CN-122017019-A - Method for recognizing flaw detection sensitivity change by ultrasonic wave through interface wave

CN122017019ACN 122017019 ACN122017019 ACN 122017019ACN-122017019-A

Abstract

The invention discloses a method for identifying flaw detection sensitivity change by ultrasonic wave through interface wave, which belongs to the technical field of nondestructive detection, and comprises the steps of firstly setting initial reference height of primary interface wave, the real-time height of the primary interface wave of the multiple channels is collected in real time in the flaw detection process, and the sensitivity attenuation of each channel is calculated by utilizing a decibel difference value algorithm. Further, through statistical analysis of arithmetic mean value and standard deviation of multi-channel data, the attenuation amount is logically compared with a preset threshold value, namely, the attenuation amount is judged to be systematic coupling deterioration when the mean value exceeds the standard and the consistency is good, the whole cleaning is triggered, the attenuation amount is judged to be local fault when the consistency is poor due to the fact that specific channel attenuation exists, and an abnormal probe is positioned. According to the invention, sensitivity monitoring is changed from off-line verification to on-line real-time monitoring, so that the coupling water quality problem and single probe faults can be accurately distinguished, the batch missing detection risk is effectively avoided, and the quality control level and the production efficiency of flaw detection operation are improved.

Inventors

ZHU XIAODONG
WANG YUNYUN
ZHU XINWEI
CHEN BINGHUA

Assignees

江苏常宝普莱森钢管有限公司

Dates

Publication Date: 20260512
Application Date: 20260202

Claims (10)

1. A method for identifying flaw detection sensitivity change by ultrasonic waves through interface waves, which is characterized by comprising the following steps: Before the flaw detection operation starts, setting an initial reference height of the primary interface wave amplitude, and taking the initial reference height as an initial reference zero point of the system sensitivity; the real-time monitoring and data acquisition of the multi-channel interface wave comprises the steps of locking and acquiring the real-time height of the primary interface wave of a detection channel in real time in the flaw detection process; The independent calculation step of the channel sensitivity attenuation amount comprises the steps that a data processing and control unit calculates the sensitivity attenuation amount at the current moment by utilizing a decibel difference algorithm according to the preset initial reference height and the real-time primary interface wave height acquired in real time; And a logic comparison step of a critical threshold value, namely comparing the calculated sensitivity attenuation amount with a preset alarm threshold value, judging that the sensitivity of the system is reduced to the critical point when the sensitivity attenuation amount reaches or exceeds the alarm threshold value, and generating a corresponding state control signal.
2. The method for recognizing a change in flaw detection sensitivity by an interfacial wave by an ultrasonic wave according to claim 1, wherein in the independent calculation step of the channel sensitivity attenuation amount, the sensitivity attenuation amount is calculated by: Calculating the ratio of the initial reference height to the real-time primary interface wave height, taking the logarithm of the ratio with the base of ten, and multiplying the logarithm by twenty to obtain the sensitivity attenuation; the alarm threshold is set to six decibels, the alarm threshold corresponding to a fifty percent of the real-time primary interface wave height falling to the initial reference height.
3. The method for identifying changes in flaw detection sensitivity by interfacial waves using ultrasonic waves according to claim 1, wherein said system initialization and reference sensitivity calibration steps specifically comprise: under the state that the rotating head stably operates and the coupling water layer is established, the gain of the detection channel is adjusted by using a standard sampling tube; The primary interface wave amplitude of the detection channel in the defect-free region is normalized to eighty percent of full screen amplitude by adjusting a digital display gain or waveform scaling factor to establish the initial reference height as eighty percent of full screen amplitude.
4. The method for identifying flaw detection sensitivity change by interface wave according to claim 1, wherein the steps of multi-channel interface wave real-time monitoring and data acquisition specifically comprise: setting an interface wave tracking gate in the A-scan time domain waveform, wherein the interface wave tracking gate is independent of a flaw detection gate for detecting flaw waves; The data processing and control unit performs wave crest searching in a time window of the interface wave tracking gate, and locks the maximum value in a single pulse repetition frequency period as the real-time height of the primary interface wave; and carrying out moving average calculation on the real-time heights of the primary interfacial waves for a plurality of continuous periods, and taking the calculated arithmetic average value as an effective measurement value.
5. The method for recognizing a change in flaw detection sensitivity by interfacial waves according to claim 1, wherein said ultrasonic automatic flaw detection system comprises a plurality of independent ultrasonic probes, each of said ultrasonic probes corresponding to an independent signal detection channel; the independent calculation of the channel sensitivity attenuation is specifically performed by calculating the sensitivity attenuation of each signal detection channel relative to an initial state; after the independent calculation step of the channel sensitivity attenuation amount, the method further comprises the step of comparing the statistic analysis and the difference of the multi-channel data, wherein the statistic feature extraction is carried out on the sensitivity attenuation amounts of all the signal detection channels at the same time, and the arithmetic mean value and the standard deviation are calculated.
6. The method for identifying changes in flaw detection sensitivity by interfacial waves using ultrasound according to claim 5, wherein in said step of comparing statistical analysis and difference of said multi-channel data: the arithmetic average value is calculated by summing the sensitivity attenuation amounts of all the signal detection channels and dividing the sum by the total number of the signal detection channels; The standard deviation is calculated by calculating the difference between the sensitivity attenuation and the arithmetic mean value for each signal detection channel, summing the squares of the differences corresponding to all the signal detection channels, dividing the sum by the total number of the signal detection channels to obtain a variance, and finally performing an evolution operation on the variance to obtain the standard deviation.
7. The method of claim 6, further comprising an intelligent decision and classification response strategy step, wherein the intelligent decision and classification response strategy step specifically implements a first decision logic: comparing the arithmetic mean value with a global alarm threshold value, and comparing the standard deviation with a consistency tolerance threshold value; When the arithmetic mean value is greater than or equal to the global alarm threshold and the standard deviation is less than the consistency tolerance threshold, determining that the current state is in a systematic coupling degradation state; the data processing and control unit generates a system maintenance instruction, controls the flaw detection line to stop running and prompts the whole cleaning and water changing of the coupling water cavity of the rotating head.
8. The method of claim 7, wherein the intelligent decision and classification response strategy step further performs a second decision logic: When the condition of the first judgment logic is not met, screening all the signal detection channels of which the sensitivity attenuation is greater than or equal to the global alarm threshold value, and recording corresponding channel indexes; If at least one channel index exists, judging that the current local fault state exists; The data processing and control unit generates a channel inspection instruction, outputs the channel index and prompts inspection for a specific probe.
9. The method for recognizing flaw detection sensitivity change by ultrasonic waves through interfacial waves according to claim 1, wherein the ultrasonic automatic flaw detection system adopts a rotary head water immersion detection mode, and a rotary head coupling water cavity for accommodating coupling medium is arranged in the rotary head; The independent calculation step of the channel sensitivity delta attenuation is used for monitoring the reduction of the acoustic energy transmission efficiency caused by the accumulated oxide scale and dust of the coupling water in the coupling water cavity of the rotating head.
10. The method of claim 8, wherein after performing the operation corresponding to the system maintenance instruction or the channel inspection instruction, the method further comprises the step of restoring and recalibrating: Forcing the standard sample tube to be re-introduced; And after confirming that the primary interface wave amplitudes of all the detection channels are restored to be near the initial reference height, resetting the alarm state and unlocking the system.

Description

Method for recognizing flaw detection sensitivity change by ultrasonic wave through interface wave Technical Field The invention relates to the technical field of nondestructive testing, in particular to a method for recognizing flaw detection sensitivity change by ultrasonic waves through interfacial waves. Background In the metallurgical industry and the oil gas conveying field, the internal quality control of steel pipe products is a key link for guaranteeing engineering safety. The ultrasonic automatic flaw detection technology is widely applied to the quality inspection process before the delivery of the steel pipe due to the characteristics of high detection speed, high sensitivity, sensitivity to defects such as internal cracks and the like. In particular to a water immersion ultrasonic detection system adopting a rotary probe structure, water is used as a coupling medium for ultrasonic wave propagation, and full coverage scanning of a pipe body can be realized through the composite motion of high-speed rotation of a probe around a steel pipe and straight forward movement of the steel pipe, so that the ultrasonic detection system is main flow detection equipment on the existing steel pipe automatic production line. In the existing ultrasonic automatic flaw detection operation flow, ensuring that the sensitivity of a flaw detection system is always in the range specified by the standard is a core premise for ensuring the reliability of detection results. In general, an off-line calibration mode based on a fixed time interval is commonly used in an industrial field to control sensitivity, that is, before each production shift starts or every set period of time (for example, every 4 hours), an operator sends a sample tube prefabricated with a standard artificial defect (such as a notch or a through hole) into a flaw detection device, and adjusts or confirms the emission voltage and the receiving gain of an instrument according to the echo amplitude of the artificial defect. And after the primary verification is qualified and until the period of time before the next verification, the acoustic performance of the default equipment of the system is maintained in a state during calibration, and the circulating water system is continuously utilized to establish a coupling layer for detecting the batch of steel pipes. However, the offline verification mode based on the fixed time interval has obvious hysteresis defect in practical application, and is difficult to adapt to complex working condition changes in the continuous production process. Because the coupling water environment in the rotary head is not constant, as a large number of steel pipes with oxide skin, rust or greasy dirt continuously pass through the flaw detection host machine, the fallen impurities can be gradually mixed into circulating water to increase turbidity or directly attached to the radiation surface of the probe, and the physical factors can lead to unpredictable attenuation of the transmission efficiency of ultrasonic waves in the medium. Because the prior art lacks the real-time on-line monitoring means aiming at the acoustic energy transmission efficiency in the flaw detection process, once serious coupling water quality deterioration occurs in the interval period of two manual checks, the equipment cannot sense and respond in time and still can maintain the original gain parameter operation, so that the steel pipe detected in the time period is in a state with insufficient sensitivity in practice, batch defect missed detection accidents are extremely easy to occur, and the quality hidden trouble is usually discovered afterwards only when the next pipe check fails, thereby causing a large amount of reworking and re-detection and productivity loss. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a method for identifying flaw detection sensitivity change of ultrasonic waves through interface waves, which solves the problems that an ultrasonic automatic flaw detection system relies on a fixed time interval to calibrate sensitivity, cannot monitor sensitivity reduction caused by coupling water quality deterioration in real time, and cannot distinguish systematic coupling environment deterioration from single-channel probe faults, thereby increasing flaw detection risk or reducing production efficiency. In order to achieve the above object, the present invention is realized by a method for recognizing a flaw detection sensitivity change of ultrasonic waves through interface waves, which is applied to an ultrasonic automatic flaw detection system including a data processing and control unit, comprising the steps of: Before the flaw detection operation starts, setting an initial reference height of the primary interface wave amplitude, and taking the initial reference height as an initial reference zero point of the system sensitivity; the real-time monitoring and data acquisition of the multi-chann