The principle of a digital ultrasonic flaw detector

1. Ultrasonic flaw detection is a kind of non-destructive testing, which refers to a testing method that uses ultrasonic flaw detector to check the surface and internal quality of the inspected parts without damaging the working state of the workpiece or raw materials.

2. There are many kinds of flaw detectors, but in the actual flaw detection process, pulse reflection ultrasonic flaw detectors are the most widely used. Generally in a homogeneous material, the existence of defects will cause the discontinuity of the material, and this discontinuity often causes the inconsistency of the acoustic impedance, we know from the reflection theorem that the ultrasonic wave will be reflected at the interface of two different acoustic impedance media, and the size of the reflected energy is related to the difference in the acoustic impedance of the medium on both sides of the interface and the orientation and size of the interface. Pulse-reflective ultrasonic flaw detectors are designed according to this principle.

Ultrasonic flaw detection instrument is a set of advanced technology as one of the detection instruments, it plays a very important role in the process of the hospital, and can also be used for fast and accurate inspection of parts, so as to achieve the purpose of safety. Compared with other detectors, ultrasonic detectors can complete the operation in a short time, and it is relatively simple to use, and the accuracy and sensitivity are also incomparable with similar products.

(1) The working principle of ultrasonic flaw detection instrument

As the name suggests, ultrasonic flaw detection instruments mainly rely on the unique properties of ultrasonic to achieve flaw detection, of course, this is mainly because ultrasonic has a variety of wave types and is suitable for a variety of propagation media.

When in use, its shear wave can accurately monitor the pipe, especially those cracks, scratches and porosity. Its longitudinal wave can quickly detect metal ingots, blanks, large forgings, etc., especially those white spots and delamination. However, its plate wave can detect the normal condition of the thin plate, unlike the surface wave, which can only detect the defects of some castings with relatively simple shapes.

Therefore, ultrasonic flaw detection instruments can help people's work very well when they are used.

(2) Advantages of ultrasonic flaw detection instruments

Because ultrasonic waves are used for detection, this flaw detector has a relatively high penetrating power, and it can even detect conditions below several meters when working. And its sensitivity is also very good, when in use, it can find reflectors that other detectors cannot find in a short time, and can accurately confirm the orientation, shape and size of the substance, and it can quickly respond to the detected results. Compared with similar products, it only needs to be measured from one side of the measured object when it is used, which saves manpower and time to a great extent, and its size is relatively small and easy to carry, and it is not only relatively simple to operate, but also has a very good safety performance.

(3) Deficiencies of ultrasonic flaw detection instruments

At present, ultrasonic flaw detection instruments are not accurate enough to inspect irregularly shaped or heterogeneous materials, and they are not suitable for the measurement of structures with cavities.

In summary, it can be seen that although there are certain deficiencies in the ultrasonic flaw detection instrument, its overall performance is still very good. And it plays a very important role in industry, water conservancy engineering, medical equipment, rescue equipment, etc., for people, the use of wave flaw detector can experience and improve accuracy in a large range of limb bending, and also saves a lot of manpower, is a good choice in the actual operation process.

You can get it for free

Digital ultrasonic flaw detector operation steps: 1. Turn on.

Second, look at the workpiece and choose the appropriate probe. Edition.

3. Open the pre-right saving channel.

Fourth, set the sound interval.

5. Adjust the gain.

6. [Quantitative] - freeze the current screen, press [+] to move back) or [—] forward) to move the yellow cursor (yellow dot) to the top of the defect wave, and the SA value is the position of the defect wave. Press [Quantitative] again

1 resume acquisition.

Seven, [backspace] - for delete.

Eighth, [Enter] - for OK.

9. [Return] - to return to the previous menu.

10. [Input Method] - For input uppercase and lowercase letters, the file name of the saved waveform data needs letters.

Eleven, [sa] distance [xa] level [ya] depth.

Amplitude a] height of the red wave [ RLA ] defect equivalent value or defect DB value.

Generally ultra-acoustic flaw detector source.

There will be instructions, you can read the instructions bai

Book. The general operation steps are as follows:

1. After connecting the instrument and the probe DAO, turn on the main power switch of the flaw detector and press the operation button to set the status of the system.

2. Press the operation key to preset the year, month, and day.

3. Enter the channel preset channel, select the flaw detection method and probe type, and enter the nominal value of the size of the probe element (the leading distance should also be entered for the oblique probe).

4. Place the probe on the CSK-IA test block and adjust the "gain" button of the instrument.

5. Measure or use the "zero" key to preset the zero offset of the probe.

6. Measure or use the "speed of sound" key to preset the speed of sound wave propagation in the workpiece (speed of sound).

7. When using the angle probe, you need to use the "K value" key to preset the K value.

8. Select the scale definition and size of the instrument with the "sound path" key.

9. When surface compensation is required, use the "compensation" button to compensate.

10. After the setting is over, press the "Function" button to enter the working state.

11. Coat the couplant on the surface of the measured workpiece, place the probe on the tested workpiece, move the probe to check whether the workpiece has defects, and freeze the found defects with the "quantitative" key and record them with the "record" key.

12. Record the defects detected.

13. After the detection is completed, turn off the main power switch of the instrument, remove the probe, wipe off the oil stain on the surface of the instrument and the probe and put it into the instrument box.

Surely it's plugged in? Then follow the switch to enter the body is the wound for detection, if there are impurities in the purchase, he can call the police.

The digital BAI ultrasonic flaw detector can quickly and conveniently, non-destructively and accurately detect, locate, evaluate and diagnose a variety of defects in the workpiece, such as cracks, welds, porosity, trachoma, inclusions, folding, etc., and is widely used in electric power, petrochemical, boiler and pressure vessels, steel structure, military industry, aerospace, railway transportation, automobiles, machinery and other fields. It is a must-have instrument in the non-destructive testing industry.

First of all, the power should be turned on, and then the measured item should be placed in front of the instrument and the switch should be pressed.

The operation steps of digital ultrasound in business are to first check his basic condition.

The ultrasonic flaw detector will send a high-frequency pulse electrical signal to the piezoelectric element of the probe, and the reverse piezoelectric effect will cause the element to produce elastic deformation, resulting in ultrasonic waves; After coupling, the ultrasonic wave is passed into the probed workpiece (insulator), and it is reflected when it encounters a heterogeneous interface, and the reflected ultrasonic wave will also act on the probe, and the electrical signal is generated for analysis due to the effect of positive piezoelectricity, and the defects can be known. This is also known as "flaw detection".

The role of the standard test block:

Flaw detector performance can be tested and verified.

Adjust the scanning speed to determine the location of defects.

Adjust the sensitivity.

Measure material falloff.

Determine the coupling compensation.

Insulator flaw detection itself is a very cumbersome work, it is easy to make the tester feel a little troublesome, and the operation is not easy to master, but in the whole transmission line, the insulator is a very important part, and its performance is also related to the normal operation of the entire power grid. Therefore, it is necessary to regularly test the insulator to avoid major transmission accidents. With a little practice, it is easy to master operations such as the DAC curve.

The YL-mut principle is that the pulse-reflection ultrasonic wave will be reflected at the interface of two media with different acoustic impedance, and the magnitude of the reflected energy is related to the difference of the acoustic impedance of the medium on both sides of the interface and the orientation and size of the interface, reflecting the nature of the defect. Vertical linearity error, horizontal linearity error resolution 40db.

Let's talk about the principle of ultrasound first, because the frequency of ultrasonic is higher than 20000Hz mechanical wave, it has high energy, and penetration, and a certain directivity, and has the characteristics of refraction reflection and waveform conversion! Therefore, ultrasonic waves have the ability to penetrate thick workpieces and encounter heterogeneous interfaces to produce reflections.

Pulse reflection is due to the inverse piezoelectric effect generated by the pressure element of the ultrasonic probe, which emits pulse waves with a higher frequency!

Ultrasonic flaw detector purchase skills.

Among the many series of flaw detectors, ultrasonic flaw detectors are the most popular. Because the ultrasonic flaw detector can be convenient, fast, accurate and non-damaging to detect, locate, evaluate and diagnose a variety of defects inside the workpiece. It can be used both in the engineering field and in the laboratory.

Therefore, ultrasonic flaw detectors have been used in electric power, chemical industry, petroleum, aerospace, aviation and other fields.

Because the ultrasonic flaw detector is a very professional instrument, not a professional, can not understand this kind of instrument at all, so many counterfeiters exploit the loopholes. Some domestic manufacturers use the characteristics of digital ultrasonic flaw detection to produce substandard products on a large scale.

If you don't have professional testing tools, the following ultrasonic flaw detector purchase strategy can help you identify the authenticity:

1. **Very low, you should understand the ultrasonic flaw detector market**, see if it is the right price, don't blindly covet cheap, the so-called cheap is not good.

2. See whether the vertical linearity is qualified and the method.

3. There are also some indicators that require special test blocks. It is recommended that the new instrument be sent to the provincial metrology and testing institute for identification to avoid being deceived.

4. In the state of not connecting the probe, adjust the gain to the maximum, and the waveform on the screen cannot exceed 10% of the screen, if it exceeds, the instrument is unqualified.

5.Pay attention to the production process and certification documents, generally ultrasonic requires professional training.

The consequences of using an unqualified ultrasonic flaw detector are more serious. Since ultrasonic non-destructive testing is used in quality testing or safety testing, if a quality accident occurs or even endangers personal safety, the unqualified instrument you buy back with a little money will cause you to be in a very unfavorable situation.

It is hereby suggested that you should not just look at the advertisement, exaggerate, greedy for a temporary cheap, to seek truth from facts to buy qualified flaw detectors, responsible for quality is equivalent to being responsible for yourself.

Haha, I recommend your home first, tiem17 hehehe, what do you do, what do I want.

Now the domestic ultrasonic flaw detector is taken ancient software, the response effect in the system is poor, Beijing Jitai Ke instrument testing equipment **** production of jut800 type, the use of foreign advanced software, operation one-button calibration, unlimited time video, high-end appearance design, mainly used for special inspection institutions, the operation is fast, convenient and accurate, the design chief engineer hired German professional technology.