A magnetostrictive waveguide detection data temperature compensation method

Abstract

The application belongs to the technical field of pipeline nondestructive testing, and particularly relates to a magnetostrictive guided wave detection data temperature compensation method. The magnetostrictive guided wave detection data temperature compensation method can be used for compensating the influence of temperature on magnetostrictive guided wave detection data, thereby avoiding errors in defect positioning and quantitative analysis, and ensuring the accuracy of magnetostrictive guided wave detection. The magnetostrictive guided wave detection data temperature compensation method comprises the steps of collecting magnetostrictive guided wave detection data, performing temperature compensation on the guided wave detection data, performing elimination processing on the detection data after temperature compensation at different time instants of the same pipeline, establishing a corresponding database of defect amplitude and defect loss amount, establishing a corresponding relationship between defect loss amount and echo amplitude data, and generating a defect evaluation database.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of pipeline nondestructive testing, and particularly relates to a magnetostrictive guided wave detection data temperature compensation method. BACKGROUND

[0002] The magnetostrictive guided wave detection technology is widely applied in the pipeline defect detection field due to its high detection efficiency, long test distance, no need of coupling agent, no need of stripping the anticorrosive layer and many other characteristics. However, the inventors find that the magnetostrictive ultrasonic guided wave detection data is prone to deviation in actual detection application occasions, for example, the magnetostrictive ultrasonic guided wave detection data is affected by the temperature of the detection object and fluctuates, thereby causing errors in defect positioning and quantitative analysis. SUMMARY

[0003] The application provides a magnetostrictive guided wave detection data temperature compensation method, which can be used for compensating the influence of temperature on the magnetostrictive guided wave detection data, thereby avoiding errors in defect positioning and quantitative analysis and ensuring the accuracy of the magnetostrictive guided wave detection.

[0004] To solve the above technical problems, the application adopts the following technical solutions:

[0005] A magnetostrictive guided wave detection data temperature compensation method comprises the following steps:

[0006] Step 1: collecting magnetostrictive guided wave detection data to obtain echo reflection time t and amplitude P under actual temperature T, and calculating defect distance L according to empirical wave speed v;

[0007] The empirical wave speed v is the wave speed measured by multiple tests under reference temperature T0;

[0008] Step 2: temperature compensating the empirical wave speed v to obtain actual wave speed v under actual temperature T T , and correcting the defect distance L according to the actual wave speed v T to obtain actual defect distance L T under actual temperature T.

[0009] Further, the following steps are further included:

[0010] Step 3: eliminating the detection data compensated at different times for the same pipeline to obtain the change of defect amplitude at different times for the same pipeline.

[0011] Further, the following steps are further included:

[0012] Step four: establishing the corresponding database of defect amplitude and defect loss amount, and establishing the corresponding relationship between defect loss amount and echo amplitude data, and generating defect evaluation database.

[0013] More preferably, the temperature compensation process of the empirical wave speed v in step two can be specifically described as:

[0014] The temperature compensation formula satisfies: v T =v-b (T0-T) ; wherein, v T is the actual wave speed under the actual temperature T, v is the empirical wave speed, b is the compensation coefficient, and T0 is the reference temperature.

[0015] Optionally, the reference temperature T0 is 20 DEG C, and the empirical wave speed v is 3248 m / s.

[0016] More preferably, the elimination process of the detection data of the same pipeline at different time after temperature compensation in step three can be specifically described as:

[0017] Taking distance as the x-axis and amplitude as the y-axis, the 0 value of the y-axis as the reference line,

[0018] The change of the defect amplitude of the same pipeline at different time satisfies: P0=y t2 (x)-y t1 (x) ;

[0019] Wherein, the P0 value represents the change of the defect amplitude in the t1-t2 period.

[0020] Specifically, the P0 value equal to 0 indicates that there is no new defect or the defect does not further expand in the t1-t2 period.

[0021] Specifically, the P0 value greater than 0 indicates that there is new defect or the defect has further expanded in the t1-t2 period.

[0022] The present application provides a magnetostrictive guided wave detection data temperature compensation method, which comprises the steps of collecting magnetostrictive guided wave detection data, temperature compensating the guided wave detection data, eliminating the detection data of the same pipeline at different time after temperature compensation, establishing the corresponding database of defect amplitude and defect loss amount, and establishing the corresponding relationship between defect loss amount and echo amplitude data, and generating defect evaluation database. The magnetostrictive guided wave detection data temperature compensation method with the above steps effectively solves the influence of temperature change on the detection data, avoids a large amount of additional work such as manual excavation verification, effectively improves the production efficiency and improves the detection precision, so that the positioning and quantitative analysis results of the defect are more accurate. BRIEF DESCRIPTION OF DRAWINGS

[0023] No. DETAILED DESCRIPTION

[0024] The application provides a magnetostrictive guided wave detection data temperature compensation method, which can be used for compensating the influence of temperature on magnetostrictive guided wave detection data, thereby avoiding errors in defect positioning and quantitative analysis, and guaranteeing the accuracy of magnetostrictive guided wave detection.

[0025] Embodiment one

[0026] The application provides a magnetostrictive guided wave detection data temperature compensation method, and specifically, the magnetostrictive guided wave detection data temperature compensation method comprises the following steps.

[0027] Step one: collecting magnetostrictive guided wave detection data to obtain echo reflection time t and amplitude P under actual temperature T, and calculating defect distance L according to empirical wave speed v;

[0028] The empirical wave speed v is the wave speed measured through multiple tests under reference temperature T0;

[0029] It is worth noting that the defect distance L, the empirical wave speed v and the echo reflection time t satisfy the relationship L = v·t / 2. However, since the empirical wave speed v does not eliminate the influence of temperature on wave speed, the defect distance L is not an accurate value.

[0030] Step two: performing temperature compensation on the empirical wave speed v to obtain actual wave speed v under actual temperature T T ; and correcting the defect distance L according to the actual wave speed v T to obtain actual defect distance L under actual temperature T T .

[0031] Embodiment two

[0032] The application provides a magnetostrictive guided wave detection data temperature compensation method, and specifically, the magnetostrictive guided wave detection data temperature compensation method comprises the following steps.

[0033] Step one: collecting magnetostrictive guided wave detection data to obtain echo reflection time t and amplitude P under actual temperature T, and calculating defect distance L according to empirical wave speed v;

[0034] The empirical wave speed v is the wave speed measured through multiple tests under reference temperature T0;

[0035] It is worth noting that the defect distance L, the empirical wave speed v and the echo reflection time t satisfy the relationship L = v·t / 2. However, since the empirical wave speed v does not eliminate the influence of temperature on wave speed, the defect distance L is not an accurate value.

[0036] Step two: temperature compensation for the empirical wave velocity v to obtain the actual wave velocity v under the actual temperature T T ; and according to the actual wave velocity v T , the defect distance L is corrected to obtain the actual defect distance L under the actual temperature T T .

[0037] That is, example two contains all the technical contents of example one, and on the basis of example one, the temperature compensation for the empirical wave velocity v in step two is further refined. Specifically, the temperature compensation formula is used to realize the temperature compensation for the empirical wave velocity v. The temperature compensation formula satisfies: v T =v-b(T0-T); wherein, v T is the actual wave velocity under the actual temperature T, v is the empirical wave velocity, b is the compensation coefficient, and T0 is the reference temperature.

[0038] After completing the temperature compensation for the empirical wave velocity v and obtaining the actual wave velocity v under the actual temperature T T ; the actual wave velocity v T is further used to correct the defect distance L. Specifically, the actual defect distance L under the actual temperature T T satisfies L T =v T ·t / 2.

[0039] Example three

[0040] The application provides a magnetostrictive guided wave detection data temperature compensation method. Specifically, the magnetostrictive guided wave detection data temperature compensation method comprises:

[0041] Step one: collecting magnetostrictive guided wave detection data to obtain the echo reflection time t and the amplitude P under the actual temperature T, and calculating the defect distance L according to the empirical wave velocity v;

[0042] The empirical wave velocity v is the wave velocity measured by multiple tests under the reference temperature T0;

[0043] It is worth noting that the defect distance L satisfies L=v·t / 2 among the empirical wave velocity v, the echo reflection time t, and the amplitude P. However, since the empirical wave velocity v does not eliminate the error influence of temperature on the wave velocity, this defect distance L is not an accurate value.

[0044] Step two: temperature compensation for the empirical wave velocity v to obtain the actual wave velocity v under the actual temperature T T ; and according to the actual wave velocity v T , the defect distance L is corrected to obtain the actual defect distance L under the actual temperature T T .

[0045] Further, a temperature compensation formula is used to compensate the empirical wave velocity v. The temperature compensation formula satisfies: v T =v-b(T0-T); wherein, v T is the actual wave velocity under the actual temperature T, v is the empirical wave velocity, b is the compensation coefficient, and T0 is the reference temperature. After the empirical wave velocity v is compensated and the actual wave velocity v T under the actual temperature T is obtained, the actual defect distance L T under the actual temperature T is further corrected according to the actual wave velocity v T . Specifically, the actual defect distance L T under the actual temperature T satisfies: L T =v T ·t / 2.

[0046] That is, the embodiment three contains all the technical contents of the embodiment one and the embodiment two, and further limits the two values of the temperature compensation formula in the embodiment one and the embodiment two. Specifically, the reference temperature T0 is 20℃, and the empirical wave velocity v is 3248m / s.

[0047] Embodiment four

[0048] The application provides a magnetostrictive guided wave detection data temperature compensation method. Specifically, the magnetostrictive guided wave detection data temperature compensation method comprises the following steps.

[0049] Step one: collecting magnetostrictive guided wave detection data to obtain echo reflection time t and amplitude P under the actual temperature T, and calculating defect distance L according to empirical wave velocity v;

[0050] The empirical wave velocity v is the wave velocity measured by multiple tests under the reference temperature T0;

[0051] It is worth noting that the defect distance L satisfies: L=v·t / 2, wherein v is the empirical wave velocity, and t is the echo reflection time. However, since the empirical wave velocity v does not eliminate the error influence of temperature on the wave velocity, the defect distance L is not an accurate value.

[0052] Step two: compensating the empirical wave velocity v to obtain the actual wave velocity v T under the actual temperature T; and correcting the defect distance L according to the actual wave velocity v T to obtain the actual defect distance L T under the actual temperature T.

[0053] That is, the embodiment four contains all the technical contents of the embodiment one, and further adds step three on the basis of the embodiment one.

[0054] Specifically, step three: eliminating the detection data of the same pipeline at different time after temperature compensation to obtain the change of the defect amplitude of the same pipeline at different time.

[0055] It is worth noting that the detection data of the same pipeline at different time after temperature compensation is eliminated, which aims to further eliminate the influence of temperature on the defect amplitude data and determine the change of the observed defect amplitude in this time interval.

[0056] Example five

[0057] The application provides a magnetostrictive guided wave detection data temperature compensation method, and specifically, the magnetostrictive guided wave detection data temperature compensation method comprises the following steps.

[0058] Step one: collecting magnetostrictive guided wave detection data to obtain echo reflection time t and amplitude P under actual temperature T, and calculating defect distance L according to empirical wave speed v;

[0059] The empirical wave speed v is the wave speed measured by multiple tests under the reference temperature T0;

[0060] It is worth noting that the defect distance L, the empirical wave speed v and the echo reflection time t satisfy the relationship L=v·t / 2. However, since the empirical wave speed v does not eliminate the error influence of temperature on the wave speed, the defect distance L is not an accurate value.

[0061] Step two: temperature compensation is performed on the empirical wave speed v to obtain actual wave speed v under actual temperature T T ; and according to the actual wave speed v T , the defect distance L is corrected to obtain actual defect distance L T under actual temperature T.

[0062] Step three: eliminating the detection data of the same pipeline at different time after temperature compensation to obtain the change of the defect amplitude of the same pipeline at different time.

[0063] That is, example five comprises all the technical contents of example four, and on the basis of example four, the process of eliminating the detection data of the same pipeline at different time after temperature compensation in step three is further limited, specifically:

[0064] Taking distance as the x-axis and amplitude as the y-axis, the 0 value of the y-axis as the reference line,

[0065] The change of the defect amplitude of the same pipeline at different time satisfies P0=y t2 (x)-y t1 (x);

[0066] Wherein, the P0 value represents the change of the defect amplitude in the t1-t2 time period.

[0067] It is worth noting that when the P0 value is equal to 0, it means that there is no new addition of defects or no further expansion of defects in the t1-t2 time period. When the P0 value is greater than 0, it means that there is new addition of defects or further expansion of defects in the t1-t2 time period.

[0068] Embodiment six

[0069] The present application provides a magnetostrictive guided wave detection data temperature compensation method, specifically, the magnetostrictive guided wave detection data temperature compensation method comprises:

[0070] Step one: collect magnetostrictive guided wave detection data to obtain echo reflection time t and amplitude P under actual temperature T, and calculate the defect distance L according to the empirical wave speed v;

[0071] The empirical wave speed v is the wave speed measured by multiple tests under the reference temperature T0;

[0072] It is worth noting that the defect distance L, the empirical wave speed v and the echo reflection time t satisfy: L=v·t / 2. However, since the empirical wave speed v does not eliminate the error influence of temperature on wave speed, this defect distance L is not an accurate value.

[0073] Step two: temperature compensation is performed on the empirical wave speed v to obtain the actual wave speed v under the actual temperature T T ; and according to the actual wave speed v T , the defect distance L is corrected to obtain the actual defect distance L T under the actual temperature T.

[0074] Step three: the detection data after temperature compensation at different times for the same pipeline is eliminated to obtain the change of the defect amplitude at different times for the same pipeline.

[0075] That is, embodiment six contains all the technical contents of embodiment four, and further increases step four on the basis of embodiment four. Specifically, step four is: establishing a corresponding database of defect amplitude and defect loss, and establishing a corresponding relationship between defect loss and echo amplitude data to generate a defect evaluation database.

[0076] It is worth noting that the corresponding database of defect amplitude and defect loss amount can be used to evaluate the size of the defect. After obtaining a large amount of defect loss amount and echo amplitude data corresponding relationship, a defect evaluation database can be further generated; by calling the amplitude data and the defect evaluation database, the specific situation of the defect can be determined. The query result is more accurate and reliable because it uses temperature compensation and elimination processing data processing methods to fundamentally solve the influence of temperature on wave velocity and other related data.

[0077] Embodiment seven

[0078] Embodiment seven provides a set of measured data for further explanation.

[0079] The application provides a magnetostrictive guided wave detection data temperature compensation method, and specifically, the magnetostrictive guided wave detection data temperature compensation method comprises the following steps:

[0080] Step one: collect magnetostrictive guided wave detection data to obtain echo reflection time t and amplitude P under actual temperature T, and calculate defect distance L according to empirical wave velocity v;

[0081] The empirical wave velocity v is the wave velocity measured by multiple tests under the condition of reference temperature T0;

[0082] Specifically, under the condition of medium actual temperature T of 50 DEG C at the 1# data collection point in January, the echo reflection time t is 0.01 s and the amplitude P is 0.3 v, and under the condition of medium actual temperature T of 50 DEG C at the 1# data collection point in July, the echo reflection time t is 0.01 s and the amplitude P is 0.3 v.

[0083] Step two: temperature compensation is performed on the empirical wave velocity v to obtain the actual wave velocity v under the condition of actual temperature T T ; and according to the actual wave velocity v T , the defect distance L is corrected to obtain the actual defect distance L under the condition of actual temperature T T .

[0084] Specifically, the actual defect position L T1 in January is L = (3248-0.71*50)*0.01 / 2 = 16.06 m, and the actual defect position L T2 in July is L = (3248-0.71*50)*0.01 / 2 = 16.06 m, that is, the defects found in January and July are the same position defects, that is, the same defects.

[0085] Step three: elimination processing is performed on the detection data after temperature compensation at different time points of the same pipeline to obtain the change of defect amplitude at different time points of the same pipeline.

[0086] Specifically, taking distance as x-axis, amplitude as y-axis, and 0 value of y-axis as reference line, the amplitude data obtained after temperature compensation before and after elimination processing are as follows:

[0087] P0=y t2 (x)-y t1 (x)=y t2 (16.06)-y t1 (16.06)=0.3-0.3=0;The results show that: P0 value is equal to 0, then the defect at the position of 16.06 m is not further expanded during the period from January to July.

[0088] Step four: establishing a corresponding database of defect amplitude and defect loss amount, and a corresponding relationship between defect loss amount and echo amplitude data, and generating a defect evaluation database.

[0089] Specifically, by calling the defect evaluation database, the 0.3v amplitude corresponds to a defect with a cross-sectional loss amount of 5.1%, that is, there is a defect at the position of 16.06 m, and the size of the defect is 5.1% of the cross-sectional loss amount, but it does not expand during the period from January to July.

[0090] Example eight

[0091] This example eight provides another set of measured data for further explanation and illustration.

[0092] The present application provides a magnetostrictive guided wave detection data temperature compensation method, specifically, the magnetostrictive guided wave detection data temperature compensation method comprises:

[0093] Step one: collecting magnetostrictive guided wave detection data to obtain echo reflection time t and amplitude P under actual temperature T, and calculating defect distance L according to empirical wave speed v;

[0094] The empirical wave speed v is the wave speed measured by multiple tests under the reference temperature T0;

[0095] Specifically, under the actual temperature T of 50℃ of the 1# data collection point in January, the echo reflection time t is 0.01s and the amplitude P is 0.3v, and under the actual temperature T of 40℃ of the 1# data collection point in July, the echo reflection time t is 0.00998s and the amplitude P is 0.5v.

[0096] Step two: temperature compensation is performed on the empirical wave speed v to obtain the actual wave speed v under the actual temperature T T ; and according to the actual wave speed v T , the defect distance L is corrected to obtain the actual defect distance L T under the actual temperature T.

[0097] Specifically, the actual defect distance LT1 = (3248-0.71*50)*0.01 / 2=16.06m, the actual position L of the defect in July T2 = (3248-0.71*40)*0.00998 / 2≈16.06m, that is, the defect found in January and July is the same position defect, that is, the same defect.

[0098] Step three: the same pipeline at different times of temperature compensation detection data are eliminated, and the change of the same pipeline at different times of defect amplitude is obtained.

[0099] Specifically, taking distance as the x-axis, amplitude as the y-axis, and the 0 value of the y-axis as the reference line, the amplitude data obtained before and after the elimination processing and temperature compensation:

[0100] P0=y t2 (x)-y t1 (x)=y t2 (16.06)-y t1 (16.06)=0.5-0.3=0.2; the result shows that: P0 value is greater than 0, then in 1-7 month, the defect at the position of 16.06m has further expansion.

[0101] Step four: a corresponding database of defect amplitude and defect loss is established, and a corresponding relationship between defect loss and echo amplitude data is established, and a defect evaluation database is generated.

[0102] Specifically, by calling the defect evaluation database, the 0.2v amplitude corresponds to the defect with a cross-sectional loss of 3.4%, that is, there is a defect at the position of 16.06m, and the size of the defect is 5.1% of the cross-sectional loss, and further expansion occurs during 1-7 month, and the defect expansion size is 3.4% of the cross-sectional loss.

[0103] The application provides a magnetostrictive guided wave detection data temperature compensation method, which comprises the steps of collecting magnetostrictive guided wave detection data, temperature compensating the guided wave detection data, eliminating the same pipeline at different times of temperature compensation detection data, establishing a corresponding database of defect amplitude and defect loss, and establishing a corresponding relationship between defect loss and echo amplitude data, and generating a defect evaluation database. The magnetostrictive guided wave detection data temperature compensation method with the above steps effectively solves the influence of temperature change on the detection data, avoids a large amount of additional work such as manual excavation verification, effectively improves the production efficiency and improves the detection precision, so that the positioning and quantitative analysis results of the defect are more accurate.

[0104] The above merely illustrates the specific embodiments of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of the changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A magnetostrictive waveguide detection data temperature compensation method, characterized by, Comprising the following steps: Step one: Collect magnetostrictive guided wave detection data, get echo reflection time t and amplitude P under actual temperature T, and calculate defect distance L according to empirical wave speed v; Empirical wave speed v is the wave speed measured by multiple tests under reference temperature T0; Step two: temperature compensation is performed on the empirical wave velocity v to obtain the actual wave velocity v under the actual temperature T T ; and according to the actual wave velocity v T , the defect distance L is corrected to obtain the actual defect distance L under the actual temperature T T ; The process of temperature compensation of empirical wave speed v in the step two can be specifically described as: temperature-compensating the empirical wave velocity v using a temperature compensation formula; the temperature compensation formula satisfies: v T = v - b (T0 - T); where v T is the actual wave velocity at the actual temperature T, v is the empirical wave velocity, b is a compensation factor, and T0 is a reference temperature. the actual defect distance L at the actual temperature T T , satisfies L T = v T · t / 2.

2. The magnetostrictive waveguide temperature compensation method for detecting data according to claim 1, wherein, Further comprising the following steps: Step three: Eliminate the temperature-compensated detection data of the same pipeline at different times to obtain the change of defect amplitude of the same pipeline at different times.

3. The magnetostrictive waveguide temperature compensation method of claim 2, wherein, Further comprising the following steps: Step four: Establish a corresponding database of defect amplitude and defect loss, and establish a corresponding relationship between defect loss and echo amplitude data, and generate a defect evaluation database.

4. The magnetostrictive waveguide temperature compensation method for detecting data according to claim 1, wherein, The reference temperature T0 is 20℃, and the empirical wave speed v is 3248m / s.

5. The magnetostrictive waveguide temperature compensation method for detecting data according to claim 2, wherein, The process of eliminating the temperature-compensated detection data of the same pipeline at different times in the step three can be specifically described as: With the actual defect distance as the x-axis, the amplitude as the y-axis, the 0 value of the y-axis as the reference line, the change of the defect amplitude of the same pipeline at different times satisfies: P0=y t2 (x)-y t1 (x); Wherein, the P0 value represents the change of defect amplitude in the t1-t2 time period.

6. The magnetostrictive waveguide temperature compensation method of claim 5, wherein, The P0 value equal to 0 indicates that there is no new defect or the defect does not further expand in the t1-t2 time period.

7. The magnetostrictive waveguide temperature compensation method of claim 5, wherein, The P0 value greater than 0 indicates that there is new defect or the defect has further expanded in the t1-t2 time period.