SU1434359A1 - Apparatus for ultrasonic shadow inspection of articles - Google Patents

Description

The invention relates to non-destructive testing of products using an ultrasonic shadow method and can be used in determining the depth of defects in products.

The purpose of the invention is to improve accuracy by tracking the change in the distance between the emitting converters and the moving CONTROLLED product.

The drawing shows a block diagram of the proposed device.

The device contains emitting transducers 1 and 2 and receiving transducers 3 and 4, installed on p (-Circuit. Receiving transducer 3 | is connected through a serial coaxial amplifier 5 and recorder 6 (Defects to time generator 7, (to which another input is connected) Converter 4 through successively connected amplifier U and recorder 9 defects. The ICTBO device also contains in series Connected setting unit 10 speed v, Converter 11 pulses, the second | input of which is connected to the output of the converter 7, adder t2 and (indicator 13, additional receiving converters 14 and 15, intended to be installed in the same plane with radiating converters 1 and 2 parallel to the direction of movement of the test article 16, successively connected by the former | 17, the input connected to you | Go to the recorder 6 defects, the i18 element coincidence, the second input of which | is connected to the additional output: converter 14, time generator 19, multiplier 20, adder 21 and divider 22 whose output is connected to the second input Odmator 12. A serially connected formatter 23 whose input is connected to the output of the defect recorder 9, a coincidence element 24, a second input connected to the receiving converter 15, a time generator 25 and a multiplier 26, the output of which is connected to the second input of the adder 21. Generator 27 probe pulses connected to the radiating transducers 1 and 2 and the second inputs of the formers 19 and 25 time.

The device works as follows.

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The emitting transducers 1 and 2, excited by the probe-oscillating pulse generator 27, emit ultrasonic vibrations into the controlled article 16. Ultrasonic oscillations reflected from the surface of the test object closest to the radiating transducers are received by transducers 14 and 15 tuned to the maximum amplitude of the ultrasonic signal reflected from the surface. The ultrasonic vibrations that have passed through the product are received by the receiving transducers 3 and 4. The product, in the process of control, moves relative to the ultrasonic transducers at a speed V. Leys 3 and 4 are amplified by amplifiers 5 and 8 and fed to recorders 6 and 9 defects, made in the form of threshold devices that provide a comparison of the input signal with a threshold one. When the amplitude of the input signal exceeds the threshold value, a logical zero signal is generated at the output of the corresponding defect recorder. If the input signal does not exceed the threshold value in amplitude, a logical unit signal is generated at the output of the defect recorder.

When a defect is detected by the first pair of transducers 2 and 3, the first recorder 6 of defects generates at its output a signal of a logical unit that arrives at the input of the first shaper 17 of pulses and the first input of the first shaper 7 of time. With the arrival of this signal, the first pulse shaper 17 forms a control pulse at its output, steps to the second input of the amplifier element 18 coincidence. The latter passes a signal from its receiving transducer 14p to its first output to the first time driver 19. The second input of the time generator 19 is connected to the output of the generator 27 probe pulses. The time former 19 generates a signal at its output proportional to the time interval between the arrival of the second signalformer 19 for the signal from the generator 27 of probe 1 mp and the arrival of the signalformer for the output of the coincidence element 18. The signal from the time generator 19 is fed to the input of the multiplier 20, and a signal is generated at its output proportional to

and.

& t, -UCH ,,

Cosi,

it,

where r is the half angle between the directions of radiation of the radiating transducers; the delay time in the reception of the ultrasonic signal of the radiating transducer 2 by the receiving transducer 14, determined when a defect is detected by a pair of transducers 2 and 3; the rate of propagation of ultrasound in the medium between

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converters and product.

This signal is fed to the first input of the first adder 21.

When a defect is detected by a pair of transducers 1 and 4 of the second register — that is, the 9 defects generates at its output a signal of a logical unit, which chairs the input of the second pulse generator 23 and the second input of the time generator 7. The first time generator 7 forms the time interval t between the moments of defect detection by a pair of converters 2 and 3 and a pair of converters 1 and 4. Using the pulse converter 11, this time interval is converted into a signal Uj proportional to the distance from the point of intersection of the radiation directions of the converters before defect:

and 2

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This signal arrives at the first;

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defect pair converters 1 and

4, simultaneously with the pulse generator described above, the signal from the defect recorder 9 generates a control pulse at its output that arrives at the second input of the coincidence element 24, which passes a signal from the receiving converter 15 to its output, which is fed to the first input of the time generator 25. The second input of the imaging unit - 25 times connected to the output of the generator 27 probe pulses. The time generator 25 generates at its output a signal proportional to the time interval between the arrival of the signal from the generator 27 from the pulse generator to the second input and the arrival of the signal from the output of the matching element 24 on the first input of the driver 25. The signal from the output of time maker 25 is fed to the input of multiplier 26, and then a signal is generated at its output proportional to

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& t. V

Vi.

Cosol

where ut is the delay time in reception

ultrasonic signal emitting transducer 1 receiving transducer 15, determined when a defect is detected by a pair of transducers 1 and 4.

This signal arrives at the second input of the adder 21. At the same time, the output of the adder 21 generates a signal proportional to the value that enters the input of the divider 22. The divider 22 determines the value of / 2114 .. The adder 12 determines the exact depth of the defect.

Claims (1)

DEVICE FOR ULTRASONIC SHADOW CONTROL OF PRODUCTS, containing a generator of probing im-; pulses, two measurement channels, each of which consists of sequentially electro-acoustic connected radiating transducer connected to the output of the probe generator. pulses, a receiving transducer, an amplifier, and a defect recorder connected in series to a speed indicator and a speed controller, the output of which is connected to the second input of the pulse converter, excluding _; her. the fact that, in order to improve accuracy, it is equipped with two additional receiving transducers, two electric circuits from a series formerly Shaper connected to the corresponding defect registrar, a matching element, the second input of which is connected to the output of the corresponding additional receiving converter, additional time shaper, the second input which is connected to the output of the probe pulse generator, and the multiplier and connected in series with the first adder, the input which are connected to the outputs of the multipliers, the divider and the second adder, the second 1434359 A1