SU794488A1 - Welding quality control device - Google Patents

Description

one

The invention relates to the field of non-destructive testing by the method of acoustic emission and can be used to identify microcracks during the welding process.

A device for recording cracking processes is known, comprising a transducer, a signal path, a noise suppression unit, and a delay line 1.

The drawback of the device is the low reliability of the control due to the weak selection of the useful signal against the background of interference.

The closest technical solution to the invention is a device for controlling the quality of welding, containing two electroacoustic transducers connected in series with amplifiers, a time interval meter and a pulse normalizer connected between the amplifiers and the time interval meter 2.

A disadvantage of the known device is the low reliability of the control, since it is not protected from impulse noise, and in addition, the device produces a complex algorithm for processing the results, which results in performance.

The purpose of the invention is to increase the reliability and performance of the control.

The unallocated goal is achieved by the fact that the device is equipped with a series-connected crystal oscillator, the output of which is connected to the input of the time interval meter, a control unit, the second output of which is connected to the input of the pulse normalizer, a storage unit, the second input of which is connected to the output of the time interval meter, a decoder the input of which is connected to the third output of the control unit, the information output unit, the second input of which is connected to the fourth output of the control unit, and numbers vym indicator and control unit, connected in parallel meter slot and connected to the output of the pulse normalizer.

The drawing shows a block diagram of the proposed device.

The device contains two electroacoustic transducers 1 and 2 connected in series with amplifiers 3 and 4, a time interval meter 5 and a normalizer 6 pulses connected between amplifiers 3, 4 and a time interval meter 5.

In addition, the device contains it sequentially connected crystal oscillator 7, the output of which is connected to the input

time interval meter 5, control unit 8, the second output of which is connected to the pulse normalizer 6 input, storage unit 9, the second input of which is connected to the time interval meter 5 output, decoder 10, the second input of which is connected to the third output of control block 8, block 11 output information, the second input of which is connected to the fourth output of the control unit 8, and digital indicator 12. In parallel with the time interval meter 5, the control unit 13 is turned on, the input of which is connected to the output of the normalizer 6.

The device works as follows.

The acoustic emission signals converted by electroacoustic transducers 1 and 2 into proportional electrical signals are amplified by the amplifiers 3 and 4, the signal from which is fed to the normalizer 6, where they are further amplified, separated from the noise, filtered by frequency, and selected by the envelope.

The signals from the output of the normalizer 6 are sent to a control unit 13, in which amplitude analysis of the received signals is performed, issuing a command to enable the next operation cycle after the reverberation stops from an acoustic emission pulse. The amplitude-normalized pulses from the output of the normalizer 6 also go to the meter 5 of the time interval, where they are normalized in duration and form the time interval of the difference in signal arrival to the converter 2 relative to the converter 1.

The impulse from the electroacoustic converter 1 opens the time selector of the time interval meter 5, whose counter begins to fill with the clock frequency from the output of the crystal oscillator 7. With the arrival of the second pulse from the electroacoustic converter 2, the time interval meter 5 closes and the pulse count stops. Information from the output of the meter 5 is recorded in one of the memory cells of the storage unit 9 when available from the control unit 13 in which the received signals were analyzed. The pulse from the second electroacoustic converter, normalized in amplitude and duration, sets the new address in the memory of the second block through the delay line. The same pulse sets the counter of the meter 5 to the zero state after the time set by the next delay line

and sends a signal to the control unit 13 about the end of the measurement cycle.

The control unit 8 sequentially records and reads information from the memory cells of the storage unit 9, controls the operation of the decoder 10, divides the clock, frequency to the values necessary for the operation of the device and sets the algorithm for the operation of the information output unit 11. The signal from the output of the storage unit 9 is fed to the decoder 10, from which the information about the coordinate of the defect and the amount of registered events is output to the information output unit 11. From the output of block 11, the information enters the digital indicator 12.

The use of new units in the device for controlling the quality of welding allows continuous monitoring of the quality of welded joints, eliminates the need for complex mathematical processing and ensures the selection of the useful signal in the lobby of interference.

Claims (2)

1. USSR author's certificate number 389454, cl. G 01N 29/04, 1971. 2. The patent of France No. 2164031, cl. G 01N 29/04 (prototype).