CN111577268A - Method for judging rock lithology by using drilling tool vibration parameters - Google Patents
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Abstract
The invention discloses a method for judging rock lithology by using drilling tool vibration parameters, which comprises the following steps: extracting vibration data of the drilling tool; analyzing rock lithology according to the acceleration root mean square, the stress-strain relation and the mechanical specific energy by using the vibration data; wherein the mechanical specific energy is the minimum energy required to remove a unit volume of rock. The method adopted by the invention has simpler operation steps and is easy to use. The method for analyzing the lithology of the rock mass by using the vibration data is an innovative method. The method has good operability and economic value in well logging, not only saves complex and tedious operation processes in well logging, but also greatly saves the construction period, and has great benefit for accelerating the progress of engineering construction.
Description
Technical Field
The invention relates to the technical field of rock mass measurement, in particular to a method for judging rock lithology by using vibration parameters of a drilling tool.
Background
Well-logging technology has become an essential part of the well-drilling operation today. The well logging technology is an engineering technical measure for testing a reservoir by applying a geophysical method. Through the application of various sound, light, electricity, magnetism, radioactivity and the like, the physical parameters of the stratum are reflected, various logging information is obtained, and the information is further explained and analyzed, so that the method is applied to drilling engineering.
In the drilling engineering, the measurement of the lithology of the drilling surrounding rock has important significance. The lithology of rock has direct correlation to the progress speed of drilling engineering. After the lithology of the drilling surrounding rock is successfully measured, the technical personnel can clearly analyze the overall lithology distribution condition of the drilling surrounding rock and the change condition of the lithology along with the drilling depth. Due to the continuity of the stratum, when the lithology of a certain drilling surrounding rock is clear, a technician can design an implementation scheme of drilling according to the change rule of the lithology of the stratum. The types of rocks change along with the increasing drilling depth of the drilling tool in the drilling process. Because of the different strength of different rock masses, the drill bit used for drilling needs to be continuously adjusted in order to meet the drilling requirements. Therefore, the types of the drill bits required in the drilling process can be reasonably designed and adjusted according to the lithological condition of the stratum, so that the drilling efficiency is improved, and the occurrence of drilling faults is reduced. Meanwhile, in petroleum drilling, after workers correctly master the lithology distribution condition of the stratum, the hydraulic fracturing area can be effectively designed to provide the yield of oil and gas. Because the choice of hydraulic fracturing zone is extremely important, brittle rock mass is more easily fractured than plastic rock mass and can produce larger fractures.
The existing well logging technology can measure rock lithology and mainly comprises acoustic wave well logging technology, imaging well logging technology, resistivity well logging technology and radioactive well logging technology. The acoustic logging mainly applies the characteristics of drilling and then carries out acoustic emission, which is a common method in the drilling logging, and the acoustic properties of the stratum surrounding the borehole are judged according to the method, so that the characteristics of the stratum and the soil course condition of the borehole are analyzed; imaging logging is a highly comprehensive technique that can be applied to a large number of electronic devices, and also to a computer that is equipped to analyze data based on a data analyzer. The imaging technology can be used for obtaining a high-quality map, and the contained information content is complete; the working principle of the resistivity logging technology is mainly that a logging instrument is used for transmitting current into a stratum, and then the resistivity generated by the current in the stratum is calculated, so that geological data of the bottom layer is obtained; the radioactive logging technology is used for researching and analyzing the properties of nuclear substances in interstitial fluid between formation rocks.
However, these techniques are based on indirect information for lithology determination and do not involve the interaction of the drill bit with the formation. Meanwhile, the methods have complicated operation steps and more limiting factors, and need specialized instruments for matching use, so the use price is high. The method analyzes the lithology of the rock according to the vibration data measured by the near-bit, fully utilizes the data generated by measurement while drilling, and fills the gap that the lithology of the rock cannot be measured by the measurement while drilling. The method for measuring the lithology of the rock has the advantages of more accurate measuring result, simpler operation and capability of saving more time and economic cost, thereby improving the engineering efficiency.
Therefore, the invention is especially provided.
Disclosure of Invention
The invention aims to provide a method for judging rock lithology by using vibration parameters of a drilling tool, which is simple to operate and easy to use.
In order to solve the above problems, an embodiment of the present invention provides a method for determining rock lithology by using drill tool vibration parameters, including the following steps:
extracting vibration data of the drilling tool;
analyzing rock lithology according to the acceleration root mean square, the stress-strain relation and the mechanical specific energy by using the vibration data; wherein the mechanical specific energy is the minimum energy required to remove a unit volume of rock.
Further, analyzing the rock lithology according to the root mean square of the acceleration comprises: and calculating the root mean square of the acceleration of the drilling tool by using the axial acceleration of the drilling tool, and analyzing the lithology according to the root mean square of the acceleration.
Further, the calculating the root mean square of the acceleration of the drilling tool by using the axial acceleration of the drilling tool, and the analyzing the lithology according to the root mean square of the acceleration comprises:
(1) acquiring triaxial accelerometer data Ax, Ay and Az stored in a measuring short section;
(2) carrying out filtering processing on the triaxial acceleration data;
(3) calculating the root mean square value RMS of the axial acceleration Az in unit time;
(4) judging the change of rock lithology in the drilling process according to the RMS numerical value change condition; when the RMS value is increased, the strength of the rock body drilled by the drilling tool is reduced; when the RMS value decreases, it indicates that the strength of the rock mass drilled by the drill tool increases.
Further, analyzing rock lithology according to the stress-strain relationship includes:
(1) extracting data in a near-drilling recorder, completing data conversion, and performing filtering treatment to remove clutter to obtain data of axial acceleration and axial angular velocity;
(2) when the drilling tool drills in a vertical rock stratum, the maximum main stress borne by the drilling tool is torsion1The minimum principal stress being the axial stress3(ii) a In unit time T, the drilling displacement of the drilling tool is3(ii) a At this time, the root mean square value of the angular acceleration is regarded as the torque force1(ii) a The root mean square value of the axial acceleration is taken as the axial stress3(ii) a Axial displacement per unit time of3A zero frequency value equivalent to the axial displacement spectrum;
(3) when the drilling direction of the drilling tool is parallel to the rock stratum, the maximum main stress borne by the drilling tool is axial stress1The minimum principal stress being the torsion3(ii) a In unit time T, the drilling displacement of the drilling tool is3(ii) a The root mean square value of the axial acceleration is regarded as the axial stress1(ii) a The root mean square value of the angular acceleration is taken as the torque force3(ii) a Axial displacement per unit time of3A zero frequency value equivalent to the disclination spectrum;
and obtaining the stress-strain relation according to the data.
Further, the mechanical specific energy comprises two parts, one part is the energy E in the axial direction of the drill bit1The other part is the torsional energy E perpendicular to the axial direction of the drill bit2。
Further, the energy E in the axial direction of the drill bit1The axial force of the drill bit is multiplied by the axial displacement of the drill bit to obtain the axial force; torsional energy E2Calculated from the torsional displacement multiplied by the torque force.
Further, analyzing rock lithology based on mechanical specific energy includes:
(1) selecting axial acceleration from the data which is subjected to the modulation filtering, and then calculating the root mean square value of the axial acceleration by using the axial acceleration;
(2) at the moment, the axial displacement in unit time is equal to the zero frequency value of the axial displacement spectrum;
(3) calculating the energy E axially acting on the rock mass in unit time according to the steps (1) and (2)1。
(4) Calculating angular acceleration according to data recorded by a gyroscope, and calculating the rotary displacement of the drilling tool in unit time by using the angular acceleration;
(5) and calculating the root mean square value of the angular acceleration according to the calculated angular acceleration.
(6) Calculating the rotation energy E consumed by the drilling tool according to the steps (4) and (5)2。
(7) Calculating the consumed specific energy according to the calculation results of the steps (3) and (6), and judging the lithology strength according to the required specific energy of different rock masses; when the specific energy is larger along with the continuous drilling of the drill bit, the rock strength is increased.
Furthermore, results calculated by three analysis methods of the acceleration root mean square, the stress-strain relation and the mechanical specific energy are compared, and the mutual dependence relation of the results of the three analysis methods is judged by using correlation analysis.
Compared with the prior art, the invention has the following beneficial effects: the method adopted by the invention has simpler operation steps and is easy to use. The method for analyzing the lithology of the rock mass by using the vibration data is an innovative method. The method has good operability and economic value in well logging. Not only saves the complex and fussy operation process in logging, but also greatly saves the construction period, and has great benefit for accelerating the progress of engineering construction.
In modern engineering drilling, vibration measurement is widely used to analyze the vibration condition and the posture of the drilling tool. The data utilized by the method is generally consistent with the types of data for judging the vibration condition of the drilling tool and the posture of the drilling tool. Therefore, the lithology of the rock mass drilled by the drilling tool is analyzed and judged by using the vibration data of the drilling tool, but the vibration data is fully utilized, the related operations in the logging work are reduced, and a large amount of time and economic cost are saved.
Drawings
FIG. 1 is a general flow chart of a method for determining rock lithology using vibration parameters of a drilling tool according to an embodiment of the present invention;
FIG. 2 is a flowchart illustrating a method for determining lithology of rock using vibration parameters of a drilling tool according to an embodiment of the present invention;
FIG. 3 is a flow chart of data processing for stress-strain relationships;
FIG. 4 is a diagram illustrating a stress state when the symmetry axis of the rock formation is parallel to the borehole;
FIG. 5 is a diagram illustrating the stress state when the symmetry axis of the rock formation is perpendicular to the borehole.
Detailed Description
The principles and spirit of the present invention will be described with reference to a number of exemplary embodiments shown in the drawings. It should be understood that these embodiments are described only to enable those skilled in the art to better understand and to implement the present invention, and are not intended to limit the scope of the present invention in any way.
Abbreviations and Key term definitions
Short section: fitting commonly used in industrial pipeline
Sealing the cabin: cabin isolated from the outside environment and capable of containing a certain volume of equipment
Cover plate: a lid, cover or top for closing or covering a cross-section of a container or structure.
The embodiment of the invention provides a method for judging basic lithology and lithology change of a drilling tool drilling rock mass based on near-bit vibration data measured by an accelerometer and a gyroscope and analyzing data recorded by a recorder by utilizing a stress-strain relation and a specific energy method.
In order to invent a set of such methods, the inventor pays a great deal of creative work in researching technical principles, and the research process of the principles is not equal to the technical scheme of the embodiment of the invention, but is an important part for embodying the inventive concept of the invention.
The drilling process of the drilling tool is the process of breaking rock mass by the drill bit, and the vibration of the drilling tool is the result of the interaction between the drill bit and the rock mass. When the drill bit interacts with the rock mass, the drill bit applies an acting force to the rock mass, the rock mass deforms under the action of the force, and the rock mass fractures when the force exceeds the strength limit of the rock mass. When the drill bit is drilled into rock bodies of different types, the lithology of the rock can be changed along with the change of the rock, and the vibration condition generated by the drilling tool can be changed during crushing due to the different lithology of the rock. The drill bit interacts with the rock mass in the drilling process of the drilling tool, and the lithology of the rock mass changes along with the drilling depth of the drill bit, so that the drilling state of the drilling tool is different in the drilling process, and vibration data generated near the drill bit are different. The vibration data generated by the interaction of the drill bit and the rock mass can relatively directly reflect the drilling condition of the drilling tool. Therefore, the method utilizes the vibration data of the drilling tool recorded by the recorder under different drilling conditions to analyze the lithology of the rock body drilled by the drill bit and the lithology change trend of the rock body. The operation steps are shown in the flow chart 1.
The method utilizes data which are recorded by a recorder and related to the vibration of the drilling tool to complete the analysis of the lithology and the lithology change of the rock body. The analysis of rock lithology is completed by processing and analyzing data from three aspects, namely (1) the rock lithology change is judged by using the root mean square of acceleration. (2) Judging lithology and change trend thereof according to the stress-strain relation; (3) judging the change condition of lithology according to a mechanical specific energy method;
(1) and judging the rock lithology change by using the root mean square of the acceleration. When the drilling tool drills normally, if the lithology of the rock drilling body is single and other conditions are kept unchanged, the drilling speed of the drill bit is kept stable. At the moment, the drilling speed fluctuation is small, namely the root mean square change value of the axial acceleration in unit time is small. When the drill bit drills to a rock layer boundary, the lithology of the rock body can be changed, and the rock body strength of two sides of the boundary is different. When the lithology of the rock mass changes, the vibration of the drill bit caused by the interaction between the rock mass and the drill bit changes after the drill bit applies stress to the rock mass. Meanwhile, when a rock fracture is encountered in the drilling process, the root mean square value of the drilling acceleration is changed, but the change time is short and the original stable state can be recovered, so that the rock fracture can be identified by the method.
(2) And judging the lithology and the change trend thereof according to the stress-strain relation. The drill bit rock body can be regarded as a transversely isotropic medium (TI), and the drill vibration is a result of the interaction of the drill bit with the rock mass. When the drill bit applies acting force to the rock mass, the rock mass is deformed under the action of the force, and when the force exceeds the strength limit of the rock mass, the rock mass is fractured, and the drill bit can drill along with the fracture. According to the principle, the elastic modulus E and the Poisson ratio Pr of the rock mass can be calculated by utilizing the stress-strain relation.
(3) And judging the change condition of the lithology according to the specific energy method. Specific energy refers to the minimum energy required to remove a unit volume of rock mass during drilling. The drilling speed and the cutting depth of the drill bit can be effectively known through the mechanical specific energy, so that the change trend of the rock mass strength can be known through the change situation of the numerical values. The method provides a means of measuring the strength of a rock mass, i.e. the minimum energy required to remove the rock mass. Because the strength of different rock masses is different, the energy required to remove the same amount of rock mass is different. When the energy required to remove the same volume of rock mass changes, it is an indication that the lithology of the rock has changed. It is therefore feasible to use the amount of energy required by the rock drilling rig to determine the strength of the rock mass.
Thus, the method may analyze lithology according to the following steps, as shown in flow chart 2. Firstly, extracting vibration data from a related recorder, and performing primary processing-data conversion by adopting self-service programming software; after the data is processed by the edited software, the data is subjected to high-frequency filtering processing, so that the basic processing of the data is completed. And then analyzing the lithology of the rock by using different data according to the three methods, analyzing and comparing according to the analysis results of the three methods, and finally obtaining a final result.
The following describes a method for determining rock lithology by using drill tool vibration parameters according to an embodiment of the present invention, including the following steps:
extracting vibration data of the drilling tool;
analyzing rock lithology according to the acceleration root mean square, the stress-strain relation and the mechanical specific energy by using the vibration data; wherein the mechanical specific energy is the minimum energy required to remove a unit volume of rock. The detailed steps of the above three methods are described below.
1. Analysis of lithology using root mean square acceleration
(1) And acquiring data Ax, Ay and Az of the three-axis accelerometer stored in the measuring short section.
(2) And basic filtering processing is carried out on the triaxial acceleration data, so that the measurement error is reduced.
(3) And calculating the root mean square value of the axial acceleration Az in unit time, firstly squaring the acceleration, then taking the mean value (time is T, sampling number is N) after squaring, and finally squaring the calculation result to obtain the root mean square RMS of the acceleration.
(4) And judging the change of the rock lithology in the drilling process according to the RMS numerical value change condition. When the RMS value is increased, the strength of the rock body drilled by the drilling tool is reduced, and the drilling tool drills into the region with lower rock body strength from the region with higher rock body strength; when the RMS value decreases, indicating that the strength of the rock mass drilled by the drilling tool increases, the drilling tool drills from a region of lower rock mass strength to a region of higher rock mass strength.
Root mean square value RMS calculation formula:
axial acceleration is axial acceleration.
According to the method, the variation condition of the root mean square value of the acceleration can be judged, so that the vibration condition of the drilling tool in the drilling process can be deduced. When the RMS changes, it indicates that the drill bit is in the process of drilling, and a crack or lithologic boundary is met.
2. Lithology analysis according to stress-strain relationship
The drilling process is the process of rock mass destruction, and the drilling tool is drilled after the rock mass is destroyed by stress. Under normal working conditions of the drilling tool, the vibration of the drilling tool is mainly the result of the interaction between the rock mass and the drilling tool. The method considers the rock mass to be a transverse uniform medium (TI), and under the condition, the rock mass lithology is analyzed by applying a stress-strain relation. The specific steps are shown in a flow chart 3;
(1) data installed in a near-drilling recorder is extracted, relevant software is used for completing data conversion work and filtering processing is carried out to remove clutter, so that the interference of the clutter is reduced, and the precision of an analysis result is improved. Axial acceleration A after modulation filteringZAxial angular velocity data ω.
(2) And the stress conditions of the drilling tool are different under different drilling conditions according to the analysis. When the drilling direction of the drilling tool is vertical to the rock stratum, the drill bit (rock body) is mainly subjected to torsion1Axial force3Acting; when the drilling direction of the drilling tool is parallel to the rock stratum, the drill bit (rock body) is mainly subjected to axial force1Torsion force3Acting; as shown in fig. 4 and 5.
Stress-strain calculation formula:
(3) when the drilling tool drills vertically to the rock stratum, the largest main stress borne by the drilling tool (rock mass) is torsion1The minimum principal stress being the axial force3. In unit time T, the drilling displacement of the drilling tool is3。
(4) Maximum principalStress being torsional1First, angular acceleration α is calculated using angular velocity data ω, and then RMS is calculated using a root mean square RMS calculation formulaAngular acceleration. (this torsional force)1Can be measured by a torque sensor
(5) The minimum principal stress being axial stress3The axial acceleration RMS value can then be considered as axial stress.
(6) Axial displacement per unit time of3At this point the axial displacement is equivalent to ZFL (zero frequency value) of the axial displacement spectrum. The method comprises the steps of firstly carrying out fast Fourier transform on axial acceleration by utilizing processed axial acceleration, then carrying out twice integration on a transformed result, and obtaining a result after carrying out double integration, namely ZFL (zero frequency value) of an axial displacement spectrum.
(7) When the drilling direction of the drilling tool is parallel to the rock stratum, the maximum main stress borne by the drill bit (rock mass) is axial force1The minimum principal stress being the torsion3. In unit time T, the drilling displacement of the drilling tool is3。
(8) The maximum principal stress being the axial force1At this time, the root mean square value of the acceleration may be regarded as the axial force. RMS calculation using root mean square RMS calculation formulaAxial acceleration。
(9) The minimum principal stress being a torsion3First, angular acceleration α is calculated using angular velocity data ω, and then RMS is calculated using a root mean square RMS calculation formulaAngular acceleration. (this torsional force)1Can be measured by a torque sensor
(10) Rotational displacement per unit time of3At this time, the disclination is equivalent to ZFL (zero frequency value) of the disclination spectrum. The method uses the processed angular velocity, firstly carries out fast Fourier transform on the rotational angular velocity, then integrates the transformed result, and the result obtained after the integration is the ZFL (zero frequency value) of the rotational displacement spectrum.
3. Analysis of lithology according to mechanical specific energy method
Specific energy refers to the minimum amount of work required to remove a unit volume of rock while drilling. The drilling speed and the cutting depth of the drill bit can be effectively known through a specific energy method, so that the change trend of the rock mass strength can be known through the change situation of the numerical values. When the energy required by the rock mass per unit volume is larger, the rock mass is harder. The invention thus provides, in accordance with this principle, a method of measuring rock mass strength: rock lithology is judged from measuring the minimum energy required to remove the rock mass.
From the mechanics principle, the energy required to remove a unit volume of rock can be multiplied by the force on the drill bit by the drill bit displacement. Specific energy can be divided into two parts: a part of the energy E in the axial direction of the drill bit1The other part is perpendicular to the axial direction (torsional energy) E of the drill bit2。
The specific energy calculation formula is as follows:
MSE＝E1+E2
E1＝RMSaxial acceleration·ZELAxial displacement；
Where ω is the axial angular velocity and f is the rotational frequency. Axial section E1The axial force of the drill bit can be multiplied by the axial displacement of the drill bit to calculate; torsional energy E2Can be obtained from the torsional displacement multiplied by the torque force. The specific operation steps are as follows:
(1) selecting axial acceleration A from data which has finished modulation filteringShaftAnd then calculating the root mean square value of the axial acceleration by using the axial acceleration.
(2) The axial displacement in unit time is then equivalent to ZFL (zero frequency value) of the axial displacement spectrum. The method comprises the steps of firstly carrying out fast Fourier transform on axial acceleration by utilizing processed axial acceleration, then carrying out twice integration on a transformed result, and obtaining a result after carrying out double integration, namely ZFL (zero frequency value) of an axial displacement spectrum.
(3) From steps 1 and 2 units can be calculatedEnergy E acting axially on rock mass in time1。
(4) And according to the data recorded by the gyroscope, calculating the angular velocity change-angular acceleration alpha of adjacent time periods, and calculating the rotary displacement of the drilling tool in unit time by using the angular acceleration.
(5) The root mean square value RMS of the angular acceleration is calculated from the angular acceleration that has been calculated.
(6) According to the steps 4 and 5, the rotation energy E consumed by the drilling tool can be calculated2。
(7) And (4) calculating the consumed specific energy according to the calculation results of the steps 3 and 6, and judging the lithology strength according to the required specific energy of different rock masses. When the specific energy is larger along with the continuous drilling of the drill bit, the rock strength is increased.
4. Comprehensive analysis of rock lithology
The three methods can complete the analysis of the lithology of the rock, and the three methods are integrated to increase the analysis precision in consideration of the existence of noise interference and calculation errors. The method compares the results calculated by the three analysis methods, and judges the mutual dependence relationship of the results of the three analysis methods by using correlation analysis. As the three methods are all used for directly analyzing the lithology of the rock, the results of the three methods have better similarity.
The invention provides a technical scheme for analyzing lithology. The scheme adopts an innovative measurement method, vibration data and lithology analysis are effectively combined, and the lithology is analyzed and judged by using methods such as stress-strain relation, mechanical specific energy and the like. The aim of judging the lithology of the rock mass by using the vibration data can be achieved only by the scheme. Other technical solutions that do not have a significant innovation point different from the present solution on the basis of the present solution can be considered to be within the scope of the present solution.
The inventive concept is explained in detail herein using specific examples, which are given only to aid in understanding the core concepts of the invention. It should be understood that any obvious modifications, equivalents and other improvements made by those skilled in the art without departing from the spirit of the present invention are included in the scope of the present invention.
Claims (8)
1. A method for judging rock lithology by using drilling tool vibration parameters is characterized by comprising the following steps:
extracting vibration data of the drilling tool;
analyzing rock lithology according to the acceleration root mean square, the stress-strain relation and the mechanical specific energy by using the vibration data; wherein the mechanical specific energy is the minimum energy required to remove a unit volume of rock.
2. The method of claim 1, wherein analyzing rock lithology from root mean square acceleration comprises: and calculating the root mean square of the acceleration of the drilling tool by using the axial acceleration of the drilling tool, and analyzing the lithology according to the root mean square of the acceleration.
3. The method of claim 2, wherein the calculating a root mean square of the acceleration of the drilling tool using the axial acceleration of the drilling tool, and the analyzing the lithology from the root mean square of the acceleration comprises:
(1) acquiring triaxial accelerometer data Ax, Ay and Az stored in a measuring short section;
(2) carrying out filtering processing on the triaxial acceleration data;
(3) calculating the root mean square value RMS of the axial acceleration Az in unit time;
(4) judging the change of rock lithology in the drilling process according to the RMS numerical value change condition; when the RMS value is increased, the strength of the rock body drilled by the drilling tool is reduced; when the RMS value decreases, it indicates that the strength of the rock mass drilled by the drill tool increases.
4. The method of claim 1, wherein analyzing rock lithology according to a stress-strain relationship comprises:
(1) extracting data in a near-drilling recorder, completing data conversion, and performing filtering treatment to remove clutter to obtain data of axial acceleration and axial angular velocity;
(2) when the drilling tool drills in a vertical rock stratum, the maximum main stress borne by the drilling tool is torsion1The minimum principal stress being the axial stress3(ii) a In unit time T, the drilling displacement of the drilling tool is3(ii) a At this time, the root mean square value of the angular acceleration is regarded as the torque force1(ii) a The root mean square value of the axial acceleration is taken as the axial stress3(ii) a Axial displacement per unit time of3A zero frequency value equivalent to the axial displacement spectrum;
(3) when the drilling direction of the drilling tool is parallel to the rock stratum, the maximum main stress borne by the drilling tool is axial stress1The minimum principal stress being the torsion3(ii) a In unit time T, the drilling displacement of the drilling tool is3(ii) a The root mean square value of the axial acceleration is regarded as the axial stress1(ii) a The root mean square value of the angular acceleration is taken as the torque force3(ii) a Axial displacement per unit time of3A zero frequency value equivalent to the disclination spectrum;
and obtaining the stress-strain relation according to the data.
5. The method of claim 1, wherein the mechanical specific energy comprises two components, one component being the energy E in the axial direction of the drill bit1The other part is the torsional energy E perpendicular to the axial direction of the drill bit2。
6. The method of claim 5, wherein the energy E in the axial direction of the drill bit1The axial force of the drill bit is multiplied by the axial displacement of the drill bit to obtain the axial force; torsional energy E2Calculated from the torsional displacement multiplied by the torque force.
7. The method of claim 6, wherein analyzing the rock lithology based on the mechanical specific energy comprises:
(1) selecting axial acceleration from the data which is subjected to the modulation filtering, and then calculating the root mean square value of the axial acceleration by using the axial acceleration;
(2) at the moment, the axial displacement in unit time is equal to the zero frequency value of the axial displacement spectrum;
(3) calculating the energy E axially acting on the rock mass in unit time according to the steps (1) and (2)1。
(4) Calculating angular acceleration according to data recorded by a gyroscope, and calculating the rotary displacement of the drilling tool in unit time by using the angular acceleration;
(5) and calculating the root mean square value of the angular acceleration according to the calculated angular acceleration.
(6) Calculating the rotation energy E consumed by the drilling tool according to the steps (4) and (5)2。
(7) Calculating the consumed specific energy according to the calculation results of the steps (3) and (6), and judging the lithology strength according to the required specific energy of different rock masses; when the specific energy is larger along with the continuous drilling of the drill bit, the rock strength is increased.
8. The method according to claim 1, wherein the results of the three analysis methods of root mean square acceleration, stress-strain relationship and mechanical specific energy are compared, and correlation analysis is used to determine the interdependence of the results of the three analysis methods.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104977234A (en) * | 2015-06-23 | 2015-10-14 | 安徽理工大学 | Pressure rock failure and instability process and dynamic permeability test apparatus and method thereof |
| CN106640035A (en) * | 2016-12-19 | 2017-05-10 | 四川宏华电气有限责任公司 | VFD control system and method for automatic optimization of drilling parameters |
| CN107842390A (en) * | 2016-09-21 | 2018-03-27 | 河南理工大学 | A kind of method based on drilling rod vibration characteristics identification butt entry roof lithology |
| US20190153859A1 (en) * | 2014-09-10 | 2019-05-23 | Fracture ID, Inc. | Apparatus and method using measurements taken while drilling to map mechanical boundaries and mechanical rock properties along a borehole |
| CN109798100A (en) * | 2018-12-25 | 2019-05-24 | 中国石油集团长城钻探工程有限公司 | Stratum based on nearly drill bit engineering parameter measurement-while-drilling judges recognition methods |
-
2020
- 2020-05-25 CN CN202010448832.5A patent/CN111577268B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20190153859A1 (en) * | 2014-09-10 | 2019-05-23 | Fracture ID, Inc. | Apparatus and method using measurements taken while drilling to map mechanical boundaries and mechanical rock properties along a borehole |
| CN104977234A (en) * | 2015-06-23 | 2015-10-14 | 安徽理工大学 | Pressure rock failure and instability process and dynamic permeability test apparatus and method thereof |
| CN107842390A (en) * | 2016-09-21 | 2018-03-27 | 河南理工大学 | A kind of method based on drilling rod vibration characteristics identification butt entry roof lithology |
| CN106640035A (en) * | 2016-12-19 | 2017-05-10 | 四川宏华电气有限责任公司 | VFD control system and method for automatic optimization of drilling parameters |
| CN109798100A (en) * | 2018-12-25 | 2019-05-24 | 中国石油集团长城钻探工程有限公司 | Stratum based on nearly drill bit engineering parameter measurement-while-drilling judges recognition methods |
Non-Patent Citations (1)
| Title |
|---|
| 吴蔚娓等: "存储式井下振动测量仪的应用研究", 《石化技术》 * |
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