] In the second aspect of the present invention, a test method for ground simulation well wall coring is disclosed, and the steps are as follows:

[0017] 1) Design several formations, and the length of the cable extended ≥ the length of several formations; connect the above test device to the cable, connect the logging program and set the well depth;

[0018] 2) Pull up the cable. When the testing device reaches the proximal line of the first formation, record it as a high value. When it reaches the distal line of the first formation, record it as a low value. Until all formations are measured to obtain the formation curve. Then, transfer the formation curve into the core-taking tracking reference curve production program to form the tracking reference curve.

[0019] 3) Pull the testing device back to the original starting point, pull up the cable and record the real-time logging curve of the formation, making the depth of the real-time logging curve the same as the layer depth of the tracking reference curve, and release the simulated core barrel. Judge whether the core-taking is correct according to the falling position of the simulated core barrel, and continue to run the testing device for judgment until the simulation core-taking of all formations is completed.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] A testing device for ground simulation of sidewall core-taking provided by the present invention. The setting of the box body can, on the one hand, fix the core barrel release device and the simulated core barrel, accommodate the core-taking device and the tracking instrument simulation box, and on the other hand, as the carrier of the entire simulation testing device, it can be conveniently moved under the drive of the cable. The core barrel release device can release the simulated core barrel to simulate the process of the core barrel being launched into the formation. The simulated core barrel can indicate the core-taking layer. The tracking instrument simulation box can simulate the electrode logging signal and the natural gamma logging signal and transmit the signals to the surface instrument. In addition, by simultaneously simulating the electrode logging signal and the natural gamma logging signal, it can be connected to tracking instruments with different signals to improve the simulation performance of the testing device. This device can simulate the whole process of sidewall core-taking, fully display the abstract various links of sidewall core-taking carried out underground in the ground test site, intuitively show the process and results of core-taking, check the performance of each link of the sidewall core-taking system, solve the problems in time and verify them in time, without the need to verify underground, so it can improve the efficiency, accuracy and safety in the process of testing the sidewall core-taking system, and can be applied to the whole-process training of sidewall core-taking in the ground site and the process inspection of multiple links in the whole process of sidewall core-taking in the ground site.

[0022] A testing method for ground simulation of sidewall core-taking provided by the present invention. By designing several formations, a core-taking well section fixed on the ground surface is established for simulating measurement and core-taking. By measuring the simulated formation curve of the core-taking well section fixed on the ground surface, it is used to produce the tracking curve. By transferring the formation curve into the core-taking tracking reference curve production program, a tracking reference curve is formed for comparing and tracking with the real-time curve. By repeating the measurement and recording steps, the whole core-taking process is simulated to complete the core-taking operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic structural diagram of the box body of the present invention;

[0024] Figure 2 Schematic structural diagram of the test device for ground simulation wellbore coring of the present invention;

[0025] Figure 3 Schematic diagram of the simulated core barrel of the present invention;

[0026] Figure 4 Principle block diagram of the tracking instrument simulation box of the present invention;

[0027] Figure 5 Schematic diagram of the cable fixing device of the present invention;

[0028] Figure 6 Principle block diagram of the core barrel releaser of the present invention;

[0029] Figure 7 Installation schematic diagram of the test device for ground simulation wellbore coring in Embodiment 1 of the present invention;

[0030] Figure 8 Measurement schematic diagram of the test device for ground simulation wellbore coring in Embodiment 1 of the present invention;

[0031] Figure 9 Tracking reference curve diagram in Embodiment 1 of the present invention;

[0032] Figure 10 Depth comparison diagram of the real-time measurement curve and the tracking reference curve in Embodiment 1 of the present invention.

[0033] Wherein: 1 - box body; 1 - 1 - front box body; 1 - 2 - rear box body; 2 - core barrel releaser; 3 - simulated core barrel; 4 - tracking instrument simulation box; 5 - cable fixing device; 6 - coring tool; 7 - connection line; 8 - cable; 9 - high and low value switch. Detailed implementation manners

[0034] In order to enable those skilled in the art of the present technology to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0035] It should be noted that the terms "first", "second", etc. in the description, claims and above-mentioned drawings of the present invention are used to distinguish similar objects and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0036] The present invention will be further described in detail below with reference to the accompanying drawings:

[0037] A test device for ground simulation wellbore coring provided by the present invention includes a box body 1, and the box body 1 is composed of a box main body and a box base. The manufacturing materials of the box main body include but are not limited to wooden products, plastics, and metal products. Since the box body 1 is relatively long, as Figure 1 shown, the box main body is made by connecting a front box body 1-1 and a rear box body 1-2 with pins. The front box body 1-1 is parallel to the rear box body 1-2, and the width of the front box body 1-1 is greater than the width of the rear box body 1-2. The front box body 1-1 is enclosed by a bottom plate and side plates on three vertical surfaces on the bottom plate, and the rear box body 1-2 is enclosed by a bottom plate and side plates on two opposite vertical surfaces on the bottom plate. The box base is made of a wooden base or has sliding rails or pulleys that can slide on the ground to facilitate the movement of the box body 1.

[0038] As Figure 2 shown, the box body 1 serves as a carrier of the entire simulation test device. A core barrel releaser 2 is fixedly installed on the side plate of the box body 1, and the core barrel releaser 2 is connected to a simulated core barrel 3; a coring device 6, a tracking instrument simulation box 4, and a cable fixing device 5 are installed in the box body 1.

[0039] The core barrel releaser 2 is used to release the simulated core barrel 3. The ways for the core barrel releaser 2 to release the simulated core barrel 3 include but are not limited to the way of using an electromagnet to attract. Any instrument that can release the simulated core barrel 3 is within the protection scope. A number of core barrel releasers 2 are provided, and the installation position of each core barrel releaser 2 should be aligned with the core barrel chamber of the coring device 6.

[0040] The simulated core barrel 3 is used to indicate the coring horizon. The simulated core barrel 3 is provided and used in a matching manner with the core barrel releaser 2, and its movement ways include but are not limited to using a hook way to disengage or not disengage from the core barrel releaser 2. A number of simulated core barrels 3 are provided, as Figure 3As shown, the simulated core barrel 3 consists of a heavy object connected to an annular hook, and is connected to the core barrel release device 2 through the annular hook. The process of falling to the ground (equivalent to being launched into the formation) is simulated by separating from the core barrel release device 2.

[0041] The core sampler 6, which is of an existing structure, is electrically connected to the core barrel release device 2 respectively, and is connected to the tracking instrument simulation box 4 through a banana plug or a flexible wire plug, and is used to indicate the installation positions of the core barrel release device 2 and the simulated core barrel 3, and to supply power to the core barrel release device 2.

[0042] The tracking instrument simulation box 4 is used to simulate the electric logging signal and the natural gamma logging signal. The tracking instrument simulation box 4 is connected to the horsehead (or cable torpedo) through a flexible wire plug and is connected to the core sampler 6 through a banana plug or a flexible wire plug. The instrument signals generated by it include, but are not limited to, two values of high value and low value, and can also be multiple values. The generation method is not limited to manual generation, and can also be automatically generated. For example Figure 4As shown, the tracking instrument simulation box 4 is placed on the bottom plate of the box body 1-2 (it can be not fixed), including a housing and a high-low value switch 9. The housing can be made of materials such as metal or plastic; inside the housing, a power transformer and a circuit board are provided. On the circuit board, there are a power supply circuit for generating pulse signals, an oscillator, a monostable, a rate meter circuit, a driving circuit, and an electrode resistance network for generating electrode signals; on the surface of the housing, there are a band switch, jacks for testing, and 3 groups of connecting wires 7. The band switch is preferably a three-pole two-position band switch, which is used to control the natural gamma signal or the electrode signal generated by the tracking instrument simulation box 4; the high-low value switch 9 is connected to the circuit board through a group of connecting wires 7. The process of generating the natural gamma signal in the tracking instrument simulation box 4 is as follows: The surface instrument provides 180V alternating current through the cable 8 and the submersible cable head, which is transformed into low-voltage alternating current through the power transformer, rectified, filtered, and regulated through the power supply circuit to be converted into low-voltage direct current, and supplied to the oscillator, monostable, rate meter circuit, and driving circuit for use. The oscillation circuit can output oscillation signals of two frequencies, representing high count rate and low count rate signals, and the frequency conversion is controlled by the high-low value switch 9. The signal output by the oscillator is sent to the monostable circuit, and the monostable circuit outputs a pulse signal with a width of about 30us, which is used to simulate the natural gamma pulse signal. This pulse signal is sent to the driving circuit for power amplification and then sent to the surface instrument for acquisition through the cable 8. The other way is sent to the rate meter circuit to convert the natural gamma pulse signal into a direct current signal. The level of the direct current signal is proportional to the number of pulses, and after passing through the driving circuit, it is sent to the surface instrument. The process of generating the electrode signal in the tracking instrument simulation box 4 is as follows: After the square wave power supply sent down by the surface instrument through the cable 8 enters the tracking instrument simulation box 4, it generates an analog measurement signal through voltage division by the analog electrode resistance network. The magnitude of the analog measurement signal is controlled by the high-low value switch 9, simulating two signals of low-resistivity resistivity and high-resistivity resistivity. This analog signal is sent back to the surface instrument for acquisition through the cable 8.

[0043] The cable fixing device 5 is used to clamp the cable 8, the cable torpedo, or the submersible cable head and drag the box body 1 to move. The cable fixing device 5 is made of metal materials or hard plastics and other materials, and its structure is preferably a U-shaped buckle structure. The opening width of the U-shaped buckle is greater than the diameter of the cable 8 and less than the diameter of the cable torpedo. As Figure 5 shown, the cable fixing device 5 is fixed at the end of the rear box body 1-2 and is connected to the cable 8, the cable torpedo, or the submersible cable head. When in use, first fix the bottom of the U-shaped buckle to the bottom plate with screws, then use a cover plate or a pin to block the cable 8 at the upper part of the U-shaped buckle to prevent the cable 8 from jumping out. Finally, use the cable fixing device 5 to clamp the cable 8, the cable torpedo, or the submersible cable head on the bottom plate of the box body 1, which is convenient to fasten the cable 8, the cable torpedo, or the submersible cable head and can also be conveniently opened to take out the torpedo or the submersible cable head.

[0044] Embodiment 1

[0045] A test device for ground simulation of sidewall coring includes a box body 1. The box body 1 is made of wooden material with a thickness of 18 cm and consists of two parts: a box body proper and a box base. The box body proper is formed by connecting a front box body 1-1 and a rear box body 1-2 with pins. The front box body 1-1 is enclosed by a bottom plate and side plates on three vertical sides. The length of the front box body 1-1 is 2.5 m, the width is 0.28 m, and the height is 0.2 m. The front box body 1-1 is parallel to the rear box body 1-2. The rear box body 1-2 is enclosed by a bottom plate and side plates on two opposite vertical sides. The length of the rear box body 1-2 is 1.5 m, the width is 0.24 m, and the height is 0.18 m. The box base is made of wooden squares and steel wire cables to facilitate the movement of the box body 1 on the ground.

[0046] A core barrel releaser 2 and a simulated core barrel 3 are installed on the side plates of the box body 1. The core barrel releaser 2 and the simulated core barrel 3 are connected by an electromagnetic suction method. A coring device 6, a tracking instrument simulation box 4, and a cable fixing device 5 are installed inside the box body 1.

[0047] The core barrel releaser 2 is provided with several pieces and is fixed on the side plates of the box body 1. The installation position is aligned with the core barrel chamber of the coring device 6, and the simulated core barrel 3 is released by an electromagnetic suction method. The core barrel releaser 2 consists of a rectifier filter circuit (i.e., a rectifier circuit and a filter circuit), an electromagnet, and a bracket, and is fixed on the side plate of the front box body 1-1 through the bracket. One wire of the rectifier filter circuit is connected to the internal contact of the core barrel chamber of the coring device 6, and the other wire is connected to the outer shell of the coring device 6; the rectifier filter circuit outputs a DC voltage, and the DC voltage drives the electromagnet to act, releasing the simulated core barrel 3, so that the simulated core barrel 3 falls to the ground. As Figure 6 shown, the working principle of the core barrel releaser 2 is: when there is an AC ignition voltage between the ignition contact of the core barrel chamber of the coring device 6 and the outer shell of the coring device 6, this voltage is converted into a DC voltage through the rectifier filter circuit, and the DC voltage drives the electromagnet armature to suck in, causing the simulated core barrel 3 suspended on the armature to fall to the ground, completing the release action.

[0048] The simulated core barrel 3 is provided with several pieces and is composed of a heavy object connected to an iron ring-shaped hook. The hook is suspended on the armature of the electromagnet of the core barrel releaser 2. After the armature is energized and sucked in, the hook falls off, and the simulated core barrel 3 falls to the ground, completing the indication function of the coring horizon.

[0049] The tracking instrument simulation box 4 is set on the bottom plate of the box body 1-2, and includes a housing and a high-low value switch 9. The housing is made of metal materials. Inside the housing, a power transformer and a circuit board are provided. On the circuit board, there are a power supply circuit for generating pulse signals, an oscillator, a monostable circuit, a rate meter circuit, a driving circuit, and an electrode resistance network for generating electrode signals. On the surface of the housing, there are a three-knife two-position band switch, jacks for testing, and 3 groups of connecting wires 7. The high-low value switch 9 is connected to the simulation box 4 through 1 group of connecting wires 7. The tracking instrument simulation box 4 is connected to the horsehead through a soft wire plug and to the core sampler 6 through a banana plug to complete the simulation function of natural gamma logging signals or electrode logging signals.

[0050] The cable fixing device 5 is made of metal materials and is of a U-shaped buckle structure. The opening width of the U-shaped buckle is greater than the diameter of the cable 8 and less than the diameter of the cable torpedo. During use, first fix the bottom of the U-shaped buckle to the bottom plate with screws, then use a cover plate or a pin to block the cable torpedo at the upper part of the U-shaped buckle to prevent the cable 8 from jumping out. Finally, use the cable fixing device 5 to clamp the cable torpedo on the bottom plate at the end of the rear box body 1-2, which is convenient for buckling the cable torpedo and can also be easily opened to take out the cable torpedo and the horsehead.

[0051] A test method for ground simulation of sidewall coring is used to illustrate the process of simulating coring in a ground site by the above test device. The whole process is divided into four stages, namely, designing the formation, measuring the formation curve, making the tracking reference curve, and simulating coring. The specific steps are as follows:

[0052] (1) Design the formation and install the test device

[0053] Find a test site about 100 meters long to install the test device. As Figure 7 shown, first connect the front box body 1-1 and the rear box body 1-2 at one end of the test site through pins. According to the use requirements, install several core barrel release devices 2 on the side plate of the front box body 1-1, and hang the corresponding number of simulated core barrels 3 on the armatures of the core barrel release devices 2. Place the core sampler 6 on the bottom plate of the front box body 1-1. Connect one wire of the rectifier filter circuit of the core barrel release device 2 to the internal contact of the core barrel chamber of the core sampler 6, and the other wire to the shell of the core sampler 6. Install the tracking instrument simulation box 4 and the cable fixing device 5 in the rear box body 1-2. Then connect the upper joint of the core sampler 6 to the lower joint of the tracking instrument simulation box 4, and finally connect the upper joint of the tracking instrument simulation box 4 to the lower joint of the horsehead. Connect the upper joint of the horsehead to the cable torpedo (the cable torpedo is the connection end of the cable 8 and has been riveted to the cable 8 as a whole), and use the cable fixing device 5 to fix the cable 8.

[0054] Place the instrument vehicle at the other end of the test site with the rear of the vehicle facing the direction of the test device. Draw 8 to 9 boxes representing the strata along the straight-line distance between the test device and the instrument vehicle. The width of the box represents the thickness of the strata, and thicknesses such as 0.3 m, 0.5 m, 1 m, 2 m, etc. can be selected. The initial position of the test device can be assumed to be a well depth of 1000 m (arbitrarily set).

[0055] (2) Measure the formation curve

[0056] The surface instrument enters the logging program, sets the well depth to 1000 m, and selects to use either the resistivity curve measurement or the natural gamma curve measurement. Start the winch, pull up the cable 8, and drag the test device to run at a constant speed while recording the logging curve. At this time, a low-value curve is recorded. When the front edge of the box 1 is parallel to the near-end line of the box on the ground, press the high-low value switch 9. At this time, the recorded curve value becomes high. When the front edge of the box 1 approaches the far-end line of the box, release the high-low value switch 9. At this time, the measured value changes back to low. In this way, one formation is measured. The test device continues to run and the same operation is performed when it reaches the second box until all formations (boxes) are measured, as Figure 8 shown.

[0057] (3) Make the tracking reference curve

[0058] Transfer the formation curve obtained in process (2) into the program for making the coring tracking reference curve, as Figure 9 shown. According to the requirements of the coring horizon position, mark points at the high-value positions of the curve. For example, now it is necessary to mark points at the center position of the horizon to form the tracking reference curve.

[0059] (4) Simulate coring

[0060] Lower the cable 8 of the winch to pull the test device back to the original starting point. The surface instrument enters the coring program, sets the well depth to 1000 m, selects to use the resistivity curve tracking, transfer the coring tracking reference curve obtained in process (3), place it on the left side of the screen, and place the real-time measurement curve on the right side of the screen. Start the winch, pull up the cable 8, and drag the test device to run at a constant speed while recording the logging curve. At this time, a low-value curve is recorded. When the front edge of the box 1 is parallel to the near-end line of the box on the ground, press the high-low value switch 9. At this time, the recorded curve value becomes high. When the front edge of the box 1 approaches the far-end line of the box, release the high-low value switch 9. At this time, the measured value changes back to low. In this way, one formation is measured. As Figure 10 shown, the newly measured real-time measurement curve is compared with the reference curve in depth, and the depth of the real-time measurement curve is moved to make it the same as the horizon depth of the tracking reference curve.

[0061] When the real-time depth is the same as the depth of the marker point, the core barrel release 2 enters the countdown preparation, and the test device continues to run. When the countdown length (automatically calculated by the program) is 0 m, the armature of the core barrel release 2 is attracted, simulating the dropping of the core barrel 3, completing the simulation action of coring in the wellbore wall. By checking the position where the simulated core barrel 3 drops, it can be determined whether the coring is correct.

[0062] The box body 1 continues to run and operates in the same way when it reaches the second box until the simulation coring of all strata (boxes) is completed, and the overall effect is checked.

[0063] Embodiment 2

[0064] The difference from Embodiment 1 is that the materials used and the release methods of the core barrel release 2 and the simulated core barrel 3 are different.

[0065] A number of core barrel releases 2 are provided and are all fixed on the side plates of the box body 1. The installation positions are aligned with the core barrel chambers of the core sampler 6, and the simulated core barrel 3 is released by the way of melting plastic through the energization of the resistance wire. The core barrel release 2 is composed of an energized circuit, a resistance wire and a bracket, and is fixed on the side plate of the front box body 1-1 through the bracket. One wire of the energized circuit is connected to the internal contact of the core barrel chamber of the core sampler 6, and the other wire is connected to the outer shell of the core sampler 6; the energized circuit drives the resistance wire to heat up, melting the plastic rope of the simulated core barrel 3 connected to the core barrel release 2, so that the simulated core barrel 3 drops to the ground, completing the release action.

[0066] A number of simulated core barrels 3 are provided, each consisting of a heavy object connected to a plastic rope. The plastic rope is suspended on the resistance wire of the core barrel release 2. After being energized, the resistance wire of the core barrel release 2 heats up and melts the plastic rope, and the simulated core barrel 3 drops to the ground, completing the indication function of the coring horizon.

[0067] The above content is only to illustrate the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any modification made on the basis of the technical solution according to the technical idea proposed by the present invention falls within the protection scope of the claims of the present invention.

Claims

1. A test device for ground simulation of sidewall coring, characterized in that It includes a box body (1), a core barrel releaser (2) and a simulated core barrel (3) are installed on the side plate of the box body (1), a core sampler (6) and a tracking instrument simulation box (4) are installed inside the box body (1), one end of the tracking instrument simulation box (4) is connected to the core sampler (6), and the other end is connected to a cable (8); Among them, the core barrel releaser (2) is in contact with the simulated core barrel (3) and is used to release the simulated core barrel (3), and the tracking instrument simulation box (4) is used to simulate the electrode logging signal and the natural gamma logging signal.

2. The test device for ground simulation of sidewall coring according to claim 1, characterized in that, The core barrel releaser (2) releases the simulated core barrel (3) by means of electromagnetic suction or by melting plastic with an energized resistance wire.

3. The testing device for ground simulated sidewall coring according to claim 2, wherein The core barrel releaser (2) consists of a rectifying and filtering circuit, an electromagnet and a bracket, and is fixed to the box body (1) through the bracket. One wire of the rectifying and filtering circuit is connected to the internal contact of the core barrel chamber of the core sampler (6), and the other wire is connected to the outer shell of the core sampler (6). The rectifying and filtering circuit drives the electromagnet to act and release the simulated core barrel (3); the simulated core barrel (3) consists of a heavy object and an iron hook, and the hook is suspended on the armature of the electromagnet of the core barrel releaser (2). After the armature is energized and attracted, the hook falls off and the simulated core barrel (3) is released.

4. The test device for ground simulated sidewall coring according to claim 2, characterized in that, The core barrel releaser (2) consists of an energizing circuit, a resistance wire and a bracket, and is fixed to the box body (1) through the bracket. One wire of the energizing circuit is connected to the internal contact of the core barrel chamber of the core sampler (6), and the other wire is connected to the outer shell of the core sampler (6). The energizing circuit drives the resistance wire to heat up and melts the plastic rope of the simulated core barrel (3) connected to the core barrel releaser (2) to release the simulated core barrel (3); the simulated core barrel (3) consists of a heavy object connected to a plastic rope, and the plastic rope is suspended on the resistance wire of the core barrel releaser (2). After being energized, the resistance wire of the core barrel releaser (2) heats up and melts the plastic rope, and the simulated core barrel (3) is released.

5. A test device for ground simulation of sidewall coring, according to any one of claims 1 to 4, characterized in that, The tracking instrument simulation box (4) includes a housing and a high-low value switch (9). Inside the housing, there is a power transformer and a circuit board. On the circuit board, there are a power supply circuit for generating pulse signals, an oscillator, a monostable, a ratemeter circuit, a driving circuit and an electrode resistance network for generating electrode signals; the high-low value switch (9) is connected to the circuit board inside the housing.

6. The test device for ground simulation of sidewall coring according to claim 5, characterized in that, A band switch is provided on the surface of the housing.

7. A test device for ground simulation of sidewall coring according to any one of claims 1 to 4, characterized in that, The box body (1) consists of a box body proper and a box base, and the box base is made of a wooden base or a slide rail or pulley that can slide on the ground.

8. A test device for ground simulation of sidewall coring, according to claim 7, characterized in that, The box body proper is obtained by connecting a front box body (1-1) and a rear box body (1-2) with a pin. The front box body (1-1) is parallel to the rear box body (1-2), and the width of the front box body (1-1) is greater than the width of the rear box body (1-2).

9. A test device for ground simulation of sidewall coring, according to any one of claims 1 to 4, characterized in that It also includes a cable fixing device (5), and the cable fixing device (5) is fixed at the end of the box body (1) and is clamped with a cable torpedo.

10. A test method for ground simulation of sidewall coring, characterized in that, The steps are as follows: 1) Design several formations, and the length of the cable (8) extending out ≥ the length of several formations; Connect the test device described in any one of claims 1 to 9 to the cable (8), connect the logging program and set the well depth; 2) The pull-up cable (8). When the testing device reaches the proximal line of the first formation, it is recorded as a high value, and when it reaches the distal line of the first formation, it is recorded as a low value. This process continues until all formations are measured to obtain the formation curve. Then, the formation curve is imported into the core-taking tracking reference curve production program to form the tracking reference curve. 3) Pull the testing device back to the original starting point, pull up the cable (8) and record the real-time logging curve of the formation, making the depth of the real-time logging curve the same as the layer depth of the tracking reference curve, and release the simulated core barrel (3). Determine whether the core-taking is correct based on the falling position of the simulated core barrel (3), and continue to run the testing device for judgment until the simulation core-taking of all formations is completed.

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