Steel ladle refining monitoring device and method based on vibration measurement

Abstract

The invention discloses a steel ladle refining monitoring device and method based on vibration measurement. Vibration sensors are symmetrically installed, and a signal acquisition and analysis module and an information early warning display module are used for analyzing and extracting characteristic values of vibration signals; a sliding window method is adopted, whether stirring is uniform or not can be accurately judged in time through difference analysis of vibration amplitudes and dispersion degrees of different vibration sensors in different directions within window time, and the phenomenon that stirring is insufficient or excessive frequently occurs in a traditional experience stirring method, and resources are wasted is avoided. The vibration sensor is fixedly connected with the bottom of the steel ladle, the outer side of the steel ladle, a steel ladle hanging lug, an upper edge opening of the steel ladle or a trolley fixedly connected with the steel ladle; symmetrical installation comprises the step that the center axis of the steel ladle serves as the symmetry axis.

Description

Technical Field

[0001] The present invention relates to the technical field of steel smelting and control, and in particular to a ladle refining monitoring device and method based on vibration measurement. Background Art

[0002] Ladle degassing refining is the main method of off-furnace refining (also known as secondary steelmaking, referred to as ladle refining in this article). It is a process in which molten steel smelted in a roughing furnace (electric furnace and converter) is transferred to another high-temperature container (mainly a ladle) for refining. It is mainly classified into: (1) ladle treatment type: such as ladle argon blowing, ladle powder spraying and vacuum circulation degassing (RH); (2) ladle refining type, such as vacuum oxygen decarburization (VOD), argon oxygen decarburization (AOD), ladle refining (LF, ASEA-CKF, VAD, etc.). Gas agitation is used to improve mixing and promote chemical reactions, and the control of gas intensity (or flow rate, flow rate) and time has a great influence on the entire process.

[0003] Since the ladle refining process is carried out at high temperatures, it is difficult for general video image detection to obtain images that effectively reflect the stirring effect under high temperature conditions. Of course, even if on-site images can be obtained, it is difficult to extract information about the stirring effect. Currently, there is a lack of effective monitoring means and methods in the ladle refining process. The main method is to manually judge whether the stirring is uniform based on on-site operating experience. In fact, most of the time, the stirring effect is guaranteed by stirring for a sufficient time at an empirical stirring intensity. In other words, there is often an over-stirring state, which makes it difficult to improve the refining efficiency. Manual observation is required. If unqualified products are found in subsequent inspections, it will cause great losses. The products cast in the entire furnace (ladle) may become waste. Ladle degassing refining urgently needs a convenient and effective refining effect monitoring device and method. Summary of the Invention

[0004] The present invention realizes convenient and effective online monitoring of gas stirring effect through reasonable vibration sensor layout combined with signal acquisition and analysis.

[0005] To achieve the above-mentioned purpose, the technical solution of the present invention is to design a ladle refining monitoring device based on vibration measurement, wherein the monitoring device includes at least two vibration sensors that are symmetrical in distance and angle and are in the same installation plane, and a signal acquisition and analysis module electrically connected to the vibration sensor. The information warning display module is electrically connected to the signal acquisition and analysis module. The symmetrically installed vibration sensors are set to judge and analyze whether the vibration characteristic values ​​of the vibration sensors at the symmetrical positions of the ladle are consistent. Theoretically, if the stirring is uniform or nearly uniform, the vibration characteristic values ​​at the symmetrical positions should be basically consistent; the fixed installation positions of the vibration sensors include the bottom of the ladle, the outside of the ladle, the ladle ear, the upper edge of the ladle or the trolley fixed to the ladle; the symmetrical installation includes the central axis of the ladle as the symmetry axis, and the electrical connection includes a wired connection and / or a wireless connection.

[0006] The vibration sensor measures the vibration amount in at least one of the three directions of x, y, and z, and the vibration amount includes at least one of displacement, velocity, or acceleration.

[0007] Furthermore, the installation position of the vibration sensor on the trolley includes a support seat (generally a hanging ear support seat), or a support platform base or a support platform column, and the installation position can transmit the vibration caused by the stirring of the molten steel inside the ladle; the installation method includes threaded installation, magnetic base installation, glue installation or clip installation.

[0008] Furthermore, three vibration sensors are arranged equidistantly at intervals of 120 degrees in a circle in the same plane.

[0009] Furthermore, four vibration sensors are arranged circumferentially at equal intervals of 90 degrees in the same plane.

[0010] Furthermore, vibration sensors are symmetrically arranged in two or more different planes.

[0011] Furthermore, when the vibration sensor is arranged on the ladle (including the bottom of the ladle, the outside of the ladle, the ladle lug, and the upper edge of the ladle), the vibration sensor includes a wireless vibration sensor, which is connected to the signal acquisition and analysis module by radio, and the wireless connection is realized through a wireless routing relay unit.

[0012] Furthermore, when the vibration sensor is arranged on the trolley, the signal acquisition and analysis module includes an integrated data acquisition box, which includes a vibration collector, an industrial switching power supply and a circuit breaker.

[0013] On the other hand, a ladle refining monitoring method based on vibration measurement is characterized in that the ladle refining monitoring device based on the above-mentioned symmetrical arrangement of vibration sensors collects the vibration amount of the symmetrically installed vibration sensors within the window time (also called the window time). 、 ..., extract the first eigenvalue corresponding to the vibration amount 、 …and the second eigenvalue 、 …,in, is the sampling sequence number. The sampling period is determined by the vibration frequency and the characteristics of the sensor and the data acquisition instrument (data acquisition box). The first subscript of the vibration quantity and characteristic value identifies the vibration sensor number. The monitoring method includes monitoring method 1 or monitoring method 2. The monitoring method includes: if all the , j≠k (e.g. ), the ladle is considered to be stirred evenly, otherwise it needs to be stirred further, where is the first threshold.

[0014] The second monitoring method includes: if all the , j≠k (e.g. ), and satisfy all (like and etc.), the ladle is considered to be stirred evenly, otherwise it needs to be stirred further, among which, is the second threshold.

[0015] Furthermore, the first eigenvalue includes at least one of the mean, median, and norm; the second eigenvalue includes at least one of the variance (RMS, root mean square value), standard deviation, maximum value, minimum value, and extreme value difference, and the extreme value difference is the difference between the maximum value and the minimum value.

[0016] Furthermore, the lower limit of the window duration is not less than 3 longest vibration cycle durations, and the upper limit is not greater than the minimum lag duration.

[0017] Furthermore, the monitoring method includes a sliding window monitoring method, that is, the unit time window slides once, and the vibration amount and its characteristic value within the sliding window time length are analyzed and judged according to the monitoring method one or the monitoring method two; the unit time includes an integer number of seconds (such as every 1 second or every 2 seconds, etc.) or a unit time greater than or equal to the longest vibration period or greater than or equal to an integer multiple of the sampling period.

[0018] The advantages and beneficial effects of the present invention are as follows: the vibration measurement-based ladle refining monitoring device and method proposed in the present invention can timely and accurately determine whether the gas stirring during the ladle refining process is uniform, that is, whether the stirring effect is achieved, by analyzing the vibration quantity characteristics of symmetrically arranged vibration sensors; it is more reliable than the traditional method of using empirical flow rate and empirical stirring time, can adapt to different stirring environments and the requirements of different stirring processes, avoids unnecessary stirring or insufficient stirring, is more efficient, and has higher control accuracy for ladle refining; and different threshold parameters can be set for different refined products, that is, the requirements for the performance of the ladle refined product are reflected through the vibration threshold parameters, thereby further determining whether the stirring effect meets the requirements of the refined product by detecting the difference in vibration transmission. The application of the present invention can not only improve the stirring efficiency of ladle refining, but also reduce the scrap rate of refined products. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a structural diagram of a ladle refining monitoring device based on vibration measurement; Figure 2 It is a schematic diagram of the layout of ladle refining monitoring sensors.

[0020] In the figure: 1. Ladle; 2. Hanging lug; 3. Trolley; 4. Sensor; 5. Air blowing pipe; 6. Valve. DETAILED DESCRIPTION

[0021] The following embodiments are further described in conjunction with the accompanying drawings and examples. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0022] Theoretical analysis shows that vibration signals can effectively characterize gas stirring intensity, but since it is difficult to find the law between the two, practical engineering applications face difficulties.

[0023] While some research has explored the use of vibration measurement to monitor ladle stirring, this intensity is dependent on numerous factors, including ladle type (including lining), molten steel height (or weight), outlet shape, gas velocity and flow rate, sensor installation method and location, ambient vibration, additive type and addition rate, and other interfering factors. While the Ladle Response Value (LRV) can provide a good description of gas stirring, it lacks reliable information on whether the addition of additives and other ingredients ensures uniform mixing. Furthermore, these factors hinder the comparability of ladle response values ​​across time, location, and for different objects. Obtaining effective empirical data requires extensive experimentation, suffers from poor continuity, and changes in environmental conditions can affect the usability of these empirical data. Consequently, this technology remains at the laboratory research stage, with no practical monitoring devices or methods available for engineering applications.

[0024] Example 1: like Figures 1-2 As shown, the present invention is a ladle refining monitoring device based on vibration measurement, the monitoring device includes at least two vibration sensors that are symmetrical in distance and angle and are in the same installation plane, and a signal acquisition and analysis module electrically connected to the vibration sensors, and the information warning display module is electrically connected to the signal acquisition and analysis module. The symmetrically installed vibration sensors are set to judge and analyze whether the vibration characteristic values ​​of the vibration sensors at the symmetrical positions of the ladle are consistent. Theoretically, if the stirring is uniform or nearly uniform, the vibration characteristic values ​​at the symmetrical positions should be basically consistent; the fixed installation positions of the vibration sensors include the bottom of the ladle, the outside of the ladle, the ladle hanging ear, the upper edge of the ladle or the trolley fixed to the ladle. The specific installation position should be able to well transmit the vibration information of the molten steel inside the ladle, and can effectively avoid the influence of high temperature and splashing of the molten steel. The vibration sensors are symmetrically installed in the same plane mainly to facilitate analysis and judgment of the gas stirring effect; the symmetrical installation includes the central axis of the ladle as the symmetry axis, and the electrical connection includes wired connection and / or wireless connection. Since ladle refining is carried out in a high-temperature environment, general monitoring displays or warnings are located in a relatively safe and suitable environment at an appropriate distance. Taking into account the movable and transportable characteristics of the ladle being tested, the electrical connection between the information warning display module and the signal acquisition and analysis module generally adopts a wireless connection; the signal acquisition and analysis module analyzes and judges the received vibration sensor signal, and sends the analysis and judgment results to the information warning display module for display and emits an audible and visual warning signal and a prompt signal that the stirring is uniform. The information warning display module can be located together with the signal analysis function module (part of the signal acquisition and analysis module) on a remote terminal such as a server. In addition to the data acquisition function, the on-site data acquisition box can also be provided with corresponding simplified display and signal analysis functions. In short, the actual module division and configuration method can be determined according to actual needs.

[0025] The vibration sensor measures vibration in at least one of the three directions: x, y, and z (here x and y are horizontal, z is vertical). This vibration includes at least one of displacement, velocity, or acceleration. If only one is measured, vertical velocity (which can be obtained by integrating acceleration) is generally preferred. This is because vertical vibration velocity better reflects gas stirring intensity and is ideal as raw characteristic information. Experimental analysis has shown that the root mean square (RMS) of vertical velocity is the best characteristic for measuring stirring intensity caused by the blowing gas velocity within the ladle. Furthermore, the vertical vibration velocity is relatively high in magnitude, requiring less precision, and providing more accurate differential judgment.

[0026] The vibration sensor and signal acquisition and analysis module can be designed as an integrated whole, or integrated with some functional units of the signal acquisition and analysis module to form a sensor hardware system, including five functional units such as signal perception, signal conditioning, signal acquisition, data analysis, and data upload, or divided into power supply, signal conditioning, signal acquisition, ARM MCU data acquisition and processing system, wireless data transceiver and other units. In short, the specific software and hardware function allocation and combination are diverse and can be determined according to the specific application environment requirements.

[0027] Preferably, the installation position of the vibration sensor on the trolley includes a support seat (generally a hanging ear support seat), or a support platform base or a support platform column. The installation position can transmit the vibration caused by the stirring of the molten steel inside the ladle. In short, the selection of the installation position should ensure that the high temperature of the molten steel has little effect on the vibration sensor, or it can be ignored. On the other hand, it should ensure that the vibration of the stirring of the ladle can be transmitted to the vibration sensor with little or almost no attenuation. Thirdly, the symmetry of all installation points must be ensured. If two sensors are arranged, it is advisable to install them on the support seat of the hanging ear. The installation methods include threaded installation, magnetic base installation, glue installation or clip-on installation.

[0028] Preferably, when the vibration sensor is arranged on the ladle (including the bottom of the ladle, the outside of the ladle, the ladle lug, and the upper edge of the ladle), the vibration sensor includes a wireless vibration sensor, which is connected to the signal acquisition and analysis module by radio. The wireless connection is realized through a wireless routing relay unit, and the wireless routing relay unit includes a wireless receiving router, a 24V switching power supply and a circuit breaker.

[0029] Preferably, the signal acquisition and analysis module includes an integrated data acquisition box, which includes a vibration collector, an industrial switching power supply, and a circuit breaker. The vibration sensor includes a three-axis acceleration sensor.

[0030] In this embodiment, one vibration sensor is set on each side of the two hanging ears of the ladle. The wireless vibration sensor model is XDG2900 and is wirelessly connected to the signal acquisition and analysis module; one sensor is installed symmetrically on the base of the trolley and in the direction of the hanging ears. The three-axis acceleration sensor model is XDG1283 and is wired to the signal acquisition and analysis module, totaling 4 and 2 groups of symmetrical sensors; the vibration sensor simultaneously measures the acceleration in the x, y, and z directions (the horizontal directions x and y and the vertical direction z). The vibration displacement and velocity can be obtained by integrating the acceleration. In this embodiment, the velocity is mainly statistically analyzed.

[0031] This embodiment also includes a wireless receiving router, the ZBNET-300C-U. The ZBNET-300C-U is a Zigbee-to-Ethernet gateway device designed to industrial standards, enabling high-speed transparent transmission between Zigbee networks and Ethernet. This allows for rapid internet access to Zigbee local area networks without the need for secondary development, enabling remote Zigbee control and data collection. It also supports compatible communication with the ZM5168 series Zigbee modules. The device utilizes a high-power Zigbee RF transceiver, offering enhanced receiving sensitivity and a line-of-sight coverage radius of up to 2.5 km.

[0032] The vibration signal collector described in this example uses the ZXP6A, with dimensions of 237 × 180 × 60 mm and a weight of 2 kg. Each vibration channel can be connected to an acceleration sensor, and the host computer configuration determines the channel's input signal type. If a threaded hole is available at the test point, installation can be performed similarly to the velocity sensor installation diagram above. The vibration sensor can also be mounted using a dedicated magnetic base. Connect the vibration sensor to the base and attach the base to the test point during use.

[0033] Industrial Switching Power Supply (24V): The EDR-75-24 is a 75W DIN-rail power supply that complies with German industrial standards. The entire series uses a full range of AC input from 90Vac to 264Vac and complies with the EU-specified harmonic current regulations of EN61000-3-2.

[0034] Miniature circuit breaker: IC65N C10A / 2P circuit breaker complies with GB / T10963.1 and IEC / EN 60898-1 standards and has the following functions: short-circuit protection, overload protection, isolation function, clear indication of fault disconnection, and a red window on the front to indicate circuit breaker fault tripping; The data acquisition box is configured with data acquisition and display software: it provides functions such as vibration signal data acquisition, storage, feature calculation, and signal graphic display.

[0035] Main technical requirements for the equipment related to the device (1) Vibration sensor -Vibration measurement uses the piezoelectric principle and supports the industry standard IEPE.

[0036] -The sensor's standard range is not less than ±10g.

[0037] -The sensor frequency range should support 0.4Hz-5kHz (±3dB) to ensure that it can effectively pick up vibration signals from low frequency band to high frequency band -The sensor probe should be made of no less than 304 stainless steel to ensure stability in harsh environments.

[0038] -Output mode: X, Y, Z three-way L5, center through hole installation, 3-M5 connector output - Protection level: no less than IP66 -Operating temperature: +150℃ ~ +200℃ (2) Data collector -Support vibration signal collection - Sampling bit: no less than 16-bit ADC, external AD - Sampling frequency: not less than 50K / sps, configurable -Communication mode: 100M Ethernet -Operating temperature: -10℃ ~ +70℃ (3) Protective box -Outdoor installation, SUS304 material, with mounting base.

[0039] - Protection level: not less than IP55 (4) Data processing terminal -Desktop computer - CPU: no less than Intel i7 -Memory: no less than 16G -Monitor: no less than 27 inches -Solid state drive: no less than 2T -Operating system: Windows 10 / 11 Vibration acceleration sensor (three-axis) technical parameters: Sensitivity (20+5°C) 100mV / g Measuring range (peak): 50g Maximum lateral sensitivity ≤5% Frequency response (+5%) 1- 5000Hz Installation resonant frequency 15000Hz Operating temperature range -40~+120℃ Impact limit (peak): 2000g Maximum output signal (peak value) ≤6V Noise <2mg Output impedance <1000 Power supply (constant current source) +18~+30VDC Working current +2~+10mA DC bias voltage 7±1V Installing M5 Sensitive material piezoelectric ceramics Structural design ring shear Bright body material stainless steel Weight: 33g Accessories: M5 bolt, protective cap, one; 2m double-ended L5STYV-1, three Wireless vibration accelerometer technical parameters: Applicable scope: Vibration temperature monitoring of large rotating machinery, speed> 600rpm Vibration frequency range 2~10kHz Vibration measurement range (PP): Acceleration: ±10g, Speed: ±100mm / s Resonant frequency 38±3kHz Frequency response accuracy 2~5Hz: <10%, 5~10KHz: <3dB Linear accuracy 80Hz, <2% Vibration direction: single axis Temperature measurement range: -40 to 120 degrees Parameterization options: vibration (Veff / aPeak), switching output, switching logic, self-test, fault indication, filtering, etc. Switching output PNP or NPN mode selectable, parameterizable via IO-Link Working voltage: internal battery power supply, internal lithium-ion battery power supply Working hours Normal working status (transmission 1 time / hour): >180 days Installation method: (1) Threaded installation: 1 / 4-28 thread; (2) Magnetic base installation; (3) Glue attachment.

[0040] The software platform should have the following functions: Provide management functions for collection devices and sensors; Provide time domain and frequency domain display functions; Provides data saving and exporting functions.

[0041] Example 2: The difference from Example 1 is that in this embodiment, three vibration sensors are arranged in a circle at equal distances of 120 degrees in the same plane, and the vibration sensors are located on the outside of the trolley base or the upper edge of the ladle; in actual engineering applications, a special magnetic base can be used for installation, which can be installed during inspection and removed after inspection; threaded fixed installation can also be used, and the installation method and position must be considered to avoid the impact of splashing and dumping of molten steel.

[0042] Example 3: The difference from Example 1 is that in this embodiment, four vibration sensors are arranged equidistantly and 90 degrees apart in a circle in the same plane, and are installed at the bottom of the ladle, the side of the ladle, the upper edge of the ladle or on the trolley.

[0043] Example 4: This embodiment differs from Example 1 in that vibration sensors are symmetrically positioned in two or more different planes. Specifically, one vibration sensor is installed on each side of the ladle's two hanging ears, on the sides of the trolley support bases of the two hanging ears, and in directions parallel and perpendicular to the trolley base, for a total of eight vibration sensors. The ladle can be placed on the trolley (not shown) via the support bases or directly on the trolley base.

[0044] Example 5: A ladle refining monitoring method based on vibration measurement, based on the ladle refining monitoring device with symmetrically arranged vibration sensors, collects the vibration amount of the symmetrically installed vibration sensors within the window time (also called window time) 、 ..., extract the first eigenvalue corresponding to the vibration amount 、 …and the second eigenvalue 、 …,in, is the sampling sequence number. The sampling period is determined by the vibration frequency and the characteristics of the sensor and the data acquisition instrument (data acquisition box). The first subscript of the vibration quantity and characteristic value identifies the vibration sensor number. The monitoring method includes monitoring method 1 or monitoring method 2. The monitoring method includes: if all the , j≠k (e.g. ), the ladle is considered to be stirred evenly, otherwise it needs to be stirred further, where The first threshold is the first threshold. This means that if the vibration transfer characteristics of the symmetrical ladle positions are consistent and persist for a period of time (window duration), the molten steel in the ladle can be considered uniformly stirred. The first threshold is the allowable difference in the characteristic value of the vibration in the symmetrical direction under the uniform stirring state. The smaller the threshold, the more uniform the stirring, but the higher the stirring time and gas stirring flow rate control requirements.

[0045] The second monitoring method includes: if all the , j≠k (e.g. ), and satisfy all (like and etc.), the ladle is considered to be stirred evenly, otherwise it needs to be stirred further, among which, The second threshold is used. This means that in addition to determining the difference between the first characteristics of symmetrically mounted vibration sensors, Monitoring Method 2 also determines whether the second characteristic value of each vibration sensor is within a certain range. For example, the second characteristic value is the variance of the respective vibration quantities within the window duration. When the variance is sufficiently small, it indicates that the stirred molten steel has locally entered a steady state. Furthermore, if the vibration characteristics of different local areas are essentially consistent, it can be determined that the stirring is uniform, which is reasonable. Monitoring Method 2 is essentially an analytical and judgment method that meets higher quality requirements for steelmaking products. Note that the characteristic values ​​of vibration quantities in different directions should be counted separately and cannot be mixed.

[0046] Preferably, the first eigenvalue includes at least one of the mean, median, and norm. In this embodiment, the mean value of the vibration amount within the window duration is taken as the basic information for analysis and judgment; the second eigenvalue includes at least one of the variance (RMS, root mean square value), standard deviation, maximum value, minimum value, and extreme value difference. The extreme value difference is the difference between the maximum value and the minimum value. In this embodiment, the second eigenvalue takes the variance of the vibration amount.

[0047] Preferably, the lower limit of the window duration is not less than 3 longest vibration cycle durations, and the upper limit is not greater than the minimum lag duration.

[0048] The lower limit of the window duration is set mainly to facilitate statistical calculation of vibration quantity. At least three complete vibration cycles should be sampled and at least three groups of valid amplitude values ​​should be obtained. Only in this way can the amplitude statistical calculation be meaningful. In fact, it should generally be more than 10 or even 20 valid vibration cycles to basically guarantee the accuracy and reliability of the statistical calculation. That is, the vibration quantity sampling coverage time corresponding to the calculated characteristic value should be long enough (not less than the lower limit time) to ensure the accuracy of the stirring characteristic judgment. The shorter the window duration, the higher the real-time performance.

[0049] The upper limit of the window duration is primarily determined by the consideration that it cannot be too long. Otherwise, the time-varying characteristics of the stirring effect will be averaged over time, making it difficult to determine whether the stirring effect has truly met the target, resulting in inaccurate or even meaningless conclusions. Furthermore, if the window duration is too long, the statistical results will not reflect the actual situation in real time, reducing real-time performance, which in turn reduces the efficiency of monitoring and judgment, and hinders subsequent real-time control. Third, the longer the window duration, the greater the computational workload. Fourth, the maximum lag duration is used as a reference for the upper limit of the window duration. This is mainly due to the consideration that if the molten steel is in the lag phase transition (a clearly non-steady-state phase), the statistical characteristics should show a clear response. If the window duration exceeds this duration, the excessive steady-state data introduced will be detrimental to the statistical characteristic judgment, i.e., anomalies may be averaged out. The lag duration, including changes in the stirring gas flow rate or velocity, or the addition of additives, generally requires a certain lag time before the molten steel reaches a relatively steady state.

[0050] In this embodiment, the window time length is set to 10s, mainly considering that a too long window time length will affect the timeliness of the stirring effect judgment. Although it is shorter than the vibration effect lag time, considering that the vibration amount changes dramatically during this lag process, the characteristic value is almost impossible to meet the requirements of the monitoring method 1 and the monitoring method 2, so it is feasible to appropriately shorten the time and improve the efficiency.

[0051] Accuracy and timeliness are sometimes conflicting requirements for window duration and require a compromise.

[0052] Preferably, the monitoring method includes a sliding window monitoring method, that is, the window slides once per unit time, and the vibration amount and its characteristic value within the sliding window duration are analyzed and judged according to the monitoring method one or the monitoring method two; the unit time includes an integer second (such as every 1 second or every 2 seconds, etc.) or a unit time greater than or equal to the longest vibration period or greater than or equal to an integer multiple of the sampling period. The use of integer second intervals for the window sliding time interval is consistent with traditional sampling cognition habits; while the use of intervals greater than the longest vibration period considers sliding once for at least one complete vibration period, and in fact, it generally slides once for multiple such vibration periods; the use of integer multiples of the sampling period facilitates data statistics and calculations, and different options have different advantages. This embodiment has a sampling rate of 10kHz and adopts a 1s sliding time interval, while meeting the requirement of being greater than the longest vibration period (for vibration signals with a minimum period of 2Hz and 0.5s). Therefore, this setting essentially meets the above three conditions at the same time.

[0053] The present invention realizes effective on-line monitoring of gas stirring intensity by introducing equipment such as a vibration acceleration sensor, a signal acquisition unit, and an industrial control unit.

[0054] Example 6: The difference from Example 5 is that the window length in this embodiment is 21 seconds. This is mainly because according to the analysis of actual experimental data, when performing central median smoothing filtering, a window length of 21 seconds is selected, and the correlation between gas flow rate and vibration characteristics is the strongest, which can obtain the best vibration characteristics of gas stirring.

[0055] The basic principle of the present invention is as follows: when the ladle is not stirred uniformly, the stirring vibration effect on the symmetrically installed vibration sensors will inevitably lead to differences in the measurement data characteristics due to differences in the transmission paths. Therefore, the monitoring device, monitoring method and real-time air blowing control method can all be designed based on this basic principle.

[0056] Regarding the acquisition of empirical parameters such as thresholds in the monitoring method, since the gas stirring effect is judged by difference, there is no need to consider too much consistency of environmental parameters. It is only necessary to conduct real-time monitoring of the ladle that is actually stirred under the traditional empirical stirring intensity and time, and extract the characteristic value difference of the corresponding grade according to the quality of the final product. This can be used as a threshold reference for products of different grades (performance grades) when the present invention is applied. In special cases, different thresholds can also be set for different product models (including differences in additive types, addition amounts and process sequences), different ladle sizes, different trolley environments, and different blowing methods. In any case, the comparison of differences can filter out the influence of various common factors, while the use of absolute values ​​of vibration measurements, ladle response values ​​(LRV) or rolling ladle response values ​​(rLRV) will be affected by dynamic factors, and the differences may be large. There is almost no reference between each other, and it is difficult to analyze and separate effective values. The difficulty of obtaining accurate empirical parameters is much higher than that of the present invention. Furthermore, the difference thresholds for the characteristic values ​​of the empirical parameter vibration quantity of the present invention vary slightly across different environments and ladles (this threshold requirement differs only for steel products of different models and qualities. Obviously, the smaller the threshold, the better the product performance, the higher the stirring time or airflow intensity requirements, and of course, the higher the sensor measurement accuracy requirements). These values ​​are highly relatable because many uncertain influencing factors are eliminated during the subtraction process, leaving only the effects of uneven stirring. Furthermore, due to the use of highly sensitive sensors and high-precision sampling of no less than 16 bits, differences in vibration quantity caused by uneven stirring can be identified when subtracting symmetrically mounted sensors, making the present method even more practical.

[0057] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the technical principles of the present invention, they can also make several improvements and modifications, such as the specific layout of the vibration sensor, the composition of the data acquisition and analysis system, etc. Without departing from the utilization of symmetry characteristics, these improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A ladle refining monitoring device based on vibration measurement, characterized in that: The monitoring device includes at least two vibration sensors that are symmetrical in distance and angle and are in the same installation plane, and a signal acquisition and analysis module electrically connected to the vibration sensor, and an information warning display module is electrically connected to the signal acquisition and analysis module; the fixed installation position of the vibration sensor includes the bottom of the ladle, the outside of the ladle, the ladle hanging ear, the upper edge of the ladle, or a trolley fixed to the ladle; the symmetrical installation includes the central axis of the ladle as the symmetry axis, and the electrical connection includes a wired connection and / or a wireless connection; The vibration sensor measures the vibration amount in at least one of the three directions of x, y, and z, and the vibration amount includes at least one of displacement, velocity, or acceleration.

2. The ladle refining monitoring device based on vibration measurement according to claim 1, characterized in that: The installation position of the vibration sensor on the trolley includes a support seat, or a support platform base or a support platform column, and the installation position transmits the vibration caused by the stirring of the molten steel inside the ladle.

3. The ladle refining monitoring device based on vibration measurement according to claim 1, characterized in that: Three vibration sensors are arranged in a circle at equal distances of 120 degrees in the same plane.

4. The ladle refining monitoring device based on vibration measurement according to claim 1, characterized in that: Four vibration sensors are arranged in a circle at equal distances of 90 degrees in the same plane.

5. The ladle refining monitoring device based on vibration measurement according to claim 1, characterized in that: Vibration sensors are symmetrically arranged in two or more different planes.

6. The ladle refining monitoring device based on vibration measurement according to claim 1, characterized in that: The vibration sensor comprises a wireless vibration sensor, which is connected to the signal acquisition and analysis module by radio, and the wireless connection is realized through a wireless routing relay unit.

7. The ladle refining monitoring device based on vibration measurement according to claim 1, characterized in that: The signal acquisition and analysis module includes an integrated data acquisition box, which includes a vibration collector, an industrial switching power supply and a circuit breaker.

8. A ladle refining monitoring method based on vibration measurement, characterized in that: The vibration amount of the symmetrically installed vibration sensors within the acquisition window 、 ..., extract the first eigenvalue corresponding to the vibration amount 、 …and the second eigenvalue 、 …,in, is a sampling sequence number, and the monitoring method includes monitoring method 1 or monitoring method 2; The monitoring method includes: if all the , j≠k, the ladle is considered to be stirred evenly, otherwise it needs to be stirred further, where is the first threshold; The second monitoring method includes: if all the , j≠k, and satisfy all , the ladle is considered to be stirred evenly, otherwise it needs to be stirred further, among which, is the second threshold; The first eigenvalue describes the magnitude of the vibration amount, and the second eigenvalue describes the degree of discreteness of the vibration sequence.

9. The ladle refining monitoring method based on vibration measurement according to claim 8, characterized in that: The first eigenvalue includes at least one of mean, median, and norm; the second eigenvalue includes at least one of variance, standard deviation, maximum value, minimum value, and extreme value difference.

10. The ladle refining monitoring method based on vibration measurement according to claim 8, characterized in that: The lower limit of the window duration is not less than 3 longest vibration cycles, and the upper limit is not greater than the minimum lag duration.

11. The ladle refining monitoring method based on vibration measurement according to claim 8, characterized in that: The monitoring method includes a sliding window monitoring method, that is, the unit time window slides once, and the vibration amount and its characteristic value within the sliding window time are analyzed and judged according to the monitoring method one or the monitoring method two; the unit time includes an integer second or a unit time greater than or equal to the longest vibration period or greater than or equal to an integer multiple of the sampling period.

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