CN203148900U - Self-adaptive sensor for detecting grounding grid round steel bar corrosion - Google Patents
Self-adaptive sensor for detecting grounding grid round steel bar corrosion Download PDFInfo
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- CN203148900U CN203148900U CN 201220721960 CN201220721960U CN203148900U CN 203148900 U CN203148900 U CN 203148900U CN 201220721960 CN201220721960 CN 201220721960 CN 201220721960 U CN201220721960 U CN 201220721960U CN 203148900 U CN203148900 U CN 203148900U
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- slide block
- round steel
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Abstract
The utility model discloses a self-adaptive sensor for detecting grounding grid round steel bar corrosion, belongs to the field of nondestructive detection and particularly relates to a special ultrasonic guided-wave sensor for detecting grounding grid round steel bar corrosion of a power system by using ultrasonic guided-waves. The sensor is composed of 8-16 sensor units, wherein each sensor unit comprises a sensor shell (1), a slide block (3) embedded inside the sensor shell (1), a pair of springs (2) arranged between the sensor shell (1) and the slide block (3), a pair of locating pins (4) for locating the slide block, a piezoelectric plate (6), a protective layer (7) for supporting and protecting the piezoelectric plate (6), leading wires at the positive and negative poles of the piezoelectric plate and a shaft pin (8) for connecting the plurality of sensor units. In the actual use process, the sensor is composed of the 8-16 sensor units, and a loading way that sensors are uniformly distributed along the periphery of the side of a round steel bar is realized; and the sensor is suitable for the nondestructive detection of a general-specification grounding grid steel bar with the diameter of 14-28mm.
Description
Technical field
The corrosion of grounded screen round steel bar detects self-adapted sensor, belongs to the Non-Destructive Testing field, is specifically related to a kind of special-purpose supersonic guide-wave sensor that utilizes the corrosion of ultrasonic guided wave detecting electric system grounded screen round steel bar.
Background technology
Grounding net of transformer substation is the critical facility that ensures the power system security reliability service, and it not only provides a public reference potential for various electrical equipments in the transformer station, and fault current can also be drained rapidly when breaking down in system.Grounding net of transformer substation adopts grid type usually, and the grounded screen material therefor that China lays is mainly zinc-plated round steel bar or zinc-coated flat steel sheet bar, and mesh spacing is generally 6-12m, and buried depth is about 0.6-0.8m, and area is generally the floor area of transformer station.The grounded screen conductor life-span is about 8-10.
Because it is underground that the grounded screen conductor is embedded in, often because causing the grounded screen conductor resistance to change, corrosion breaks down a little.Break down if meet electric system, directly jeopardize the safe operation of electric system.The accident that the electric system that fracture causes takes place because of ground net corrosion happens occasionally, and a lot of accidents have all been brought enormous economic loss.Therefore, ground connection Device Testing and maintenance are seemed important and urgent.
The article that the Zhang Penghe of the Central China University of Science and Technology delivers at " robotization and instrument and meter " " grounding net defect Studies on Diagnosis summary " is summarized present grounded screen diagnostic method and is mainly comprised big amperometry, grounded screen nodal analysis, electromagnetic field analysis method, electrochemical methods and lossless detection method etc.
Big amperometry belongs to large-scale grounding network conventional sense content.China's " power equipment preventive trial rules " requirement was tackled the grounded screen of 110kV and above transformer station in per 2～3 years and is carried out a test, and test method adopts big current method exactly.Utilize big current method that earth mat is carried out complete detection and have a lot of difficulties, mainly contain: need to have a power failure and big current source, therefore the surveying work complexity implements bigger difficulty.
There are a lot of research institutions that the grounded screen nodal analysis is studied.Zhang Xiaoling publish an article in " High-Voltage Technology " " optimisation technique send out, substation ground net Application in Fault Diagnosis " adopt the parameter method of identification, utilize the node analysis method of circuit network theory, the associate(d) matrix theory, set up the sensitivity matrix diagnostic equation, satisfy the minimum branch road resistance of whole grounded screen energy consumption by asking for, reach the purpose of ground net corrosion fault diagnosis.The old first high post of University Of Chongqing, Liu Yugen publish an article at " University Of Chongqing's journal " " diagnostic method of grounded screen conductor state " fault diagnosis principle, network theory, matrix theory and computerized algorithm are combined, be applied to ground net corrosion diagnosis.Though these methods can reach the digging-free inspection to grounded screen fault, but bad for the real-time that grounded screen fault detects, need the professional according to first image data in the monitoring, adjust the node of measuring in real time, take multiple measurements, the popularization of this measuring method is restricted.
The article " Diagnosis ofbreaks in substations grounding grid by using the electromagnetic method " that scholars such as Michaloudaki in 2005 deliver at " Magnetics " detects the fracture position of grounded screen conductor by the method for electromagnetic field, but can not determine its extent of corrosion for the grounded screen of not fracture.North China Electric Power University has also carried out the research of this respect, carries out grounded screen fracture diagnosis by measuring the ground potential difference.Electromagnetic field measurements is subjected to the environmental interference noise effect big on the one hand, and its changes of magnetic field is very little when local corrosion appears in the grounded screen conductor of fenestral fabric on the other hand, and the feasible etch state that utilizes this diagnostic method to analyze conductor is very difficult.
Detection has launched research to the Yang Tao of Hunan University in 2011 to the grounded screen corrosion electrochemistry in his Master's thesis " ground net corrosion state-detection and life prediction thereof ", and the intelligent checking system of development can be grounded the corrosion of equipment situation to a certain extent and measure and life prediction.North China Electric Power Research Institute has developed ground net corrosion electrochemical in-situ detection system can measure electrochemical parameters such as the polarization resistance of grounded screen metal, electric resistance of soil.Electrochemical analysis method is ripe relatively by contrast, but electrochemical analysis method can only obtain the local corrosion data, and this method of soil environment areas with complicated is used difficulty.
He Ming in 2010 etc. have proposed a kind of anchor pole Non-Destructive Testing new method based on the magnetic striction wave guide principle in " application of magnetic striction wave guide in anchor pole detects ".In having studied anchor pole, on the longitudinal mode guided wave model based, calculate the dispersion curve of the anchor pole of diameter 20mm, built anchor pole test experience system, and utilized this system to finish in the air and the test experience of rock-bolt length and defective in the buried structure.The Liu Yang of Zhejiang University in 2010 in paper " magnetic striction wave guide anchor pole Non-Destructive Testing experimental study ", utilize the magnetic striction wave guide technology to guided wave the propagation in anchor pole carried out theoretical modeling.Proposed contactless guided wave excitation and method of reseptance, developed relevant experimental provision, and detection signal is handled and analyzed.Experimental result shows that the magnetic striction wave guide technology can be measured rock-bolt length and defective effectively reliably.But supersonic guide-wave is decayed very serious in being embedded in underground grounded screen round steel bar, the guided wave energy that the magnetostriction mode encourages a little less than, detect for the long grounded screen round steel bar of spacing 6-12 rice and to be difficult to realize.In addition, magneto strictive sensor need be wrapped in coil the round steel bar surface, and Design of Sensor is a very big problem, does not also have solution preferably at present.
The M.D.Beard of Imperial College " International Journal of Rock Mechanicsand Mining Sciences " publish an article " Non-destructive testingof rock boltsusing guided ultrasonic waves " studied the decay dispersion curve in the diameter 21.7mm anchor pole, obtained each mode decay minimum frequency, also utilize the high frequency guided wave to detect the anchor pole necking down in the paper, receive quite good detecting effectiveness.The glad grade of the Sun Ya of Beijing University of Technology has been applied for the patent of invention of " utilizing the supersonic guide-wave Non-Destructive Testing to be embedded in the method for rock-bolt length in the different medium ", has realized use ultrasonic guided wave detecting rock-bolt length.Xinan Science and Technology Univ.'s environment and Lee of resource institute equality excite the optimum of supersonic guide-wave in the free bolt has carried out theoretical analysis and experimental study, and drawing the best test waves frequency range of free bolt is the conclusion of 40-50kHz.It is emphasized that anchor pole has exposed termination, can realize that therefore sensor is installed in the end and the excitation guided wave.The grounded screen round steel bar does not then supply the termination of placement sensor, and the mode of end load is infeasible.
Grounded screen conductor material structure is the pole type, is reticulate texture after being welded to connect, and is embedded in electric power facility subsurfaces such as transformer station, is subjected to corrosive attack for a long time.Still nobody encourages the corrosion of ultrasound examination grounded screen conductor to carry out correlative study to piezoelectric sensor both at home and abroad at present.The corrosion of grounded screen round steel bar detects self-adapted sensor and can realize also effectively motivating supersonic guide-wave from grounded screen round steel bar side sensor installation, makes the detection of grounded screen round steel bar corrosion be achieved.
Summary of the invention
The purpose of this utility model provides a kind of grounded screen round steel bar corrosion that can practical application and detects self-adapted sensor, this sensor can be realized from the installation of round steel bar side and effectively motivate supersonic guide-wave, the grounded screen round steel bar is carried out corrosion default to be detected, obtain position and the extent of corrosion of corrosion default, be grounded effective detection of net round steel bar corrosion.
The utility model is to solve the problems of the technologies described above the technical scheme that adopts to be:
The corrosion of grounded screen round steel bar detects self-adapted sensor, it is characterized in that: it is by the pivot pin 8 hinged annulars of forming by a plurality of sensor units, wherein each sensor unit comprise sensor unit shell 1, slide block 3, piezoelectric patches 6, from the lead-in wire 5 that piezoelectric patches 6 positive and negative polarities are drawn, it is characterized in that: sensor unit shell 1 is the hollow wedge; The wide end of described sensor unit shell 1 is positioned at the outside of annular, the narrow end of sensor unit shell 1 is positioned at the inboard of annular, and narrow end opening, slide block 3 is positioned at sensor unit shell 1, the internal fixation of slide block 3 has pin 4, and slide block 3 is provided with can be along the chute of described pin 4 slips, and chute is connected with described pin 4, described slide block 3 slides along pin 4 and stretches out sensor unit shell 1, is mounted with spring 2 between the wide end of the top of slide block 3 and sensor unit shell 1; The narrow end place that slide block 3 is positioned at sensor unit shell 1 is provided with T type groove, and piezoelectric patches 6 places in the described T type groove, and the arranged outside of piezoelectric patches 6 has the protective seam 7 of avoiding causing when contacting with the grounded screen round steel bar damage.
Described grounded screen round steel bar corrosion detects self-adapted sensor, and it is characterized in that: the material of sensor unit shell 1 is aluminium alloy or stainless steel.
Described grounded screen round steel bar corrosion detects self-adapted sensor, and it is characterized in that: the material of described slide block 3 is stainless steel.
Described grounded screen round steel bar corrosion detects self-adapted sensor, it is characterized in that: piezoelectric patches 6 adopts telescopic type PZT-5A piezoelectric ceramic piece, and length * wide * height is of a size of 28mm * 2.4mm * 0.5mm.
Described grounded screen round steel bar corrosion detects self-adapted sensor, it is characterized in that: the big first side design of the wedge on the described sensor unit shell 1 has two pin-and-holes, passes through pivot pin 8 coordination hinges in above-mentioned two pin-and-holes between the sensor unit.
Described grounded screen round steel bar corrosion detects self-adapted sensor, it is characterized in that: sensor unit shell 1 and slide block 3 adopt clearance fit, and spring 2 is pretension when mounted.
The corrosion of described grounded screen round steel bar detects self-adapted sensor, it is characterized in that: pin 4 and shell 1 interference fit and slide block 3 clearance fit, slide block 3 are subjected to the length that sensor unit shell 1 is stretched out in the restriction adjustment of pin 4 and spring 2.
Described grounded screen round steel bar corrosion detects self-adapted sensor, and it is characterized in that: piezoelectric patches 6 pastes protective seam 7 inboards by bonding agent, and protective seam 7 sticks in the T type groove of slide block 3 front ends reservation by bonding agent.Bonding piezoelectric patches 6 is fixed on the protective seam 7, is between protective seam 7 and the slide block 3, and the effect of protective seam 7 is protection piezoelectric patches 6.Protective seam 7 is directly with the contact of grounded screen round steel bar, and excitation and reception signal transmit by protective seam 7 and finish during piezoelectric patches 6 work.
Described grounded screen round steel bar corrosion detects self-adapted sensor, it is characterized in that: the detected diameter of foundation is the grounded screen rod iron 9 of 14-28mm, chooses 8 to 16 sensor units by pivot pin 8 hinged forming.
The beneficial effects of the utility model are: sensor has been realized installing from grounded screen round steel bar side; In use, can select for use the sensor unit of varying number to form sensor according to the difference of detected grounded screen round steel bar diameter; Spring pretension and slide block type design can be so that realize between sensor and the grounded screen round steel bar that fine setting is to reach excellent contact.
Description of drawings
Fig. 1 is the sensor unit sectional view;
Fig. 2 is sensor installation and measuring synoptic diagram;
Fig. 3 is the sensor unit explosive view;
Fig. 4 is the sensor unit front view;
Fig. 5 is sensor unit left side pseudosection;
Fig. 6 is the sensor unit vertical view;
Among the figure: 1, sensor unit shell, 2, spring, 3, slide block, 4, pin, 5, lead-in wire, 6, piezoelectric patches, 7, protective seam, 8, pivot pin, 9, the grounded screen round steel bar
Embodiment
Below by specific embodiment the utility model is described in further detail, following examples be descriptive be not determinate, can not limit protection domain of the present utility model with this.
By Fig. 1, Fig. 2, Fig. 3; Fig. 4; Fig. 5, grounded screen round steel bar corrosion shown in Figure 6 detects self-adapted sensor and is made of sensor unit, and each sensor unit comprises sensor unit shell 1, spring 2, slide block 3, pin 4, lead-in wire 5, piezoelectric patches 6, protective seam 7, pivot pin 8.Sensor unit shell 1 is the big hollow wedge of a little tail; Settle a pair of spring 2 between sensor unit shell 1 and the slide block 3; Slide block 3 is fixed on the sensor unit shell 1 by a pair of pin 4; A plurality of sensor units connect to form sensor by pivot pin 8.
The utility model sensor mounting technology scheme is seen Fig. 3.The first step the two poles of the earth is welded upward lead-in wire 5 with piezoelectric patches about in the of 6.Solder joint is tried one's best little and smooth, will weld 5 piezoelectric patches 6 usefulness 502 gluing being attached on the protective seam 7 of going between, with an end align center wherein.Second step bonded to piezoelectric patches 6, lead-in wire 5 and the protective seam 7 that combines in the T type groove of slide block 3, and lead-in wire 5 is passed from the hole that slide block 3 centers are reserved.The 3rd step, two springs 2 are put into the cavity of shell 1, place shell 1 to compress slide block 3, pin 4 is passed the pin-and-hole that shell 1 and slide block 3 are reserved, lead-in wire 5 is drawn from the threaded hole of outer casing bottom central authorities.So far, sensor unit is just assembled and has been finished.The 4th step, with 13 sensor units assembling with the pivot pin 8 formation sensor that is together in series.
Described sensor outer housing 1 uses aluminium alloy; Slide block 3 uses stainless steel; Piezoelectric patches 6 adopts telescopic type PZT-5A piezoelectric ceramic piece, and length * wide * height is of a size of 6mm * 2.4mm * 0.5mm.
Described shell 1 is the hollow wedge, and the big first side of wedge designs two place's pin-and-holes, and two place's pin-and-holes can coordination hinge.Two Φ 3mm blind holes of outer casing bottom design are used for the location and installation spring.Bottom center is opened a M4 threaded hole, is used for lead-in wire 5 and external connection interface section.Shell 1 and slide block 3 adopt clearance fit, and spring 2 is pretension when mounted.
Described pin 4 and shell 1 interference fit and slide block 3 clearance fit, slide block 3 is subjected to the restriction of pin 4 and spring 2 can adjust the length of stretching out shell.
Described spring 2 length are 8mm, and diameter is 2.5mm, and lead-in wire 5 is the enameled wire of Φ 0.45mm, and protective seam 7 length * wide * height are of a size of the corundum sheet of 14mm * 4mm * 0.5mm.
Described piezoelectric patches 6 pastes on the protective seam 7 by bonding agent, and protective seam 7 and slide block 3 pass through adhesive securement.
Described sensor is the grounded screen rod iron 9 of Φ 22mm according to detected diameter, chooses 13 sensor units by pivot pin 8 hinged forming.
Select the right sensors element number for use according to the diameter of grounded screen round steel bar when checking, the spring between shell and the slide block can make slide block make trickle adjustment according to the rod iron diameter when detecting, and makes that self-adaptation contacts between sensor and the detected rod iron.When reality was used, 8 to 16 sensor units were formed sensor, and going for diameter is the Non-Destructive Testing of the model grounded screen rod iron commonly used of Φ 14-28mm, and the realization sensor is circumferential uniform load mode along the round steel bar side.Making that supersonic guide-wave Non-Destructive Testing mode can apply to that the grounded screen round steel bar is this can't be from the detected object of end face placement sensor.
Sensor is melted in this utility model invention and jig is one, make that sensor bulk is small and exquisite, it is easy, easy-to-use to install, detect fast, can detect the grounded screen round steel bar efficiently, simultaneously because but this sensor adapts to the grounded screen round steel bar self-adaptation fine setting of plurality of specifications, simultaneously this sensor low cost of manufacture, good stability, can reuse, so in practical project detects, can well be used.
Claims (9)
1. the corrosion of grounded screen round steel bar detects self-adapted sensor, it is characterized in that: it is by the hinged annular of forming of pivot pin (8) by a plurality of sensor units, wherein each sensor unit comprise sensor unit shell (1), slide block (3), piezoelectric patches (6), from the lead-in wire (5) that piezoelectric patches (6) positive and negative polarities are drawn, it is characterized in that: sensor unit shell (1) is the hollow wedge; The wide end of described sensor unit shell (1) is positioned at the outside of annular, the narrow end of sensor unit shell (1) is positioned at the inboard of annular, and narrow end opening, slide block (3) is positioned at sensor unit shell (1), the internal fixation of slide block (3) has pin (4), slide block (3) is provided with can be along the chute of described pin (4) slip, chute is connected with described pin (4), described slide block (3) slides along pin (4) and stretches out sensor unit shell (1), is mounted with spring (2) between the wide end of the top of slide block (3) and sensor unit shell (1); The narrow end place that slide block (3) is positioned at sensor unit shell (1) is provided with T type groove, and piezoelectric patches (6) places in the described T type groove, and the arranged outside of piezoelectric patches (6) has the protective seam (7) of avoiding causing when contacting with the grounded screen round steel bar damage.
2. grounded screen round steel bar corrosion as claimed in claim 1 detects self-adapted sensor, and it is characterized in that: the material of sensor unit shell (1) is aluminium alloy or stainless steel.
3. grounded screen round steel bar corrosion as claimed in claim 1 detects self-adapted sensor, and it is characterized in that: the material of described slide block (3) is stainless steel.
4. grounded screen round steel bar corrosion as claimed in claim 1 detects self-adapted sensor, it is characterized in that: piezoelectric patches (6) adopts telescopic type PZT-5A piezoelectric ceramic piece, and length * wide * height is of a size of 28mm * 2.4mm * 0.5mm.
5. grounded screen round steel bar corrosion as claimed in claim 1 detects self-adapted sensor, it is characterized in that: the big first side design of the wedge on the described sensor unit shell (1) has two pin-and-holes, passes through pivot pin (8) coordination hinge in above-mentioned two pin-and-holes between the sensor unit.
6. grounded screen round steel bar corrosion as claimed in claim 1 detects self-adapted sensor, and it is characterized in that: sensor unit shell (1) and slide block (3) adopt clearance fit, and spring (2) is pretension when mounted.
7. grounded screen round steel bar corrosion as claimed in claim 1 detects self-adapted sensor, it is characterized in that: pin (4) and shell (1) interference fit, and slide block (3) clearance fit, the length of sensor unit shell (1) is stretched out in the restriction adjustment that slide block (3) is subjected to pin (4) and spring (2).
8. grounded screen round steel bar corrosion as claimed in claim 1 detects self-adapted sensor, it is characterized in that: piezoelectric patches (6) pastes protective seam (7) inboard by bonding agent, and protective seam (7) sticks in the T type groove of slide block (3) front end reservation by bonding agent; Bonding piezoelectric patches (6) is fixed on the protective seam (7), is between protective seam (7) and the slide block (3), and the effect of protective seam (7) is that protection piezoelectric patches (6) is not damaged in use; Protective seam (7) is directly with the contact of grounded screen round steel bar, and the vibration signal of excitation and reception transmits by protective seam (7) during piezoelectric patches (6) work; Piezoelectric patches (6) excitation is connected with the reception instrument by lead-in wire (5) with the electric signal that receives.
9. grounded screen round steel bar corrosion as claimed in claim 1 detects self-adapted sensor, and it is characterized in that: the detected diameter of foundation is the grounded screen rod iron (9) of 14-28mm, chooses 8 to 16 sensor units by hinged the forming of pivot pin (8).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN 201220721960 CN203148900U (en) | 2012-12-24 | 2012-12-24 | Self-adaptive sensor for detecting grounding grid round steel bar corrosion |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220721960 CN203148900U (en) | 2012-12-24 | 2012-12-24 | Self-adaptive sensor for detecting grounding grid round steel bar corrosion |
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| CN203148900U true CN203148900U (en) | 2013-08-21 |
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| CN 201220721960 Expired - Lifetime CN203148900U (en) | 2012-12-24 | 2012-12-24 | Self-adaptive sensor for detecting grounding grid round steel bar corrosion |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111855710A (en) * | 2020-07-31 | 2020-10-30 | 洛阳欣隆工程检测有限公司 | DR real-time detection system for field large-diameter pipeline weld joint |
-
2012
- 2012-12-24 CN CN 201220721960 patent/CN203148900U/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111855710A (en) * | 2020-07-31 | 2020-10-30 | 洛阳欣隆工程检测有限公司 | DR real-time detection system for field large-diameter pipeline weld joint |
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| GR01 | Patent grant | ||
| CX01 | Expiry of patent term |
Granted publication date: 20130821 |
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| CX01 | Expiry of patent term |