CN111796003A - Core resistivity measuring device and measuring method thereof - Google Patents
Core resistivity measuring device and measuring method thereof Download PDFInfo
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- CN111796003A CN111796003A CN202010847707.1A CN202010847707A CN111796003A CN 111796003 A CN111796003 A CN 111796003A CN 202010847707 A CN202010847707 A CN 202010847707A CN 111796003 A CN111796003 A CN 111796003A
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- core
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
- G01N27/041—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
Abstract
The invention discloses a core resistivity measuring device and a measuring method thereof, and relates to the technical field of core resistivity measurement, wherein the core resistivity measuring device comprises a measuring instrument, a fixed frame, a pressure loading device fixed on the fixed frame, an upper base and a lower base for clamping a core, grooves for fixing the end part of the core are arranged on the upper base and the lower base, a pressure sensor, an electrode plate and a sponge gasket soaked by electrolyte solution are sequentially stacked between the end part of the core and the bottom surface of the groove, the sponge gasket is contacted with the end part of the core, and the pressure sensor and the electrode plate are electrically connected with the measuring instrument; according to the invention, the sponge gasket soaked by the electrolyte solution can ensure good contact between the electrode plate and the rock core, and prevent the larger contact resistance between the electrode plate and the rock core from influencing the experimental result; and through setting up the sponge gasket, when the installation, the sponge gasket can play the effect of buffering, and the impact when preventing the installation destroys pressure sensor.
Description
Technical Field
The invention relates to the technical field of core resistivity measurement, in particular to a core resistivity measurement device and a core resistivity measurement method.
Background
With the continuous consumption of mineral resources, shallow resources are basically explored and developed, and the exploration and development of mineral resources are carried out towards deep parts at present. The electromagnetic exploration technology is an important technical means for deep mineral resource exploration. The technical premise of electromagnetic exploration is to fully master the resistivity distribution characteristics of deep rocks. The core is taken out by drilling and resistivity parameter measurement is the main method for knowing the deep rock resistance distribution at present. At present, the main measurement method of the resistivity of the rock core is based on a symmetric quadrupole method, the resistivity of the rock core is measured under normal pressure, but after the rock core is taken out from the underground deep part, the pressure environment is changed, and the measured resistivity value is difficult to represent the real resistivity of the underground deep part rock.
Therefore, the invention provides the rock core resistivity tester capable of loading pressure in real time, and the aim of measuring the real resistance of the deep rock core is achieved by changing the pressure during measurement.
Disclosure of Invention
The invention aims to provide a core resistivity measuring device and a core resistivity measuring method, which are used for solving the problems in the prior art, can accurately measure the resistivity of a core under different axial pressures, and are simpler in structure and more convenient to operate.
In order to achieve the purpose, the invention provides the following scheme: the invention provides a rock core resistivity measuring device which comprises a measuring instrument, a fixed frame, a pressure loading device fixed on the fixed frame, an upper base and a lower base, wherein the upper base and the lower base are used for clamping a rock core; grooves for fixing the end parts of the rock cores are formed in the upper base and the lower base, and the two grooves are coaxially arranged;
the measuring instrument is characterized in that a pressure sensor, an electrode plate and a sponge gasket soaked by electrolyte solution are sequentially stacked between the end part of the core and the bottom surface of the groove, the sponge gasket is in contact with the end part of the core, and the pressure sensor and the electrode plate are electrically connected with the measuring instrument.
Preferably, the upper base is connected with the movable end of the pressure loading device by a connecting bolt, and the upper base is coaxially arranged with the movable end of the pressure loading device.
Preferably, the adjustable movable part is a screwing bolt which is fixed on the fixed frame in a threaded connection mode.
Preferably, the pressure loading device is a telescopic oil cylinder.
Preferably, the electrode plate is made of copper.
The invention also provides a core resistivity measuring method implemented by applying the core resistivity measuring device, which is characterized by comprising the following steps of:
step one, sampling for standby: selecting a cylindrical core, polishing, soaking the core in an electrolyte solution after polishing, and measuring the length and the diameter of the core after soaking;
step two, mounting a test piece: firstly, connecting the electrode plate with a measuring instrument; then soaking two sponge gaskets in an electrolyte solution, respectively arranging the two sponge gaskets on the two electrode sheets, placing the rock core in a groove of the lower base, and adjusting a screwing bolt to enable the top end of the rock core to be tightly pressed by the upper base;
loading axial pressure and starting measurement: changing the pressure applied to the rock core by the pressure loading device, reading the current value flowing through the rock core and the potential difference between the two electrode plates displayed on the measuring instrument, and calculating the formula according to the resistivity
Obtaining the resistivity values of the rock cores under different axial pressure conditions; wherein L is the core length, r is the core radius, I is the current value flowing through the core, and Delta U is the potential difference between the two electrode plates.
Preferably, the soaking time of the core in the electrolyte solution is at least 48 hours.
Preferably, the length L of the core is not more than 300mm, and the radius r is not more than 50 mm.
Preferably, the electrolyte solution is a saturated copper sulfate solution.
Compared with the prior art, the invention has the following technical effects:
1. according to the invention, the sponge gasket soaked by the electrolyte solution can ensure good contact between the electrode plate and the rock core, and prevent the larger contact resistance between the electrode plate and the rock core from influencing the experimental result; the sponge gasket is arranged, so that the sponge gasket can play a role in buffering when being installed, and the pressure sensor is prevented from being damaged by impact during installation;
2. according to the invention, the pressure sensor, the electrode plate and the sponge gasket are stacked, so that the occupied volume is smaller, the structure is more compact, and the force can be directly transmitted to the rock core, so that the measurement is more accurate; the core is fixed by arranging the grooves on the upper base and the lower base, so that the fixing structure is simpler, and the installation process is more convenient;
3. according to the invention, the upper base is connected with the movable end of the pressure loading device by the connecting bolt, so that the upper bases with different groove sizes can be replaced more conveniently, and the resistivity of cores with more sizes can be measured.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.
FIG. 1 is a schematic view of the overall structure of the present invention;
FIG. 2 is an enlarged view of a portion of FIG. 1;
wherein, 1, fixing the frame; 2. a pressure loading device; 3. a core; 4. an upper base; 5. a lower base; 6. an adjustable movable portion; 7. a groove; 8. a pressure sensor; 9. an electrode sheet; 10. a sponge pad; 11. an oil inlet hole; 12. a piston.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention aims to provide a core resistivity measuring device and a core resistivity measuring method, which are used for solving the problems in the prior art, can accurately measure the resistivity of a core under different axial pressures, and are simpler in structure and more convenient to operate.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
Example 1:
as shown in fig. 1 to 2, the present embodiment provides a core 3 resistivity measuring device, which includes a measuring instrument, a fixed frame 1, a pressure loading device 2 fixed on the fixed frame 1, an upper base 4 and a lower base 5 for clamping a core 3, wherein the upper base 4 is fixed at a movable end of the pressure loading device 2, the lower base 5 is fixed at an end of an adjustable movable portion 6, both the upper base 4 and the lower base 5 are provided with grooves 7 for fixing the end of the core 3, and the two grooves 7 are coaxially arranged;
a pressure sensor 8, an electrode plate 9 and a sponge gasket 10 soaked by electrolyte solution are sequentially stacked between the end part of the core 3 and the bottom surface of the groove 7, the sponge gasket 10 is in contact with the end part of the core 3, and the pressure sensor 8 and the electrode plate 9 are both electrically connected with a measuring instrument; the specific positions and electrical connection methods of the wire holes are well known to those skilled in the art, and therefore, are not described in detail in this embodiment.
In the testing process, the core 3 is clamped between the upper base 4 and the lower base 5, the loading pressure of the pressure loading device 2 is changed, the measuring instrument can measure the potential difference between the two electrode plates 9 under different axial pressures and the current value flowing through the core 3, and the conductivity of the core 3 under different axial pressures can be measured according to a formula.
In this embodiment, the pressure sensor 8 and the electrode plate 9 are used for transmitting measured pressure data and current potential data to the measuring instrument, and the sponge pad 10 soaked by the electrolyte solution has strong conductivity, so that good contact between the electrode plate 9 and the rock core 3 can be ensured, and the experimental result is prevented from being influenced by large contact resistance between the electrode plate 9 and the rock core 3.
In the embodiment, the sponge gasket 10 is arranged, so that when the pressure sensor is installed, the sponge gasket 10 can play a role in buffering due to high elastic deformation capacity, and the pressure sensor 8 is prevented from being damaged by impact during installation; and pressure sensor 8, electrode piece 9, sponge gasket 10 three range upon range of, and it is littleer to occupy the volume on the one hand for the structure is compacter, and on the other hand can directly transmit power to rock core 3, measures more accurately.
This embodiment realizes fixing rock core 3 through set up recess 7 on last base 4 and lower base 5, and fixed knot constructs simplyr, and the installation is also more convenient.
Furthermore, the upper base 4 is connected with the movable end of the pressure loading device 2 by adopting a connecting bolt, so that the upper base 4 with different groove 7 sizes can be replaced more conveniently, and the resistivity of the rock core 3 with more sizes can be measured; and the upper base 4 and the movable end of the pressure loading device 2 are coaxially arranged, so that force is uniformly and axially applied to the upper base 4, and the accuracy of measurement is ensured.
In this embodiment, the adjustable movable portion 6 is a tightening bolt.
In this embodiment, the pressure loading device 2 is a telescopic cylinder, the telescopic cylinder has an oil inlet 11, and the piston 12 is connected to the upper base 4 through a connecting bolt. The telescopic oil cylinder is flexible and smooth, and can realize accurate control on pressure.
In this embodiment, the electrode plate 9 is made of copper and has a thickness of 3mm to 5 mm; of course, other electrode sheets 9 having excellent conductivity may be used.
Example 2:
the embodiment provides a core resistivity measurement method implemented by applying the core resistivity measurement device, which is characterized by comprising the following steps of:
step one, sampling for standby: selecting a cylindrical rock core 3, polishing, soaking the rock core 3 in an electrolyte solution after polishing is finished, and measuring the length and the diameter of the rock core 3 after soaking;
step two, mounting a test piece: firstly, connecting the electrode plate 9 with a measuring instrument; then soaking two sponge gaskets 10 in an electrolyte solution, respectively installing the two sponge gaskets on two electrode plates 9, placing the core 3 in the groove 7 of the lower base 5, and adjusting a screwing bolt to enable the top end of the core 3 to be tightly pressed by the upper base 4;
loading axial pressure and starting measurement: changing the pressure applied to the rock core 3 by the pressure loading device 2, reading the current value flowing through the rock core 3 and the potential difference between the two electrode plates 9 displayed on the measuring instrument, and calculating the formula according to the resistivity
Obtaining the resistivity values of the rock core 3 under different axial pressure conditions; wherein, L is the length of the core 3, r is the radius of the core 3, I is the current value flowing through the core 3, and Δ U is the potential difference between the two electrode sheets 9.
Since most of the rock in the crust is in groundwater environment, the core needs to be soaked in water sufficiently before measurement, so as to simulate the actual water-containing condition, and in order to ensure sufficient soaking, the soaking time of the core 3 in the electrolyte solution is at least 48h in the embodiment.
Further, in order to ensure that the core 3 can completely permeate within a specified time and ensure the accuracy and convenience of measurement, the length L of the core 3 is not greater than 300mm and the radius r is not greater than 50mm in the embodiment.
Further, the electrolyte solution is a saturated copper sulfate solution, but other saturated electrolyte solutions may be used.
The adaptation according to the actual needs is within the scope of the invention.
The principle and the implementation mode of the invention are explained by applying a specific example, and the description of the embodiment is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.
Claims (9)
1. A rock core resistivity measuring device is characterized by comprising a measuring instrument, a fixed frame, a pressure loading device fixed on the fixed frame, an upper base and a lower base, wherein the upper base is used for clamping a rock core; grooves for fixing the end parts of the rock cores are formed in the upper base and the lower base, and the two grooves are coaxially arranged;
the measuring instrument is characterized in that a pressure sensor, an electrode plate and a sponge gasket soaked by electrolyte solution are sequentially stacked between the end part of the core and the bottom surface of the groove, the sponge gasket is in contact with the end part of the core, and the pressure sensor and the electrode plate are electrically connected with the measuring instrument.
2. The core resistivity measuring device as claimed in claim 1, wherein the upper base is connected with the movable end of the pressure loading device by a connecting bolt, and the upper base is coaxially arranged with the movable end of the pressure loading device.
3. The core resistivity measuring device as claimed in claim 1, wherein the adjustable movable portion is a tightening bolt which is fixed on the fixed frame in a threaded manner.
4. The core resistivity measurement device according to claim 1, wherein the pressure loading device is a telescopic cylinder.
5. The core resistivity measuring device as claimed in claim 1, wherein the electrode sheet is made of copper.
6. A core resistivity measurement method implemented by using the core resistivity measurement device according to any one of claims 1 to 5, is characterized by comprising the following steps:
step one, sampling for standby: selecting a cylindrical core, polishing, soaking the core in an electrolyte solution after polishing, and measuring the length and the diameter of the core after soaking;
step two, mounting a test piece: firstly, connecting the electrode plate with a measuring instrument; then soaking two sponge gaskets in an electrolyte solution, respectively arranging the two sponge gaskets on the two electrode sheets, placing the rock core in a groove of the lower base, and adjusting a screwing bolt to enable the top end of the rock core to be tightly pressed by the upper base;
loading axial pressure and starting measurement: changing the pressure applied to the rock core by the pressure loading device, reading the current value flowing through the rock core and the potential difference between the two electrode plates displayed on the measuring instrument, and calculating the formula according to the resistivity
Obtaining the resistivity values of the rock cores under different axial pressure conditions; wherein L is the core length, r is the core radius, I is the current value flowing through the core, and Delta U is the potential difference between the two electrode plates.
7. The method for measuring core resistivity as claimed in claim 6, wherein the core is soaked in the electrolyte solution for at least 48 hours.
8. The method as recited in claim 6, wherein the core has a length L of no greater than 300mm and a radius r of no greater than 50 mm.
9. The method as recited in claim 6, wherein the electrolyte solution is a saturated copper sulfate solution.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202010847707.1A CN111796003A (en) | 2020-08-21 | 2020-08-21 | Core resistivity measuring device and measuring method thereof |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010847707.1A CN111796003A (en) | 2020-08-21 | 2020-08-21 | Core resistivity measuring device and measuring method thereof |
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| CN111796003A true CN111796003A (en) | 2020-10-20 |
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| CN202010847707.1A Pending CN111796003A (en) | 2020-08-21 | 2020-08-21 | Core resistivity measuring device and measuring method thereof |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115342947A (en) * | 2022-10-18 | 2022-11-15 | 四川大学 | Electrochemical pressure sensor based on metal corrosion effect |
| CN115877044A (en) * | 2022-11-30 | 2023-03-31 | 南通市飞宇石油科技开发有限公司 | Resistivity rock core holder |
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