SU1385054A1 - Method and device for pulsed eddy current testing - Google Patents

Abstract

The invention relates to non-destructive testing and dp measurements of the physicomechanical parameters of electrically conductive non-ferromagnetic objects can be used. Taller. Control performance is achieved by automatically generating signal parameters at a nodal point by comparing the signals of two identical eddy current transducers. In addition, by measuring the time coordinate of the nodal point, the functional features are expanded. Eddy current transducers 3 and 4 are installed above the surface of the test object with different gaps and powered by the same current from the pulse generator 2. The node point is determined at the time of coincidence of the stresses, which is fixed by the comparison unit 5. 2 sec. and 1 z. p. f-ly, 2 ill. with o (L

Description

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The invention relates to non-destructive testing and can be used to measure the physicomechanical parameters of electrically conductive non-ferromagnetic objects.

The purpose of the invention is to monitor the productivity by automatically obtaining parameters.

Eddy current transducers 3 and 4 are installed above the surface of a controlled object with different gaps, P1 pulses Uj (FIG. 2) of rectangular form from generator 2 pulses are fed to the inputs of eddy current transducers 3 and 4, Signals U, and U from the outputs of eddy current transforms

signal at the nodal point by comparing JQ bodies 3 and 4, respectively, comparing the signals of two identical eddy current transducers, as well as expanding the functional capabilities of TX by measuring the time coordinate of the nodal point.

Fig. 1 is a block diagram of a device for pulsed eddy current testing; Fig, 2 - voltage diagrams, due to the operation of the device

The device for a pulsed vortex T01LEWO control consists of a reference frequency generator 1, a pulse generator 2, identical eddy current probes 3 and 4 connected by inputs to a pulse generator 2, a comparison unit 5 connected by inputs to the outputs of eddy current transformers 3 and 4, triggers 6-8 , coincidence circuit 9, voltage measuring unit 10 connected by the first input to the output of the eddy current converter 3 and the second input to the trigger output 7, pulse counter I1 connected by the counting input to the output of circuit 9 Eni, and the Start button (not shown) connected to the setup input of trigger 6, the reset inputs of trigger 7 and 8,

counter M pulses and the unit 10 voltage measurement measures the amp-

voltage is triggered, trigger 6 is connected via an output to info.rmakshonny trigger input 8, trigger output 7 is connected to the second input of voltage measuring unit 10, inverse output of trigger 7 is connected to reset input of trigger fi and the first input of coincidence circuit 9, trigger output 8 is connected with the second input of the circuit 9 coincidence and with the information input of the trigger 7, the synchronization input of which is connected to the output of the comparison unit, the synchronization input of the trigger 8 is connected to the pulse generator 2, and the third input cxeMi i 9 coincidence is connected to the generator 1 of the reference Oh frequency ,.

The method using a pulsed eddy current control device is implemented in a very competitive manner.

The voltage values corresponding to the nodal point. The time coordinate of the nodal point will be equal to

45

. ,, N 1,

Knot point physically

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determined by the intersection of transient diagrams at the output of eddy current transducers 3 and 4, the voltage amplitude and temporal coordinate b carry an independent information and can be used to measure two parameters of the test object, for example, the plate thickness and fe conductivity.

Claims (2)

Invention Formula 1, A pulsed eddy current control method. A comparison unit 5, and at the moments of their equality, a voltage pulse U appears at the output of the comparison unit 5. When you press the Start button the pulse by the leading edge sets the triggers 7 and 8 (and, Uj) to the zero state, the voltage measuring block 10 and the pulse counter 11, and the falling edge sets the trigger 6 in the unit state (U.), the back front of the excitation pulse of the generator 2 pulses sets the trigger 8 in the unit state (Uj), and resolving the potential from its output enters the input of circuit 9 coincidence. At the counting input of the counter 11 pulses, counting pulses start to arrive: and the generator 1 of the reference frequency, next with the frequency f ,,, When comparing the voltages at the outputs of eddy current transducers 3 and 4, a single signal appears at the output of the comparison unit 5 sets the trigger 7 to one — the Hoti state; the coincidence circuit 9 closes and the number of pulses in the counter 11 pulses is fixed; N With the arrival of a single signal from the output of the trigger 7, the measurement unit 10 The voltage values corresponding to the nodal point. The time coordinate of the nodal point will be equal to . ,, N 1, Knot point physically determined by the intersection of transient diagrams at the output of eddy current transducers 3 and 4, the voltage amplitude and temporal coordinate b carry an independent information and can be used to measure two parameters of the test object, for example, the plate thickness and fe conductivity. Invention Formula 1, A pulsed eddy current control method. that the eddy current transducer is excited over the surface of the monitored object with a given gap, excitement eddy currents are generated in the controlled object, and the node point corresponding to the gap variation is obtained on the transient diagram, the amplitude of the eddy current signal is measured at the time point corresponding to the node point, and, from the measured amplitude, a parameter of the monitored object is determined, characterized in that, in order to increase the productivity, a surface is set above controlled object with a gap other than the predetermined second eddy current transducer identical to the first, both the converter feed the same current, compared signals eddy current probes and determining an anchor point in equal signal amplitudes, 2. Method non.l, characterized in that, in order to expand the functionality, the time coordinate of the nodal point is measured and the measured value is used to determine the second parameter of the object to be monitored, 3, A device for pulse eddy current control, containing a series-connected generator pulses, an electromagnetic transducer and a voltage measuring unit, as well as a comparator unit, which is equipped with a second identical first electromagnetic transducer, included between the generator output pulse G COB and the second input of the comparator unit, a generator reference frequency, three triggers, a coincidence circuit, a pulse counter connected by a counting input to the output of the coincidence circuit, and a Start button connected to the setup input of the first trigger, the fault inputs of the second trigger, the third a trigger, a pulse counter and a voltage measuring unit; the first trigger is connected to the information input of the third trigger; the output of the second trigger is connected to the second input of the voltage measuring unit; the inverse output of the second trigger is connected to the first input of the coincident input, the output of the third trigger the trigger is connected to the second input of the co. and with the information input of the second trigger, the synchronization input of which is connected to the output of the comparison unit, the synchronization input of the third trigger is connected to the pulse generator, and the third input of the coincidence circuit is connected to the reference frequency generator. and eleven -If Phie, 2