Corrosion grade measurement accuracy evaluation method and device

Abstract

The invention discloses a corrosion grade measurement accuracy evaluation method and device, the method is used for evaluating the corrosion grade measurement accuracy of a corrosion sensor, and the method comprises the following steps: using a metered microscope to measure the initial thickness value of a carbon steel test piece; based on a preset corrosion time set, measuring by using a metered microscope to obtain a thickness sequence value of the carbon steel test piece under the corrosion time set; based on a preset corrosion time set, measuring by using a corrosion sensor to obtain a resistance ratio sequence of the carbon steel test piece under the corrosion time set; and performing accuracy rate evaluation processing on the initial thickness value, the thickness sequence value and the resistance ratio sequence to obtain a grade measurement accuracy rate evaluation result value of the corrosion sensor.

Description

Technical Field

[0001] The invention relates to the field of corrosion measurement, and in particular to a method and device for evaluating the accuracy of corrosion level measurement. Background Art

[0002] The corrosion damage of metal materials in the atmosphere is mainly caused by the alternation of dry and wet climates. Corrosion monitoring technology is to more intuitively understand the corrosion process, study the corrosion mechanism, and thus control the corrosion process and minimize the corrosion damage. By measuring and classifying the corrosion of metal materials, it is possible to more effectively classify and grade the corrosion prevention management of metal materials, thereby extending the service life of metal materials.

[0003] How to quickly and accurately evaluate the accuracy of current devices and methods that can measure and classify the corrosion level of metal materials is an issue that urgently needs to be addressed. Summary of the invention

[0004] The present invention mainly solves the problem of how to quickly and accurately evaluate the accuracy of the current measurement and classification method for metal material corrosion levels. The present invention discloses a corrosion level measurement accuracy evaluation method and device.

[0005] In a first aspect of an embodiment of the present application, a method for evaluating the accuracy of corrosion level measurement is disclosed, which is used to evaluate the accuracy of corrosion level measurement of a corrosion sensor, comprising:

[0006] S1, using a measured microscope, measure the initial thickness of the carbon steel specimen;

[0007] S2, based on a preset corrosion time set, using a measured microscope, measuring the thickness sequence value of the carbon steel test piece under the corrosion time set;

[0008] S3, based on a preset corrosion time set, using a corrosion sensor, measuring a resistance ratio sequence of the carbon steel test piece under the corrosion time set;

[0009] S4, performing accuracy evaluation processing on the initial thickness value, thickness sequence value and resistance ratio sequence to obtain a grade measurement accuracy evaluation result value of the corrosion sensor.

[0010] The corrosion sensor is used to measure the resistance ratio of the test piece to be measured, and process the resistance ratio using a preset corrosion grade classification model to obtain the corrosion grade value of the test piece to be measured;

[0011] The corrosion grade classification model includes a plurality of corrosion grade information and corresponding value intervals;

[0012] The resistance ratio is processed using a preset corrosion grade classification model to obtain the corrosion grade value of the test piece to be measured, which is to confirm that the corrosion grade information corresponding to the value interval to which the resistance ratio belongs is the corrosion grade value of the test piece to be measured.

[0013] The corrosion sensor measures the resistance ratio of the test piece to be measured by dividing the resistance value of the test piece to be measured by the resistance value of the flat-plate resistance probe sensitive element of the corrosion sensor; the size of the flat-plate resistance probe sensitive element is the same as the size of the test piece to be measured.

[0014] The accuracy evaluation process is performed on the initial thickness value, the thickness sequence value and the resistance ratio sequence to obtain the grade measurement accuracy evaluation result value of the corrosion sensor, including:

[0015] S41, using each element of the thickness sequence value to divide by the initial thickness value, respectively, to obtain a standard resistance ratio sequence;

[0016] S42, performing data cleaning processing on the resistance ratio sequence to obtain a measured resistance ratio sequence;

[0017] S43, performing accuracy evaluation processing on the standard resistance ratio sequence and the measured resistance ratio sequence to obtain a grade measurement accuracy evaluation result value of the corrosion sensor.

[0018] The accuracy evaluation process is performed on the standard resistance ratio sequence and the measured resistance ratio sequence to obtain the grade measurement accuracy evaluation result value of the corrosion sensor, including:

[0019] S431, subtracting the standard resistance ratio sequence from the measured resistance ratio sequence to obtain a difference sequence;

[0020] S432, performing a first accuracy evaluation process on the difference sequence to obtain a first accuracy evaluation value;

[0021] S433, using a preset corrosion grade classification model to process the measured resistance ratio sequence to obtain a corrosion grade sequence; the elements of the corrosion grade sequence are the corrosion grade values ​​corresponding to each element of the measured resistance ratio sequence;

[0022] S434, performing a second accuracy evaluation process on the difference sequence and the corrosion level sequence to obtain a second accuracy evaluation value;

[0023] S435, performing weight calculation processing on the difference sequence and the corrosion level sequence to obtain a first weight value and a second weight value;

[0024] S436: Using the first weight value and the second weight value, perform weighted sum processing on the first accuracy evaluation value and the second accuracy evaluation value to obtain a grade measurement accuracy evaluation result value of the corrosion sensor.

[0025] The expression of the first accurate evaluation process is:

[0026]

[0027] Among them, α is the first accuracy evaluation value, a i 、b i 、c i are the i-th item of the difference sequence, the standard resistance ratio sequence and the measured resistance ratio sequence respectively, N is the length value of the standard resistance ratio sequence, and ω is the preset weight value;

[0028] The expression of the second accurate evaluation process is:

[0029]

[0030] Among them, β is the second accuracy evaluation value, m i is the midpoint value of the corrosion grade value interval corresponding to the i-th element of the measured resistance ratio sequence, A i and B i are respectively the upper and lower bounds of the value interval of the corrosion grade value corresponding to the ith element of the measured resistance ratio sequence, and exp() represents the power function of the constant e.

[0031] The weight calculation process is performed on the difference sequence and the corrosion level sequence to obtain a first weight value and a second weight value, including:

[0032] Calculate the variance and mean of the difference sequence, and use the quotient of the mean and the variance as the first weighted value;

[0033] The median value and the mean value of the corrosion grade sequence are calculated, and the quotient of the median value and the mean value is used as the second weighted value.

[0034] In a second aspect of an embodiment of the present invention, a device for evaluating the accuracy of corrosion level measurement is disclosed, the device comprising:

[0035] A memory storing executable program code;

[0036] a processor coupled to the memory;

[0037] The processor calls the executable program code stored in the memory to execute the corrosion level measurement accuracy assessment method.

[0038] According to a third aspect of an embodiment of the present invention, a computer storable medium is disclosed, wherein the computer storable medium stores computer instructions, and when the computer instructions are called by a computer, they are used to execute the accuracy assessment method for corrosion level measurement.

[0039] According to a fourth aspect of an embodiment of the present invention, an information data processing terminal is disclosed. The information data processing terminal is used to implement the accuracy assessment method of corrosion level measurement.

[0040] The beneficial effects of the present invention are:

[0041] The invention discloses a method and device for evaluating the accuracy of corrosion grade measurement, which realizes a rapid and accurate evaluation of the accuracy of the current metal material corrosion grade measurement and classification method.

[0042] The present invention uses a metered microscope to accurately measure the initial thickness value of a carbon steel test piece; based on a preset corrosion time set, the metered microscope is used to measure the thickness sequence value of the carbon steel test piece under the corrosion time set; based on the preset corrosion time set, a corrosion sensor is used to measure the resistance ratio sequence of the carbon steel test piece under the corrosion time set; the initial thickness value, thickness sequence value and resistance ratio sequence are evaluated for accuracy to obtain a grade measurement accuracy evaluation result value of the corrosion sensor, and by accumulating long-term measurement values, an accurate and comprehensive evaluation of the measurement classification of the metal material corrosion grade is achieved.

[0043] In the process of evaluating the accuracy of grade measurement, the standard resistance ratio sequence and the measured resistance ratio sequence are subtracted to obtain a difference sequence; a first accurate evaluation processing model and a second accurate evaluation processing model are established respectively, so as to realize the extraction of difference features of different types of data and realize accurate evaluation.

[0044] In the evaluation of grade measurement accuracy, the present invention not only considers the difference between the standard resistance ratio sequence and the measured value, but also evaluates the numerical value of each interval of the corrosion grade classification model, thereby ensuring the comprehensiveness of the evaluation result. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a flow chart for implementing the method of the present invention. DETAILED DESCRIPTION

[0046] In order to better understand the content of the present invention, an embodiment is given here.

[0047] Figure 1 It is a flow chart for implementing the method of the present invention.

[0048] The present invention mainly solves the problem of how to quickly and accurately evaluate the accuracy of the current measurement and classification method for metal material corrosion levels. The present invention discloses a corrosion level measurement accuracy evaluation method and device.

[0049] In a first aspect of an embodiment of the present application, a method for evaluating the accuracy of corrosion level measurement is disclosed, which is used to evaluate the accuracy of corrosion level measurement of a corrosion sensor, comprising:

[0050] S1, using a measured microscope, measure the initial thickness of the carbon steel specimen;

[0051] S2, based on a preset corrosion time set, using a measured microscope, measuring the thickness sequence value of the carbon steel test piece under the corrosion time set;

[0052] S3, based on a preset corrosion time set, using a corrosion sensor, measuring a resistance ratio sequence of the carbon steel test piece under the corrosion time set;

[0053] S4, performing accuracy evaluation processing on the initial thickness value, thickness sequence value and resistance ratio sequence to obtain a grade measurement accuracy evaluation result value of the corrosion sensor;

[0054] The corrosion sensor is used to measure the resistance ratio of the test piece to be measured, and process the resistance ratio using a preset corrosion grade classification model to obtain the corrosion grade value of the test piece to be measured.

[0055] The corrosion grade classification model includes a plurality of corrosion grade information and corresponding value intervals;

[0056] The resistance ratio is processed using a preset corrosion grade classification model to obtain the corrosion grade value of the test piece to be measured, which is to confirm that the corrosion grade information corresponding to the value interval to which the resistance ratio belongs is the corrosion grade value of the test piece to be measured.

[0057] The corrosion sensor measures the resistance ratio of the test piece to be measured by dividing the resistance value of the test piece to be measured by the resistance value of the flat-plate resistance probe sensitive element of the corrosion sensor; the size of the flat-plate resistance probe sensitive element is the same as the size of the test piece to be measured;

[0058] The accuracy evaluation process is performed on the initial thickness value, the thickness sequence value and the resistance ratio sequence to obtain the grade measurement accuracy evaluation result value of the corrosion sensor, including:

[0059] S41, using each element of the thickness sequence value to divide by the initial thickness value, respectively, to obtain a standard resistance ratio sequence;

[0060] S42, performing data cleaning processing on the resistance ratio sequence to obtain a measured resistance ratio sequence;

[0061] S43, performing accuracy evaluation processing on the standard resistance ratio sequence and the measured resistance ratio sequence to obtain a grade measurement accuracy evaluation result value of the corrosion sensor;

[0062] The accuracy evaluation process is performed on the standard resistance ratio sequence and the measured resistance ratio sequence to obtain the grade measurement accuracy evaluation result value of the corrosion sensor, including:

[0063] Subtracting the standard resistance ratio sequence from the measured resistance ratio sequence to obtain a difference sequence;

[0064] Performing a first accuracy evaluation process on the difference sequence to obtain a first accuracy evaluation value;

[0065] The measured resistance ratio sequence is processed using a preset corrosion grade classification model to obtain a corrosion grade sequence; the elements of the corrosion grade sequence are the corrosion grade values ​​corresponding to each element of the measured resistance ratio sequence;

[0066] Performing a second accuracy evaluation process on the difference sequence and the corrosion level sequence to obtain a second accuracy evaluation value;

[0067] Performing weight calculation processing on the difference sequence and the corrosion grade sequence to obtain a first weight value and a second weight value;

[0068] Using the first weight value and the second weight value, weighted summing the first accuracy evaluation value and the second accuracy evaluation value is performed to obtain a grade measurement accuracy evaluation result value of the corrosion sensor;

[0069] The expression of the first accurate evaluation process is:

[0070]

[0071] Among them, α is the first accuracy evaluation value, a i , b i 、c i are the i-th item of the difference sequence, the standard resistance ratio sequence and the measured resistance ratio sequence respectively, N is the length value of the standard resistance ratio sequence, and ω is a preset weight value, which can be 0.2.

[0072] The expression of the second accurate evaluation process is:

[0073]

[0074] Among them, β is the second accuracy evaluation value, m iis the midpoint value of the corrosion grade value interval corresponding to the i-th element of the measured resistance ratio sequence, A i and B i are the upper and lower bounds of the corrosion level value interval corresponding to the ith element of the measured resistance ratio sequence, respectively, and exp() represents the power function of the constant e. The corrosion level value has the same meaning as the corrosion level information.

[0075] The weight calculation process is performed on the difference sequence and the corrosion level sequence to obtain a first weight value and a second weight value, including:

[0076] Calculate the variance and mean of the difference sequence, and use the quotient of the mean and the variance as the first weighted value;

[0077] Calculate the median value and the mean value of the corrosion grade sequence, and use the quotient of the median value and the mean value as the second weighted value;

[0078] The weight calculation process is performed on the difference sequence and the corrosion level sequence to obtain a first weight value and a second weight value, including:

[0079]

[0080] Wherein, τ is the variance value of the difference sequence, φ is the mean value of the difference sequence, ρ is the median value of the difference sequence, H1 and H2 are the first weight value and the second weight value respectively, and μ and ν are the variance and mean value of the corrosion grade sequence respectively;

[0081] The data cleaning process includes filling missing values, smoothing noise data, and smoothing or deleting outliers; the smoothed noise data is obtained by first determining the noise data, and then smoothing the noise data according to the data before and after the noise data; the noise data is a value whose value is less than the detection sensitivity of the sensor of the observed data, or greater than the measurement upper limit of the sensor of the observed data. The outlier point can be determined by the Kalman filter method. The filling value of the missing value can be determined by averaging the measured values ​​within a certain sampling interval before and after the missing value.

[0082] The corrosion time set may be half a year, 1 year, 2 years, 3 years or 5 years, or a corrosion time set consisting of a 5-year period with each month as a time point.

[0083] In the present invention, the test piece to be measured is a carbon steel test piece.

[0084] In a second aspect of an embodiment of the present invention, a device for evaluating the accuracy of corrosion level measurement is disclosed, the device comprising:

[0085] A memory storing executable program code;

[0086] a processor coupled to the memory;

[0087] The processor calls the executable program code stored in the memory to execute the corrosion level measurement accuracy assessment method.

[0088] According to a third aspect of an embodiment of the present invention, a computer storable medium is disclosed, wherein the computer storable medium stores computer instructions, and when the computer instructions are called by a computer, they are used to execute the accuracy assessment method for corrosion level measurement.

[0089] According to a fourth aspect of an embodiment of the present invention, an information data processing terminal is disclosed. The information data processing terminal is used to implement the accuracy assessment method of corrosion level measurement.

[0090] In a fifth aspect of an embodiment of the present invention, a method for evaluating the accuracy of corrosion grade measurement is disclosed. In this method, an integrated corrosion sensor and a carbon steel weightlessness hanging plate are placed in the same storage environment. After being placed for a period of time (for example, 6 months), the average corrosion rates measured by the weightlessness hanging plate and the integrated corrosion sensor are compared, and the weightlessness hanging plate value and the sensor measurement value are recorded in Table 1 at the same time. If the atmospheric weightlessness hanging plate test result is graded at C2, and the corrosion rate measured by the integrated corrosion sensor is between 1.3μm / a and 25μm / a, the two measurement methods are considered to have the same grade, and the early warning accuracy is 100%.

[0091] Table 1 Carbon steel atmospheric corrosion rate classification measurement data record

[0092]

[0093] If 98 out of 100 corrosion rate classifications measured by the weightlessness coupon and the corrosion sensor are in the same partition C1-C5 or CX, it can be considered that the requirement of 98% early warning accuracy is met.

[0094] In view of the fact that the corrosion time of carbon steel weight loss coupons is relatively long and the test results cannot be obtained in a short period of time, the following method is used to verify the early warning accuracy of the instrument:

[0095] In order to verify the accuracy of the instrument in measuring corrosion levels, carbon steel test pieces of different thicknesses were used to simulate the metal corrosion thinning state, and the resistance ratio of the carbon steel test pieces was measured by the equipment to determine the corresponding corrosion level (C1~C5).

[0096] Under the condition of corrosion time of 5 years, the resistance ratio range corresponding to the corrosion level (C1~C5) is calculated by the original thickness of the carbon steel test piece as the standard basis.

[0097] The resistance ratio of the carbon steel test piece is measured using a corrosion sensor, and then compared with the resistance ratio range corresponding to the corrosion grade (C1~C5) under the above 5-year corrosion time condition. If the resistance ratio measured by the corrosion sensor for 5 consecutive times is within the corresponding resistance ratio classification value range of C1~C5, the instrument is deemed qualified.

[0098] Accuracy measurement method:

[0099] ① Use a measured microscope to measure the initial thickness of the carbon steel specimen.

[0100] ② Calculate the corresponding resistance ratio range based on the initial thickness of the carbon steel test piece and the corrosion grade (C1~C5).

[0101] ③ Make 2 kinds of thickness at random and verify 2 corrosion levels among C1-C5.

[0102] ④ Use the integrated corrosion sensor to measure the resistance ratio of carbon steel specimens of two thicknesses, and compare whether the measured value is consistent with the resistance ratio range of the corrosion grade (C1~C5). For details, see Table 2.

[0103] Table 2 Data record table

[0104]

[0105] The method of calculating the resistance ratio by corrosion rate: Assuming the initial thickness of the metal sheet is m, the corrosion rate is c, and the corrosion time is t. The thickness value of corrosion in t years: y = c × t.

[0106] Resistance ratio r = initial thickness / uncorroded thickness = m / (my).

[0107] Corrosion rate calculation method:

[0108] For the flat-plate resistance probe sensitive element, the corrosion rate calculation formula is as follows, the resistance ratio of the probe is λ:

[0109]

[0110] λ=R x / R f =L x *w f *d f / L f *w x *d x

[0111] Where L x 、w x ,d x are the length, width and thickness of the exposed plate (corrosion sheet), and L f 、w f,d f is the length, width and thickness of the built-in plate (the protected reference plate), considering that the width of the inner and outer plates is the same, that is, w x =w f , and will not change during the entire measurement process. At the same time, the length of the inner and outer plates will not change over time, so:

[0112]

[0113] Then the remaining thickness of the metal sheet at time t is:

[0114]

[0115] The corrosion rate at time t is:

[0116]

[0117] Where CR is the corrosion rate, d t and λ t Represent the remaining thickness and resistance ratio at time t respectively.

[0118] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A method for evaluating the accuracy of corrosion level measurement, characterized in that: Used to evaluate the accuracy of corrosion level measurement of corrosion sensors, including: S1, using a measured microscope, measure the initial thickness of the carbon steel specimen; S2, based on a preset corrosion time set, using a measured microscope, measuring the thickness sequence value of the carbon steel test piece under the corrosion time set; S3, based on a preset corrosion time set, using a corrosion sensor, measuring a resistance ratio sequence of the carbon steel test piece under the corrosion time set; S4, performing accuracy evaluation processing on the initial thickness value, thickness sequence value and resistance ratio sequence to obtain a grade measurement accuracy evaluation result value of the corrosion sensor.

2. The method for evaluating the accuracy of corrosion level measurement according to claim 1, characterized in that: The corrosion sensor is used to measure the resistance ratio of the test piece to be measured, and process the resistance ratio using a preset corrosion grade classification model to obtain the corrosion grade value of the test piece to be measured; The corrosion grade classification model includes a plurality of corrosion grade information and corresponding value intervals; The resistance ratio is processed using a preset corrosion grade classification model to obtain the corrosion grade value of the test piece to be measured, which is to confirm that the corrosion grade information corresponding to the value interval to which the resistance ratio belongs is the corrosion grade value of the test piece to be measured.

3. The method for evaluating the accuracy of corrosion level measurement according to claim 2, characterized in that: The corrosion sensor measures the resistance ratio of the test piece to be measured by dividing the resistance value of the test piece to be measured by the resistance value of the flat-plate resistance probe sensitive element of the corrosion sensor; the size of the flat-plate resistance probe sensitive element is the same as the size of the test piece to be measured.

4. The method for evaluating the accuracy of corrosion level measurement according to claim 2, characterized in that: The accuracy evaluation process is performed on the initial thickness value, the thickness sequence value and the resistance ratio sequence to obtain the grade measurement accuracy evaluation result value of the corrosion sensor, including: S41, using each element of the thickness sequence value to divide by the initial thickness value, respectively, to obtain a standard resistance ratio sequence; S42, performing data cleaning processing on the resistance ratio sequence to obtain a measured resistance ratio sequence; S43, performing accuracy evaluation processing on the standard resistance ratio sequence and the measured resistance ratio sequence to obtain a grade measurement accuracy evaluation result value of the corrosion sensor.

5. The method for evaluating the accuracy of corrosion level measurement according to claim 4, characterized in that: The accuracy evaluation process is performed on the standard resistance ratio sequence and the measured resistance ratio sequence to obtain the grade measurement accuracy evaluation result value of the corrosion sensor, including: S431, subtracting the standard resistance ratio sequence from the measured resistance ratio sequence to obtain a difference sequence; S432, performing a first accuracy evaluation process on the difference sequence to obtain a first accuracy evaluation value; S433, using a preset corrosion grade classification model to process the measured resistance ratio sequence to obtain a corrosion grade sequence; the elements of the corrosion grade sequence are the corrosion grade values ​​corresponding to each element of the measured resistance ratio sequence; S434, performing a second accuracy evaluation process on the difference sequence and the corrosion level sequence to obtain a second accuracy evaluation value; S435, performing weight calculation processing on the difference sequence and the corrosion level sequence to obtain a first weight value and a second weight value; S436: Using the first weight value and the second weight value, perform weighted sum processing on the first accuracy evaluation value and the second accuracy evaluation value to obtain a grade measurement accuracy evaluation result value of the corrosion sensor.

6. The method for evaluating the accuracy of corrosion level measurement according to claim 5, characterized in that: The expression of the first accurate evaluation process is: Among them, α is the first accuracy evaluation value, a i 、b i 、c i are the i-th item of the difference sequence, the standard resistance ratio sequence and the measured resistance ratio sequence respectively, N is the length value of the standard resistance ratio sequence, and ω is the preset weight value; The expression of the second accurate evaluation process is: Among them, β is the second accuracy evaluation value, m i is the midpoint value of the corrosion grade value interval corresponding to the i-th element of the measured resistance ratio sequence, A i and B i are respectively the upper and lower bounds of the value interval of the corrosion grade value corresponding to the ith element of the measured resistance ratio sequence, and exp() represents the power function of the constant e.

7. The method for evaluating the accuracy of corrosion level measurement according to claim 5, characterized in that: The weight calculation process is performed on the difference sequence and the corrosion level sequence to obtain a first weight value and a second weight value, including: Calculate the variance and mean of the difference sequence, and use the quotient of the mean and the variance as the first weighted value; The median value and the mean value of the corrosion grade sequence are calculated, and the quotient of the median value and the mean value is used as the second weighted value.

8. A device for evaluating the accuracy of corrosion level measurement, characterized in that: The device comprises: A memory storing executable program code; a processor coupled to the memory; The processor calls the executable program code stored in the memory to execute the corrosion level measurement accuracy assessment method according to any one of claims 1 to 7.

9. A computer storable medium, characterized in that: The computer storable medium stores computer instructions, and when the computer instructions are called by a computer, they are used to execute the accuracy assessment method for corrosion level measurement according to any one of claims 1 to 7.

10. An information data processing terminal, characterized in that: The information data processing terminal is used to implement the accuracy assessment method for corrosion level measurement according to any one of claims 1 to 7.

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