SU1580242A1 - Apparatus for measuring magnetizing conditions of magnetic flaw detector - Google Patents

Abstract

The invention relates to non-destructive testing and can be used to measure variable, constant (rectified) and impulse currents when the product is magnetized during the control process. The aim of the invention is to improve the measurement accuracy, which is achieved by eliminating the influence of industrial interference and ambient temperatures on the values of the measured parameter. In the device, the transducer 1 is made in the form of two inductor coils placed symmetrically from two sides on the power bus of the flaw detector. The signals taken from the coils through the integrating amplifier 21, the linear detectors 2, 3, the adder 4, the integrator 5 and the switch 6 arrive at the indicator 7, where the measured magnetizing current is read. Matching amplifiers 14, 12, differentiator 9, comparators 10, 15, electronic switches 11, 13, storage capacitors 16, 17, and indicator 7 are used to measure the amplitude values of the currents. The time setting indicator 22 serves to limit the display time of the amplitude value of the measured current. 2 Il.

Description

a sum signal of one polarity, which is fed to the input of the integrator 5, the differentiator 9 and the time setting unit 22.

To measure the effective values of constant (rectified) and alternating currents, the summed signal from the output of adder 4 is fed to the input of integrator 5. The summed and integrated signal through switch 6 (effective position) is visualized by indicator 7. The latter reads the effective value of the variable, constant, rectified and impulse currents.

measured currents flowing through the second matching amplifier 14 to the indicator 7. On the scale of the latter, the value of the measured magnetizing current is read. In the case of measuring rectified or pulsed currents carrying a unipolar signal of positive or negative polarity, the operation of the device is similar to that considered, but the signal from the converter 1 and integrating the amplifier 21 passes through only one of the detectors 2 or 3

ten

To eliminate errors in measuring the iHoro amplitude of the current value due to leakage currents in capacitors 16 and 17. For measuring the amplitude values of 20, the generator 22 is used to measure the time of different types of currents of different types of switch b tox. The setting unit 22 limits the Amplitude position, the time of the value indication and the MSR. This indicator 7 is connected to the output current. The time setting unit 22 starts working with the second matching amplifier 14, the signal from the adder 4 enters 25 melting of the signal from the output of the adder 4, the input of the differentiator 9, At its output After the disappearance of the signal at the output

measured currents flowing through the second matching amplifier 14 to the indicator 7. On the scale of the latter, the value of the measured magnetizing current is read. In the case of measuring rectified or pulsed currents carrying a unipolar signal of positive or negative polarity, the operation of the device is similar to that considered, but the signal from the converter 1 and the integrated amplifier 21 passes through only one of the detectors 2 or 3.

a voltage appears proportional to the first derivative of the measured current module. This signal is fed to the comparators 10 and 15, at the outputs of which, respectively, square-shaped signals are formed. The pulsed rectangular signal with its leading edge includes an electronic key 11, which connects the storage capacitor 16 to the output of the adder 4 ". The capacitance 16 is charged to a voltage equal to the amplitude value of the output signal of the adder 4. The rear edge of the comparator's 10 square pulse coincides in time with reaching the maximum voltage of the signal of the adder 4, closes the key 11. At the same time, the second electronic key 13 opens with a pulse from the output of the second comparator 15 by connecting the second capacitor 17 through the amplifier 12 to the capacitor 16, charged up to a voltage equal to the amplitude of the signal received at the output of the adder 4. At the end of the measured signal (pulse) received from the output of the adder 4, the second electronic switch 13 is closed and the capacitance 17 remains charged until am30

35

40

45

50

adder 4 after a predetermined period of time at the output of the setpoint adjuster 22, the indication produced a signal in the form of a pulse arriving at the electronic switches 11 and 13, which, opening, allow to discharge the capacitors 16 and 17 and thereby set the indicator 7 to the zero position .

The proposed device will make it possible to more accurately determine the magnetization mode in the control of magpito products using a powder method using various types of currents, namely, alternating, constant, rectified, and pulsed.

Measurement of magnetizing currents can be carried out in amplitude or effective values. Measuring pulsed currents in amplitude values is essential when testing products on residual magnetization and with a large demagnetizing factor. Measuring the effective current value will allow you to more accurately determine the magnetization regimes in the control in the proposed magnetic field. The device will also increase the reliability of control by eliminating the influence on the measurements of the magnetizing currents of industrial

the magnitude of the voltage of the signal-55 mech and temperature fluctuations around the output of the adder 4, the use of two storage tanks 16 and 17 allows to form a voltage

environment.

Claims (1)

Claim Device 0 five 0 five 0 The adder 4 after a predetermined period of time at the output of the time indicator adjuster 22 has generated a signal in the form of a pulse arriving at the electronic keys 11 and 13, which, opening, allow the tanks 16 and 17 to discharge and thus set the indicator 7 to the zero position. The proposed device will make it possible to more accurately determine the magnetization mode in the control of products using the magpite-powder method using various types of currents, namely alternating, constant, rectified and pulsed. Measurement of magnetizing currents can be carried out in amplitude or effective values. Measurement of pulsed currents in amplitude values is essential when testing products on residual magnetization and with a large demagnetizing factor. Measuring the effective current value will allow you to more accurately determine the mode of magnetization under control in the proposed magnetic field. The device will also increase the reliability of control by eliminating the influence of measurements of magnetization currents of industrial fields and temperature fluctuations around fur and temperature fluctuations around- environment. Claim Device magnetizing a magnetic flaw detector containing a transducer, two linear detectors, an adder, the direct and inverse inputs of which are connected to the outputs of the linear detectors, an integrator connected in series, a measurement mode switch and an indicator, and an amplitude current measurement unit, made in the form of a series-connected differentiator connected the input to the output of the adder, the first comparator, the first electronic key, - the second vhbd of which is connected to the output of the adder, the first matching of the amplifier, the second electronic switch and the second matching amplifier output connected to the second input of the measuring switch mode, the second comparator having an input connected to the output of the differentiator, and the output - to the second input of the second elokt I sh S 4, / hell Ш.2 Compiled by A. Chernykh Editor N, Bobkova Tehred L. Serdyukova Proofreader T. Malets Order 2007 Circulation 516 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 five 0 The key contains two cumulative capacitances, each connected to the output of the corresponding key, characterized in that, in order to increase the measurement accuracy, the converter is made of two coils of inductance connected to each other in a counter symmetrically on both sides, and the device is equipped with an integrating amplifier, an input connected to the outputs of the inductor coils, and an output to the inputs of linear detectors, a time reference for indicating the amplitude value of the current, the input connected to the output of the adder, the first output to the third input of the primary key of the electronic key, the second output to the third input of the second electronic key, and the input of the integrator is connected to the output of the adder, / Subscription