RU2690975C1 - Method of determining signal from pipe wall according to power lines statistics pid cd data - Google Patents

Abstract

FIELD: defectoscopy.SUBSTANCE: use to detect pipeline defects by ultrasonic intratubular defect detector data. Summary of invention consists in the fact that for analysis of ultrasonic signals reflected from the wall of the pipeline, generating a frequency map of responses of ultrasonic signals reflected from the internal wall of the pipeline, excluding noise component of ultrasonic signal reflected from internal wall of pipeline, setting of threshold values of ultrasonic signal reflected from internal wall of pipeline, determining pipeline regions with low frequency of ultrasonic signals reflected from the internal wall of the pipeline or with absence of ultrasonic signals reflected from the internal wall of the pipeline, smoothing the prepared reflected from the internal wall of the pipeline of ultrasonic signals, using a moving average filter in order to reduce the level and frequency of emissions of ultrasonic signals reflected from the inner wall of the pipeline with a low signal / noise ratio, generating power lines of ultrasonic signals reflected from the inner wall of the pipeline; the obtained power lines of the ultrasonic signals reflected from the inner wall of the pipeline are considered to be the zone of beginning of the inner surface of the pipeline.EFFECT: high accuracy of determining defects located inside a wall of a pipeline, such as longitudinal and transverse stress-corrosion cracks of walls of a pipeline, including in longitudinal and transverse welds.1 cl

Description

The invention relates to the field of ultrasonic non-destructive testing of materials and products, and can be used to identify defects in the pipeline according to the ultrasonic in-line defectoscope.

A known system and method for the implementation of ultrasonic measurement of the properties of the wall of the pipeline (patent RU 2573712, IPC G01N 29/04, priority from 07.10.2011). The essence of the invention lies in the fact that the measured wall thickness of the pipeline as a function of position using the propagation of ultrasound. A series of predictive models are used that predict ultrasound response signals as a function of different sets of parameters that are decisive for ultrasound velocity, depending on position, at different sound frequencies and different spatial resolution. Serial fitting processes are performed, each of which fits a combination of the values of a sequential set of parameters to the detected ultrasonic response signals in accordance with the respective model, using the fitted values from the previous fitting process to initialize the next set of parameters for the iterative fitting. At least the first model sets the predictions of wave vector values as a function of the peripheral position in successive rings around the specified tube as sums of wave vector values for the peripheral positions in the previous ring multiplied by the propagation coefficients using propagation coefficients depending on the first set of parameters.

The disadvantage of this method is the narrow scope of the invention - control of the wall thickness of the pipeline.

A known method of measuring corrosion of pipe pipelines (patent RU 2451932, IPC G01N29 / 07, G01N29 / 11, priority from 10/07/2011) To measure corrosion on a pipe, reversible piezoceramic pickup sources are installed and they use longitudinal sound wave signals . The method of mathematical analysis of signals determines the speed and attenuation of sound in a pipe, and from them, calculate the thickness of the corrosion layer of a dedicated pipe section between adjacent receiving emitters. Technological noise of the pumped product is used as a sound signal source, and on the pipeline that is turned off for prevention, active noise-like sounding packages are used, which are computer-generated and emit piezoceramic transceivers.

The disadvantage of this method is the narrow scope of the invention - the measurement of corrosion on the pipe pipeline.

The known method of ultrasonic testing (patent RU 2596242, IPC G01N 29/04, priority from 06.25.2015). The essence of the invention lies in the fact that a pulse of a longitudinal wave, which falls on the surface of the test object at an angle, whose value is greater than the first critical angle and less than the second critical angle, is excited with the help of an ultrasonic transducer and analyzes the amplitude of the recorded echoes. According to the invention, in order to increase the reliability of the estimation of the depth of defects, the angle of incidence of ultrasonic pulses on the surface of the test object is measured, the amplitude of the largest echo signal and the amplitude of the echo signal are measured at an input angle of 45 ... 50 °, and the depth of the defect is judged by the difference in the measured amplitudes. EFFECT: increased reliability of diagnostic data when assessing the depth of small pipeline cracks in the process of ultrasonic non-destructive testing.

The disadvantage of this method is the narrow scope of the invention - the assessment of the depth of small cracks in the pipeline.

Known inline ultrasonic flaw detector (patent RU 2626744, IPC G01N 29/04, priority from 05.24.2016). The essence of the invention lies in the fact that the in-tube ultrasonic flaw detector is equipped with a device for measuring the speed of sound in the pumped liquid V and an automatic adjustment unit for the duration of the time window ΔT during the control according to the formula:

ΔT = ΔT ° V ° / V, where

ΔТ ° - the duration of the window when tested in a liquid with a minimum sound velocity V °. The design of the carrier and ultrasonic piezoelectric transducers provides the path length of the ultrasonic pulse, from the reflection point from the inner surface of the pipe to the nearest carrier element, not less than ΔТ ° V ° / 2 + ΔНп, where ΔНп is the maximum allowable wear of the skid of the carrier of ultrasonic piezoelectric transducers. EFFECT: expansion of the range of monitored pipe wall thicknesses in the direction of increasing when pumping dissimilar liquids and simplifying the requirements for the design of the carrier of ultrasonic piezoelectric transducers.

The disadvantage of this method is the narrow scope of the invention - control of the wall thickness of the pipeline.

The closest to the claimed method is the method of in-line ultrasonic testing (patent RU 2607258, IPC G01N 29/07, priority from 11.08.2015). The essence of the invention is that using ultrasonic transducers excite pulses of an elastic wave in the fluid pumped through the pipeline at a predetermined angle to the internal surface of the pipeline during the movement of the detector and against movement of the detector through equal intervals of the path traveled, analyze the echo pulses from the pipe wall, amplitude which exceeded the specified threshold level, while measuring the time of registration of the greatest echo pulse after each excitation of the ultrasound of the transducer, and the defect is considered registered, if during not less than three consecutive excitations of the ultrasonic transducer emitting ultrasonic pulses in the direction of the detector, the recording time of the echo pulse is constantly reduced, or at the ultrasonic transducer emitting against the movement of the flaw detector, the recording time of the echo -pulse is constantly increasing. Technical result: increase the reliability of detection of defects.

The disadvantage of in-line ultrasonic testing is that the method allows you to register the location of the defect, but does not give a reliable picture of the parameters of the defect.

The technical result of the claimed invention is to improve the accuracy of determining defects located inside the pipeline wall, such as: longitudinal and transverse stress-corrosion cracks in the walls of the pipeline, including in longitudinal and transverse welded seams.

The technical result is achieved by the fact that, when passing inside the pipeline, the in-line inspection device CD (Crack Detection-Crack Detector) (hereinafter referred to as VIP CD) emits ultrasonic signals. The ultrasonic signals reflected from the inner wall of the pipeline are recorded by the electronic equipment of the VIP CD and recorded on the internal information carrier installed on the VIP CD, then the arrival time of the ultrasonic signal reflected from the internal wall of the pipeline is determined. Why use a workstation with a terminal designed to upload data from internal storage media.

The ultrasonic signals reflected from the pipeline wall are analyzed as follows:

- form a frequency map of the responses of ultrasonic signals reflected from the inner wall of the pipeline;

- exclude the noise component of the ultrasonic signal reflected from the inner wall of the pipeline;

- set the threshold values of the ultrasonic signal reflected from the inner wall of the pipeline;

- determine the areas of the pipeline with a low frequency of ultrasonic signals reflected from the inner wall of the pipeline, or with no ultrasonic signals reflected from the internal wall of the pipeline;

- produce smoothing prepared by the reflected from the inner wall of the pipeline ultrasonic signals;

- use a moving average filter in order to reduce the level and frequency of emissions of ultrasonic signals reflected from the inner wall of the pipeline with a low signal-to-noise ratio;

- form the energy lines reflected from the inner wall of the pipeline ultrasonic signals, for which carry out the correlation analysis reflected from the inner wall of the pipeline ultrasonic signals of the pipeline in the plane of a single ultrasonic piezoelectric transducer;

- perform a search in order to search for ultrasonic signals reflected from the inner wall of the pipeline with a maximum value and a normal distribution of ultrasonic signals reflected from the inner wall of the pipeline in the maximum area;

- search for potential energy lines reflected from the inner wall of the pipeline ultrasonic signals, for which use the areas of the maximum previously detected reflected from the inner wall of the pipeline ultrasonic signals;

- form the final energy lines reflected from the inner wall of the pipeline ultrasonic signals, for which use the statistical information of the identified potential energy lines;

- the received energy lines reflected from the inner wall of the pipeline of ultrasonic signals are considered as the zone of the beginning of the inner surface of the pipeline.

The invention allows to determine the arrival time of ultrasonic signals reflected from the inner wall of the pipeline according to the VIP CD statistics of energy lines. The results of the invention improve the accuracy of detection of defects located inside the pipeline wall, such as: longitudinal and transverse stress-corrosion cracks of the pipeline walls, including in longitudinal and transverse welded joints, including an assessment of the geometric parameters of defects, localization of defects, search for the weld area pipeline, searching for the physical angle of the ultrasonic piezoelectric transducer signal.

Implementation of the invention:

When in-line diagnostics of a pipeline using VIP CD, ultrasonic piezoelectric transducers mounted around the VIP CD excite elastic wave pulses in the fluid pumped through the pipeline at a predetermined angle to the internal surface of the pipeline at equal intervals of the path traveled. An on-board information carrier VIP CD records an array of all ultrasonic signals reflected from the inner wall of the pipeline.

To obtain reliable information about the technical condition of the pipeline, as well as to reduce the amount of information about the pass VIP CD to be stored, it is necessary to exclude from the array of all ultrasonic signals reflected from the inner wall of the pipeline ultrasonic signals, such as the noise component of ultrasonic signals. Ultrasonic signals always have some noise component, to identify which, with the subsequent exclusion from the array of information to be stored on the VIP CD, use the claimed method.

Claims (1)

The method of determining the signal from the pipe wall according to the VIP CD statistics of energy lines, in which the in-line inspection device emits ultrasonic signals, characterized in that to analyze the ultrasonic signals reflected from the pipeline wall, they form a frequency map of the responses of ultrasonic signals reflected from the internal pipe wall reflected from the inner wall of the pipeline ultrasonic signal, set the threshold values reflected from the inner wall Ultrasonic signal pipelines, areas of the pipeline with low frequency ultrasonic signals reflected from the internal wall of the pipeline or with no ultrasonic signals reflected from the internal wall of the pipeline, smoothing the prepared ultrasonic signals reflected from the internal wall of the pipeline, using a moving average filter to reduce the level and frequency emissions reflected from the inner wall of the pipeline ultrasonic signals with a low ratio ignal / noise, form the energy lines of ultrasonic signals reflected from the inner wall of the pipeline, for which they carry out a correlation analysis of ultrasonic signals of the pipeline reflected from the inner wall of the pipeline in the plane of a single ultrasonic piezoelectric transducer, search for reflected ultrasonic signals reflected from the inner wall with a maximum value and normal distribution ultrasonic signals reflected from the inner wall of the pipeline in the region maximum, they search for potential energy lines of ultrasonic signals reflected from the inner wall of the pipeline, for which they use maximum areas of ultrasonic signals that were previously detected from the internal wall of the pipeline, then they form the final energy lines of ultrasonic signals reflected from the internal wall of the pipeline, for which they use the statistical information of the detected potential energy lines reflected from the inner wall of the ultrasonic pipeline signals; The obtained energy lines reflected from the inner wall of the pipeline ultrasonic signals are considered the zone of the beginning of the inner surface of the pipeline.