SU1599757A1 - Method and apparatus for non-destructive inspection by means of higher harmonics - Google Patents

Abstract

This invention relates to a non-destructive testing technique. The aim of the invention is to improve the accuracy of control of physical and mechanical properties of ferromagnetic products. The information signal taken from the transducer measuring coil is detected, the negative or positive half-wave is inverted and summed with the positive or negative half-wave information signal and the even harmonic is extracted from the resulting signal. A device for implementing the method comprises a series-connected adjustable sinusoidal current generator, a pass-through converter with field-building and a measuring coil, a linear detector with two outputs of unipolar signals, an inverter whose input is connected to one of the outputs of a linear detector, an adder whose inputs are connected respectively to the second output linear detector and the output of the inverter, and the output is connected to a selective amplifier, and measuring amplitude values. 2 s. 1.z.p.f-ly, 1 ill.

Description

one

(21) 4468295 / 25-28

(22) 08/01/88

(46) 15. 10.90, Bull. K 38

(71) Institute of Applied Physics of the Academy of Sciences of the BSSR

(72) N.N., Zatsepin and B.DLPaporov

(53) 620.179.14 (088.8)

(56) Defectoscopy, 1976, No. 6, p. 53-57.

I

(54) METHOD OF NON-DISTRIBUTED CONTROL BY THE METHOD OF HIGHER HARMONICS AND DEVICE FOR. HIM. IMPLEMENTATION

(57) The invention relates to a non-destructive testing technique. The aim of the invention is to improve the accuracy of the control of physical and mechanical properties of ferromagnetic products. The information signal taken from the transducer measuring coil is detected, the negative or positive half-wave is inverted and summed with the positive or negative half-wave information signal and the even harmonic is extracted from the resulting signal. A device for carrying out the method comprises a series-connected adjustable sinusoidal current generator, a pass-through transducer with field creation and a measuring coil, a linear detector with two outputs of unipolar signals, an inverter whose input is connected to one of the outputs of a linear detector, an adder whose inputs are connected respectively to the second output linear detector and the inverter output, and the output is connected to a selective amplifier and an amplitude value meter. 2 sec. 1 з, According to f-ly, 1 ill.

SL

This invention relates to a technique for non-destructive testing of products and can be used for monitoring. physical and mechanical properties of ferromagnetic materials.

The purpose of the invention is to increase the accuracy of controlling the physicomechanical properties of ferromagnetic products due to the magnetization of the controlled ferromagnetic product only by a variable sinusoidal magnetic field.

The drawing shows a block diagram of a device for controlling the physicomechanical properties of ferromagnetic products by the method of higher harmonics.

The device contains a pass-through converter 1, an adjustable oscillator 2 of sinusoidal current, a linear detector 3 with two outputs of unipolar signals, an adder 5, a selective amplifier 6, a meter 7 of amplitude values. .

The device works as follows.

The signal taken from the transducer measuring coil 1 is sent by

(;about

S3

A linear detector 2, in which it is detected, is then inverted or negative, the half-wave signal is inverted to the INV (2p-tor.4 and fed to the input of the adder 5., to the second input of which a signal is fed from the second output of the linear detector 3 ' Thus, bipolar-2. The method according to p. 1, of which is a second signal from the measurement coil of the formational transducer 1 is converted into a single-field signal The output from the output of the adder 5 is fed to a measuring amplifier 6, in which the second harmonic is emitted, the magnitude of which is measured by meter 7,

Claims (2)

1. A method of non-destructive testing using the method of higher harmonics, which means that a controlled ferromagnetic product is affected by a sinusoidal magnetic field, measured using a transient electromagnetic transducer, the voltage introduced by the product is extracted from it by a harmonic, its amplitude is measured and its magnitude is determined a controllable parameter, characterized in that, in order to increase the control accuracy, before the signal is monitored. 3c Device for non-destructive testing using the method of higher harmonics, containing series-connected t5 adjustable sinusoidal current generator, feed-through converter with magnetizing and measuring coils, selective amplifier and amplitude meter, 20 characterized in that, in order to increase the control accuracy, it is equipped with a linear detector with two outputs connected to the measuring winding of the converter 25 unipolar signals, an inverter whose input is connected to one of the outputs of the linear detector, and an iTopoM sum, whose inputs are connected respectively to the second output of the linear detector and the output of the inverter and the output is connected to a selective amplifier. by dividing the even harmonic, the signal taken from the transducer measuring coil is detected, the negative or positive half-wave is inverted and summed with the positive or negative half-wave. 2. The method according to p. 3c Device for non-destructive testing by the method of higher harmonics, containing series-connected adjustable sinusoidal current generator, feed-through converter with magnetizing and measuring coils, selective amplifier and amplitude measuring instrument, characterized in that, in order to increase the control accuracy, it is supplied with a linear detector with two outputs connected to the measuring winding of the converter unipolar signals, an inverter, the input of which is connected to one of the outputs of the linear detector, and a sum- iTopoM, whose inputs are connected respectively to the second output of the linear detector and the output of the inverter, and the output is connected to a selective amplifier.