1、超声波探伤英文资料Ultrasonic flaw detectionUltrasound is a mechanical wave, mechanical vibrations and fluctuations in the physical basis of ultrasonic testing.Reciprocating cyclic movement of an object along a straight line or curve in a near equilibrium position, known as the mechanical vibration. Propagati
2、on of vibration, known as volatility. Fluctuations into mechanical waves and electromagnetic waves two categories. Mechanical wave propagation of mechanical vibrations in an elastic medium. The ultrasound is a mechanical wave.The main parameters of the mechanical wave wavelength, frequency and wave
3、velocity. Wavelength : the distance between the same two adjacent oscillation phase of the same wave line particle known as the wavelength, source or medium, any one particle to complete a full vibration wave just forward a wavelength distance, commonly used in meters (m); frequency f: fluctuations
4、in the process, he served as a given point in one second, adopted by the number of complete wave is called frequency, commonly used in units of hertz (Hz); wave velocity C: fluctuations in the wave per unit time transmitted the distance is called the wave velocity, the common units of meters / secon
5、d (m / s).Wavelength and wave velocity is proportional to and inversely proportional to frequency; when the frequency is fixed, the wave velocity the greater the wavelength the more long; wave velocity when the frequency lower, the more long wavelength available by the above definition: C = * f.Sub-
6、sonic, sonic and ultrasonic mechanical wave propagation in an elastic medium, the propagation velocity in the same medium. Their difference mainly due to different frequencies. Frequency between 20 20000Hz can cause people to hearing the mechanical wave is called sound waves at frequencies below 20H
7、z mechanical waves known as infrasonic, frequencies above 20000Hz of mechanical waves called ultrasound. Infrasonic, ultrasound can not be heard.The frequency of the ultrasonic flaw detection is generally between 0.5 10MHz, the inspection of steel and other metal materials, commonly used frequency f
8、or 1 5MHz. Ultrasonic wavelength is very short, which determines the ultrasound has a number of important features, so that it can be widely used for nondestructive testing.Good direction:(1)Ultrasound is high frequency, very short wavelength mechanical wave, the wavelength used in the nondestructiv
9、e testing of millimeter; ultrasound like light waves has a good direction can be directed emission, easy to be found in the material was seized defects.(2)High energy: energy (sound) and is proportional to the square of frequency, ultrasonic energy is much larger than the energy of ordinary sound wa
10、ves.(3)In the interface reflection, refraction and wave conversion: ultrasonic on some of the features of the geometrical acoustics, such as a straight line in the medium, the case of interface reflection, refraction and wave conversion.(4)Penetrating power: when the ultrasonic wave propagation in m
11、ost media, the dissemination of energy loss is small, the propagation distance, ability to penetrate its ability to penetrate up to several meters in some metallic materials.Ultrasonic flaw detector is the frequency above 20kHz, beyond the people ears to distinguish between talented and penetrating
12、a strong sound waves. Is a portable industrial non-destructive flaw detector, it can be too fast, convenient, no damage to the workpiece internal variety of defects (welds, cracks, folding, loose sand holes, pores, adulterated, etc.), detect, locate, evaluate and diagnostics. Both can be used to car
13、ry out the room, can also be used for the project site. Commonly used in boilers, pressure vessels, aerospace,aviation, electric power, petroleum, chemical industry, offshore oil pipeline, military, shipbuilding, automobiles, machinery manufacturing, metallurgy, metal processing industries, steel st
14、ructures, rail transport, nuclear power, university and other industries.Ultrasonic flaw detector reason: the use of ultrasonic reflection truth nondestructive detection on the defects in the data, when the ultrasound to convey the information to be detected, data acoustic characteristics and the in
15、ternal organization of the inevitable impact of changes on ultrasonic communication, through ultrasound by affect the level and circumstances of the detection survey data features and skills of the tectonic shift known as ultrasonic testing.Color ultrasonic flaw detector LED display is colorful, mul
16、ti-color selection, or the premise of divergent light, backlight continuation adjustable, more intuitive to see.Thereare many about the use of the ultrasonic flaw detector, for example, the reflection of ultrasound to measure the interval, the application of high-power ultrasonic vibration to elimin
17、ate the scale attached to the boiler above, the application of high-energy ultrasound made the harmonic scalpel to get rid of crushing the human body cancer, stones, etc.The effect and the penetrating power of the ultrasonic flaw detector, the reflection of the application of ultrasound can be a str
18、aight line to convey the characteristics of the detection is a great use of areas. Ultrasonic flaw detection using the detection of primary cover various types of information in the industrial and medical testing and diagnosis on the human body, after which one can detect metals and other industrial
19、 information, there is no bubble, scars, cracks and other defects can be detected can normal people the bodys soft tissue, blood flow.People is how the sample application of ultrasound to detect?Ultrasonic flaw detector is currently mortal is the measured object (for example, industrial information,
20、 the human body) emission ultrasound, and then apply the reflection, Doppler effect, transmission to obtain the information inside the measured object and form images through the disposal. Ultrasonic flaw detector, the Doppler effect method is the application of ultrasound in the attack to encounter
21、 the object of activities of the Doppler shift effect to draw the characteristics of the activities of the objects bias and speed; transmission rule is parsed ultrasound to penetrate through measured object after the transformation to derive the internal features of objects, their use in the develop
22、ment stage; ultrasonic flaw detector, the first introductions is the way to the most frequently used reflection method to obtain the characteristic information of the object interior. The reflection method is based on ultrasound task after the onset of strong reflection of the differences between th
23、e acoustic impedance of tissue interface reason, as we know, sound waves from one medium to convey to a medium of hours of the interface between the two will be at the onset of reflection, and the greater the difference between the media reflected the greater will be, so we can launch an object pene
24、trating power, ultrasound can be a straight line to convey the ultrasonic flaw detector and the reflected ultrasonic accepted and this tissue contains various types of media big and small can be determined based on the status of the reflected ultrasound has amplitude ultrasound has spread status and
25、 a variety of media cf the difference in the level of information (a reflection back reflects the reflective interface from the detection of the appearanceof the interval, the magnitude may reflect the media big and small, mutatis mutandis, to the differences in level and other characteristics), ult
26、rasonic flaw detector and then discriminant of the measured object can have abnormal. The occurrence of touch to a good many in this process, including ultrasound, accepted flags signal of traffic lights and disposal. One of the ultrasonic approach is to encourage electric flags lights after the cir
27、cuit is passed to the piezoelectric effect of crystal (cristobalite, sulfuric acid, lithium, etc.), so that the vibration and ultrasonic; but to accept the reflected ultrasound after midnight, this pressure the transistor was the pressure of the reflected sound waves will occur electric flags lights
28、 and send a series of disposal to the disposal of flags lights circuit, ultrasonic flaw detector constitute the final image for people to look at discrimination.Here based on the image disposal methods (that is to get the flags lights converted to images in what way) the species can be divided into
29、A-type shows, M-type type B, type C, F-type display. A-type display is one of the ultrasound flags will be accepted lights disposal into a waveform image based on the shape of the waveform can be seen that the measured object which can have anomalies and deficiencies in the side, how much, ultrasoni
30、c flaw detector first used to industrial inspection; the M-type display is the one through the detection of luminance disposal according to work one by one opened constitute a one-dimensional space multi-event timing diagram, suitable to look at the internal active form objects, ultrasonic flaw dete
31、ctor, such as activities organs, arteries, etc. Type B shows a lot through the detection of luminance disposal group consisting of two-dimensional side-by-side, which reflects the objects internal fault section of the anatomical images (disease backyard use B super this is the reason to do it), ultr
32、asonic flaw detector is suitable to look internally at static objects; C-type F-type display with unmatched less. Ultrasonic flaw detection will not be very precise, and more convenient compared with other detection methods, fast, nor will it detect objects and operator risk, so were the people more
33、 and more throughout the farewell, has a very broad carried out prospects.The development of ultrasound and in the overhaul of the stateAbstract: In the various types of power plant equipment maintenance, service life assessment,the most frequent and widely used in ultrasonic testing technology. Ultrasonic flaw detection applications, applicability, hi
