SU715992A1 - Ultrasonic flaw detector - Google Patents

Description

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The invention relates to the field of non-destructive testing using an ultrasonic method and can be used to detect defects in manual and automatic testing.

Known ultrasonic flaw detector containing a probe pulse generator, amplifier, cascade. delays, sector, gating pulse generator and relay 1.

The disadvantage of it is the low reliability of the control.

The closest to the invention to the technical essence and the achieved result is an ultrasonic flaw detector containing serially connected synchronizer, probe pulse generator, receiving-transmitting transducer with sound guides and connected between the synchronizer and receiver receiving-transmitting device from the defect.

The disadvantage of it is the low reliability of the control.

The purpose of the invention. Owners, increase the reliability of control.

The goal is achieved by the fact that the flaw detector is equipped with a series-connected delay stage, the INPUT of which is connected to the synchronizer output by a generator of reference pulses, an adder, the second input of which is connected to the transmitter-transmitter transmitter, an electronic switch, the second input of which is connected to the output of the delay cascade, threshold cascade and indicator of acoustic contact.

The drawing shows the block diagram described flaw detector.

1 The ultrasonic flaw detector contains a synchronizer 1 connected in series, a generator of 2 probe pulses, a receiving and transmitting transducer 3 with sound conductors placed in a common case, a signal processing unit 4 from a defect connected between a synchronizer and a receiving and transmitting transducer, sequentially connected to a delay stage 5 whose input is connected to the output of the synchronizer, the generator 6 reference pulses adder 7 ,. whose second entrance

Q is connected to; emitter transceiver transducer, electronic switch 8, the second input of which is connected to the “jeH to the output of the delay stage, the threshold cascade of the dyna p lU aKykticheskogo Contact.

. The BLOCK 4 signal processing from the defect contains an amplifier 11, a cathode ray tube 12 and a sweep generator 13, the output of which is connected to the input of the cathode ray tube. Ultrasonic flaw detector works as follows.

The synchronizer 1 generates pulses, which are used to start the generator 2 probe pulses and the generator 13 sweep. The emitter of the transceiver 3 of the transducer 3 converts the emitter of the Rychic excitation pulse into the acoustic and through the sound duct and a thin layer, the acoustic contact маз lubricant sends it to the controlled Part, while part of the energy of the acoustic pulse is reflected from the end of the sound guide of the radiator receiving and transmitting. T. l to the input of the adder 7 receives a pulse of excitations of a radio pulse, reflected from the end of the duct of the radiator. The second input of the adder receives a radio frequency pulse of the generator b of reference pulses of the same frequency and duration, which is controlled from the output of the delay stage 5. The delay time is chosen so that the radio pulse of the geyator of the reference impulses coincides in time with the radio pulse reflected from the end of the acoustic circuit. The output of the adder 7 is fed to the electronic switch 8, controlled by a delay stage 5, in which the excitation pulse is suppressed and the total radio pulse is extracted.

Under the influence of the sum of the radio pulse, coming from the output of the electronic key, it works out of the switch / cascade 9 and turns on the indicator 10 of the acoustic contact. In the event that the medium with a lower acoustic / IMC resistance is bounded with the end of the sound duct, then the phase of the signal reflected from the end of the sound duct.

changes to, the amplitude of the sum signal at the output of the electronic 8 is reduced, and the threshold cascade 8 turns off the indicator, indicating that there is no automatic contact between the part being monitored and the receiving-transmitting converter. The acoustic impulse passed into the test piece is reflected from the defect, fed to the receiver of the transducer 3, converted into electrical, amplified by amplifier 11 and (fed to the input of the cathode ray tube 12, resulting in an impulse from the defect .

The described flaw detector makes it possible, with high reliability, to carry out the inspection of parts by determining the acoustic contact, in which 0 does not have a bottom signal.

Claims (2)

1. USSR author's certificate number 95975, cl. G 01 N 29/04, 1952. 2. Ermolov I. n. The physical basis of the echo and shadow methods of ultrasonic flaw detection, M., Ma19-21 (prototype)