Uranium mine logging cable depth measuring method and device

Abstract

The application provides a kind of uranium mine logging cable depth measurement method and device, method includes: obtaining the multi-source real-time data in logging process;Based on multi-source real-time data, the logging depth is divided into a plurality of continuous depth intervals;Select multiple measuring points in each depth interval, the local light pulse coefficient K corresponding to each depth interval is calculated by using grating ruler-encoder joint calibration strategy i ;The encoder pulse number P corresponding to the i-th depth interval is obtained i , the actual depth D of the i-th depth interval is calculated i ;Accumulate to calculate actual total depth D.The application significantly improves the accuracy and reliability of uranium mine logging cable depth measurement by fusing multi-source real-time data and using adaptive interval division strategy and grating ruler-encoder joint calibration method.The method can effectively overcome the nonlinear error caused by cable stretching, depth measurement wheel slipping and other factors of traditional encoder, and avoid the cumulative deviation caused by fixed coefficient of full well depth.

Description

Technical Field

[0001] This invention relates to the field of logging technology for uranium geological exploration, and in particular to a method and device for measuring the depth of uranium logging cables. Background Technology

[0002] In uranium exploration and mining, well logging technology is a crucial means of obtaining information on physical parameters of underground rock formations, such as radioactivity, density, and resistivity. By lowering logging instruments into the borehole and continuously recording formation responses along the well depth, key information is provided for uranium resource reserve assessment, ore body spatial distribution analysis, and mining scheme design. Cable depth measurement, as a core component of well logging operations, directly determines the accuracy of rock formation depth positioning, thus affecting the reliability of subsequent reserve calculations, inter-well comparisons, and mining decisions. Especially in uranium mining, ore bodies often occur in layered or lenticular formations; accumulated depth positioning errors can lead to misjudgment of ore body boundaries, resulting in resource waste or mining risks.

[0003] Currently, traditional cable depth measurement methods primarily rely on encoders mounted on cable winches. These encoders rotate as the cable is wound up or down, recording the number of pulses generated per unit time to calculate the linear displacement of the cable and thus obtain the real-time depth of the logging instrument. This indirect measurement method based on encoder pulse counting can meet basic requirements under ideal conditions. However, the actual downhole logging environment is extremely complex; cables are typically hundreds or even thousands of meters long and are subject to interference from multiple factors during operation, leading to inaccurate measurement results. Summary of the Invention

[0004] In view of this, embodiments of the present invention provide a method and apparatus for measuring the depth of uranium mine logging cables, in order to eliminate or improve one or more defects existing in the prior art.

[0005] One aspect of the present invention provides a method for measuring the depth of a logging cable in uranium mines. The method includes the following steps: acquiring multi-source real-time data during the logging process, wherein the multi-source real-time data includes at least one or more of cable tension, natural gamma logging values, and cable motion acceleration. Based on the multi-source real-time data, an adaptive interval partitioning strategy is adopted to divide the logging depth into multiple continuous depth intervals; the adaptive interval partitioning strategy includes: when the change characteristics of any of the multi-source real-time data meet the preset interval boundary triggering conditions, a new depth interval boundary is automatically partitioned at the current depth position; Multiple measurement points are selected within each depth interval, and the local optical pulse coefficient K corresponding to each depth interval is calculated based on the measurement points using a joint calibration strategy of grating ruler and encoder. i ; Obtain the number of encoder pulses P corresponding to the cable moving from the starting position to the ending position in the i-th depth interval. i Calculate the actual depth D of the i-th depth interval. i ; Calculate the actual total depth D = D1 + D2 + ... + D i +……+D m , where m is the total number of depth intervals.

[0006] In some embodiments of the present invention, the grating ruler-encoder joint calibration strategy includes: when the starting depth of each measuring point is reached, controlling the cable winch to stop, fixing the cable to the reading head at the starting position of the grating ruler, so that the reading head moves synchronously with the cable; controlling the cable to lower or raise so that the reading head moves synchronously with the cable for a set distance, the set distance being less than the measuring range of the grating ruler; releasing the cable from the grating ruler reading head; and controlling the reading head to reset to the starting position. For each measuring point, the distance the data acquisition head moves synchronously with the cable is recorded as the actual displacement l of the grating ruler. i The number of encoder pulses p corresponding to the distance the cable moves li is collected. i ; Calculate the local optical pulse coefficient K of the depth measuring wheel for each depth interval. i , Where n is the number of measurement points within this depth range.

[0007] In some embodiments of the present invention, the preset interval boundary triggering condition includes: when the absolute value of the cable tension gradient exceeds a first preset threshold, a new depth interval boundary is defined at the current depth position.

[0008] In some embodiments of the present invention, the preset interval boundary triggering condition includes: when the local rate of change of the natural gamma logging value exceeds a second preset threshold, a new depth interval boundary is defined at the current depth position.

[0009] In some embodiments of the present invention, the preset interval boundary triggering condition includes: when the absolute value of the cable motion acceleration exceeds a third preset threshold, a new depth interval boundary is defined at the current depth position.

[0010] In some embodiments of the present invention, when the multi-source real-time data includes at least the cable tension, the step of selecting multiple measuring points in each depth interval includes: The cable tension T (h) is collected in real time. Calculate the tension gradient: In the depth range (h) start h end Within this range, define the measurement point density weights for tension contribution: in, These are preset coefficients; right Integrate within the depth interval and divide each measurement point according to the equal integral value.

[0011] In some embodiments of the present invention, when the multi-source real-time data includes at least the natural gamma logging value, the step of selecting multiple measuring points within each depth interval includes: Obtain the natural gamma curve GR(h); Calculate the rate of change of natural gamma logging values: Set measurement points at locations where the rate of change of natural gamma logging values ​​exceeds the fourth preset threshold.

[0012] In some embodiments of the present invention, when the multi-source real-time data includes at least the cable motion acceleration, the step of selecting multiple measuring points in each depth interval includes: Acquire cable acceleration signals and generate cable motion acceleration curve a(h); Take the absolute value of acceleration As a dynamic disturbance indicator; When the dynamic disturbance index is greater than the fifth preset threshold, measuring points are set at the depth position and at the first preset distances above and below it.

[0013] In some embodiments of the present invention, the step of selecting multiple measuring points in each depth interval includes: setting multiple measuring points at a second predetermined distance at the end of the depth interval, or setting multiple measuring points evenly at a third predetermined distance in the depth interval.

[0014] Another aspect of the present invention provides a uranium ore logging cable depth measurement device for performing the aforementioned uranium ore logging cable depth measurement method, the device comprising: A cable winch, comprising a depth measuring wheel, an encoder, a tension sensor, and an acceleration acquisition module, wherein a probe is connected to the cable end extending from the cable winch, and a gamma detection module is integrated on the probe; the tension sensor is used to acquire cable tension, and the acceleration acquisition module is used to acquire cable motion acceleration; A grating ruler calibration mechanism, comprising a grating ruler, a grating ruler fixing mechanism, a reading head reset mechanism, a pressure plate, and a pressure plate switching mechanism; The length direction of the grating ruler is parallel to the extension direction of the straight section of the cable above the ground; The grating ruler fixing mechanism is fixedly connected to the grating ruler and the cable winch respectively to keep the position of the grating ruler stable; The fixed end of the reading head reset mechanism is fixedly connected to the ground or the scale grating of the grating ruler. The movement trajectory of the moving end of the reading head reset mechanism is parallel to the length direction of the grating ruler. The moving end of the reading head reset mechanism is used to drive the reading head to reset. The pressure plate is mounted on the reading head of the grating ruler. One side of the pressure plate is hinged to the top of the reading head via a hinge, and the other side of the pressure plate is magnetically fixed to the reading head in an openable and closable manner. The pressure plate is used to press the cable onto the reading head when closed, so that the reading head and the cable can move synchronously. The pressure plate switch mechanism is controlled by the control signal of the processor module and is used to drive the pressure plate to press or release the cable; The data acquisition module is used to acquire in real time the depth data displayed by the cable winch, the number of encoder pulses, cable tension, cable motion acceleration, natural gamma logging values, and the displacement of the grating ruler reading head; The depth interval division module is communicatively connected to the data acquisition module and is used to divide the logging depth into multiple continuous depth intervals based on the acquired multi-source real-time data and an adaptive interval division strategy. The measurement point selection module is communicatively connected to the depth interval division module and is used to select multiple measurement points in each depth interval. The processor module is connected to the cable winch, the pressure plate switch mechanism, the data acquisition module, the depth interval division module, and the measurement point selection module, respectively. The processor module is configured as follows: Based on the measurement point position determined by the measurement point selection module, the cable winch is controlled to stop, and a clamping command is sent to the pressure plate switch mechanism, so that the pressure plate clamps the cable onto the reading head; The cable winch is controlled to lower or raise the cable by a set distance, while the actual displacement of the grating ruler is recorded by the data acquisition module. i and the corresponding encoder pulse number p i ; The pressure plate switch mechanism is controlled to release the cable, and the reading head reset mechanism is controlled to drive the reading head to reset to the starting position; Based on multiple (l) samples collected within the i-th depth interval i p i Yes, calculate the local optical pulse coefficient K for this depth range. i ; Obtain the number of encoder pulses p corresponding to the cable moving from the starting position to the ending position in the i-th depth interval. i Calculate the actual depth D of the i-th depth interval. i ; Calculate the actual total depth D = D1 + D2 + ... + D i +……+D m , where m is the total number of depth intervals.

[0015] The uranium mine logging cable depth measurement method and device of this invention significantly improves the accuracy and reliability of uranium mine logging cable depth measurement by integrating multi-source real-time data such as cable tension, natural gamma logging values, and acceleration, and by employing an adaptive interval division strategy and a grating ruler-encoder joint calibration method. This method effectively overcomes the nonlinear errors caused by cable tension and depth measurement wheel slippage in traditional encoders. It uses a high-precision grating ruler to calibrate and calculate the optical pulse coefficient for each depth interval, avoiding the cumulative deviation caused by a fixed coefficient across the entire well depth. Simultaneously, the adaptive division can respond in real-time to changes in downhole physical parameters, reducing resource misjudgment and mining risks caused by depth errors. Furthermore, this scheme is easy to implement in engineering, has operational flexibility, and provides high-precision, highly adaptable depth positioning support for uranium reserve assessment and mining design.

[0016] Additional advantages, objects, and features of the invention will be set forth in part in the description which follows, and will also become apparent in part to those skilled in the art upon studying the description, or may be learned by practice of the invention. The objects and other advantages of the invention can be realized and obtained by means of the structures specifically pointed out in the description and drawings.

[0017] Those skilled in the art will understand that the objectives and advantages achievable with the present invention are not limited to those specifically described above, and that the above and other objectives achievable with the present invention will become clearer from the following detailed description. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, are not intended to limit the scope of the invention. The components in the drawings are not drawn to scale but are merely illustrative of the principles of the invention. For ease of illustration and description of certain parts of the invention, corresponding portions in the drawings may be enlarged, i.e., may appear larger relative to other components in an exemplary device actually manufactured according to the invention.

[0019] Figure 1 This is a flowchart of a method for measuring the depth of a uranium ore logging cable in one embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of the structure of a uranium mine logging cable depth measuring device in one embodiment of the present invention.

[0021] Reference numerals: 1. Grating ruler; 11. Reading head; 12. Scale grating; 2. First connecting piece; 3. Second connecting piece; 41. Cylinder; 42. Push plate; 5. Pressure plate; 61. Second pulley; 62. Tension sensor; 7. Probe; 8. Cable winch; 81. Cable; 91. First pulley. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the embodiments and accompanying drawings. Here, the illustrative embodiments and descriptions of this invention are used to explain the invention, but are not intended to limit the invention.

[0023] It should also be noted that, in order to avoid obscuring the invention with unnecessary details, only the structures and / or processing steps closely related to the solution according to the invention are shown in the accompanying drawings, while other details that are not closely related to the invention are omitted.

[0024] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, element, step, or component, but does not exclude the presence or addition of one or more other features, elements, steps, or components.

[0025] It should also be noted that, unless otherwise specified, the term "connection" in this article can refer not only to a direct connection, but also to an indirect connection involving an intermediary.

[0026] In the following description, embodiments of the invention will be illustrated with reference to the accompanying drawings. In the drawings, the same reference numerals represent the same or similar parts, or the same or similar steps.

[0027] Reference Figure 1 This invention provides a method for measuring the depth of a uranium mine logging cable. The method includes the following steps: S1, acquiring multi-source real-time data during the logging process. The multi-source real-time data includes at least one or more of cable tension, natural gamma logging values, and cable motion acceleration. The multi-source real-time data can be selected as cable tension, natural gamma logging values, or cable motion acceleration. The multi-source real-time data can also be selected as a combination of any two of the above three types of data. The multi-source real-time data can also include the above three types of data simultaneously.

[0028] Research indicates that cable tension, natural gamma logging values, and cable acceleration are significant causes of measurement errors, as detailed below: During the movement of the cable inside the well, changes in tension cause variations in the slip ratio between the depth measuring wheel and the cable, thus affecting the encoder pulses and the depth conversion coefficient K. i To ensure stability, this embodiment uses tension as the basis for dividing depth intervals, thus achieving targeted zoning compensation for error sources. The physical properties of uranium ore layers and non-ore layers differ greatly. At the boundary of the ore layer, conditions such as cable stress and well fluid friction may change abruptly, affecting the accuracy of depth measurement. Therefore, in this embodiment, natural gamma logging values ​​can also be used as the basis for dividing depth intervals, which can improve the accuracy of depth measurement in ore layer sections. Changes in cable movement speed (such as acceleration, deceleration, and constant speed sections), especially at points of sudden speed change, can easily cause slippage between the depth measuring wheel and the cable. In practical applications, a cable winch can be used to control the cable's descent at a constant speed. However, due to the influence of fluids and sediment within the logging well on the probe, it is difficult to maintain a constant speed, resulting in speed variations in the cable. This embodiment uses the motion state as a dynamic basis for interval division, achieving refined depth compensation under unsteady conditions.

[0029] It should be noted that when multi-source real-time data includes two or more types of data, overlapping depth intervals defined by different real-time data should be considered as a new depth interval. For example, if the depth intervals defined by cable tension are 0-30m, 30m-50m, and 50m-100m, and the depth intervals defined by natural gamma logging values ​​are 0-80m and 80m-100m, then the depth intervals defined by these two types of data should be considered as 0-30m, 30m-50m, 50m-80m, and 80m-100m.

[0030] S2. Based on multi-source real-time data, an adaptive interval partitioning strategy is adopted to divide the logging depth into multiple continuous depth intervals. The adaptive interval partitioning strategy includes: when the change characteristics of any multi-source real-time data meet the preset interval boundary triggering conditions, a new depth interval boundary is automatically partitioned at the current depth position.

[0031] This embodiment employs an adaptive interval division strategy based on multi-source real-time data (cable tension, natural gamma logging values, cable motion acceleration, etc.) to detect changes in physical parameters within the wellbore in real time. When any data change triggers a boundary condition, a new depth interval is automatically defined, thus segmenting the logging process. This method avoids the cumulative error caused by using a fixed optical pulse coefficient across the entire well depth and effectively captures subtle depth changes at the orebody boundary.

[0032] S3. Select multiple measurement points within each depth interval, and calculate the local optical pulse coefficient K corresponding to each depth interval based on the measurement points using a joint calibration strategy of grating ruler and encoder. iThe grating ruler-encoder joint calibration strategy allows for local calibration of the encoder within each depth interval using high-precision grating ruler displacement measurements, enabling the calculation of the accurate local optical pulse coefficient K. i This effectively overcomes the nonlinear error between encoder pulses and actual displacement caused by factors such as cable stretching, wear, pulley slippage, and different accelerations in traditional methods, making the depth calculation of each interval more accurate.

[0033] S4. Obtain the number of encoder pulses P corresponding to the cable moving from the starting position to the ending position in the i-th depth interval. i Calculate the actual depth D of the i-th depth interval. i ;D i The calculation formula is as follows: S5. Calculate the actual total depth D = D1 + D2 + ... + D i +……+D m , where m is the total number of depth intervals.

[0034] This embodiment significantly improves the accuracy and reliability of uranium mine logging cable depth measurement by integrating multi-source real-time data such as cable tension, natural gamma logging values, and acceleration, and employing an adaptive interval division strategy and a grating ruler-encoder joint calibration method. This method effectively overcomes the nonlinear errors caused by cable tension and depth measuring wheel slippage in traditional encoders. It uses a high-precision grating ruler to calibrate and calculate the optical pulse coefficient for each depth interval, avoiding the cumulative deviation caused by a fixed coefficient across the entire well depth. Simultaneously, the adaptive division can respond in real-time to changes in downhole physical parameters, reducing resource misjudgment and mining risks caused by depth errors. Furthermore, this scheme is easy to implement in engineering, offers operational flexibility, and provides high-precision, highly adaptable depth positioning support for uranium reserve assessment and mining design.

[0035] In some embodiments, the grating ruler-encoder joint calibration strategy includes: when the starting depth of each measuring point is reached, controlling the cable winch to stop, fixing the cable to the reading head at the starting position of the grating ruler, so that the reading head moves synchronously with the cable; controlling the cable to lower or raise so that the reading head moves synchronously with the cable a set distance, the set distance being less than the measuring range of the grating ruler; releasing the cable from the binding of the cable to the grating ruler reading head; controlling the reading head to reset to the starting position; for each measuring point, collecting the distance that the reading head moves synchronously with the cable and recording it as the actual displacement l of the grating ruler. i ;Collection cable movement l i The distance corresponds to the number of encoder pulses p i ; Calculate the local optical pulse coefficient K of the depth measuring wheel corresponding to each depth interval. i K i The calculation formula is as follows: Where n represents the number of measurement points within that depth range. All the above operational steps can be implemented automatically through mechanical structures or control modules, or they can be implemented manually by the operator. It is important to note that for the data collected at each measurement point, significantly discrete data needs to be removed.

[0036] Referring to the table below, in one specific embodiment, the original optical pulse coefficient of the cable winch is 5510. In this depth measurement, four depth intervals were divided: 0-1m, 1m-100m, 100m-200m, and 200m-300m. Three measuring points were selected for each depth interval. Through the aforementioned K... i The calculation formula yielded local optical pulse coefficients of 5755, 5538, 5497, and 5472 for each depth range. The actual distances for the 0-1m depth range were calculated to be 0.987m, 1m-100m to 98.499m, 100m-200m to 100.236m, and 200m-300m to 100.694m. The actual depth at 300m, as displayed by the cable winch, was the sum of the actual distances for all the above depth ranges, totaling 300.416m. To simplify the calculation steps, K i Alternatively, the average value of the actual optical pulse coefficients corresponding to each measurement point in each depth range can be taken.

[0037] In the above embodiment of the grating scale-encoder joint calibration strategy, short-distance synchronous movement and reading head reset operations are adopted, which not only ensures calibration accuracy but also avoids dependence on long-stroke grating scales, reducing equipment costs and installation difficulty, and facilitating the upgrading of existing logging winch systems. Simultaneously, using multiple measuring points to calculate the local optical pulse coefficient in a weighted least squares form can smoothly couple measurement noise, thus obtaining the local optical pulse coefficient K. i It is more representative and scientific.

[0038] In some embodiments, the preset interval boundary triggering condition includes: when the absolute value of the cable tension gradient exceeds a first preset threshold, a new depth interval boundary is defined at the current depth position. When the absolute value of the cable tension gradient with depth exceeds the first preset threshold, it indicates that the tension or resistance of the cable has changed abruptly, which usually corresponds to a sudden increase in friction on the well wall, a bending section, or a jamming point. At this time, a new depth interval is automatically defined.

[0039] For example, the first threshold is set to 20 N / m. During well logging, if the cable tension decreases from 1500 N to 1200 N and the depth changes by 10 m, the absolute value of the gradient is (1500-1200) / 10 = 30 N / m > 20 N / m, which triggers the depth boundary delineation.

[0040] In some embodiments, the preset interval boundary triggering conditions include: when the local rate of change of the natural gamma logging value exceeds a second preset threshold, a new depth interval boundary is delineated at the current depth location. Natural gamma logging values ​​are extremely sensitive to changes in uranium mineralization layers and surrounding rock lithology. When the local rate of change exceeds the second preset threshold, it indicates that the logging instrument is traversing radioactive abrupt change areas such as ore body boundaries. Delineating interval boundaries at these locations ensures that the radioactive characteristics within each depth interval remain relatively stable, thereby avoiding complex coupling effects such as cable weight distribution and frictional changes caused by lithological variations in subsequent depth calibration, and improving the accuracy of ore body positioning.

[0041] For example, the second threshold is set to 50 API / m. If the gamma logging value jumps from 200 API to 220 API within a 0.2m depth interval, the rate of change is (220-200) / 0.2=100 API / m>50 API / m, which triggers a new boundary delineation.

[0042] In some embodiments, the preset interval boundary triggering conditions include: when the absolute value of the cable's motion acceleration exceeds a third preset threshold, a new depth interval boundary is defined at the current depth position. The absolute value of the cable's motion acceleration exceeding the third preset threshold typically indicates non-steady-state conditions such as winch start / stop, sudden speed changes, or the cable being momentarily jammed and then released. In this case, the ratio between the encoder pulses and the actual cable displacement may be distorted due to transient elastic fluctuations. Defining a new boundary can separate drastically dynamically changing segments, preventing transient disturbances from affecting steady-state calibration results, and also facilitates the identification of abnormal conditions and the initiation of corresponding data correction or repetitive measurement procedures.

[0043] For example, the third threshold is set to 0.5 m / s. 2 If the acceleration during the cable lowering process is 0.1 m / s² 2 It suddenly increased to 0.8 m / s 2 If the absolute value is 0.7 > 0.5, then boundary division is triggered, and a new depth interval is automatically started at the acceleration mutation point.

[0044] In some embodiments, where the multi-source real-time data includes at least cable tension, the step of selecting multiple measurement points within each depth interval includes: Real-time acquisition of cable tension T (h); Calculate the tension gradient: In the depth range (h) start h end Within this range, define the measurement point density weights for tension contribution: in, These are preset coefficients; right Integrate within the depth range and divide each measuring point according to the equal integral value. In the above embodiment, a large cable tension gradient indicates drastic changes in friction or jamming between the cable and the well wall or depth measuring wheel. The slip ratio may change abruptly at this location, thus requiring more frequent calibration.

[0045] In some embodiments, where the multi-source real-time data includes at least natural gamma logging values, the step of selecting multiple measurement points within each depth interval includes: Obtain the natural gamma logging curve GR(h); Calculate the rate of change of natural gamma logging values: A measuring point is set at a location where the rate of change of the natural gamma logging value is greater than the fourth set threshold, and the fourth set threshold is less than the second set threshold.

[0046] Natural gamma logging values ​​reflect changes in uranium ore layers and surrounding rocks. At ore layer boundaries and within high-gamma ore layers, higher depth measurement accuracy is required, necessitating more intensive calibration.

[0047] In some embodiments, when the multi-source real-time data includes at least cable motion acceleration, the step of selecting multiple measurement points within each depth interval includes: Acquire cable acceleration signals and generate cable motion acceleration curve a(h); Take the absolute value of acceleration As a dynamic disturbance indicator; When the dynamic disturbance index exceeds the fifth set threshold (the fifth set threshold is less than the third set threshold), measurement points are set at this depth position and at the first set distances above and below it. A large absolute value of acceleration indicates rapid velocity changes (such as during the start-up, stop, and speed change of the cable). Transient slippage or elastic deformation may occur between the cable and the depth measuring wheel, requiring denser calibration before and after such dynamic points.

[0048] In some embodiments, the step of selecting multiple measuring points in each depth range includes: setting multiple measuring points at a second predetermined distance at the end of the depth range. The second predetermined distance can be a distance smaller than the range of the grating ruler, such as 0.8m or 0.9m. The second predetermined distance can be different values ​​in the same depth range. For ease of operation, the second predetermined distance can be the actual displacement value of the reading head of the grating ruler.

[0049] In some embodiments, multiple measuring points are evenly distributed at third predetermined intervals within the depth range. This embodiment is a uniformly distributed point selection method, where 3-8 measuring points can be selected within the same depth range, with the same distance between each measuring point. Both of these measuring point setting methods are simple, convenient, computationally efficient, and easy to implement.

[0050] In the method described above, the cable needs to be lowered twice during well logging. The first step involves dividing the well into different depth intervals, and the second step involves selecting measurement points for each depth interval and calculating the local optical pulse coefficient K. i The actual depth values ​​at each location are then accumulated. Alternatively, the depth can be obtained using the following fusion formula during the measurement point acquisition step.

[0051] (1) For the depth interval (H0, H1), define the comprehensive measurement point density factor for each depth point h: in, , and This is an adjustable coefficient (the default value is 1). This represents the derivative with respect to depth.

[0052] (2) Calculate the cumulative density function: Here, ξ is the depth variable used in the integration process, with values ​​ranging from H0 to h.

[0053] (3) Set the total number of measuring points N, which can be determined based on the average density of the interval or a fixed number. Then the depth of the i-th measuring point satisfies: That is, equal division of cumulative density integral to realize the distribution of measuring points and Proportional.

[0054] The above measurement point division steps comprehensively consider the effects of cable tension, natural gamma logging values, and acceleration, proposing a novel method for measurement point selection that makes the selection more scientific and yields a higher local optical pulse coefficient K. i More accurate.

[0055] To simplify the calculation process and reduce the amount of data processing, the starting depth data D1 of the cable when the reading head is at the starting position can be collected within each depth interval. i The cable's endpoint depth data D2 when the reading head is at the endpoint position. i D1 i and D2 i These are all display values ​​from the cable winch.

[0056] Calculate depth measurement error Δ iand relative error δ i Among them, the depth measurement error Δ i =|L i -(D2 i -D1 i )|, relative error δ i =Δ i / L i ×100%; If the relative error is ≤0.1%, the depth data displayed by the cable winch shall be taken as the actual depth D. i ; If the relative error is greater than 0.1%, then calculate the local optical pulse coefficient K for that depth range. i .

[0057] Reference Figure 2 The present invention also provides a uranium mine logging cable depth measurement device for performing a uranium mine logging cable depth measurement method. The device includes a cable winch 8, a grating ruler calibration mechanism, a data acquisition module, a depth interval division module, a measurement point selection module, and a processor module.

[0058] The cable winch 8 includes a depth measuring wheel, an encoder, a tension sensor, and an acceleration acquisition module (not shown in the figure). The cable 81 extending from the winch 8 is connected to a probe 7, which integrates a gamma detection module. The tension sensor collects cable tension, and the acceleration acquisition module collects cable acceleration. The cable 81 passes over the bottom of the first pulley 91 and the top of the second pulley 61 before entering the logging well. A tension sensor 62 can be installed on the mounting bracket of the second pulley 61 to acquire the cable tension value. The above embodiment provides two tension acquisition mechanisms: the tension sensor in the cable winch 8 and the tension sensor on the second pulley mounting bracket. Both sensors can indirectly acquire the cable tension value; either one can be selected.

[0059] The grating ruler calibration mechanism includes a grating ruler 1, a grating ruler fixing mechanism, a reading head reset mechanism, a pressure plate 5, and a pressure plate switch mechanism.

[0060] The length direction of the grating ruler 1 is parallel to the extension direction of the straight section of the cable above the ground. The grating ruler 1 includes a scale grating 12 and a reading head 11. A guide wheel structure may also be provided on the scale grating 12 for guiding the cable.

[0061] The grating ruler fixing mechanism is fixedly connected to the grating ruler 1 and the cable winch 8 respectively to keep the position of the grating ruler 1 stable. The grating ruler fixing mechanism includes a first connecting piece 2 and a second connecting piece 3. One end of the first connecting piece 2 is fixedly connected to the cable winch 8, and one end of the second connecting piece 3 is fixedly connected to the grating ruler. The ends of the first connecting piece 2 and the second connecting piece 3 that are close to each other are connected, and their included angle is adjustable so that the grating ruler 1 can be set to a state parallel to the cable.

[0062] The fixed end of the reading head reset mechanism is fixedly connected to the ground or the scale grating of the grating ruler. The movement trajectory of the moving end of the reading head reset mechanism is parallel to the length direction of the grating ruler 1. The moving end of the reading head reset mechanism is used to drive the reading head to reset. Optionally, the reading head reset mechanism may include a cylinder 41 and a push plate 42. The cylinder 41 is fixedly installed at the end of the grating ruler, and the extension and retraction direction of the cylinder 41 is parallel to the movement direction of the reading head. The push plate 42 is fixedly installed at the movable end of the cylinder 41, and the extension of the cylinder can push the reading head to reset via the push plate 42.

[0063] In the above embodiment, the pressure plate 5 is installed on the reading head of the grating ruler 1. One side of the pressure plate 5 is hinged to the top of the reading head by a hinge, and the other side of the pressure plate 5 is magnetically fixed to the reading head in an openable and closable manner. The pressure plate 5 is used to press the cable onto the reading head when closed, so that the reading head and the cable can move synchronously.

[0064] The pressure plate switch mechanism is controlled by the processor module's control signal to drive the pressure plate 5 to press or release the cable. The pressure plate switch mechanism can optionally consist of two electric push rods, one for pushing the pressure plate outwards and the other for pushing it closed. In this case, it is necessary to control the free rotation angle of the pressure plate 5, keeping it as small as possible, for example, 10 to 30 degrees, to facilitate the setting of the two electric push rods. Alternatively, the pressure plate switch mechanism can be a combination of a spring and an electromagnet. The electromagnets are installed on the side of the pressure plate away from the hinge and on the side of the reading head away from the hinge, with the two electromagnets positioned corresponding to each other. When energized, the electromagnets attract each other, causing the pressure plate to press against the reading head. A spring is installed between the pressure plate and the reading head. When the electromagnets are de-energized, the spring can lift the pressure plate, causing it to rotate a small angle around the hinge, just enough to prevent the cable from being squeezed by the pressure plate.

[0065] The data acquisition module is used to acquire in real time the depth data displayed by the cable winch, the number of encoder pulses, cable tension, cable motion acceleration, natural gamma logging values, and the displacement of the grating ruler reading head.

[0066] The depth interval division module communicates with the data acquisition module and is used to divide the logging depth into multiple continuous depth intervals based on the acquired multi-source real-time data and an adaptive interval division strategy. The measurement point selection module communicates with the depth interval division module and is used to select multiple measurement points within each depth interval. The processor module is connected to the cable winch, the pressure plate switch mechanism, the data acquisition module, the depth interval division module, and the measurement point selection module, respectively. The processor module is configured as follows: Based on the measurement point position determined by the measurement point selection module, the control cable winch stops and sends a clamping command to the pressure plate switch mechanism, so that the pressure plate 5 clamps the cable onto the reading head; The control cable winch lowers or raises the cable by a set distance, while the actual displacement of the grating ruler is recorded by the data acquisition module. i and the corresponding encoder pulse number p i ; The control plate switch mechanism releases the cable and controls the reading head reset mechanism to reset the reading head to the starting position; Based on multiple (l) samples collected within the i-th depth interval i p i Yes, calculate the local optical pulse coefficient K for this depth range. i ; Obtain the number of encoder pulses P corresponding to the cable moving from the starting position to the ending position in the i-th depth interval. i Calculate the actual depth D of the i-th depth interval. i ; Calculate the actual total depth D = D1 + D2 + ... + D i +……+D m , where m is the total number of depth intervals.

[0067] The data acquisition module, depth interval division module, measurement point selection module, and processor module in the above embodiments can all be integrated into a computer and automatically controlled by set software or control programs.

[0068] It should be clarified that the present invention is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present invention is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of the present invention.

[0069] In this invention, features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, and / or combined with or in place of features of other embodiments.

[0070] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, various modifications and variations of the embodiments of the present invention are possible. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for measuring the depth of a uranium mine logging cable, characterized in that, The method includes the following steps: acquiring multi-source real-time data during the logging process, wherein the multi-source real-time data includes at least one or more of cable tension, natural gamma logging values, and cable motion acceleration; Based on the multi-source real-time data, an adaptive interval partitioning strategy is adopted to divide the logging depth into multiple continuous depth intervals; the adaptive interval partitioning strategy includes: when the change characteristics of any of the multi-source real-time data meet the preset interval boundary triggering conditions, a new depth interval boundary is automatically partitioned at the current depth position; Multiple measurement points are selected within each depth interval, and the local optical pulse coefficient K corresponding to each depth interval is calculated based on these measurement points using a joint calibration strategy of grating ruler and encoder. i ; Obtain the number of encoder pulses Pi corresponding to the cable moving from the starting position to the ending position in the i-th depth interval, and calculate the actual depth D of the i-th depth interval. i ; Calculate the actual total depth D = D1 + D2 + ... + D i +……+D m , where m is the total number of depth intervals.

2. The method for measuring the depth of uranium mine logging cables according to claim 1, characterized in that, The grating ruler-encoder joint calibration strategy includes: when the starting depth of each measuring point is reached, the control cable winch stops, and the cable is fixed to the reading head at the starting position of the grating ruler, so that the reading head moves synchronously with the cable; the control cable is lowered or raised so that the reading head moves synchronously with the cable for a set distance, the set distance being less than the range of the grating ruler; the binding between the cable and the grating ruler reading head is released; and the control cable is reset to the starting position. For each measuring point, the distance the data acquisition head moves synchronously with the cable is recorded as the actual displacement l of the grating ruler. i ;Collection cable movement l i The distance corresponds to the number of encoder pulses p i ; Calculate the local optical pulse coefficient K of the depth measuring wheel for each depth interval. i , Where n is the number of measurement points within this depth range.

3. The method for measuring the depth of uranium mine logging cables according to claim 1, characterized in that, The preset interval boundary triggering conditions include: when the absolute value of the cable tension gradient exceeds a first preset threshold, a new depth interval boundary is defined at the current depth position.

4. The method for measuring the depth of uranium mine logging cables according to claim 1, characterized in that, The preset interval boundary triggering conditions include: when the local rate of change of the natural gamma logging value exceeds a second preset threshold, a new depth interval boundary is defined at the current depth position.

5. The method for measuring the depth of uranium mine logging cables according to claim 1, characterized in that, The preset interval boundary triggering conditions include: when the absolute value of the cable's motion acceleration exceeds a third preset threshold, a new depth interval boundary is defined at the current depth position.

6. The method for measuring the depth of uranium mine logging cables according to claim 1, characterized in that, When the multi-source real-time data includes at least the cable tension, the step of selecting multiple measuring points within each depth interval includes: The cable tension T (h) is collected in real time. Calculate the tension gradient: In the depth range (h) start h end Within this range, define the measurement point density weights for tension contribution: in, These are preset coefficients; right Integrate within the depth interval and divide each measurement point according to the equal integral value.

7. The method for measuring the depth of uranium mine logging cables according to claim 1, characterized in that, When the multi-source real-time data includes at least the natural gamma logging value, the step of selecting multiple measurement points within each depth interval includes: Obtain the natural gamma curve GR(h); Calculate the rate of change of natural gamma logging values: Set measurement points at locations where the rate of change of natural gamma logging values ​​exceeds the fourth preset threshold.

8. The method for measuring the depth of uranium mine logging cables according to claim 1, characterized in that, When the multi-source real-time data includes at least the cable motion acceleration, the step of selecting multiple measurement points within each depth interval includes: Acquire cable acceleration signals and generate cable motion acceleration curve a(h); Take the absolute value of acceleration As a dynamic disturbance indicator; When the dynamic disturbance index is greater than the fifth preset threshold, measuring points are set at the depth position and at the first preset distances above and below it.

9. The method for measuring the depth of uranium mine logging cables according to claim 1, characterized in that, The step of selecting multiple measuring points in each depth interval includes: setting multiple measuring points at a second predetermined distance at the end of the depth interval, or setting multiple measuring points evenly at a third predetermined distance in the depth interval.

10. A device for measuring the depth of a uranium ore logging cable, characterized in that, For performing the uranium ore logging cable depth measurement method as described in any one of claims 1-9, the apparatus comprises: A cable winch, comprising a depth measuring wheel, an encoder, a tension sensor, and an acceleration acquisition module, wherein a probe is connected to the cable end extending from the cable winch, and a gamma detection module is integrated on the probe; the tension sensor is used to acquire cable tension, and the acceleration acquisition module is used to acquire cable motion acceleration; The grating ruler calibration mechanism includes a grating ruler (1), a grating ruler fixing mechanism, a reading head reset mechanism, a pressure plate (5), and a pressure plate switch mechanism. The length direction of the grating ruler (1) is parallel to the extension direction of the straight section of the cable above the ground; The grating ruler fixing mechanism is fixedly connected to the grating ruler (1) and the cable winch respectively to keep the position of the grating ruler (1) stable; The fixed end of the reading head reset mechanism is fixedly connected to the ground or the scale grating of the grating ruler. The movement trajectory of the moving end of the reading head reset mechanism is parallel to the length direction of the grating ruler (1). The moving end of the reading head reset mechanism is used to drive the reading head to reset. The pressure plate (5) is installed on the reading head of the grating ruler (1). One side of the pressure plate (5) is hinged to the top of the reading head by a hinge, and the other side of the pressure plate (5) is magnetically fixed to the reading head in an openable and closable manner. The pressure plate (5) is used to press the cable onto the reading head when closed, so that the reading head and the cable can move synchronously. The pressure plate switch mechanism is controlled by the control signal of the processor module and is used to drive the pressure plate (5) to press or release the cable; The data acquisition module is used to acquire in real time the depth data displayed by the cable winch, the number of encoder pulses, cable tension, cable motion acceleration, natural gamma logging values, and the displacement of the grating ruler reading head; The depth interval division module is communicatively connected to the data acquisition module and is used to divide the logging depth into multiple continuous depth intervals based on the acquired multi-source real-time data and an adaptive interval division strategy. The measurement point selection module is communicatively connected to the depth interval division module and is used to select multiple measurement points within each depth interval. The processor module is connected to the cable winch, the pressure plate switch mechanism, the data acquisition module, the depth interval division module, and the measurement point selection module, respectively. The processor module is configured as follows: Based on the measurement point position determined by the measurement point selection module, the cable winch is controlled to stop, and a pressing command is sent to the pressure plate switch mechanism so that the pressure plate (5) presses the cable onto the reading head; The cable winch is controlled to lower or raise the cable by a set distance, while the actual displacement of the grating ruler is recorded by the data acquisition module. i and the corresponding encoder pulse number p i ; The pressure plate switch mechanism is controlled to release the cable, and the reading head reset mechanism is controlled to drive the reading head to reset to the starting position; Based on multiple (l) samples collected within the i-th depth interval i p i Yes, calculate the local optical pulse coefficient K for this depth range. i ; Obtain the number of encoder pulses P corresponding to the cable moving from the starting position to the ending position in the i-th depth interval. i Calculate the actual depth D of the i-th depth interval. i ; Calculate the actual total depth D = D1 + D2 + ... + D i +……+D m , where m is the total number of depth intervals.

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