CN111855806B - Ultrasonic detection method for brazing of generator bridging strands - Google Patents
Ultrasonic detection method for brazing of generator bridging strands Download PDFInfo
- Publication number
- CN111855806B CN111855806B CN202010767918.4A CN202010767918A CN111855806B CN 111855806 B CN111855806 B CN 111855806B CN 202010767918 A CN202010767918 A CN 202010767918A CN 111855806 B CN111855806 B CN 111855806B
- Authority
- CN
- China
- Prior art keywords
- ultrasonic
- transducer
- detection
- detected
- generator
- 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.)
- Active
Links
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
-
- 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
- G01N29/28—Details, e.g. general constructional or apparatus details providing acoustic coupling, e.g. water
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/02—Indexing codes associated with the analysed material
- G01N2291/023—Solids
- G01N2291/0234—Metals, e.g. steel
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/26—Scanned objects
- G01N2291/267—Welds
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 relates to a generator bridging strand brazing ultrasonic detection method, which comprises an ultrasonic detector and two ultrasonic longitudinal wave transducers connected with the ultrasonic detector, wherein the transmitting transducer is used for transmitting pulse ultrasonic waves to an object to be detected, the transmitted pulse ultrasonic waves are received by the receiving transducer after passing through the object to be detected, and the defect severity of the object to be detected are judged according to the intensity of received ultrasonic signals; the method is simple, the sound beam is only transmitted unidirectionally, so that the sound path attenuation is low, a detection blind area does not exist, the method is suitable for detecting high-attenuation materials, the shielding effect of defects is not influenced by factors such as defect roughness or defect azimuth, the method is suitable for detecting internal defects of the welding layer of the welding strand of the generator bridging strand of the thermal power plant, the detection speed is high, the accuracy is high, and the method is an innovation in the ultrasonic detection method for welding the welding strand of the generator bridging strand.
Description
Technical Field
The invention belongs to the technical field of nondestructive testing, and particularly relates to an ultrasonic testing method for brazing layer defects of a water cover and bridging strands of a water and electricity joint of a generator and an L-shaped pressing plate, which is suitable for testing welding quality of the bridging strands of a generator in a thermal power plant.
Background
The welding between the water box cover and the bridging strand and between the bridging strand and the L-shaped pressing plate of the generator of the thermal power plant adopts medium-frequency induction brazing, the main component of the welding material is tin, the welding temperature is 200 ℃, the brazing layer part is an electrical connection point, and the current path is formed, so that the welding defect does not involve water or hydrogen leakage, but the resistance value at the welding position is changed, the resistance value is not obvious for the defect with smaller area, but if the defect area is larger, the defect area accounts for more than 30% of the total welding surface or is severely cracked, the poor contact between the water box cover and the bridging strand is caused, the long-term operation of the unit can lead to the rapid temperature rise of the part, the joint is finally burnt, the unplanned shutdown maintenance of the unit is caused, and the power generation enterprise is brought with larger economic loss and social influence. Therefore, an efficient detection method is sought, internal defects of the generator bridging strand brazing are found in time, and the method has important significance for safe production of power generation enterprises.
The generator water box cover, the bridging folded wires and the L-shaped pressing plate are all copper parts, the grain size difference is large, the main components of welding materials are tin, the welding materials belong to dissimilar steel welding, when the direct probe ultrasonic reflection method is adopted for detection, sound beam attenuation is large, bottom echo is low or completely disappears, signal-to-noise ratio is low, penetrating capacity is reduced, and detection sensitivity cannot be guaranteed. The penetration detection method cannot find defects in the brazing layer, so that defects are missed to be detected, the penetration detection operation intensity is high, and the detection efficiency is low. Therefore, improvements and innovations are necessary.
Disclosure of Invention
Aiming at the situation, in order to overcome the defects of the prior art, the invention aims to provide the ultrasonic detection method for the brazing of the generator bridging strand wires, which can effectively solve the problem of ultrasonic detection of the brazing of the generator bridging strand wires.
The technical scheme of the invention is as follows:
the ultrasonic detection method for brazing the bridging strands of the generator comprises a water box cover, bridging strands and an L-shaped pressing plate, wherein a first bridging strand brazing layer is arranged between the water box cover and the bridging strands, and a second bridging strand brazing layer is arranged between the bridging strands and the L-shaped pressing plate;
the transmitting transducer is used for transmitting pulse ultrasonic waves to the detected object, the transmitted pulse ultrasonic waves penetrate through the detected object and then are received by the receiving transducer, the defect-free and defect severity degree of the detected object is judged according to the intensity of received ultrasonic signals, when the detected object is defect-free, the attenuation of the pulse ultrasonic waves after penetrating is small, the received signals are strong, when the detected object is small in defect, part of sound beams are blocked by the defect in the propagation process of the pulse ultrasonic waves, the receiving transducer can only receive weak signals, and if the detected object is large in area and larger than the defect of the section of the sound beams, all the sound beams are blocked by the defect, and the receiving transducer can not receive the transmitted signals;
the ultrasonic detector is used for detecting and displaying the ultrasonic amplitude received by the receiving transducer after the pulse ultrasonic waves pass through the detected object;
the specific detection method comprises the following steps:
A. cleaning impurities and greasy dirt attached to the detection surfaces of the generator water box cover and the L-shaped pressing plate;
B. performing sound velocity and zero point calibration by adopting a copper block with the same thickness as the detected object, adjusting the reference wave height to 80% of the full screen, and taking the gain of 4dB as the detection sensitivity;
C. uniformly coating ultrasonic coupling agents on two sides of the detected object, namely the bottom surface of the water box cover and the detection surface of the L-shaped pressing plate;
D. the method comprises the steps that a transmitting transducer and a receiving transducer are respectively placed on the bottom surface of a water box cover and the surface of an L-shaped pressing plate on two sides of a detected object, and the transmitting transducer and the receiving transducer are coaxially arranged;
E. the transmitting transducer transmits pulse ultrasonic waves to the detected object, the pulse ultrasonic waves pass through the detected object and are received by the receiving transducer, the water box cover is taken as a detection reference surface, the transmitting transducer is moved at the entity parts at the left side and the right side of the water box cover, meanwhile, the receiving transducer synchronously moves to the coaxial position corresponding to the transmitting transducer, and the diameter position of one transducer is moved each time to detect one point until the moving range covers all the entity parts of the water box cover;
F. if the amplitude of the ultrasonic wave received by the single-point receiving transducer is greater than or equal to 80% of the full screen, the detection of the brazing layer points on two sides of the bridging strand wires is qualified; if the amplitude of the ultrasonic wave received by the single-point receiving transducer is smaller than 80% of the full screen, the detection of the brazing layer points on two sides of the bridging strand wires is judged to be unqualified;
if the qualified points account for more than 80% of the total detection points, the welding quality of the detected parts is qualified; if the qualified points account for less than 80% of the total detection points, the welding quality of the detected parts is unqualified.
Preferably, the working frequency range of the ultrasonic detector is 0.5 MHz-10 MHz, the horizontal linear error is not more than 1%, and the vertical linear error is not more than 5%.
Preferably, the ultrasonic longitudinal wave transducer is a narrow pulse ultrasonic transducer with the diameter of 8mm, and the far field resolution is not less than 30dB.
Preferably, the ultrasonic couplant adopts a CG-98 type couplant, and the couplant with the same specification is adopted in the calibration of the step B and the inspection of the step C.
Preferably, the transmitting transducer and the receiving transducer are fixed on the scanning frame for the ultrasonic detection of the generator bridging strand wire brazing, the scanning frame for the ultrasonic detection of the generator bridging strand wire brazing comprises a circular supporting frame made of elastic materials, a gap which is penetrated inside and outside is formed in one side of the circular supporting frame, the end parts of the circular supporting frames on two sides of the gap are respectively connected with an angle adjusting rod which is arranged in a way of being away from each other and symmetrically inclined, one ends of the two angle adjusting rods, which are away from the circular supporting frame, are hinged with an angle-adjustable transducer supporting rod, the opposite sides of the two angle adjusting rods are respectively fixed with a fixed sleeve for installing an ultrasonic longitudinal wave transducer, the opposite sides of the two angle adjusting rods are respectively provided with a slideway which is arranged along the length direction of the slideway, a slide plate is connected between the slide plates on two sides of the slide plates, one end of the circular supporting frame, which is away from the gap, is fixedly provided with a mounting channel which is penetrated up and down, the center of the circular supporting frame is provided with an angle adjusting screw, the center of the mounting channel is provided with a spherical rotating groove which is outwards protruded, the angle adjusting screw in the mounting channel is fixedly arranged on the spherical rotating groove, and the spherical rotating body in the spherical rotating groove is arranged, the two ends of the angle adjusting screw extend towards the two ends of the screw rod respectively.
Preferably, the axis of the fixed sleeve is perpendicular to the axis of the transducer supporting rod; when the transducer supporting rods on the two sides are parallel to each other, the axes of the two fixed sleeves are collinear, the axes are parallel to the sliding plate, and the axes of the screw rods are perpendicular to the sliding plate.
The method is simple, pulse ultrasonic waves are emitted to the detected object through the emitting transducer, the emitted pulse ultrasonic waves pass through the detected object and then are received by the receiving transducer, the defect-free and defect severity degree of the detected object is judged according to the intensity of the received ultrasonic signals, when the detected object is defect-free, the attenuation of the pulse ultrasonic waves after passing through is small, the received signals are strong, when the detected object has small defects, part of sound beams are blocked by the defects in the propagation process of the pulse ultrasonic waves, the receiving transducer can only receive weak signals, if the detected object has defects with the area larger than the section of the sound beams, all the sound beams are blocked by the defects, and the receiving transducer can not receive the emitted signals.
Drawings
Fig. 1 is a schematic diagram of a generator bridging strand braze detection of the present invention (arrow a indicates the direction of sweep of an ultrasonic longitudinal wave transducer).
Fig. 2 is a schematic diagram of the detection of the cooperation of the scanning frame of the present invention (arrow a indicates the scanning direction of the ultrasonic longitudinal wave transducer).
Fig. 3 is a schematic structural view (partially cut away) of a scanning frame for ultrasonic inspection of generator bridging strand brazing in accordance with the present invention.
Detailed Description
The following describes the embodiments of the present invention in further detail with reference to the drawings.
1-3, the ultrasonic detection method for brazing the generator bridging strands comprises a water box cover 1, bridging strands 2 and an L-shaped pressing plate 3, wherein a first bridging strand brazing layer 4a is arranged between the water box cover 1 and the bridging strands 2, and a second bridging strand brazing layer 4b is arranged between the bridging strands 2 and the L-shaped pressing plate 3, and the ultrasonic detection method further comprises an ultrasonic detector and two ultrasonic longitudinal wave transducers connected with the ultrasonic detector, wherein the two ultrasonic longitudinal wave transducers are a transmitting transducer 5a and a receiving transducer 5b respectively;
the transmitting transducer 5a is configured to transmit a pulse ultrasonic wave to a detected object, where the transmitted pulse ultrasonic wave passes through the detected object and is received by the receiving transducer 5b, and determine whether the detected object has defects or not and the severity of the defects according to the intensity of the received ultrasonic signal, when the detected object has defects, the pulse ultrasonic wave has small attenuation after penetrating, and the received signal is stronger, when the detected object has small defects, part of sound beams are blocked by the defects in the propagation process of the pulse ultrasonic wave, the receiving transducer can only receive weak signals, and if the detected object has defects with an area larger than the cross section of the sound beams, all sound beams will be blocked by the defects, and the receiving transducer cannot receive the transmitted signal;
the ultrasonic detector is used for detecting and displaying the ultrasonic amplitude received by the receiving transducer after the pulse ultrasonic waves pass through the detected object;
the specific detection method comprises the following steps:
A. cleaning impurities and greasy dirt attached to the detection surfaces of the generator water box cover and the L-shaped pressing plate;
B. performing sound velocity and zero point calibration by adopting a copper block with the same thickness as the detected object, adjusting the reference wave height to 80% of the full screen, and taking the gain of 4dB as the detection sensitivity;
C. uniformly coating ultrasonic coupling agents on two sides of the detected object, namely the bottom surface of the water box cover and the detection surface of the L-shaped pressing plate;
D. the transmitting transducer 5a and the receiving transducer 5b are respectively arranged on the bottom surface of the water box cover and the surface of the L-shaped pressing plate on two sides of the detected object, and the transmitting transducer 5a and the receiving transducer 5b are coaxially arranged;
E. the transmitting transducer 5a transmits pulse ultrasonic waves to the detected object, the pulse ultrasonic waves pass through the detected object and are received by the receiving transducer 5b (shown as a detection line 5c in fig. 2), the transmitting transducer is moved at the entity parts at the left side and the right side of the water box cover by taking the water box cover as a detection reference surface, and simultaneously the receiving transducer synchronously moves to the coaxial position corresponding to the transmitting transducer, and a position with the diameter (8 mm) of one transducer is moved each time to detect one point until the moving range covers all the entity parts of the water box cover;
F. if the amplitude of the ultrasonic wave received by the single-point receiving transducer is greater than or equal to 80% of the full screen, the detection of the brazing layer points on two sides of the bridging strand wires is qualified; if the amplitude of the ultrasonic wave received by the single-point receiving transducer is smaller than 80% of the full screen, the detection of the brazing layer points on two sides of the bridging strand wires is judged to be unqualified;
if the qualified points account for more than 80% of the total detection points, the welding quality of the detected parts is qualified; if the qualified points account for less than 80% of the total detection points, the welding quality of the detected parts is unqualified;
and recording detection data according to the detection result, writing a detection report, and if the welding quality of the detected part is unqualified, carrying out subsequent maintenance measures.
In order to ensure the use effect, the working frequency range of the ultrasonic detector is 0.5 MHz-10 MHz, the horizontal linear error is not more than 1%, and the vertical linear error is not more than 5%; this technique is known in the art, such as the USM go+ ultrasonic detector available from and sold by general electric company in the united states.
The diameter of the ultrasonic longitudinal wave transducer is 8mm, and the far-field resolution is not less than 30dB; for example, 5C8N type narrow pulse ultrasonic transducers manufactured and sold by Guangdong Shandong Kogyo Co., ltd.
The parent metals at two sides of the bridging strand brazing layer of the generator are hot rolled red copper plates, and coarse columnar crystals are easy to generate during smelting of the red copper, so that the coarse grains are difficult to eliminate during hot rolling, and the viscosity of the red copper is added, so that the scattering and viscosity absorption attenuation of ultrasonic waves are extremely large, and the sensitivity of ultrasonic flaw detection is seriously affected.
By studying the theory of noise scattering of the ultrasonic structure, it is known that the signal-to-noise ratio can be improved by limiting the interaction probability of coarse grains and ultrasonic beams. Under the condition of a certain pulse repetition frequency, the incident pulse width is reduced, which is equivalent to the weakening of the interference degree and possibility of scattered acoustic pulses of two adjacent grain boundaries on the acoustic wave axis, so that interference effects generated between echoes of the adjacent grain boundaries are also suppressed, and the signal-to-noise ratio of ultrasonic detection is improved. Compared with ultrasonic transducers with different diameters and pulse widths, the narrow pulse ultrasonic transducer with the diameter of 8mm is finally selected, the signal to noise ratio is high, and the ultrasonic transducer is suitable for ultrasonic detection of a generator bridging strand brazing layer.
The error between the combined frequency of the ultrasonic detector and the ultrasonic longitudinal wave transducer and the nominal frequency is not more than +/-10%;
the ultrasonic couplant adopts a CG-98 type couplant, and the couplant with the same specification is adopted in the calibration of the step B and the inspection of the step C.
The ultrasonic detection scanning frame comprises a circular support frame 61 made of elastic materials, an inner and outer through notch 61a is formed in one side of the circular support frame 61, angle adjusting rods 65 which are symmetrically inclined in a mutually far away direction are respectively connected to the end portions of the circular support frame on two sides of the notch 61a, angle-adjustable transducer supporting rods 66 are hinged to one ends of the two angle adjusting rods 65 far away from the circular support frame, fixing sleeves 67 for installing ultrasonic longitudinal wave transducers are fixed on the opposite sides of the two side transducer supporting rods 66, sliding ways 69 which are arranged along the length direction of the two side angle adjusting rods 65 are arranged on the opposite sides of the two side transducer supporting rods 66, sliding blocks 610 which slide forwards and backwards along the length direction of the sliding ways are respectively arranged on the sliding ways 69 on the two sides, sliding plates 62 are connected between the sliding blocks 610 on the two sides, a rotating support sleeve 63 is fixed at one end of the circular support frame 61 far away from the notch, an installing channel which is in a vertically through rotating manner is arranged, an angle adjusting screw 64 is rotatably connected to the installing channel, an outwards-protruding spherical rotating groove is formed in the center of the installing channel, the angle adjusting screw 631 is fixedly arranged on the opposite sides of the installing channel, and the rotating groove is connected with two ends of the rotating screw rods 631, and the rotating direction of the rotating screw rods 631 are respectively.
One end of the angle adjusting screw 64 extending towards the slide plate is provided with a threaded section 641, and the threaded section 641 is in threaded connection with the center of the slide plate; one end of the angle adjusting screw extending away from the slide plate is fixed with a rotating handle 642 for rotation operation.
Handles 611 are fixed on two sides of the circular support 61 respectively, so as to facilitate rotation or pushing operation.
The sliding fit of the sliding block 610 and the sliding way 69 is a conventional technology, for example, a conventional sliding structure such as a T-shaped sliding rail matched with a T-shaped sliding block or a trapezoidal sliding rail matched with a trapezoidal sliding block can be adopted, so that the sliding block is not separated from the sliding way, and can slide back and forth along the length direction of the sliding way under the driving of the sliding plate, thereby synchronously changing the relative angles of the two side angle adjusting rods 65.
The axis of the fixed sleeve 67 is perpendicular to the axis of the transducer support rod 66; when the transducer support bars 66 on both sides are parallel to each other, the axes of the two fixed sleeves 67 are collinear and parallel to the slide plate, while the axis of the screw 64 is perpendicular to the slide plate.
The hinged ends of the angle adjusting rod 65 and the transducer supporting rod 66 are connected with adjusting bolts and compression nuts 68 for fixing the relative positions of the two, namely the angles of the angle adjusting rod 65 and the transducer supporting rod 66 can be adjusted at will, the angles can be compressed and fixed through the adjusting bolts and the compression nuts after adjustment, for example, the angle adjusting rod 65 is hinged with the transducer supporting rod 66 through the adjusting bolts, the angle adjusting rod 65 can axially rotate around the adjusting bolts, and the angle adjusting rod 65 and the transducer supporting rod 66 can be fixed through the compression nuts screwed on the adjusting bolts after the angle adjusting rod 65 and the transducer supporting rod 66 are rotated to a proper angle, and finally the coaxial arrangement of the transmitting transducer 5a and the receiving transducer 5b can be met through the adjustment of the angle;
when in use, the transmitting transducer 5a and the receiving transducer 5b are respectively sleeved in the fixed sleeves 67 at two sides and are pressed and fixed by the fastening bolts screwed at two sides of the fixed sleeves; according to the interval between the bottom surface of the water box cover of the detected object and the surface of the L-shaped pressing plate, the interval between the transmitting transducer and the transmitting end of the receiving transducer is adjusted to be closely attached to the bottom surface of the water box cover and the surface of the L-shaped pressing plate, namely, the interval between the transmitting transducer and the transmitting end of the receiving transducer is equal to or slightly larger than the interval between the bottom surface of the water box cover and the surface of the L-shaped pressing plate (0-1 mm), and the specific adjustment method comprises the following steps: the handle 611 is held by one hand, the angle adjusting screw 64 is rotated by the other hand, and the spherical rotating body 643 limits the axial position of the angle adjusting screw, so that the angle adjusting screw drives the sliding plate in threaded connection with the spherical rotating body 643 to axially slide along the angle adjusting screw, the sliding plate slides to drive the sliding blocks on two sides to synchronously slide back and forth along the length direction of the sliding way, so that the angle adjusting rods 65 on two sides can synchronously open or close, then the transducer supporting rods 66 on two sides are adjusted, the transducer supporting rods on two sides are mutually parallel, the auxiliary adjustment can be realized through a ruler, for example, the distances between the transducer supporting rods on two sides are equal, namely, the mutual parallel can be realized through multipoint measurement, meanwhile, the distance between the transmitting ends of the transmitting transducer 5a and the receiving transducer 5b can meet the requirement, after the adjustment is finished, the adjusting bolts and the compression nuts at the hinged ends of the angle adjusting rods and the transducer supporting rods are screwed, the scanning frame is fixed, then the scanning frame is held by the handle, and the scanning frame is moved according to the method step E, so that the transmitting transducer 5a and the receiving transducer 5b are always kept coaxially in the scanning process, and the detecting accuracy is ensured.
Three copper strips with rectangular cross sections and the same thickness as the water box cover, the bridging folded wires and the L-shaped pressing plate are selected as comparison test samples, the three copper strips are welded together in sequence by adopting a brazing tin welding material, and four groups of defects including cracks, unfused, air holes and slag inclusion are formed at different positions by changing a welding process in the welding process, and each group of copper strips with welding defects are respectively intercepted to be used as test blocks. And cutting three samples at the defect-free part, wherein two samples are provided with artificial defect grooves at different brazing positions. The six groups of test blocks are detected and compared by the method, the test positions are point measurement of the positions of the defects, and the test results show that the method is suitable for detecting welding defects of the brazing layers on two sides of the bridging strand, and the specific test results are shown in the following table:
Claims (5)
1. the utility model provides a generator bridging strand brazing ultrasonic detection method, including lid (1), bridging strand (2) and L type clamp plate (3), be provided with first bridging strand braze welding layer (4 a) between lid (1) and bridging strand (2), be provided with second bridging strand braze welding layer (4 b) between bridging strand (2) and L type clamp plate (3), characterized by that, this method still includes ultrasonic detector and two ultrasonic longitudinal wave transducers that link to each other with it, two ultrasonic longitudinal wave transducers are transmitting transducer (5 a) and receiving transducer (5 b) respectively;
the transmitting transducer (5 a) is used for transmitting pulse ultrasonic waves to an object to be detected, the transmitted pulse ultrasonic waves penetrate through the object to be detected and then are received by the receiving transducer (5 b), the defect-free and defect severity degree of the object to be detected is judged according to the intensity of received ultrasonic signals, when the object to be detected is defect-free, the pulse ultrasonic waves have small attenuation after penetrating, the received signals are stronger, when the object to be detected has small defects, part of sound beams are blocked by the defects in the transmission process of the pulse ultrasonic waves, the receiving transducer can only receive weaker signals, and if the object to be detected has defects with the area larger than the section of the sound beams, all the sound beams are blocked by the defects, and the receiving transducer can not receive the transmitted signals;
the ultrasonic detector is used for detecting and displaying the ultrasonic amplitude received by the receiving transducer after the pulse ultrasonic waves pass through the detected object;
the transmitting transducer (5 a) and the receiving transducer (5 b) are fixed on a scanning frame for ultrasonic detection of generator bridging strand brazing, the scanning frame for ultrasonic detection of generator bridging strand brazing comprises a circular supporting frame (61) made of elastic materials, one side of the circular supporting frame (61) is provided with a notch (61 a) which is penetrated internally and externally, the end parts of the circular supporting frames on two sides of the notch (61 a) are respectively connected with angle adjusting rods (65) which are symmetrically inclined in mutually far away directions, one ends of the two angle adjusting rods (65) far away from the circular supporting frame are hinged with an angle-adjustable transducer supporting rod (66), a fixed sleeve (67) for installing an ultrasonic longitudinal wave transducer is fixed on the opposite sides of the transducer supporting rods (66), a slideway (69) arranged along the length direction of the ultrasonic longitudinal wave transducer is arranged on the opposite sides of the angle adjusting rods (65), sliding blocks (610) sliding forwards and backwards along the length direction of the slideway are respectively arranged on the slideways (69) on the two sides, a sliding plate (62) is connected between the sliding blocks (610) on the two sides, a rotary supporting sleeve (63) is fixed at one end, far away from a gap, of the circular supporting frame (61), an installation channel which penetrates up and down is arranged in the rotary supporting sleeve (63), an angle adjusting screw (64) is rotationally connected to the installation channel, a spherical rotary groove (631) protruding outwards is arranged at the center of the installation channel, a spherical rotating body (643) which is rotatably arranged in the spherical rotating groove (631) is fixed on the angle adjusting screw rod (64) in the installation channel, two ends of the angle adjusting screw rod (64) respectively extend out of two ends of the installation channel, and a screw rod extending towards one end of the sliding plate (62) is in threaded connection with the sliding plate;
the specific detection method comprises the following steps:
A. cleaning impurities and greasy dirt attached to the detection surfaces of the generator water box cover and the L-shaped pressing plate;
B. performing sound velocity and zero point calibration by adopting a copper block with the same thickness as the detected object, adjusting the reference wave height to 80% of the full screen, and taking the gain of 4dB as the detection sensitivity;
C. uniformly coating ultrasonic coupling agents on two sides of the detected object, namely the bottom surface of the water box cover and the detection surface of the L-shaped pressing plate;
D. the method comprises the steps that a transmitting transducer (5 a) and a receiving transducer (5 b) are respectively placed on the bottom surface of a water box cover and the surface of an L-shaped pressing plate on two sides of a detected object, and the transmitting transducer (5 a) and the receiving transducer (5 b) are kept coaxially;
E. the transmitting transducer (5 a) transmits pulse ultrasonic waves to the detected object, the pulse ultrasonic waves pass through the detected object and are received by the receiving transducer (5 b), the transmitting transducer is moved at the entity parts at the left side and the right side of the water box cover by taking the water box cover as a detection reference surface, and simultaneously the receiving transducer synchronously moves to the coaxial position corresponding to the transmitting transducer, and the diameter position of one transducer is detected every time until the moving range covers all entity parts of the water box cover;
F. if the amplitude of the ultrasonic wave received by the single-point receiving transducer is greater than or equal to 80% of the full screen, the detection of the brazing layer points on two sides of the bridging strand wires is qualified; if the amplitude of the ultrasonic wave received by the single-point receiving transducer is smaller than 80% of the full screen, the detection of the brazing layer points on two sides of the bridging strand wires is judged to be unqualified;
if the qualified points account for more than 80% of the total detection points, the welding quality of the detected parts is qualified; if the qualified points account for less than 80% of the total detection points, the welding quality of the detected parts is unqualified.
2. The ultrasonic testing method for brazing of generator bridging strands according to claim 1, wherein the ultrasonic tester has an operating frequency range of 0.5MHz to 10MHz, a horizontal linear error of no more than 1%, and a vertical linear error of no more than 5%.
3. The ultrasonic testing method of generator strand brazing of claim 1, wherein the ultrasonic longitudinal wave transducer is a narrow pulse ultrasonic transducer of 8mm diameter, and the far field resolution is not less than 30dB.
4. The ultrasonic testing method for brazing of generator bridging strands according to claim 1, wherein the ultrasonic couplant is a CG-98 type couplant, and the couplant of the same specification is used in the calibration of step B and the inspection of step C.
5. The ultrasonic testing method of generator span strand brazing according to claim 1, characterized in that the axis of the fixed sleeve (67) is mutually perpendicular to the axis of the transducer support bar (66); when the transducer support rods (66) on two sides are parallel to each other, the axes of the two fixing sleeves (67) are collinear, the axes are parallel to the sliding plate, and the axes of the screw rods (64) are perpendicular to the sliding plate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010767918.4A CN111855806B (en) | 2020-08-03 | 2020-08-03 | Ultrasonic detection method for brazing of generator bridging strands |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010767918.4A CN111855806B (en) | 2020-08-03 | 2020-08-03 | Ultrasonic detection method for brazing of generator bridging strands |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111855806A CN111855806A (en) | 2020-10-30 |
| CN111855806B true CN111855806B (en) | 2023-07-21 |
Family
ID=72953084
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010767918.4A Active CN111855806B (en) | 2020-08-03 | 2020-08-03 | Ultrasonic detection method for brazing of generator bridging strands |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111855806B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113155959B (en) * | 2021-03-10 | 2023-12-22 | 中国大唐集团科学技术研究院有限公司华中电力试验研究院 | Arc fir-type blade root image identification method based on phased array detection |
| KR20240010028A (en) * | 2021-07-20 | 2024-01-23 | 야마하 파인 테크 가부시키가이샤 | Ultrasonic inspection devices and inspection devices |
Citations (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2520509A1 (en) * | 1982-01-27 | 1983-07-29 | Inst Soudure | Ultrasonic automatic analysis of weld faults - using transverse wave emitter-receiver follower displaceable along weld in metallic wall |
| CN1767225A (en) * | 2005-09-23 | 2006-05-03 | 中国人民解放军国防科学技术大学 | Combined type ultrasonic transducer |
| JP2008232825A (en) * | 2007-03-20 | 2008-10-02 | Matsushita Electric Ind Co Ltd | Ultrasonic inspection system |
| CN101655467A (en) * | 2008-08-22 | 2010-02-24 | 中国特种设备检测研究院 | Ray digital imaging detection system for pressure equipment girth welds |
| CN102095798A (en) * | 2010-11-04 | 2011-06-15 | 西安航空动力股份有限公司 | Method for detecting brazing rate of brazed parts by ultrasonic immersed C-scanning |
| RU113008U1 (en) * | 2011-09-12 | 2012-01-27 | Открытое Акционерное Общество "Государственный Ракетный Центр Имени Академика В.П. Макеева" | DEVICE FOR ULTRASONIC CONTROL OF LONGITUDINAL WELDED JOINTS BY MANUAL LONGITUDINAL LATERAL-CROSS-SCAN |
| CN102983478A (en) * | 2012-11-30 | 2013-03-20 | 上海电气电站设备有限公司 | Soldering quality control method of large-section copper strand wire of turbonator |
| CN103529122A (en) * | 2013-09-23 | 2014-01-22 | 中国石油天然气第一建设公司 | Multifunctional double-channel welding line ultrasonic testing scanner |
| CN104597138A (en) * | 2014-12-31 | 2015-05-06 | 钢研纳克检测技术有限公司 | Spiral guided wave electromagnetic ultrasonic transducer for detecting longitudinal and transverse defects of thin-wall steel pipe |
| CN105445375A (en) * | 2015-12-31 | 2016-03-30 | 华南理工大学 | Handheld ultrasonic guided-wave structural damage detection device and detection method using same |
| CN105486399A (en) * | 2015-12-21 | 2016-04-13 | 中北大学 | Micro-capacitance ultrasonic transducer for distance measurement and imaging, and preparation method thereof |
| CN107037127A (en) * | 2017-04-01 | 2017-08-11 | 西南石油大学 | A kind of complex probe formula underwater robot weld defect detection means |
| CN109085241A (en) * | 2018-08-10 | 2018-12-25 | 扬州市紫麓信息技术有限公司 | Special vehicle transmission shaft damage detection apparatus and damage detecting method |
| CN109115872A (en) * | 2017-06-22 | 2019-01-01 | 航天特种材料及工艺技术研究所 | A kind of supersonic detection method of bonding quality |
| CN109254080A (en) * | 2018-10-10 | 2019-01-22 | 南京佳业检测工程有限公司 | A kind of stainless steel ultrasonic detection device |
| CN110018241A (en) * | 2019-05-05 | 2019-07-16 | 广东省特种设备检测研究院（广东省特种设备事故调查中心） | The detection method of large thick-wall container welding point defect based on ultrasonic phase array |
| CN110292397A (en) * | 2019-06-19 | 2019-10-01 | 南京信息职业技术学院 | Chuck device |
| CN209821134U (en) * | 2019-03-03 | 2019-12-20 | 上海九捷精密机械科技有限公司 | Multifunctional test positioning jig |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6912905B2 (en) * | 2003-07-11 | 2005-07-05 | Siemens Westinghouse Power Corporation | Automated tool for ultrasonic inspection of brazed joints |
| GB2431991A (en) * | 2005-11-04 | 2007-05-09 | Imp College Innovations Ltd | Waveguide for ultrasonic non-destructive testing |
| US8301401B2 (en) * | 2010-08-31 | 2012-10-30 | Babcock & Wilcox Technical Services Group, Inc. | Low profile encircling ultrasonic probe for the inspection of in-situ piping in immersion mode |
-
2020
- 2020-08-03 CN CN202010767918.4A patent/CN111855806B/en active Active
Patent Citations (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2520509A1 (en) * | 1982-01-27 | 1983-07-29 | Inst Soudure | Ultrasonic automatic analysis of weld faults - using transverse wave emitter-receiver follower displaceable along weld in metallic wall |
| CN1767225A (en) * | 2005-09-23 | 2006-05-03 | 中国人民解放军国防科学技术大学 | Combined type ultrasonic transducer |
| JP2008232825A (en) * | 2007-03-20 | 2008-10-02 | Matsushita Electric Ind Co Ltd | Ultrasonic inspection system |
| CN101655467A (en) * | 2008-08-22 | 2010-02-24 | 中国特种设备检测研究院 | Ray digital imaging detection system for pressure equipment girth welds |
| CN102095798A (en) * | 2010-11-04 | 2011-06-15 | 西安航空动力股份有限公司 | Method for detecting brazing rate of brazed parts by ultrasonic immersed C-scanning |
| RU113008U1 (en) * | 2011-09-12 | 2012-01-27 | Открытое Акционерное Общество "Государственный Ракетный Центр Имени Академика В.П. Макеева" | DEVICE FOR ULTRASONIC CONTROL OF LONGITUDINAL WELDED JOINTS BY MANUAL LONGITUDINAL LATERAL-CROSS-SCAN |
| CN102983478A (en) * | 2012-11-30 | 2013-03-20 | 上海电气电站设备有限公司 | Soldering quality control method of large-section copper strand wire of turbonator |
| CN103529122A (en) * | 2013-09-23 | 2014-01-22 | 中国石油天然气第一建设公司 | Multifunctional double-channel welding line ultrasonic testing scanner |
| CN104597138A (en) * | 2014-12-31 | 2015-05-06 | 钢研纳克检测技术有限公司 | Spiral guided wave electromagnetic ultrasonic transducer for detecting longitudinal and transverse defects of thin-wall steel pipe |
| CN105486399A (en) * | 2015-12-21 | 2016-04-13 | 中北大学 | Micro-capacitance ultrasonic transducer for distance measurement and imaging, and preparation method thereof |
| CN105445375A (en) * | 2015-12-31 | 2016-03-30 | 华南理工大学 | Handheld ultrasonic guided-wave structural damage detection device and detection method using same |
| CN107037127A (en) * | 2017-04-01 | 2017-08-11 | 西南石油大学 | A kind of complex probe formula underwater robot weld defect detection means |
| CN109115872A (en) * | 2017-06-22 | 2019-01-01 | 航天特种材料及工艺技术研究所 | A kind of supersonic detection method of bonding quality |
| CN109085241A (en) * | 2018-08-10 | 2018-12-25 | 扬州市紫麓信息技术有限公司 | Special vehicle transmission shaft damage detection apparatus and damage detecting method |
| CN109254080A (en) * | 2018-10-10 | 2019-01-22 | 南京佳业检测工程有限公司 | A kind of stainless steel ultrasonic detection device |
| CN209821134U (en) * | 2019-03-03 | 2019-12-20 | 上海九捷精密机械科技有限公司 | Multifunctional test positioning jig |
| CN110018241A (en) * | 2019-05-05 | 2019-07-16 | 广东省特种设备检测研究院（广东省特种设备事故调查中心） | The detection method of large thick-wall container welding point defect based on ultrasonic phase array |
| CN110292397A (en) * | 2019-06-19 | 2019-10-01 | 南京信息职业技术学院 | Chuck device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111855806A (en) | 2020-10-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111855806B (en) | Ultrasonic detection method for brazing of generator bridging strands | |
| EP1918701A1 (en) | Ultrasonic flaw detection method and method of producing seamless tube | |
| GB2440959A (en) | An apparatus for inspecting a rotationally symmetrical component | |
| CN111796023A (en) | Manual scanning device with guide rail, phased array ultrasonic detection method and system | |
| CN111650276A (en) | Automatic scanning device with guide rail, phased array ultrasonic detection method and system | |
| CN110596252A (en) | Steel construction welding seam ultrasonic detection equipment | |
| CN102841142A (en) | Weld joint detecting method based on ultrasonic detection device | |
| CN111796022A (en) | Guide-rail-free manual scanning device, phased array ultrasonic detection method and system | |
| CN112379001A (en) | Process method for reducing detection blind area of railway bearing ring by ultrasonic flaw detection | |
| CN111551632A (en) | Automatic scanning device with guide rail and sucker, phased array ultrasonic detection method and system | |
| CN111174894B (en) | Laser ultrasonic transverse wave sound velocity measurement method | |
| CN101639462A (en) | Method for detecting targets | |
| Pugalendhi et al. | Use of Phased Array Ultrasonic Testing (PAUT) & Time Of Flight Diffraction (TOFD) in Lieu of Radiography Testing on ASME U Stamp Pressure Vessel fabrication Projects | |
| Matsuida et al. | In-process monitoring of welding quality by robotic laser ultrasonic measurement system using microchip laser | |
| CN206074525U (en) | A kind of ultrasonic phased array imaging detection means towards aluminum alloy stirring friction welding part | |
| CN208795700U (en) | A kind of composite weld ultrasonic wave adjustment test block | |
| Kumar | Weld quality analysis of TIG, laser and electron beam welded SS 304 and 316 materials with NDT techniques | |
| KR102232470B1 (en) | A flaw detector with angle adjustment | |
| JPH09145696A (en) | Method and apparatus for measuring depth of flaw | |
| SRIVASTAVA et al. | Automated ultrasonic immersion through-transmission imaging technique–a novel way to evaluate dissimilar metal joints | |
| Bond et al. | Ultrasonic imaging and sizing | |
| Bond | Basic inspection methods (Pulse-echo and transmission methods) | |
| CN218567265U (en) | Device for detecting transverse cracks of welding line | |
| KR100901003B1 (en) | Penetration-depth adjustable send-receiver type eddy current test probe | |
| Carlson et al. | Laser sound generation in a weld pool |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |