CN103412038B - The portable ACFM detector of a kind of Based PC/104 embedded system - Google Patents
The portable ACFM detector of a kind of Based PC/104 embedded system Download PDFInfo
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Abstract
The invention discloses the portable ACFM detector of a kind of Based PC/104 embedded system, comprise the signal generating module that pumping signal occurs, the probe detecting surface of the work, simulating signal carried out pretreated Signal-regulated kinase, for each unit electricity consumption of instrument power module, data store and transport module, micro controller module, A/D acquisition module simulating signal being carried out to data acquisition and display module that digital signal is processed.The present invention can carry out non-contact detecting to the various surface imperfection of hardware, carry out polishing or decontamination without the need to effects on surface during detection, can directly penetrate anticorrosive coat to detect, along with whether the scanning real-time judgment defect of probe exists, draws magnetic induction density curve and butterfly diagram.The present invention has merged the technology such as electronic circuit, virtual instrument, embedded Control, digital signal processing and electromagnetic sensor in one, and portable construction is easy to operate, favourable safety detection and the assess effectiveness that improve petrochemical equipment.
Description
Technical field
The invention belongs to detector technical field, particularly relate to the portable ACFM detector of a kind of Based PC/104 embedded system.
Background technology
Along with petroleum exploration and development dynamics strengthen, the working environment of petroleum equipment is more and more severe, directly causes failure accidents also to increase, the safe reliability of petroleum equipment thereupon, has nowadays become the focus that society is paid close attention to.In sum, the safety problem of petroleum industry is outstanding day by day, and the performance of current industrial environment to nondestructive detecting instrument is had higher requirement.Non-Destructive Testing is the requisite effective tool of industrial development, and reflect a national Industry Development Level to a certain extent, its importance gains public acceptance.
Alternating current field measurement (Al ternat ing Current Fie ld Measurement), no matter for pressure vessel or ocean platform steel construction, has the reliability of application and certain limit in large quantities.For ensureing the safe operation of petroleum industry equipment, realizing rapid and convenient and detecting, providing table of equipment planar defect reliable testing result, minimizing accident ground occurs, nowadays in the urgent need to a set of portable ACFM detector.
Summary of the invention
The object of the present invention is to provide one not only rational in infrastructure but also have and enrich human-computer interaction function, the portable ACFM detector of low cost, high efficiency Based PC/104.
The embodiment of the present invention realizes like this, the portable ACFM detector of a kind of Based PC/104 embedded system, comprise the signal generating module that pumping signal occurs, the probe detecting surface of the work, simulating signal carried out pretreated Signal-regulated kinase, for each unit electricity consumption of instrument power module, data store and transport module, micro controller module 6, A/D acquisition module simulating signal being carried out to data acquisition and display module that digital signal is processed;
For the power module of each unit electricity consumption of instrument, provide power supply to the unit of instrument, be connected respectively with signal generating module, Signal-regulated kinase 3 and micro controller module;
There is the signal generating module of pumping signal, i.e. signal driving source, the function generator that signal generating circuit comprises and emitter follower, the excitation source signal produced is the sine wave signal of frequency 6kHz, be connected with the probe detecting surface of the work, be connected with power module simultaneously;
Detect the probe of surface of the work, comprise drive coil and magnetic test coil, and pretreated Signal-regulated kinase is carried out to simulating signal be connected;
Pretreated Signal-regulated kinase is carried out to simulating signal, the enlarge leadingly part of its signal conditioning circuit adopts two-stage to amplify, first order amplification is realized by instrument amplifier, second level amplifying circuit adopts and builds single order in-phase amplifier by operational amplifier, and the filtering part of signal conditioning circuit selects low-pass filter.For the pre-service unitized to simulating signal, be interconnected with A/D acquisition module simulating signal being carried out to data acquisition, be connected with power module simultaneously;
Simulating signal is carried out to the A/D acquisition module of data acquisition, application controls bus standard gathers, and for carrying out data acquisition to simulating signal, is interconnected the micro controller module that digital signal processes;
To the micro controller module that digital signal processes, mainly comprise mainboard, mainly digital signal is processed, stored by SATA interface and data and be interconnected with transport module, be interconnected with display module simultaneously;
Data store and transport module, and main realization is to the storage of data and transmission;
Display module, adopts LCD touch screen, is interconnected with micro controller module.
Further, pop one's head in and to be made up of exciting unit and detecting unit.Exciting unit is made up of U-shaped manganese-zinc ferrite magnetic core and the enameled wire that is wrapped in 0.15mm in the middle part of U-shaped magnetic core, and detecting unit is made up of the enameled wire of the 0.05mm of rectangular shaped core and two groups of orthogonal winding magnetic cores.Detecting unit is positioned at the middle and lower part of exciting unit, and detecting unit diameter is less than exciting unit.
Further, the alternating message source Vi minus earth of single order in-phase amplifier, positive pole accesses the in-phase end of amplifier LM324 by resistance RL, an end of oppisite phase part of amplifier LM324 is by resistance R1 ground connection, a part accesses the output terminal of amplifier LM324 by resistance RF simultaneously, the pin 4 of amplifier LM324 meets high level VCC, and 11 pins of amplifier LM324 meet low level VEE.
Further, preset ARTIFICIAL CRACK steel plate utilizes the portable ACFM detector of Based PC/104 to detect mild-steel sheet surface long 40mm, wide 1mm, the crackle of dark 8mm, and workpiece is mild carbon steel; The prefabricated artificial defect in surface adopts electric spark method to process, and the profile of artificial defect is half elliptic crack defect; In test specimen, the degree of depth of crackle is respectively 5mm, 2mm, 8mm.
The portable ACFM detector that the present invention is based on PC/104 can carry out non-contact detecting to the various surface imperfection of hardware, carry out polishing or decontamination without the need to effects on surface during detection, along with whether the scanning real-time judgment defect of probe exists, draws magnetic induction density curve and butterfly diagram.
The portable ACFM detector detection sensitivity that the present invention is based on PC/104 is high and simple to operate, applicable testing staff is convenient for carrying, and software intelligent level is high, less demanding to testing staff's operant level, this instrument is applicable to oil field working environment, has practical value.
Accompanying drawing explanation
The portable ACFM detector schematic diagram of Based PC/104 that Fig. 1 embodiment of the present invention provides;
Fig. 2 is the structural drawing of the probe that the embodiment of the present invention provides;
The single order in-phase amplification circuit figure that Fig. 3 embodiment of the present invention provides;
The structural representation of the preset ARTIFICIAL CRACK steel plate that Fig. 4 embodiment of the present invention provides;
The Bz direction magnetic field intensity amplitude test curve figure that Fig. 5 embodiment of the present invention provides;
The Bx direction magnetic field intensity amplitude test curve figure that Fig. 6 embodiment of the present invention provides.
Embodiment
In order to make object of the present invention, technical scheme and advantage clearly understand, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the present invention, be not intended to limit the present invention.
The invention discloses a kind of portable ACFM (Alternating Current FieldMeasurement) detector of Based PC/104.Detecting instrument is mainly divided into hardware components and software section, hardware components mainly realizes system power supply, signal generation, signal condition, signals collecting and result Presentation Function, software section realizes signals collecting, process and human-computer interaction function, according to the testing result judgment device material continuity of Magnetic field strength curve and butterfly diagram.
Fig. 1 is the portable ACFM detector schematic diagram of Based PC/104.It comprises the signal generating module 1 that pumping signal occurs, the probe 2 detecting surface of the work, simulating signal carried out pretreated Signal-regulated kinase 3, for each unit electricity consumption of instrument power module 4, data store and transport module 5, micro controller module 6, the A/D acquisition module 7 simulating signal being carried out to data acquisition and display module 8 that digital signal is processed.
For the power module 4 of each unit electricity consumption of instrument, provide power supply to the unit of instrument.Be connected respectively with signal generating module 1, Signal-regulated kinase 3 and micro controller module 6;
There is the signal generating module 1 of pumping signal, i.e. signal driving source, the function generator ICL8038 that signal generating circuit comprises and emitter follower, the excitation source signal produced is the sine wave signal of frequency 6kHz, be connected with the probe 2 detecting surface of the work, be connected with power module 4 simultaneously;
Detect the probe 2 of surface of the work, comprise drive coil and magnetic test coil, and simulating signal is carried out to pretreated Signal-regulated kinase 3 and be connected;
Pretreated Signal-regulated kinase 3 is carried out to simulating signal, the enlarge leadingly part of its signal conditioning circuit adopts two-stage to amplify, first order amplification is realized by instrument amplifier AD620, second level amplifying circuit adopts and builds single order in-phase amplifier by operational amplifier, and the filtering part of signal conditioning circuit selects low-pass filter.For the pre-service unitized to simulating signal, be interconnected with the A/D acquisition module 7 simulating signal being carried out to data acquisition, be connected with power module 4 simultaneously;
Simulating signal is carried out to the A/D acquisition module 7 of data acquisition, application PC/104 control bus standard acquisition, for carrying out data acquisition to simulating signal, is interconnected the micro controller module 6 that digital signal processes;
To the micro controller module 6 that digital signal processes, mainly comprise PC/104 mainboard, mainly digital signal is processed, stored by SATA interface and data and be interconnected with transport module 5, be interconnected with display module 8 simultaneously;
Data store and transport module 5, mainly realize being stored in transmission to data;
Display module 8, adopts LCD touch screen, is interconnected with micro controller module 6.
Fig. 2 is the structural drawing of the probe detecting surface of the work.Probe 2 is made up of exciting unit and detecting unit.Exciting unit is made up of U-shaped manganese-zinc ferrite magnetic core and the enameled wire that is wrapped in 0.15mm in the middle part of U-shaped magnetic core, and detecting unit is made up of the enameled wire of the 0.05mm of rectangular shaped core and two groups of orthogonal winding magnetic cores.Detecting unit is positioned at the middle and lower part of exciting unit, and detecting unit diameter is less than exciting unit.
Fig. 3 is the circuit diagram of single order in-phase amplifier.Alternating message source Vi minus earth, positive pole accesses the in-phase end 3 of amplifier LM324 by resistance RL, end of oppisite phase 2 part of amplifier LM324 is by resistance R1 ground connection, a part accesses the output terminal 1 of amplifier LM324 by resistance RF simultaneously, 4 pins of amplifier LM324 meet high level VCC, and 11 pins of amplifier LM324 meet low level VEE.
Fig. 4 is the structural representation of preset ARTIFICIAL CRACK steel plate.Utilize the portable ACFM detector of Based PC/104 to detect mild-steel sheet surface long 40mm, wide 1mm, the crackle of dark 8mm, workpiece is mild carbon steel.The prefabricated artificial defect in surface adopts electric spark method to process, and the profile of artificial defect is half elliptic crack defect.In test specimen, the degree of depth of crackle 1,2,3 is respectively 5mm, 2mm, 8mm.
Three, principle of work
The portable ACFM detector course of work of Based PC/104: open power switch device, enter and design ACFM inspection software interface under LabVIEW environment, mouse function is realized by touch-screen, optimum configurations is carried out by industrial keyboard, the pumping signal that signal generating circuit 1 produces is to the exciting unit of probe 2, probe 2 is placed in surface of the work, the exciting unit of probe 2 is at surface of the work excitation uniform induction electric current, from faraday electromagnetic induction principle, surface of the work produces transient state uniform induction magnetic field immediately, the detecting unit picking up work piece surface induction strength component of probe 2, represent magnetic induction density in the form of voltage, form detection signal, single incentive probe detection signal is two-way, comprise Bx direction and Bz direction, it carries out amplification by signal conditioning circuit 3 and filtering realizes the preposition pre-service of simulating signal, introduce original excitation signal as reference signal, PC/104 acquisition module 7 gathers two-way detection signal and a road reference signal, capture card carries A/D converter, PC/104 mainboard 6 is imported into by PC/104 bus after signal carries out A/D conversion, PC/104 mainboard 6 pairs of detection signals carry out high-speed data process, signal digital filtering is realized by the ACFM inspection software of exploitation, correlation analysis, magnetic field amplitude curve and butterfly diagram are drawn, shown in real time by lcd screen 8 pairs of surface of the work magnetic field amplitude curves and butterfly diagram, data store and store in transport module 5 and detect data, by detecting analysis software display testing result, can judge Surface Flaw.
Determining defects.If there is crackle in surface of the work, current signal can produce disturbance at crackle two ends, namely transient state magnetic distorted signal is produced, according to probe 2 pick up detection signal after acquisition and processing, real-time rendering goes out magnetic density curve and butterfly diagram, can judge defective locations and size by Bx, Bz magnetic field intensity amplitude curve and butterfly diagram.Bz signal reaches peak value at crackle two ends, and minimum value appears in Bx signal in crackle bosom, and as shown in Figure 2 and Figure 6, can be easy to position and the scope of quantitative test defect, this instrument can realize quantitative detection.
ACFM inspection software is characterized in that, can carry out initial parameter setting, real-time rendering Magnetic field strength curve, real-time rendering phase tranformation curve and butterfly diagram, and can according to testing result judgment device damage location.Initiation parameter arranges to comprise and arranges number of channels, initial passage, frequency acquisition and collection and count, wavelet packet analysis and cross-correlation analysis is adopted to carry out digital signal processing to alternating current field measurement signal, realize carrying out phase sensitive detection and low-pass filtering to detection signal, utilize the relevant function method of cross-spectral density to carry out phase-detection, and can carry out transmit to detection data and preserve and operate.
The feature of the portable ACFM detector of Based PC/104 is, kernal hardware configuration design adopts the framework of PC/104 mainboard+PC/104 collection plate.The detection signal of pickup, after signal conditioning circuit 3, imports PC/104 acquisition module 7 into, and simulating signal, after A/D conversion, is imported PC/104 mainboard 6 into by PC104 bus, realized Signal acquiring and processing task.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, all any amendments done within the spirit and principles in the present invention, equivalent replacement and improvement etc., all should be included within protection scope of the present invention.
Claims (1)
1. the portable ACFM detector of Based PC/104 embedded system, it is characterized in that, comprise the signal generating module that pumping signal occurs, the probe detecting surface of the work, simulating signal carried out pretreated Signal-regulated kinase, for each unit electricity consumption of instrument power module, data store and transport module, micro controller module, A/D acquisition module simulating signal being carried out to data acquisition and display module that digital signal is processed;
For the power module of each unit electricity consumption of instrument, for providing power supply to the unit of instrument, be connected respectively with signal generating module, Signal-regulated kinase and micro controller module;
The signal generating module of pumping signal occurs, i.e. signal driving source, the function generator that signal generating circuit comprises is connected with the probe of emitter follower with detection surface of the work, is connected with power module simultaneously;
Detect the probe of surface of the work, comprise drive coil and magnetic test coil, and pretreated Signal-regulated kinase is carried out to simulating signal be connected;
Pretreated Signal-regulated kinase is carried out to simulating signal, the enlarge leadingly part of its signal conditioning circuit adopts two-stage to amplify, first order amplification is realized by instrument amplifier, second level amplifying circuit adopts and builds single order in-phase amplifier by operational amplifier, and the filtering part of signal conditioning circuit selects low-pass filter; For the pre-service unitized to simulating signal, be interconnected with A/D acquisition module simulating signal being carried out to data acquisition, be connected with power module simultaneously;
Simulating signal is carried out to the A/D acquisition module of data acquisition, application controls bus standard gathers, and for carrying out data acquisition to simulating signal, is interconnected the micro controller module that digital signal processes; To the micro controller module that digital signal processes, mainly comprise mainboard, for processing digital signal, being stored by SATA interface and data and being interconnected with transport module, being interconnected with display module simultaneously;
Data store and transport module, for the storage of data and transmission;
Display module, adopts LCD touch screen, is interconnected with micro controller module;
Described probe is made up of exciting unit and detecting unit; Exciting unit is made up of U-shaped manganese-zinc ferrite magnetic core and the enameled wire that is wrapped in 0.15mm in the middle part of U-shaped magnetic core, and detecting unit is made up of the enameled wire of the 0.05mm of rectangular shaped core and two groups of orthogonal winding magnetic cores; Detecting unit is positioned at the middle and lower part of exciting unit, and detecting unit diameter is less than exciting unit;
The alternating message source Vi minus earth of described single order in-phase amplifier, positive pole accesses the in-phase end of amplifier LM324 by resistance RL, an end of oppisite phase part of amplifier LM324 is by resistance R1 ground connection, a part accesses the output terminal of amplifier LM324 by resistance RF simultaneously, the pin 4 of amplifier LM324 meets high level VCC, and 11 pins of amplifier LM324 meet low level VEE.
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| CN104049031B (en) * | 2014-06-12 | 2016-02-24 | 中国石油大学(华东) | A kind of subsurface defect pick-up unit based on ac magnetic field and detection method |
| CN104792858A (en) * | 2015-04-30 | 2015-07-22 | 南昌航空大学 | Alternating current electromagnetic field detector |
| CN106168601B (en) * | 2016-09-18 | 2018-07-03 | 中国石油大学(华东) | A kind of general AC electromagnetic field detection instrument of Multi probe compatibility |
| CN106248782B (en) * | 2016-09-18 | 2019-08-23 | 中国石油大学(华东) | A kind of deep-sea intelligent storage alternating current field measurement system and method for determining defects |
| CN106198719B (en) * | 2016-09-18 | 2018-06-22 | 中国石油大学(华东) | A kind of underwater conducting material structure object defect alternating current field measurement instrument |
| CN106371367B (en) * | 2016-10-13 | 2018-03-02 | 中国船舶工业系统工程研究院 | A kind of marine geophysical prospecting streamer data controller based on SATA interface |
| CN108918655A (en) * | 2018-08-09 | 2018-11-30 | 西红柿科技（武汉）有限公司 | A kind of storage tank bottom plate welding seam detector and system |
| CN110220967B (en) * | 2019-06-03 | 2022-12-23 | 南京航空航天大学 | Automatic identification method for cluster crack surface profile by ACFM technology |
| CN113607915B (en) * | 2021-04-23 | 2024-02-02 | 重庆工商大学 | Portable compost maturity detector and detection method based on embedded system |
| CN113390955B (en) * | 2021-07-08 | 2022-04-19 | 中国石油大学(华东) | Visual monitoring and evaluation method for cracks of alternating current magnetic field |
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