RU2539089C1 - Method and system of automated determination and recording of hardness of mine rock of working face during well drilling - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: method involves action on a mine rock and its destruction with a rotating indenter under load, determination of hardness parameters using the value of applied load and area of contact surface of the indenter. Measurements are made immediately during drilling in a differential form: mechanical drilling speed or time of duration of a certain depth interval, a value of speeds or time is adjusted by variation of load on a bit; the bit load value is measured at moment of equality of speeds or times and hardness of mine rock is determined as per an algorithm.

EFFECT: optimisation of a well drilling process.

4 cl, 1 dwg

Description

The invention relates to methods for determining the strength and hardness of rocks by applying mechanical forces to them and can be used in mining, drilling.

A known method of determining the elastic characteristics of the rock according to measurements in the well (US Pat. RF No. 2449122, IPC E21B 49/00, op. 27.04.2012. Bull. No. 12), the technical result of which is to determine the elastic characteristics of the rock according to the measurement in a well of radial displacement of the walls of an inclined or horizontal well after opening a given interval of a formation by a well. In a given interval, the radial displacements of the lateral and upper walls of the deviated well are determined by measuring the radii in two mutually perpendicular directions. Next, the mean square deviation and confidence intervals for the displacement of the walls of the well are calculated from the measurement results. Then, two systems of equations for the side and upper walls are compiled, the wells connecting the corresponding displacements of the walls of the well with the elastic characteristics of the rock, with the geostatic pressure and with the hydrostatic pressure of the drilling fluid and the angle of curvature of the well. The systems are solved by the method of successive approximation with respect to the deformation modulus and the actual coefficient of lateral thrust of rocks.

The disadvantage of this method is the inability to determine the hardness of the rock directly during the drilling process, since drilling and measurements, based on which the elastic properties of the rock in the prototype are determined, are spaced in time.

A known method for determining the strength of rocks and a device for its implementation (US Pat. RF No. 2204121, IPC G01N 3/40, op. December 27, 2001), including the impact on the rock and its destruction by the indenter rotating under load, in the process of destruction simultaneously measure the power of acoustic vibrations in the bottom-hole zone and the speed of the relative movement of the indenter and the rock and determine the strength of the rock. The disadvantage of both the method and the device implementing it is that they relate to laboratory facilities and it is impossible to use them in the drilling process. In addition, the disadvantage of the method and device should be attributed to the fact that with their help is determined only an indicator of strength, and not its value.

The closest method is to determine the strength of the rock, including various types of mechanical impact on the rock, the destruction of the rock, the determination of strength using the value of the applied load, the area of the contact surface of the indenter or the area of the hole of destruction in the rock (Lyubimov N.I., Nosenko L.I. Handbook of physicomechanical parameters of rocks in ore regions (Moscow: Nedra, 1978).

A disadvantage of the known method for determining rock strength is the difference in the shape of the indenters used and the rate of application of the load on the rock from the shape of the rock cutting tool and the rate of application of force when the tool is exposed to the rock. This leads to a sharp difference between the mechanism of destruction of rocks during testing from that implemented in production conditions. As a result, the strength of the rock, determined by these methods, does not reflect the real strength of the rock.

The well-known system: drilling - a set of sensors (primary measuring transducers (PIP) of technological parameters of drilling - a station for geological and technological research (GTI), collecting, processing, recording and storing information. At the same time, the GTI station includes the issuance of recommendations for improving the drilling process based on the data obtained (EE Lukyanov. Geological, technological and geophysical research in the process of drilling. - Novosibirsk: Publishing House House “Historical Heritage of Siberia”, 2009, 752 from.).

The disadvantage of the system is that it does not have a module (unit) with which it is possible to carry out measurements in a differential form: the load on the bit G, the mechanical drilling speed or the duration of drilling for a certain depth interval T.

The objective of the invention is the determination and registration of the hardness of the rock bottom and based on the obtained geological information to optimize the further process of drilling the well.

This object is achieved by the fact that in the method for determining the hardness of the rock bottom while drilling, including the impact on the rock and its destruction by the rotating and under load indenter, the determination of hardness using the value of the applied load and the contact surface area of the indenter, according to the invention measurements are carried out directly in the process of drilling in differential form: mechanical drilling speed ϑ or time continuously drilling a certain interval of depth T, by changing the load on the bit, equalize the values of speeds or times, measure the value of the load on the bit at the moment of equal speeds or times and determine the hardness of the rock face using the algorithm

,

,

- твердость горной породы неизвестная (определяемая), соответствующая последующей точке измерения по глубине скважины или времени;Where

- rock hardness unknown (determined), corresponding to the subsequent measurement point by the depth of the well or time;

- твердость горной породы известная (уставка), соответствующая предыдущей точке измерения по глубине скважины или времени или выбранная, например, по результатам эксперимента;

- known rock hardness (set point), corresponding to the previous measurement point by the depth of the well or time, or selected, for example, according to the results of the experiment;

G _i - the load on the bit corresponding to the hardness of the rock and measured at the next measurement point;

G _i-1 - the load on the bit corresponding to the hardness of the rock measured at the previous measurement point, i.e. appropriate setting.

или

а сам алгоритм примет видIn addition, to control the hardness of the rock, violated due to changing downhole conditions, the equality of the algorithm, an indicator term is introduced into it

or

and the algorithm itself will take the form

или

or

where ϑ _i is the mechanical drilling speed at the subsequent measurement point in depth;

ϑ _i-1 - mechanical drilling speed at the previous measurement point in depth;

T _i is the duration of the subsequent drilling interval;

T _i-1 - the duration of the previous drilling interval.

In addition, the restoration of violated equality of the algorithm is carried out by changing the load on the bit - numerator of the algorithm until the ratio of speeds or times is equal to unity, i.e. indicator member of the algorithm, moreover, at the moment of equal relations to one, the value of the load on the bit - the numerator of the algorithm is measured.

The system for the automated determination and registration of hardness of bottom rock during well drilling, including the load sensors for the bit, the movement of the tackle block, the winch and the GTI station with software that collects, processes and records information, differs in that a dispatch module is introduced into the system performing consolidation at measurement points through a step of sampling in depth or time of the indicated devices to solve the problem of determining and recording the hardness of a face rock, when it during the rest of the devices are operating normally.

Algorithm for the relationship of the flow rate of the washing fluid Q, the hardness of the rock bottom P _n , technological parameters that destroy this rock, - the load on the bit G and the number of revolutions n, has the form

;Where

;

V _Iz - the volume of the destroyed rock for a single act of interaction of the tooth of the bit with the rock of the face;

Sk ₀ - surface area of the tooth of the bit in contact with the rock bottom;

γ _p - specific gravity of the rock being destroyed;

γ _s.p. - the specific gravity of the flushing fluid in the annulus;

γ _W - the specific gravity of the flushing fluid pumped into the well.

We assume that A, G, n are constant for at least one trip. Then (1) can be written for neighboring measurement points:

We take the ratio of formulas (2a) and (2b) and get

- твердость горной породы на глубине H_i, т.е. на последующей точке измерения;Where

- rock hardness at a depth of H _i , i.e. at the next measuring point;

- твердость горной породы на глубине H_i-1, т.е на предыдущей точке измерения.

- rock hardness at a depth of H _i-1 , i.e. at the previous measurement point.

Moreover, ΔH = H _i -H _i-1 is the sampling step in depth, varying from 0.1 to 1 m and which is set, for example, programmatically depending on the well conditions.

From (3) we have

The obtained expressions (3), (4) only confirm the conclusion that the load on the bit depends only on the hardness of the rock being destroyed by the face (A.A. Pogarsky. Automation of the deep hole drilling process. - M :. Nedra, 1972, 216 pp.) . Since the hardness of the rock is constantly changing as the face deepens, expression (4) is better represented as inequality, i.e.

The resulting expression (5) is convenient for use in laboratory conditions. Its use in the drilling process, when the changing but hard to determine hardness of the face rock is at a great distance from the mouth (the place of determination and registration), is almost impossible, because in the inequality there is no member of the moment-fixing equality of the left and right sides of formula (5).

или

получимThe mechanical drilling speed ϑ or the duration of the drilling of a certain interval of depth T is very sensitive to changes in the conditions at the bottom, especially to changes in the hardness of the rock, and their reaction is almost instantaneous. Therefore, we introduce the equality indicator in formula (5) in the form of a ratio of speeds (time) (a relation is nothing more than differential with respect to unity), i.e.

or

we get

,

,

where ϑ _i and ϑ _i-1 - respectively, the mechanical drilling speed at a depth of H _i and H _i-1 ;

T _i and T _i-1 - respectively, the drilling time of the drilling intervals at a depth of H _i and H _i-1 .

,

. Это равенство скоростей есть момент превращения неравенств (6а и 6б) в равенства, т.е. когда создается условие вычисления неизвестной величины твердости горной породы

по выражениям (4) или (6а) и (6б), преобразуемым в равенства. Последовательность процедур по определению твердости горной породы по полученным алгоритмам (6а) и (6б) подобна взвешиванию некоего продукта на стрелочных весах. В нашем случае роль стрелки играет отношение

или

, колеблющееся относительно единицы. Неизвестная и подлежащая определению твердость горной породы

находится на одной условной чаше весов (забой), на другой условной чаше (устье) находится известная величина твердости (мера или уставка)

и соответствующее ей известное усилие G_i-1 (знаменатель выражений), а также измеряемая величина разновесного усилия G_i (числитель). Изменением разновесного усилия G_i добиваемся равенства ϑ_i=ϑ_i-1 или T_i=T_i-1, т.е. когда

,

. Момент равенства этих отношений единице соответствует превращению неравенств (6а) или (6б) в равенства, по которым теперь можно вычислять неизвестную твердость горной породы забоя. На этом процесс взвешивания заканчивается. Значение меры (уставка)

и соответствующее этой мере значение усилия G_i-1 выбирается из различных соображений. Во-первых, величину меры и соответствующее усилие можно получить экспериментально по методу Шрейнера и использовать ее для определения твердости породы забоя и непрерывной регистрации на всем протяжении как по глубине скважины, так и по времени, т.е. в виде градиентной кривой. Во-вторых, в качестве меры может использоваться каждое последующее определенное значение твердости породы и соответствующее ей усилие. Тогда каждое последующее вычисленное значение твердости породы и измеренное усилие (нагрузка на долото) становится предыдущей мерой (уставкой) для очередного процесса измерения и вычисления. Такая последовательность обновления меры (уставки) эквивалентна дифференциальному методу измерений. В этом случае должны четко выделяться границы раздела между слоями пород с незначительным отличием твердостей, а также реагировать на приближающуюся зону АВПД. Таким образом, регистрацию твердости горной породы можно осуществлять в двух форматах:Indeed, with an increase (decrease) in rock hardness, ceteris paribus, the penetration rate ϑ _i (numerator) will decrease (increase) relative to a fixed (previous) speed in the denominator ϑ _i-1 (increase (decrease) time T _i relative to T _i-1 ). By changing the load on the bit G _i in the numerator in the direction of increasing (decreasing) the speed ϑ _i and decreasing (increasing) the time T _{i, we} obtain the condition ϑ _i = ϑ _i-1 , T _i = T _i-1 or

,

. This equality of speeds is the moment of transformation of inequalities (6a and 6b) into equalities, i.e. when a condition is created for calculating an unknown rock hardness value

by expressions (4) or (6a) and (6b), which are transformed into equalities. The sequence of procedures for determining rock hardness according to the obtained algorithms (6a) and (6b) is similar to weighing a certain product on an arrow scale. In our case, the role of the arrow is played by the relation

or

fluctuating relative to unity. Unknown and to be determined rock hardness

located on one conventional bowl (bottom), on another conventional bowl (mouth) is a known value of hardness (measure or setting)

and the corresponding known force G _i-1 (denominator of expressions), as well as the measured value of the equilibrium stress G _i (numerator). By changing the equilibrium force G _{i, we} obtain the equality ϑ _i = ϑ _i-1 or T _i = T _i-1 , i.e. when

,

. The moment of equality of these relations to unity corresponds to the transformation of inequalities (6a) or (6b) into equalities, from which it is now possible to calculate the unknown hardness of the face rock. This completes the weighing process. Measure value (set point)

and the corresponding value of the force G _i-1 is selected from various considerations. Firstly, the size of the measure and the corresponding effort can be obtained experimentally by the Schreiner method and used to determine the hardness of the face rock and to continuously record all along both the depth of the well and time, i.e. in the form of a gradient curve. Secondly, each subsequent determined value of the hardness of the rock and the corresponding force can be used as a measure. Then each subsequent calculated value of the hardness of the rock and the measured force (load on the bit) becomes the previous measure (setting) for the next process of measurement and calculation. Such a sequence of updating the measure (setting) is equivalent to the differential measurement method. In this case, the interface between the rock layers with a slight difference in hardness should be clearly distinguished, and also respond to the approaching zone of the airspace pressure drop. Thus, rock hardness can be recorded in two formats:

- continuous - relative to the selected (predetermined) measure;

- differential, when each subsequent calculated hardness value becomes the previous measure for the next measurement and calculation process.

The above described essentially discloses the sequence of procedures and the necessary means to implement these procedures in determining the hardness of the rock face. Figure 1 shows a system for calculating and recording the hardness of a rock, on which:

1 - bit load sensor;

2 - displacement sensor of the traveling block, which allows to determine the current depth of the well, instantaneous speed and mechanical speed for the sampling step in depth;

3 - winch;

4 - dispatcher module;

5 - information collection software;

6 - manual input of information;

7 - information processing software;

8 - program for visualization and registration of information;

9 - a chronometer that measures calendar time and discretizes information by time, and the sampling steps in depth and time must be synchronized;

10 - registrar (printer);

11 - station for geological and technological research (GTI).

и соответствующая ей величина нагрузки на долото G_i-1, а также с датчика 2 значение текущей механической скорости ϑ_i-1 или время T_i-1 с хронометра 9. При этом процесс бурения осуществляется в штатном режиме. При приближении к точке измерения, определяемой шагом дискретизации по глубине или времени, задаваемым программой 5, эта же программа в этот момент фиксирует значения нагрузки G_i с датчика 1, механической скорости ϑ_i с датчика 2 или время T_i с хронометра 9. Полученные данные программа 5 передает в модуль 4, где определяется отношение

или

. Если эти отношения не равны единице, то модуль 4 вырабатывает сигнал на запуск в работу лебедки 3, которая начнет работать в сторону выравнивания скоростей или времени, устремляя отношения к единице. Как только это отношение будет равно единице, модуль 4 снимет сигнал, заставляющий работать лебедку. Одновременно сигнал поступит с модуля 4 в программу 5, по которому она примет значения нагрузки G_i с датчика. Теперь все необходимые данные для вычисления твердости горной породы, т.е.

, G_i, G_i-1, поступят с программы 5 в программу 7, которая вычислит значение твердости по алгоритмуThe newly introduced module 4 essentially performs dispatching functions to consolidate devices and means at the necessary time for the implementation of the proposed algorithm for determining and recording the hardness of the rock face and existing in modern systems for monitoring and control of drilling processes (E.E. Lukyanov. Geological, technological and geophysical research in the process of drilling. - Novosibirsk: Publishing House "Historical Heritage of Siberia", 2009, 752 pp.). Shown in figure 1, the system operates as follows. By manually entering information 6 at the required depth or at the right time, the hardness of the rock, for example, determined previously, i.e. measure (setting)

and the corresponding value of the load on the bit G _i-1 , as well as from sensor 2, the value of the current mechanical speed ϑ _i-1 or time T _i-1 from the chronometer 9. In this case, the drilling process is carried out in normal mode. When approaching the measurement point, determined by the sampling step in depth or time specified by program 5, the same program at this moment fixes the load values G _i from sensor 1, mechanical speed ϑ _i from sensor 2 or time T _i from chronometer 9. Received data program 5 transfers to module 4, where the relation is determined

or

. If these relations are not equal to unity, then module 4 generates a signal to start the winch 3, which will begin to work in the direction of equalizing speeds or time, directing the relationship to unity. As soon as this ratio is equal to unity, module 4 will remove the signal that makes the winch work. At the same time, the signal will come from module 4 to program 5, according to which it will receive the load values G _i from the sensor. Now all the necessary data for calculating the hardness of the rock, i.e.

, G _i , G _i-1 , will come from program 5 to program 7, which will calculate the hardness value according to the algorithm

.

.

Next, the obtained hardness value from program 7 enters program 8, under the control of which the printer 10 registers the result.

The subsequent steps of measurement, calculation and registration will be repeated throughout the required depth of the well or the necessary time.

It should be noted that the hardness values of the bottom rock obtained at the first step of sampling in depth or time and the corresponding load on the bit must be used as a measure (setting) for the subsequent steps of measuring and calculating the hardness of the bottom rock. The first sampling step is essentially adaptive, since the results of rock hardness obtained at this step correspond to the bottomhole conditions of a particular well. In addition, since the determination of rock hardness is carried out in real well conditions, in which the rock properties are determined not only by hardness, but also by its filtration (porosity, permeability) properties, the result obtained is more consistent with rock drillability, and the process of determining these properties is scientific experiment. Moreover, the result of rock hardness is used to switch the drilling process to adaptive mode, i.e. the result is used as a feedback element in the intervals between the processes of measuring and determining the hardness of the rock.

Claims (4)

1. A method for automatically determining and recording the hardness of a face rock during a well drilling process, including impacting the rock and its destruction by a rotating and under load indenter, determining hardness indicators using the magnitude of the applied load and the indenter contact surface area, characterized in that the measurements they are carried out directly in the process of drilling in a differential form: mechanical speed or time of drilling duration of a certain inte shaft depth, measured WOB, aligned times or velocities are measured at the moment of equality of speeds or time load value on bit and determining rock hardness algorithm

,
Where $$P_{w.s.H_i}$$

- the hardness of the rock bottom (determined), corresponding to the subsequent measurement point for the depth of the well or time;
$$P_{w.s.H_i-\mathrm{one}}$$

- known rock hardness (set point), corresponding to the previous measurement point by the depth of the well or time, or selected, for example, according to the results of the experiment;
G _i - the load on the bit corresponding to the hardness of the rock and measured at the next measurement point;
G _i-1 - the load on the bit corresponding to the hardness of the rock measured at the previous measurement point. 2. The method according to claim 1, characterized in that to control the hardness of the rock, violated due to changing downhole conditions, the equality of the algorithm, an indicator term is introduced into it in the form
at $$\frac{{\vartheta }_i}{{\vartheta }_{i-\mathrm{one}}}$$

or $$\frac{T_i}{T_{i-\mathrm{one}}}$$

, and the algorithm itself will take the form

or

,
where ϑ _i is the mechanical drilling speed at the subsequent measurement point in depth;
ϑ _i-1 - mechanical drilling speed at the previous measurement point in depth;
T _i is the duration of the subsequent drilling interval;
T _i-1 - the duration of the previous drilling interval. 3. The method according to claim 2, characterized in that the restoration of the violated equality of the algorithm of claim 2 is carried out by changing the load on the bit - numerator of the algorithm until the ratio of speeds or times is equal to unity, ie indicator member of the algorithm, moreover, at the moment of equal relations to one, the value of the load on the bit - the numerator of the algorithm is measured. 4. A system for the automated determination and registration of hardness of a rock of a face while drilling a well, including sensors for load on the bit, movement of the tackle block, a winch and a GTI station with software that collects, processes, and records information, characterized in that a module is introduced into the system - a dispatcher performing consolidation at measurement points through a sampling step in depth or time of the indicated devices for solving the problem of determining and recording the hardness of a face rock, and the rest of the time, these devices operate as normal.

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