CN116299721A - PCCP broken wire multichannel electromagnetic detection system and method - Google Patents

Abstract

The invention provides a PCCP broken wire multichannel electromagnetic detection system and a method, wherein the system comprises the following steps: the industrial control computer is used for installing detection software and controlling the whole detection process; the transmitter is used for generating an alternating current signal and driving the excitation probe to generate a primary field electromagnetic signal; the excitation probe is used for generating a primary field electromagnetic signal; the detection probe group is used for responding to the primary field electromagnetic signals, passing through the pipe wall of the PCCP pipe and the secondary field electromagnetic signals induced by the prestressed steel wire and generating voltage signals; the multichannel receiver is used for carrying out digital processing on the received voltage signals and generating digital signals; and the quadrature incremental encoder is used for generating quadrature pulse signals and obtaining displacement data according to pulse signal counting. The invention carries out multi-channel electromagnetic detection on the PCCP pipeline through the transceiver probe array with one transmitter and multiple receivers, has the functions of PCCP broken wire quantity detection and axial and circumferential positioning, and can improve the broken wire detection accuracy of the PCCP pipeline.

Description

A PCCP broken wire multi-channel electromagnetic detection system and method

technical field

The invention relates to the technical field of electromagnetic detection of PCCP broken wires, in particular to a multi-channel electromagnetic detection system and method for PCCP broken wires.

Background technique

PCCP is "Prestressed Steel Cylinder Concrete Pipe". Because of its large diameter, high strength, high pressure resistance, high sealing and superior reliability, durability, earthquake resistance and low operation and management costs, it has been well received at home and abroad. widely used. PCCP pipelines have certain security risks. A large number of operation practices at home and abroad show that the operation safety of PCCP projects has obvious characteristics: as time goes by, due to the influence of mortar protective layer defects, soil penetration corrosion, hydrogen embrittlement of steel wires, internal high pressure or overload factors, prestressed The steel wire will be broken, which will reduce the strength of the pipeline, which will cause a pipeline burst accident.

In the existing PCCP broken wire electromagnetic detection technology, PCCP broken wire single-channel electromagnetic detection technology is generally used. Due to the influence of inherent random system noise, the accuracy of broken wire detection is low, and the single-channel technology can only detect PCCP broken wire. Quantity and axial positioning.

Contents of the invention

Therefore, the technical problem to be solved by the present invention is to overcome the defect of low accuracy rate of single-channel detection of PCCP broken wires in the prior art, thereby providing a multi-channel electromagnetic detection system and method for PCCP broken wires. The array performs multi-channel electromagnetic detection on PCCP pipelines, and has the functions of detecting the number of PCCP broken wires and positioning axially and circumferentially, which can improve the accuracy of broken wire detection of PCCP pipelines.

The technical scheme that the present invention solves the problems of the technologies described above is as follows:

In a first aspect, the present invention provides a multi-channel electromagnetic detection system for PCCP broken wires, said system comprising: an industrial computer, a transmitter, an excitation probe, a detection probe set, a multi-channel receiver, and an orthogonal incremental encoder;

The industrial computer is used to install detection software, send control instructions to the transmitter, receive the quadrature pulse signal of the quadrature incremental encoder to calculate displacement data, and receive the digital signal of the multi-channel receiver for identification and storage, and analyze and calculate according to the digital signal, and judge the number of PCCP broken wires, axial positioning and circumferential positioning;

The transmitter includes a signal generator and a driver, the signal generator is used to generate an AC signal according to the first control instruction, and the driver is used to drive the excitation probe based on the AC signal to generate a primary field electromagnetic signal;

The detection probe group is used to respond to the secondary field electromagnetic signal induced by the primary field electromagnetic signal through the pipe wall and prestressed steel wire of the PCCP pipeline, generate a voltage signal based on the secondary field electromagnetic signal and transmit it to the multi-channel receiver;

The multi-channel receiver performs digital processing on the received voltage signal and generates a digital signal.

The PCCP broken wire multi-channel electromagnetic detection system provided by the embodiment of the present invention controls the entire detection process through an industrial computer, including receiving the quadrature pulse signal of the quadrature incremental encoder to calculate the displacement data of the system, and controlling the transmitter during the system movement. Generate an AC signal and generate a primary field electromagnetic signal by stimulating the probe, and detect the probe group to respond to the primary field electromagnetic signal and generate a voltage signal through the secondary field electromagnetic signal induced by the PCCP pipe wall and prestressed steel wire, and the industrial control computer receives multi-channel The receiver digitally processes the voltage signal to obtain a digital signal, and judges the number of PCCP broken wires, axial positioning and circumferential positioning according to the digital signal. The invention conducts multi-channel electromagnetic detection on the PCCP pipeline through a sending and receiving probe array, has the functions of detecting the number of PCCP broken wires and positioning in the axial and circumferential directions, and can improve the detection accuracy of the broken wires of the PCCP pipeline.

Optionally, the set of detection probes includes: multiple sets of detection probes, each probe is arranged parallel to the axial direction of the pipeline to be tested and evenly arranged along the circumferential direction of the PCCP pipeline, and is vertically arranged in space with the excitation probes.

The invention implements multi-channel electromagnetic detection on the PCCP pipeline by constructing a sending and receiving probe array, which includes an excitation probe and multiple sets of detection probes. The excitation probe and each detection probe are vertically arranged in space, which can reduce the direct coupling interference of the excitation probe. In addition, setting the detection probes parallel to the axial direction of the pipeline to be tested can receive more eddy current magnetic flux on the pipe wall and improve the detection sensitivity; uniformly set along the PCCP pipeline circumferential direction can make the relative positions of each detection probe different from the place where the broken wire occurs, Thereby, different voltage signals are induced, and the analysis and calculation are carried out according to the difference of the voltage signals, so as to realize the circumferential positioning of PCCP broken wires.

In the second aspect, the embodiment of the present invention provides a PCCP broken wire multi-channel electromagnetic detection method, comprising the following steps:

S1: The PCCP broken wire multi-channel electromagnetic detection system acquires displacement data through an orthogonal incremental encoder during the movement process, and the excitation probe generates a primary field electromagnetic signal according to the AC signal emitted by the transmitter;

S2: the detection probe group responds to the primary field electromagnetic signal through the PCCP pipe wall and the secondary field electromagnetic signal induced by the prestressed steel wire and generates a voltage signal;

S3: The multi-channel receiver generates a digital signal by digitizing the received voltage signal, and sends the digital signal to an industrial computer;

S4: The industrial control computer stores the received digital signal into the buffer, and identifies the digital signal. If the preset digital feature at the PCCP pipe interface is not recognized, repeat S1-S3. If the digital signal is recognized, The preset digital feature stores the digital signal in the buffer to a local memory;

S5: Repeat S1-S4 according to the displacement data until the detection of all the pipe joints of the PCCP pipeline is completed, and judge the number of PCCP broken wires, axial positioning and circumferential positioning according to the detection results.

In the PCCP broken wire multi-channel electromagnetic detection method provided by the embodiment of the present invention, the primary field electromagnetic signal is generated by the excitation probe according to the AC signal of the transmitter, and the detection probe group responds to the primary field electromagnetic signal through the pipe wall of the PCCP pipeline and the prestressed steel wire. The secondary field electromagnetic signal and generate a voltage signal, the multi-channel receiver receives the voltage signal and digitizes it, then sends the obtained digital signal to the industrial control computer, the industrial control computer identifies and stores the digital signal, and through the orthogonal incremental encoding The device realizes the detection of all pipe joints, and judges the number of PCCP broken wires, axial positioning and circumferential positioning according to the detection results. The invention conducts multi-channel electromagnetic detection on the PCCP pipeline through a sending and receiving probe array, has the functions of detecting the number of PCCP broken wires and positioning in the axial and circumferential directions, and can improve the detection accuracy of the broken wires of the PCCP pipeline.

Optionally, the detection system performs multi-channel electromagnetic detection of broken wires by moving in the PCCP pipeline.

The detection system of the present invention completes the detection of broken wires at different positions by moving along the PCCP pipeline. During the movement process, the excitation probe continuously generates a primary field electromagnetic signal, and the detection probe responds to the primary field electromagnetic signal through the wall of the PCCP pipeline. Combined with the secondary field electromagnetic signal induced by the prestressed steel wire to generate a voltage signal, the voltage signal at each position contains the broken wire information of the entire PCCP pipeline.

Optionally, the process of acquiring displacement data includes: the PCCP broken wire multi-channel electromagnetic detection system drives the quadrature incremental encoder to rotate during the movement and outputs two quadrature pulse signals; The quadrature pulse signal is counted to obtain the displacement data of the system.

The invention installs the orthogonal incremental encoder on the moving roller of the detection system, the detection system moves forward through the rolling of the roller, and the rolling of the roller drives the orthogonal incremental encoder to rotate, thereby outputting two orthogonal pulse signals. Among them, the pulse signal corresponds to the rolling of the roller. By counting the pulse signal, the number of rolling circles of the roller can be obtained, thereby obtaining the displacement data of the detection system. According to the displacement data, the movement of the system can be controlled, and the broken wire of the entire PCCP pipeline can be realized. detection.

Optionally, the detection probe group responds to the primary field electromagnetic signal through the PCCP pipe wall and the process of generating a voltage signal through the secondary field electromagnetic signal induced by the pipe wall and the prestressed steel wire, including: the excitation coil of the excitation probe 1. The receiving coil of the detection probe and the hoop prestressed steel wire constitute a multi-stage electromagnetic coupling system; the primary field electromagnetic signal generated by the excitation probe penetrates the pipe wall of the PCCP pipe and acts on the prestress after propagating along the pipe axis outside the pipe. The steel wire generates a secondary field electromagnetic signal; the secondary field electromagnetic signal penetrates the pipe wall of the PCCP pipe again, and is coupled to the detection probe, thereby generating a voltage signal.

The invention adopts the far-field eddy current electromagnetic detection principle to monitor PCCP broken wires. The excitation coil of the excitation probe, the receiving coil of the detection probe and the circumferential prestressed steel wire form a multi-stage electromagnetic coupling system, wherein the prestressed steel wire is the secondary of the excitation coil. Coil, which is also the primary coil of the receiving coil. The excitation coil generates an alternating excitation magnetic field as the primary field, and the primary field penetrates the PCCP steel cylinder and acts on the prestressed steel wire to generate a mutual inductance alternating voltage/current to form a secondary field, which is then coupled to the receiving coil. When the prestressed steel wire is broken or severely corroded, the intensity and phase of the secondary field will be distorted, and the distorted signal will be coupled to the receiving coil, thereby realizing broken wire detection.

Optionally, the preset digital feature is pre-stored in the industrial computer, and the recognition result is determined by comparing the digital signal in the buffer with the preset digital feature.

The present invention pre-stores the digital features representing the PCCP pipeline interface to the industrial control computer, and the industrial control computer saves the signal to the buffer after receiving the digital signal and compares it with the digital feature. If the comparison results are consistent, the preset digital feature is recognized, representing At this time, the detection system completes the detection of the current PCCP pipe joint, saves all the digital signals of the current pipe joint to the local memory, and restarts the detection of the next pipe joint. The detection of broken wires of PCCP pipelines is divided into pipe sections, so that the general position of broken wires can be determined first according to different pipe sections, and the detection rate can be improved.

Optionally, the implementation process of the circumferential positioning includes: if the wire breakage occurs in the PCCP pipeline, the intensity of the secondary field electromagnetic signal induced by the primary field electromagnetic signal through the PCCP pipeline wall and the prestressed steel wire and phase distortion; based on the different relative positions of each of the detection probes and the place where the broken wire occurs, there is a difference in the voltage signal generated by the detection probe group based on the electromagnetic signal of the secondary field; according to the difference, the PCCP broken wire is carried out Circular positioning.

In the present invention, PCCP broken wires are located in the circular direction through a sending and receiving probe array, and the probes of the detection probe group are arranged at intervals along the pipeline ring direction. The relative position of the position is different, resulting in a difference in the induced voltage signal. Through this difference, the circumferential positioning of the PCCP broken wire can be realized, and the accuracy of the axial positioning can also be improved.

Optionally, the number, axial location and circumferential location of the PCCP broken wires are set to be judged during the PCCP pipeline inspection or after the PCCP pipeline inspection is completed.

The present invention can judge the position and number of broken wires during the detection process of the PCCP pipeline, and can also judge after all pipe joints are detected, so it can be applied to different application scenarios.

Optionally, the multi-channel receiver improves the signal-to-noise ratio of each channel through low-noise amplification and bi-phase correlation reception, and extracts a voltage signal of the same frequency as the AC signal transmitted by the transmitter.

In the detection process of the present invention, the primary field electromagnetic signal passes through the pipe wall of the PCCP pipe and the prestressed steel wire to induce the secondary field electromagnetic signal, and the secondary field electromagnetic signal penetrates the pipe wall of the PCCP pipe again to reach the detection probe group. The voltage signal generated by the induction of the far-field eddy current signal penetrating the pipe wall is particularly weak, so the multi-channel receiver improves the signal-to-noise ratio of each channel through low-noise amplification and bi-phase correlation reception, thereby extracting the AC transmitted by the transmitter The voltage signal with the same frequency as the signal can effectively overcome the influence of the system's inherent random noise on the single channel, and improve the accuracy of PCCP broken wire detection.

Description of drawings

In order to more clearly illustrate the specific implementation of the present invention or the technical solutions in the prior art, the following will briefly introduce the accompanying drawings that need to be used in the specific implementation or description of the prior art. Obviously, the accompanying drawings in the following description The drawings show some implementations of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

Fig. 1 is the structural representation of a kind of PCCP broken wire multi-channel electromagnetic detection system that the embodiment of the present invention provides;

Fig. 2 is the carrying platform schematic diagram of a kind of PCCP broken wire multi-channel electromagnetic detection system that the embodiment of the present invention provides;

Fig. 3 is a schematic diagram of a transceiver probe array of a PCCP broken wire multi-channel electromagnetic detection system provided by an embodiment of the present invention;

Fig. 4 is the schematic flow chart of a kind of PCCP broken wire multi-channel electromagnetic detection method provided by the embodiment of the present invention;

Fig. 5 is a schematic diagram of the principle of the far-field eddy current electromagnetic detection method of a PCCP broken wire multi-channel electromagnetic detection method provided by an embodiment of the present invention.

Reference signs:

1-leading cabin; 2-equipment cabin; 3-excitation probe; 4-detection probe group; 5-orthogonal incremental encoder; 6-support arm; 7-PCCP pipeline.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as there is no conflict with each other.

Example 1

The embodiment of the present invention provides a PCCP broken wire multi-channel electromagnetic detection system, as shown in Figure 1, the system includes: industrial control computer, transmitter, excitation probe, detection probe group, multi-channel receiver and orthogonal incremental encoding device;

The industrial computer is used to install detection software, send control instructions to the transmitter, receive the quadrature pulse signal of the quadrature incremental encoder to calculate displacement data, and receive the digital signal of the multi-channel receiver for identification and storage, and analyze and calculate according to the digital signal, and judge the number of PCCP broken wires, axial positioning and circumferential positioning;

The transmitter includes a signal generator and a driver, the signal generator is used to generate an AC signal according to the first control instruction, and the driver is used to drive the excitation probe based on the AC signal to generate a primary field electromagnetic signal;

The detection probe group is used to respond to the secondary field electromagnetic signal induced by the primary field electromagnetic signal through the pipe wall and prestressed steel wire of the PCCP pipeline, generate a voltage signal based on the secondary field electromagnetic signal and transmit it to the multi-channel receiver;

The multi-channel receiver performs digital processing on the received voltage signal and generates a digital signal.

Specifically, in the embodiment of the present invention, as shown in FIG. 2 , the carrying platform of the detection system is shown, and the detection probe set of the present invention includes 4 detection probes, but it is not limited thereto. Among them, the carrying platform is supported by nine supporting arms 6 with rolling wheels, and the nine supporting arms are respectively installed around the leading cabin 1 and the equipment cabin 2 of the carrying platform, and the industrial computer, transmitter, and multi-channel receiver are all installed in the In the equipment cabin 2 of the carrying platform, the orthogonal incremental encoder 5 is installed on the shaft of any one of the rolling wheels of the two support arms of the upper part of the leading cabin 1 of the carrying platform, and the excitation probe 3 and the detection probe group 4 The four detection probes are respectively installed on the support arms 6 around the equipment compartment 2 of the carrying platform, and each probe is parallel to the axial direction of the pipeline to be tested and evenly arranged along the circumferential direction of the PCCP pipeline, and is vertically arranged with the exciting probe space to form a Transmitting and receiving four received transceiver probe array, as shown in Figure 3.

In addition, the excitation probe is used as a sensor to convert the AC signal output by the low-frequency power amplifier into magnetic field energy and emit it, and induce eddy current signals on the PCCP tube wall. However, the far-field eddy current signal is very weak, at the millivolt or even microvolt level, and is difficult to extract. Therefore, the present invention uses a single-loop coil as the excitation coil of the excitation probe, but it is not limited thereto. In addition, setting the shielding disk on the excitation probe can attenuate the effect of direct coupling energy between the excitation probe and the detection probe group, and can reduce direct coupling interference during detection. The receiving coil of the detection probe also adopts the form of a single-loop coil to submit the receiving sensitivity.

The PCCP broken wire multi-channel electromagnetic detection system provided by the embodiment of the present invention controls the entire detection process through an industrial computer, including receiving the quadrature pulse signal of the quadrature incremental encoder to calculate the displacement data of the system, and controlling the transmitter during the system movement. Generate an AC signal and generate a primary field electromagnetic signal by stimulating the probe, and detect the probe group to respond to the primary field electromagnetic signal and generate a voltage signal through the secondary field electromagnetic signal induced by the PCCP pipe wall and prestressed steel wire, and the industrial control computer receives multi-channel The receiver digitally processes the voltage signal to obtain a digital signal, and judges the number of PCCP broken wires, axial positioning and circumferential positioning according to the digital signal. The invention conducts multi-channel electromagnetic detection on the PCCP pipeline through a sending and receiving probe array, has the functions of detecting the number of PCCP broken wires and positioning in the axial and circumferential directions, and can improve the detection accuracy of the broken wires of the PCCP pipeline.

Example 2

The embodiment of the present invention provides a multi-channel electromagnetic detection method for PCCP broken wires, as shown in Figure 4, the method is based on the system provided in Embodiment 1 to detect PCCP broken wires, and the steps include:

In step S1, the PCCP broken wire multi-channel electromagnetic detection system obtains displacement data through an orthogonal incremental encoder during the movement process, and excites the probe to generate a primary field electromagnetic signal according to the AC signal emitted by the transmitter.

Specifically, in the embodiment of the present invention, as shown in Figure 2, the carrying platform of the detection system can travel in the PCCP pipeline 7 under the control of manual push or electric traction, and when the roller of the support arm rolls along the pipe wall Drive the rotary shaft of the quadrature incremental encoder to rotate, so as to output two quadrature pulse signals. The pulse signal corresponds to the rolling of the roller, and the number of rolling circles of the roller can be obtained by counting the two pulse signals, thereby obtaining the displacement data of the carrying platform.

In the embodiment of the present invention, during the moving process of the carrying platform, the industrial computer sends a control instruction to the transmitter, and controls the signal generator of the transmitter to output an AC signal of a certain frequency and power. Among them, to meet the conditions of far-field eddy current detection, the AC signal must meet two conditions: one is to have sufficient penetration capability, and the other is to have sufficient power. The penetrating ability of the AC signal is mainly determined by the frequency, and the power depends on the later amplification. Therefore, the present invention uses a low-frequency sinusoidal signal, and after generating the AC signal, a low-frequency power amplifier is used to amplify the power of the sinusoidal signal. After receiving the amplified AC signal, the driver of the transmitter drives the excitation probe to continuously generate a low-frequency AC electromagnetic field, that is, the primary field electromagnetic signal.

Step S2: The detection probe group responds to the primary field electromagnetic signal and generates a voltage signal through the secondary field electromagnetic signal induced by the PCCP pipe wall and the prestressed steel wire.

Specifically, in the embodiment of the present invention, the excitation coil of the excitation probe, the receiving coil of the detection probe, and the hoop prestressed steel wire form a multi-stage electromagnetic coupling system, and the broken wire detection is carried out by using the principle of far-field eddy current electromagnetic detection. The principle is shown in Figure 5 shown. The primary field electromagnetic signal generated by the excitation probe penetrates the pipe wall of the PCCP pipe and acts on the prestressed steel wire after propagating outside the pipe along the pipe axis to generate a secondary field electromagnetic signal. The secondary field electromagnetic signal penetrates the pipe wall of the PCCP pipe again. The wall is coupled to the detection probe set, and the detection probe set induces a voltage signal.

Step S3: The multi-channel receiver generates a digital signal by digitizing the received voltage signal, and sends the digital signal to an industrial computer.

Specifically, in the embodiment of the present invention, after the multi-channel receiver receives the voltage signal of the detection probe group, the signal-to-noise ratio of each channel is improved through low-noise amplification and bi-phase correlation reception, and the AC signal transmitted by the transmitter As a reference signal, a weak voltage signal with the same frequency as the reference signal is extracted through parameter adjustment. After digitizing the voltage signal, the digital signal is obtained and sent to the industrial control computer.

Step S4: The industrial control computer stores the received digital signal into the buffer, and identifies the digital signal. If the preset digital feature at the PCCP pipe interface is not recognized, repeat S1-S3. If the digital signal is recognized If the preset digital feature is used, the digital signal in the buffer is stored in a local memory.

Specifically, in the embodiment of the present invention, the detection process is distinguished according to different joints of the PCCP pipeline, and interfaces of different joints of the PCCP pipeline are represented by preset digital features. After receiving the digital signal, the industrial control computer stores it in the buffer first, and compares it with the preset digital feature stored in the industrial control computer. If the comparison is successful, the preset digital feature is recognized, which means that the detection system has completed the current PCCP at this time. For the detection of pipe joints, all the digital signals of the current pipe joints are uniformly saved to the local memory, and the detection of the next pipe joint is restarted. If the comparison is unsuccessful, the carrier platform continues to move forward, and the obtained digital signal record is stored in the buffer area until the digital feature is recognized.

Step S5: Repeat S1-S4 according to the displacement data until the detection of all pipe joints of the PCCP pipeline is completed, and judge the number of PCCP broken wires, axial positioning and circumferential positioning according to the detection results.

Specifically, in the embodiment of the present invention, the current displacement data of the carrier platform is obtained according to the orthogonal incremental encoder, and it is judged according to the displacement data whether the detection of all the pipe joints of the PCCP pipeline is completed. According to the detection results, the number of PCCP broken wires, axial positioning and circumferential positioning can be judged. In the embodiment of the present invention, the position and number of broken wires can be judged during the detection process of PCCP pipelines, and can also be carried out after the detection of all pipe joints is completed. judge.

In the embodiment of the present invention, if the PCCP pipeline breaks, the intensity and phase of the secondary field electromagnetic signal induced by the primary field electromagnetic signal passing through the PCCP pipeline wall and the prestressed steel wire will be distorted. Since the relative positions of each detection probe and the place where the broken wire occurs are different, the voltage signals generated by the detection probe group based on the electromagnetic signal of the secondary field are also different. At this time, the position-intensity curve, position-phase curve and angle- Strength curve, through the quantitative analysis of the curve, the number of broken wires, longitudinal positioning and circumferential positioning can be obtained.

In the PCCP broken wire multi-channel electromagnetic detection method provided by the embodiment of the present invention, the primary field electromagnetic signal is generated by the excitation probe according to the AC signal of the transmitter, and the detection probe group responds to the primary field electromagnetic signal through the pipe wall of the PCCP pipeline and the prestressed steel wire. The secondary field electromagnetic signal and generate a voltage signal, the multi-channel receiver receives the voltage signal and digitizes it, then sends the obtained digital signal to the industrial control computer, the industrial control computer identifies and stores the digital signal, and through the orthogonal incremental encoding The device realizes the detection of all pipe joints, and judges the number of PCCP broken wires, axial positioning and circumferential positioning according to the detection results. The invention conducts multi-channel electromagnetic detection on the PCCP pipeline through a sending and receiving probe array, has the functions of detecting the number of PCCP broken wires and positioning in the axial and circumferential directions, and can improve the detection accuracy of the broken wires of the PCCP pipeline.

Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall into the scope of the appended claims. within the limited range.

Claims (10)

1. A PCCP wire break multichannel electromagnetic detection system, comprising: the system comprises an industrial control computer, a transmitter, an excitation probe, a detection probe group, a multichannel receiver and an orthogonal incremental encoder;

the industrial control computer is used for installing detection software, receiving the orthogonal pulse signals of the orthogonal incremental encoder, calculating displacement data, sending control instructions to the transmitter, receiving digital signals of the multichannel receiver, identifying and storing the digital signals, and judging the number, axial positioning and circumferential positioning of PCCP broken wires according to the digital signals;

the transmitter comprises a signal generator and a driver, wherein the signal generator is used for generating an alternating current signal according to the control instruction, and the driver is used for driving the excitation probe to generate a primary field electromagnetic signal based on the alternating current signal;

the detection probe group is used for responding to the primary field electromagnetic signals, generating voltage signals based on the secondary field electromagnetic signals and transmitting the voltage signals to the multichannel receiver through the pipe wall of the PCCP pipe and the secondary field electromagnetic signals induced by the prestressed steel wire;

the multichannel receiver digitizes the received voltage signal and generates a digital signal.

2. The PCCP yarn break multichannel electromagnetic detection system of claim 1, wherein the detection probe set comprises: and the detection probes are parallel to the axis direction of the detected pipeline, are uniformly arranged along the circumferential direction of the PCCP pipeline, and are arranged in a space perpendicular to the excitation probes.

3. A PCCP yarn breakage multi-channel electromagnetic detection method, characterized in that yarn breakage detection is performed based on the PCCP yarn breakage multi-channel electromagnetic detection system according to claims 1-2, the detection method comprising:

s1: the PCCP wire-breaking multichannel electromagnetic detection system acquires displacement data through an orthogonal incremental encoder in the moving process, and an excitation probe generates a primary field electromagnetic signal according to an alternating current signal transmitted by a transmitter;

s2: the detection probe group responds to the primary field electromagnetic signals, and generates voltage signals through secondary field electromagnetic signals induced by the pipe wall of the PCCP pipe and the prestressed steel wire;

s3: the multichannel receiver generates a digital signal by performing digital processing on the received voltage signal and sends the digital signal to an industrial control computer;

s4: the industrial control computer stores the received digital signals into a buffer zone, identifies the digital signals, repeats S1-S3 if the preset digital characteristics at the PCCP pipeline interface are not identified, and stores the digital signals in the buffer zone into a local memory if the preset digital characteristics are identified;

s5: and repeating S1-S4 according to the displacement data until the detection of all pipe joints of the PCCP pipeline is completed, and judging the number of PCCP broken wires, axial positioning and circumferential positioning according to the detection result.

4. The PCCP wire-break multichannel electromagnetic detection method of claim 3, wherein the detection system performs wire-break multichannel electromagnetic detection by moving in a PCCP pipe.

5. The PCCP yarn breakage multi-channel electromagnetic testing method according to claim 3, wherein the process of acquiring displacement data includes:

the PCCP wire breakage multichannel electromagnetic detection system drives the orthogonal incremental encoder to rotate and outputs two paths of orthogonal pulse signals in the moving process;

and acquiring displacement data of the system by counting the orthogonal pulse signals.

6. The PCCP yarn break multichannel electromagnetic testing method of claim 3, wherein the process of the testing probe set responding to the primary field electromagnetic signal and generating a voltage signal through the secondary field electromagnetic signal induced by the wall of the PCCP pipe and the prestressed wire comprises:

the exciting coil of the exciting probe, the receiving coil of the detecting probe and the circumferential prestress steel wire form a multistage electromagnetic coupling system;

the primary field electromagnetic signal generated by the excitation probe penetrates through the pipe wall of the PCCP pipe and acts on the prestressed wire after axially propagating along the pipe outside the pipe to generate a secondary field electromagnetic signal;

the secondary field electromagnetic signal penetrates again through the wall of the PCCP pipe and is coupled to the detection probe set, thereby generating a voltage signal.

7. The PCCP yarn breakage multi-channel electromagnetic detection method according to claim 3, wherein the preset digital characteristic is stored in the industrial control computer in advance, and the recognition result is determined by comparing the digital signal of the buffer area with the preset digital characteristic.

8. The PCCP yarn breakage multichannel electromagnetic detection method according to claim 3, wherein the implementation process of the circumferential positioning includes:

if the PCCP pipeline is broken, the intensity and the phase of the secondary field electromagnetic signal which is induced by the primary field electromagnetic signal through the pipe wall of the PCCP pipeline and the prestressed steel wire are distorted;

based on different relative positions of the detection probes and the broken wire, the voltage signals generated by the detection probe group based on the secondary field electromagnetic signals are different;

and carrying out circumferential positioning on the PCCP broken wire by adopting a software algorithm according to the difference.

9. The PCCP yarn break multichannel electromagnetic detection method according to claim 3, wherein the number, axial positioning and circumferential positioning of the PCCP yarn breaks are set to be determined during PCCP pipe detection or after PCCP pipe detection is completed.

10. The PCCP yarn break multi-channel electromagnetic detection method of claim 3, wherein the multi-channel receiver increases signal-to-noise ratio of each channel through low noise amplification and dual-phase correlation reception, and extracts a voltage signal of the same frequency as the ac signal transmitted by the transmitter.

Images