Elastic Wave Attenuation Evaluation Using B1 Echo
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing pulse echo method for evaluating defects in long objects, such as pipelines, faces challenges in accurately determining the degree and size of defects when only the B1 echo can be measured due to high elastic wave attenuation or structural factors, leading to errors in distance-amplitude characteristic curves.
Innovation Solution
An evaluation method that determines the attenuation rate of the elastic wave based on the transmission wave amplitude and the first reflected wave amplitude from a specific portion of the long object, creating a distance-amplitude characteristic curve to accurately evaluate defects, even when only the B1 echo is measurable.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the B2 echo is used to correct the distance-amplitude characteristic curve, then the accuracy of attenuation evaluation is improved, but the method becomes inapplicable when only B1 echo can be measured due to high attenuation
Solution Approach 1:
The invention extracts and eliminates the transmission loss component from the distance-amplitude characteristic curve correction process. By separating the transmission loss (probe-to-specimen and specimen-to-probe interface losses) from the attenuation evaluation, the method can use only the B1 echo to accurately evaluate attenuation without requiring the B2 echo, thus resolving the contradiction between accuracy and applicability in high attenuation environments
Solution Approach 2:
The invention changes the parameter used for correction from B2 echo amplitude to transmission loss characteristics obtained through calibration. By measuring and correcting for transmission loss separately using calibration blocks, the method transforms the correction approach to work effectively even when B2 echo cannot be measured, enabling accurate attenuation evaluation in high attenuation conditions
2Measurement precision
If the distance-amplitude characteristic curve is created using calibration block, then the measurement system sensitivity is adjusted, but errors occur when transmission loss differs between test body and calibration block
Solution Approach 1:
The invention introduces a feedback mechanism where the transmission loss is measured and corrected based on the comparison between calibration block measurements and actual test body measurements. The system continuously adjusts for transmission loss variations by using the calibration data as a reference and applying corrections to the distance-amplitude characteristic curve, thereby maintaining reliable evaluation accuracy even when transmission loss conditions differ
Solution Approach 2:
The invention uses the calibration block as an intermediary to characterize and quantify the transmission loss. By measuring the B1 echo from the calibration block and calculating the transmission loss, the system creates a mediator parameter that can be applied to correct measurements from different test bodies, eliminating the direct dependence on matching transmission loss conditions between calibration and testing
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method enables precise evaluation of the reflected wave and accurate distance-amplitude characteristic curves, effectively eliminating the influence of transmission loss and properly assessing elastic wave attenuation, thereby reducing errors in defect evaluation.
Implementation Method 1
an elastic wave in an ultrasonic range is emitted into a test object, a reflected wave reflected from a defective portion such as a flaw is detected
Implementation Method 2
a reflected wave reflected from a defective portion such as a flaw is detected
Implementation Method 3
there is used a pulse echo method which uses an elastic wave in order to detect a flaw or a defect of a long object
Data Source
AI summary
A method capable of accurately evaluating a reflected wave by properly evaluating an attenuation rate of an elastic wave without being influenced by a transmission loss in each of transmission and reception. In an evaluation method of a reflected wave for evaluating, in a long object, the presence or absence and the size of a defect of the long object by transmitting an elastic wave propagating in a longitudinal direction of the long object and receiving a reflected wave of the elastic wave, the size of the defect is evaluated by determining an attenuation rate α1 of the elastic wave based on an environment in which the long object is installed from a transmission wave amplitude At of the elastic wave and a first reflected wave amplitude Ar from a specific portion of the long object serving as a reference, creating a distance-amplitude characteristic curve of the reflected wave by using the attenuation rate α1, and comparing the distance-amplitude characteristic curve with the reflected wave amplitude.