CN113655123A - System and method for detecting longitudinal linear defects of inner wall surface of boiler membrane type pipe on fire facing side - Google Patents
System and method for detecting longitudinal linear defects of inner wall surface of boiler membrane type pipe on fire facing side Download PDFInfo
- Publication number
- CN113655123A CN113655123A CN202111076670.8A CN202111076670A CN113655123A CN 113655123 A CN113655123 A CN 113655123A CN 202111076670 A CN202111076670 A CN 202111076670A CN 113655123 A CN113655123 A CN 113655123A
- Authority
- CN
- China
- Prior art keywords
- wall
- membrane type
- type pipe
- boiler membrane
- facing side
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/04—Analysing solids
- G01N29/041—Analysing solids on the surface of the material, e.g. using Lamb, Rayleigh or shear waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/22—Details, e.g. general constructional or apparatus details
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/22—Details, e.g. general constructional or apparatus details
- G01N29/30—Arrangements for calibrating or comparing, e.g. with standard objects
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Acoustics & Sound (AREA)
- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
Abstract
The invention discloses a system and a method for detecting longitudinal linear defects of the surface of an inner wall of a boiler membrane type pipe on a fire facing side, wherein the system comprises an acoustic-transparent wedge block, an ultrasonic transducer, an ultrasonic detector and a comparison test block for setting and calibrating the ultrasonic detector; the system and the method can realize the detection of the longitudinal linear defect on the surface of the inner wall of the boiler membrane type pipe facing to the fire side, and have the characteristics of low cost and higher detection accuracy.
Description
Technical Field
The invention belongs to the field of ultrasonic detection, and relates to a system and a method for detecting longitudinal linear defects of the surface of an inner wall of a boiler membrane type pipe on a fire facing side.
Background
The water-cooled wall and the wall-covering tube panel of the power station boiler are basically membrane tubes, the membrane tubes are fin tubes welded by using tubes and flat steel, and then a plurality of fin tubes are sequentially welded along the longitudinal direction to form a whole heating surface tube panel.
When the film type tube for the power station boiler is in service in operation, the inner wall of the fire facing side of the tube often has surface linear defects, the situation that the tube mainly bears internal pressure is considered, the circumferential stress of the tube is twice of the axial stress, and the tube generally longitudinally cracks, so that the existence of the longitudinal linear defects of the inner wall of the fire facing side brings great potential safety hazards to the stable operation of the boiler, if the longitudinal linear defects of the inner wall cannot be detected and eliminated in time, when the longitudinal linear defects of the inner wall extend to a certain critical value, the extension speed of the longitudinal linear defects of the inner wall suddenly increases, and finally, tube explosion occurs to cause non-stop of the boiler. Therefore, the method has extremely important significance for timely detecting the linear defect of the longitudinal surface of the inner wall of the fire facing side of the film type pipe.
At present, a conventional A-type pulse ultrasonic transverse wave or small-angle longitudinal wave detection method is generally adopted for detecting linear defects of the inner wall of a membrane type pipe of a boiler, the two detection methods can only detect the defects of the inner wall covered by sound waves at a probe placing position and cannot detect the defects of the inner wall of a fire-facing surface from a fire-facing surface of the pipe, a scaffold or a hanging basket needs to be erected in a large area in a limited space inside a boiler hearth to detect the defects of the inner wall of the fire-facing surface, the detection environment is severe, the progress is slow, the cost is high, the risk is large, the conventional A-type pulse ultrasonic transverse wave detection has high requirements on skills of detection personnel, the inner wall can be ensured to be scanned only when 100% of the energy converter covers the outer wall of the pipe, the detection result is low in accuracy, the detection efficiency is low, and missing detection (a fin blocking part) exists. The temperature-variable resistor array scanning technology is applied to film type pipe online monitoring in foreign countries, but the technology can only detect large-area corrosion of the inner wall of the pipe, thinning of the pipe wall and the like, can not detect the longitudinal linear defect with high harmfulness, and has the defects of high investment, long-term monitoring and maintenance of personnel, high limitation and the like.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a system and a method for detecting the longitudinal linear defect of the inner wall surface of the boiler membrane type pipe on the fire facing side.
In order to achieve the aim, the system for detecting the linear defects on the longitudinal surface of the inner wall of the boiler membrane type pipe on the fire facing side comprises a sound-transmitting wedge block, an ultrasonic transducer, an ultrasonic detector and a test block for setting and calibrating the ultrasonic detector;
the transmitting wafer and the receiving wafer in the ultrasonic transducer are both located in the sound-transmitting wedge block, the transmitting wafer and the receiving wafer are distributed in an inclined mode, a sound insulation layer is arranged between the transmitting wafer and the receiving wafer, the ultrasonic transducer is connected with an ultrasonic detector, the transmitting wafer and the receiving wafer are symmetrically distributed relative to the sound insulation layer, a longitudinal wire slot is formed in the inner wall of the comparison test block, and when the sound-transmitting wedge block is detected, the sound-transmitting wedge block is buckled on the back fire surface of a boiler membrane type pipe to be detected.
The test block and the boiler membrane type pipe to be tested are the same in material and specification.
The outer diameters of the test block and the boiler membrane type pipe to be tested are both 30-65 mm.
The wall thickness of the test block and the wall thickness of the boiler membrane type pipe to be tested are both 4-10 mm.
The inner walls of the test block and the membrane type pipe of the boiler to be tested are light pipes.
The linear defect of the inner wall surface of the boiler membrane type pipe to be detected is a longitudinal defect with an included angle of not more than 30 degrees with the axis.
The ultrasonic transducer is a double-crystal bidirectional transducer.
The emitting chip and the receiving chip are made of the same material and have the same size.
The working frequency of the transmitting chip and the receiving chip is 2-5 MHz.
And a coupling agent layer is arranged on the back fire surface of the membrane type pipe of the boiler to be detected.
The invention discloses a system and a method for detecting linear defects of longitudinal surfaces of inner walls of boiler membrane type tubes on the fire facing side, which comprises the following steps:
firstly exciting a surface wave on the inner wall of a reference block by an ultrasonic transducer, calibrating the surface wave by utilizing a longitudinal wire slot on the inner wall of the reference block, and then detecting the inner wall of the boiler membrane type pipe to be detected by using the surface wave so as to judge whether the inner wall of the boiler membrane type pipe on the fire facing side has the longitudinal surface linear defect.
The invention has the following beneficial effects:
the invention relates to a system and a method for detecting linear defects of longitudinal surfaces of inner walls of boiler membrane type tubes on the fire facing side, which are used for detecting the linear defects of the longitudinal surfaces of the inner walls of the boiler membrane type tubes on the fire facing side by an ultrasonic detection technology. It should be noted that the invention not only has high accuracy and resolution ratio for defect detection, but also can realize accurate detection of longitudinal linear defects of the inner wall of the fire facing side of the membrane type pipe from the outside of the boiler furnace without missing detection, and does not need to set up auxiliary platforms such as scaffolds or hanging baskets and the like in the limited space of the furnace, thereby greatly saving the detection cost and improving the detection environment.
Drawings
FIG. 1 is a schematic structural diagram of the present invention.
Wherein, 1 is an ultrasonic transducer, 2 is a sound insulation layer, 3 is a transmitting wafer, 4 is a receiving wafer, 5 is a sound transmission wedge block, 6 is a comparison test block, and 7 is a longitudinal wire casing.
Detailed Description
In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments, and are not intended to limit the scope of the present disclosure. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present disclosure. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
There is shown in the drawings a schematic block diagram of a disclosed embodiment in accordance with the invention. The figures are not drawn to scale, wherein certain details are exaggerated and possibly omitted for clarity of presentation. The shapes of various regions, layers and their relative sizes and positional relationships shown in the drawings are merely exemplary, and deviations may occur in practice due to manufacturing tolerances or technical limitations, and a person skilled in the art may additionally design regions/layers having different shapes, sizes, relative positions, according to actual needs.
Referring to fig. 1, the system and method for detecting linear defects on the longitudinal surface of the inner wall of the boiler membrane type tube on the fire facing side comprises an acoustic-transparent wedge 5, an ultrasonic transducer 1, an ultrasonic detector and a reference block 6 for setting and calibrating the ultrasonic detector;
when detecting, the sound transmission wedge block 5 is buckled on the back fire surface of the boiler membrane type pipe to be detected, the transmitting wafer 3 and the receiving wafer 4 in the ultrasonic transducer 1 are both positioned in the sound transmission wedge block 5, the transmitting wafer 3 and the receiving wafer 4 are both distributed in an inclined mode, a sound insulation layer 2 is arranged between the transmitting wafer 3 and the receiving wafer 4, the ultrasonic transducer 1 is connected with an ultrasonic detector, and a coupling agent layer is arranged on the outer wall of the back fire surface of the boiler membrane type pipe to be detected.
The ultrasonic transducer 1 is a double-crystal bidirectional transducer, the transmitting wafer 3 and the receiving wafer 4 are made of the same material and have the same size, the working frequencies of the transmitting wafer 3 and the receiving wafer 4 are both 2-5 MHz, and the transmitting wafer 3 and the receiving wafer 4 are obliquely and symmetrically distributed relative to the sound insulation layer 2.
The reference block 6 is the same as the boiler membrane type pipe to be tested in material and specification, and a longitudinal wire slot 7 is formed in the inner wall of the fire facing surface of the reference block.
The outer diameters of the comparison test block 6 and the boiler membrane type pipe to be tested are 30-65 mm, the wall thickness is 4-10 mm, and the inner walls of the comparison test block 6 and the boiler membrane type pipe to be tested are light pipes.
The invention discloses a system and a method for detecting linear defects of longitudinal surfaces of inner walls of boiler membrane type tubes on the fire facing side, which comprises the following steps:
firstly exciting a surface wave on the inner wall of a reference test block 6 through an ultrasonic transducer 1, calibrating the surface wave by utilizing a longitudinal wire slot 7 on the inner wall of the reference test block 6, and then detecting the inner wall of a boiler membrane type pipe to be detected by utilizing the surface wave so as to judge whether the inner wall of the boiler membrane type pipe on the fire facing side has the longitudinal surface linear defect.
Example one
The standard of the reference block 6 is phi 48 multiplied by 7.5mm, the material is 15CrMoG, and a longitudinal wire slot 7 with the length, width and height of 10 multiplied by 0.2mm is processed on the inner wall of the fire facing side of the reference block 6;
the ultrasonic detector has the functions of narrow pulse excitation and broadband amplification, the HS610e ultrasonic detector is selected in the embodiment, the ultrasonic transducer 1 is a high-damping narrow pulse bidirectional bimorph transducer, the frequency is 2.5P, the wafer size is 6 multiplied by 6mm, and the refraction angle beta of the transducer is sin-1r/R＝sin-1The refraction angle of the ultrasonic transducer 1 ensures that the transverse wave emitted by the transmitting wafer 3 excites a surface wave on the inner wall of the reference block, namely, 43.4 DEG at 16.5/24.
During testing, the ultrasonic transducer 1 is connected with an ultrasonic detector, foreign matters and rust on the outer wall of the back fire side of the reference block 6 are cleaned, the sound-transmitting wedge 5 is completely coupled with the outer wall of the reference block 6, a coupling agent is coated on the moving area of the ultrasonic transducer 1, and the working mode of the ultrasonic detector is set to be a transmitting-receiving mode; calibrating the ultrasonic detector by using the longitudinal line slot 7 on the inner wall of the fire-facing side of the comparison test block 6, placing the ultrasonic transducer 1 at the forward position of the outer wall of the fire-facing side of the comparison test block 6, finding the highest wave of the longitudinal line slot 7 on the inner wall, adjusting the zero offset of the ultrasonic detector to enable the sound path display value of the highest wave to be the half perimeter of the test block, namely pi R/2 is 3.14 multiplied by 48/2 and approximately equals to 75.4mm, and then adjusting the display range of the ultrasonic detector to enable the highest wave of the longitudinal line slot 7 to be at the middle position of the horizontal coordinate of the display screen; and finally, adjusting the gain of the ultrasonic detector to enable the amplitude of the highest wave of the longitudinal wire casing 7 to be 80% of full screen, setting the current gain as the ultrasonic detection sensitivity, and finishing the setting and calibration of the ultrasonic detector and the ultrasonic transducer 1.
Placing an ultrasonic transducer 1 at the positive position of the outer wall of the side of the back fire surface of the boiler membrane tube to be detected for scanning, wherein the scanning modes are non-parallel scanning and parallel scanning, and the moving direction of the ultrasonic transducer 1 is vertical to the axis of the boiler membrane tube to be detected during the non-parallel scanning, namely the moving method of the ultrasonic transducer 1 is vertical to the direction of the sound beam; during parallel scanning, the moving direction of the ultrasonic transducer 1 is parallel to the perimeter of the boiler membrane type pipe to be detected, namely the moving method of the ultrasonic transducer 1 is parallel to the sound beam direction; the non-parallel scanning is used as an initial scanning mode and is used for rapid detection and length measurement of defects, and the parallel scanning is used for accurately judging whether the original sound wave display is a one-transmission and one-receiving sound wave display or the defect display aiming at the found sound wave display. In the scanning process, the scanning speed is not more than 150mm/s, and when the display screen of the ultrasonic detector has defect sound wave display with the wave amplitude not less than 80% of the full screen, the current detection position of the boiler membrane type pipe to be detected has the inner wall longitudinal linear defect with the depth not less than 0.2 mm.
The invention has the following advantages:
1) the method is feasible for detecting the longitudinal surface linear defect of the inner wall of the fire facing side from the outer wall of the fire facing side of the film type tube by exciting the surface wave by adopting the one-transmitting-one-receiving mode bidirectional double-crystal transducer, no introduction about the method is provided at home at present, and the detection technology has certain research value;
2) compared with the conventional detection method, the method can realize 100% detection of the linear defects of the longitudinal surface of the inner wall of the fire-facing surface from the outer wall of the back fire surface of the boiler membrane type pipe, does not need to set up a scaffold or a hanging basket in a large area in the limited space in the boiler hearth to solve the detection of the defects of the inner wall of the fire-facing surface, and greatly improves the safety, the economy and the detection efficiency.
Claims (10)
1. A boiler membrane type pipe fire facing side inner wall longitudinal surface linear defect detection system and method is characterized by comprising an acoustic-transparent wedge block (5), an ultrasonic transducer (1), an ultrasonic detector and a reference block (6) for setting and calibrating the ultrasonic detector;
transmitting wafer (3) and receiving wafer (4) in ultrasonic transducer (1) all are located sound transmission voussoir (5), transmitting wafer (3) and receiving wafer (4) all incline to distribute, just be provided with sound insulating layer (2) between transmitting wafer (3) and receiving wafer (4), ultrasonic transducer (1) is connected with ultrasonic detector, transmitting wafer (3) and receiving wafer (4) for sound insulating layer (2) symmetric distribution, be provided with vertical wire casing (7) on the inner wall of comparison test block (6), when examining, sound transmission voussoir (5) lock is on the back fire face of the boiler membrane pipe that awaits measuring.
2. The system and the method for detecting the linear defects on the longitudinal surface of the inner wall of the boiler membrane type pipe on the fire facing side are characterized in that the material and the specification of the reference block (6) and the boiler membrane type pipe to be detected are the same.
3. The system and the method for detecting the linear defects on the longitudinal surface of the inner wall of the boiler membrane type pipe on the fire facing side are characterized in that the outer diameters of the reference block (6) and the boiler membrane type pipe to be detected are both 30-65 mm.
4. The system and the method for detecting the linear defects on the longitudinal surface of the inner wall of the boiler membrane type pipe on the fire facing side are characterized in that the wall thickness of the reference block (6) and the wall thickness of the boiler membrane type pipe to be detected are both 4-10 mm.
5. The system and the method for detecting the linear defects on the longitudinal surface of the inner wall of the boiler membrane type pipe on the fire facing side are characterized in that the reference block (6) and the inner wall of the boiler membrane type pipe to be detected are light pipes.
6. The system and the method for detecting the linear defects on the longitudinal surface of the inner wall of the boiler membrane type pipe on the fire facing side according to the claim 1, wherein the linear defects on the inner wall of the boiler membrane type pipe on the fire facing side to be detected are longitudinal defects, namely, the included angle between the surface linear defects and the axis of the boiler membrane type pipe to be detected is not more than 30 degrees.
7. The system and the method for detecting the linear defects on the longitudinal surface of the inner wall of the boiler membrane type pipe on the fire facing side are characterized in that the ultrasonic transducer (1) is a two-crystal two-way transducer.
8. The system and the method for detecting the linear defects on the longitudinal surface of the inner wall of the boiler membrane type pipe on the fire facing side are characterized in that the emitting wafer (3) and the receiving wafer (4) are the same in material and size.
9. The system and the method for detecting the linear defects on the longitudinal surface of the inner wall of the boiler membrane type pipe on the fire facing side are characterized in that the working frequency of the transmitting wafer (3) and the working frequency of the receiving wafer (4) are both 2-5 MHz;
and a coupling agent layer is arranged on the back fire surface of the membrane type pipe of the boiler to be detected.
10. The method and the system for detecting the linear defects of the longitudinal surface of the inner wall of the boiler membrane type pipe on the fire facing side are characterized by comprising the following steps of:
firstly exciting a surface wave on the inner wall of a reference block (6) through an ultrasonic transducer (1), calibrating the surface wave by utilizing a longitudinal wire slot (7) on the inner wall of the reference block (6), and then detecting the inner wall of the boiler membrane type pipe to be detected by utilizing the surface wave to judge whether the inner wall of the boiler membrane type pipe on the fire facing side has longitudinal surface linear defects.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111076670.8A CN113655123A (en) | 2021-09-14 | 2021-09-14 | System and method for detecting longitudinal linear defects of inner wall surface of boiler membrane type pipe on fire facing side |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111076670.8A CN113655123A (en) | 2021-09-14 | 2021-09-14 | System and method for detecting longitudinal linear defects of inner wall surface of boiler membrane type pipe on fire facing side |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113655123A true CN113655123A (en) | 2021-11-16 |
Family
ID=78483730
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111076670.8A Pending CN113655123A (en) | 2021-09-14 | 2021-09-14 | System and method for detecting longitudinal linear defects of inner wall surface of boiler membrane type pipe on fire facing side |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113655123A (en) |
-
2021
- 2021-09-14 CN CN202111076670.8A patent/CN113655123A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6138514A (en) | Tube flaw detecting method using two probes | |
| US7950284B2 (en) | Inspection device and method for inspection | |
| CN108548869B (en) | Nuclear power station polyethylene pipe phased array ultrasonic detection method | |
| CN105181799B (en) | The transverse defect detection means and method of Cylinder Surface workpiece | |
| CN105938122A (en) | Thin-walled small-diameter tube phased array detection reference block | |
| CN207020131U (en) | Thin-walled tube girth joint phased array ultrasonic detection reference block | |
| CN105136903A (en) | Cylindrical curved surface work-piece butt joint welding seam lateral defect detection apparatus and cylindrical curved surface work-piece butt joint welding seam lateral defect detection method | |
| CN105353035A (en) | Method for detecting TKY tube node by using phased array | |
| CN103115963A (en) | Method for detecting welding seam of resistance weld pipe through creeping wave and creeping wave probe for method | |
| CN105241964B (en) | The delay calculating method of cylindrical surface workpiece phase-control focusing ultrasound detection | |
| CN206710388U (en) | The ultrasonic wave detecting system of small diameter tube outside weld sliding block angle welding | |
| CN106706759B (en) | Method for evaluating defects of welding joint of P92 steel main steam pipeline of ultra-supercritical generator set | |
| CN215985876U (en) | Boiler membrane type pipe fire facing side inner wall surface longitudinal linear defect detection system | |
| CN105717197A (en) | Ultrasonic detection method for thick-walled tube girth weld surface defect diffraction time difference | |
| CN113884035A (en) | Ultrasonic detection system and detection method for thick-wall pipe | |
| CN113655123A (en) | System and method for detecting longitudinal linear defects of inner wall surface of boiler membrane type pipe on fire facing side | |
| CN101793871A (en) | Ultrasonic testing method for butt-jointed seam of steel tube tower in electric transmission line | |
| WO2023274089A1 (en) | Curved-surface sonolucent wedge design method for circumferential ultrasonic detection of small-diameter tube | |
| CN115047071A (en) | Detection device and detection method for plug-in fillet weld of thick-wall pressure-bearing equipment | |
| CN114894901A (en) | In-service basin-type insulator defect phased array detection and operation life evaluation method | |
| JPH04142456A (en) | Ultrasonic flaw detection for metal tube | |
| JP2000352563A (en) | Ultrasonic flaw detector for cladding tube | |
| CN113466341A (en) | Radial crack creeping wave detection method for outer wall of opening of steam-water pipeline seat | |
| CN113155965A (en) | Single-side single-side phased array ultrasonic detection method for dissimilar steel welding seam of small-diameter pipe | |
| CN213398333U (en) | System for detecting circumferential defects on inner arc surface of small-diameter pipe elbow |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |