SU842557A1

SU842557A1 - Magnetic flaw detector

Info

Publication number: SU842557A1
Application number: SU792737922A
Authority: SU
Inventors: Александр Николаевич Бодров; Владимир Яковлевич Козлов; Александр Федорович Ерашов
Original assignee: Научно-Производственное Объедине-Ние По Технологии Машиностроения
Priority date: 1979-03-20
Filing date: 1979-03-20
Publication date: 1981-06-30

Description

Изобретение относится к неразрушающему контролю ферромагнитных изделий магнитопорошковым методом и может быть использовано для обнаружения , нарушений сплошности при контроле ме- ⁵таллических изделий и их сварных соединений.The invention relates to non-destructive testing of ferromagnetic articles magnetic particle method and can be used to detect discontinuities in the control Me- ^5-metallic articles and their welded connections.

Известен магнитный дефектоскоп, содержащий силовой трансформатор, уп- ⁰равняемый симметричный вентиль <симистор), включенный последовательно с первичной обмоткой силового выходного трансформатора, два силовых вентиля, соединенных по схеме удвое- 15 ния выпрямленного напряжения с нулевым выходом вторичной обмотки силового -трансформатора, блок фазоимпульсного управления, с выхода которого поступают запускающие импульсы на уп- 20 равняемый вентиль, связанный с блоком коммутации и управления дефектоскопом, aerate дополнительный трансформатор для питания блока фазоимпульсного управления. Переменное, выпрям-25 ленное или импульсное напряжение вторичной обмотки силового трансформатора подводится к'разделенным силовым клеммам, к которым подключаются намагничивающие устройства U]* *Known magnetic flaw detector comprising a power transformer, yn equals ⁰ symmetric valve <triac) connected in series with the primary winding of the power output transformer, two power valve connected in doubling circuit 15 Nia rectified voltage output with zero -transformatora secondary winding of the power unit phase-pulse control, from the output of which triggering pulses are supplied to an equalized valve connected to the switching and control unit of the flaw detector, aerate additional transformer p for positionally power control unit. Alternating, rectified-25 or impulse voltage of the secondary winding of the power transformer is supplied to the 'separated power terminals to which the magnetizing devices are connected U] * *

Однако известное устройство имеет низкую надежность.However, the known device has low reliability.

Наиболее близким к предлагаемому магнитный дефектоскоп содержит силовой трансформатор, включенный последовательно с его вторичной обмоткой силовой вентиль, блок коммутации, соединенный с ним последовательно блок фазоимпульсногд управления с источником питания и два соединенных встречно-параллельно управляемых силовых вентиля., связанных с блоком коммутации и одной из обмоток силового трансформатора. Выводы переменного и выпрямленного напряжения вторичной обмотки силового трансформатора подведены к отдельным парам силовых клемм дефектоскопа для подсоединения 'намагничивающих устройств (2].Closest to the proposed magnetic flaw detector contains a power transformer connected in series with its secondary winding to a power valve, a switching unit, a phase-pulse control unit connected to it in series with a power source, and two inter-parallel-controlled power valves connected to the switching unit and one of power transformer windings. The terminals of the alternating and rectified voltage of the secondary winding of the power transformer are connected to separate pairs of power terminals of the flaw detector for connecting 'magnetizing devices (2).

Недостатком известного дефектоскопа является низкая надежность, так как повреждение вентилей или цепи управления может привести к выходу из строя трансформатора. Наличие нескольких пар силовых клемм для снятия различных видов токой намагничивания .(переменного, выпрямленного, двухили однополупериодного) и двух источников питания усложняют конструкцию дефектоскопа и технологию проведения контроля, ограничивает его функцио-: нальные возможности.A disadvantage of the known flaw detector is low reliability, since damage to the valves or the control circuit can lead to failure of the transformer. The presence of several pairs of power terminals for removing various types of current magnetization (alternating, rectified, two-wave or half-wave) and two power supplies complicate the design of the flaw detector and the technology for monitoring, and limits its functional capabilities.

Цель изобретения - повышение надежности и расширение функциональных возможностей дефектоскопа.The purpose of the invention is to increase reliability and expand the functionality of the flaw detector.

Указанная цель достигается тем, что силовой вентиль выполнен управляв- ^эмым и соединен катодом с одним из концов вторичной обмотки силового трансформатора, анодом через управляемые вентили - с вторым ее концом, а уп- . равняющими электродами все вентили связаны с блоком коммутации.This object is achieved in that the power valve is formed by direct upravlyav- ^e and the cathode is connected to one end of the power transformer secondary winding, the anode through controlled valves - with its second end, and yn. By equalizing electrodes, all valves are connected to the switching unit.

Источник питания фазоимпульсного блока выполнен в виде дополнительной обмотки силового трансформатора.The power source of the phase-pulse block is made in the form of an additional winding of the power transformer.

Иа чертеже приведена функциональ- 15 ная схема магнитного дефектоскопа.The drawing shows a functional diagram of a magnetic flaw detector.

Дефектоскоп содержит силовой понижающий трансформатор 1, первичная обмотка 2 которого подключена к сети переменного то^а через автомат 3 за- 20 щиты от перегрузок, а вторичная обмотка состоит из двух последовательно включенных маловитковых обмоток 4 . и 5, общая точка которых соединена с силовой клеммой 6, а выводы через регулятор 7 тока, состоящий из управляемых вентилей (тиристоров) 8,9 и 10, . соединены с силовой клеммой 11. Дефектоскоп содержит также блок 12 коммутации, связанный выходом с управляющими электродами^управляемых вентилей 8,9 и 10; а входом - с выходом блока 13 фазоимпульсного управления, питание на который поступает с дополнительной обмотки 14 силового трансформатора 1. К силовым клеммам 6 и 11, расположенным на передней панели дефектоскопа, подключаются электроконтакты 15 (или силовой кабель) соответственно для циркулярного или продольного намагничивания изделия 16,The flaw detector contains a power step-down transformer 1, the primary winding 2 of which is connected to an alternating current network, and through the automatic machine 3, 20 are protected against overloads, and the secondary winding consists of two low-turn windings 4 connected in series. and 5, the common point of which is connected to the power terminal 6, and the terminals through the current regulator 7, consisting of controlled valves (thyristors) 8.9 and 10,. connected to the power terminal 11. The flaw detector also includes a switching unit 12, connected by an output to the control electrodes ^ of the controlled valves 8,9 and 10; and the input - with the output of the phase-pulse control unit 13, the power of which is supplied from the additional winding 14 of the power transformer 1. To the power terminals 6 and 11 located on the front panel of the flaw detector, the electrical contacts 15 (or power cable) are connected respectively for circular or longitudinal magnetization of the product 16,

Дефектоскоп работает следующим образом.Flaw detector works as follows.

При включении автомата,3 напряжение сети поступает на первичную обмотку 2 трансформатора 1. С обмотки 14 этого же трансформатора напряжение поступает на вход блока 13 фазоимпульсного управления, состоящего из фазовращателя, формирователя управляющих импульсов и импульсного трансформатора (не показаны).When the machine is turned on, 3 the mains voltage is supplied to the primary winding 2 of the transformer 1. From the winding 14 of the same transformer, the voltage is supplied to the input of the phase-pulse control unit 13, consisting of a phase shifter, a control pulse shaper, and a pulse transformer (not shown).

Напряжение,преобразованное в импульс малой длительности и сдвинутое по фазе фазовращателем блока 13 относительно напряжения питающей сети, поступает через блок 12 коммутаций на управляющие электроды вентилей 8 9 и 10. Блок 12 коммутации содержит исполнительное реле (не показано) для включения и выключения отпирающих импульсов, управляющих вентилями 8,9 и 10, и переключатель рода тока (не показан). К; выходным клеммам 6 и 11 подключаются электроконтакты 15 для циркулярного намагничи вания участка изделия 16 (или силовой кабель для продольного намагничивания). Вид намагничивающего тока зависит от конкретных задач контроля, размеров! и материала изделия 16 и устанавливается переключателем блока 12 коммутации. Установка величины намагничивающего тока осуществляется с помощью блока 13 фазоимпульсного управления. При изменении по фазе угла отпирания запускающих импульсов относительно напряжения на аноде соответствующего вентиля изменяется время его работы и, соответственно, величина намагничивающего тока. Намагниченный участок изделия покрывается индикаторной средой, и по распределению магнитных частиц порошка судят о наличии дефектов на поверхности изделий.The voltage converted into a short pulse and phase shifted by the phase shifter of block 13 relative to the supply voltage is supplied through the switching unit 12 to the control electrodes of the valves 8 9 and 10. The switching unit 12 contains an actuating relay (not shown) for turning on and off the unlocking pulses, control valves 8.9 and 10, and a current type switch (not shown). TO; the output terminals 6 and 11 are connected electrical contacts 15 for circular magnetization of the product area 16 (or a power cable for longitudinal magnetization). The type of magnetizing current depends on the specific control tasks, sizes! and product material 16 and is set by the switch of the switching unit 12. The magnitude of the magnetizing current is set using the block 13 of the phase-pulse control. When the phase of the unlocking pulses of the triggering pulses changes with respect to the voltage at the anode of the corresponding valve, its operating time and, accordingly, the magnetizing current change. The magnetized area of the product is covered with an indicator medium, and the presence of defects on the surface of the products is judged by the distribution of magnetic particles of the powder.

Дефектоскоп позволяет при наличии только двух силовых клемм б и 11 осуществить переключение с помощью блока 12 коммутации рода тока при контроле в режиме приложенного поля цли остаточной намагниченности, что расширяет его функциональные возможности . Так, при работе вентилей 8 и 9 на выходных клеммах би 11 будет переменное напряжение, необходимое как для намагничивания, так и для размагничивания изделий при магнитопорошковом методе контроля. При работе вентилей 9 и 10 на выходных клеммах 6 и 11 будет выпрямленное двухполупериодное напряжение, а при работе только одного из трех вентилей, 1например 8,- выпрямленное однополупериодное, причем включение управляющего вентиля 9 (или 10) обеспечивает на выходе другую полярность выпрямленного тока. Одновременно при таком включении вентилей повышается надеж-. ность дефектоскопа, так как выход из строя цепей управления или управляемых вентилей приводит лишь к изменению рода намагничивающего тока на выходных клеммах дефектоскопа.The flaw detector allows, if there are only two power terminals b and 11, to switch using the current type switching unit 12 when monitoring in the applied field mode, the residual magnetization, which expands its functionality. So, when the valves 8 and 9 are operating, the bi 11 output terminals will have an alternating voltage, which is necessary both for magnetization and demagnetization of products using the magnetic particle inspection method. When the valves 9 and 10 are operating, the output terminals 6 and 11 will have a rectified half-wave voltage, and when only one of the three valves, 1 for example 8, will operate a rectified half-wave voltage, and the inclusion of the control valve 9 (or 10) provides a different polarity of the rectified current at the output. At the same time, with this inclusion of valves increases reliability. flaw detector, since failure of control circuits or controlled valves only leads to a change in the type of magnetizing current at the output terminals of the flaw detector.

Claims

The invention relates to the non-destructive control of ferromagnetic products by the magnetic particle method and can be used to detect alloys in the control of metal products and their welded joints. A magnetic flaw detector is known, containing a power transformer, a symmetric gate (with a mystor), connected in series with the primary winding of a power output transformer, two power valves connected according to a double rectified voltage circuit with a zero output of a power winding of a power transformer, and a phase pulse unit control, from the output of which the triggering pulses are fed to the controlled valve connected to the switchgear switching and control unit, and a large-scale transformer for power supply of the phase-impulse control unit. The alternating, rectified, or pulsed voltage of the etiric winding of a power transformer a is divided into {power terminals, to which magnetizers t are connected. However, the known device has low reliability. Closest to the proposed magnetic flaw detector, there is a power transformer, a power valve connected in series with its secondary winding, a switching unit, a phase-impulse control unit connected in series with a power source, and two connected anti-parallel controlled power valves connected to the unit switching and one of the windings of the power transformer. The outputs of the alternating and rectified voltage of the secondary winding of the power transformer are connected to the individual pairs of power terminals of the flaw detector for connecting magnetizing devices t2. A disadvantage of the known flaw detector is low reliability, since damage to the valves or control circuit may lead to the failure of the transformer. The presence of several pairs of power terminals for the removal of various types of magnetizing tokens. (Variable, rectified, two or one time) and two power sources complicate the design of the instrument and the control technology, limiting its functionality. The purpose of the invention is to increase the reliability and expand the functional capabilities of the flaw detector. . This goal is achieved by the fact that the power valve is controlled and connected by a cathode to one of the secondary windings of the power transformer, the anode through controlled valves to its second end, and all the valves are connected to the switching unit by control electrodes. The power supply of the phase-pulse unit is made in the form of an additional winding of the power transformer. The drawing shows the functional diagram of a magnetic flaw detector. The flaw detector contains a power pinch transformer 1, the primary winding 2 of which is connected to the AC network through an automatic machine 3 overload protection, and the secondary winding consists of two series-connected low-turn windings and 5, the common point of which is connected to the power terminal b, and the outputs through the regulator 7, consisting of controlled valves (thyristors) 3.9 and 10, connected to the power terminal 11. The flaw detector also contains a switching unit 12 connected to the control electrodes of controlled valves 8.9 and 10 a ; entrance - with the output of the phase-impulse control unit 13, which is supplied with power from the additional winding 14 of the power transformer 1. The power contacts 15 (or the power cable) are respectively connected to the power terminals 6 and 11 located on the front panel of the instrument that are used for circular or longitudinal magnetization of the product 16 The flaw detector works as follows. When the automat is turned on, the 3 mains voltage goes to the primary winding 2 of the transformer 1. From the winding 14 of the same transformer, the voltage goes to the input of the phase-impulse control unit 13 consisting of a phase shifter, a control pulse shaper and a pulse transformer (not shown), A transformer converted into a pulse of short duration and phase shifted by the phase shifter of unit 13 with respect to the supply voltage enters through the switching unit 12 to the control elements 1 (three valves 9 and 10). an actuating relay (not shown) for switching on and off unlocking pulses g controlled by valves 8.9 and 10, and a switch of the current type (not shown), K; electrical contacts 15 are connected to the terminals B and 11 for circularly magnetizing the area of the product 16 (.or power cable for longitudinal magnetization). The type of magnetizing current depends on the specific control tasks, sizes and material of the product 16 and is set by the switch of the switching unit 12. The magnitude of the magnetizing current is set using the unit 13 of the phase-impulse control. When the angle of unlocking of the start-up of the pulses changes with respect to the voltage at the anode of the corresponding valve, its operation time and, accordingly, the magnitude of the magnetized current, changes. The magnetized area of the product is covered with indicator medium, and the presence of defects on the surface of the products is judged by the distribution of the magnetic particles of the powder. The flaw detector allows, when there are only two power terminals 6 and 11, to switch using the switching unit 12 of the type of current during control in the applied field 1 or residual magnetization, which expands its functionality. Thus, when the valves 8 and 9 are operated, at the output terminals 6 and 11 there will be an alternating voltage necessary both for magnetization and for demagnetization of products with the magnetic-powder control method. When valves 9 and 10 are working, at the output terminals 6 and 11 there will be a rectified full-wave voltage, and when only one of the three valves is working, Jnapripe 8, will be rectified half-wave, and turning on control valve 9 (or 10) will provide another output polarity of rectified current. At the same time, with such switching of the valves, the reliability increases. flaw detector, since the failure of control circuits or controlled gates leads only to a change in the type of magnetizing current at the output terminals of the flaw detector. Claim 1. Magnetic flaw detector containing a power transformer connected in series with its secondary winding, a power valve, a switching unit connected in series with it a phase-impulse control unit with a power source and two connected No. 1e anti-parallel-controlled power valves connected Connected with the switching unit and one of the windings of the power transformer, characterized in that, in order to increase the reliability and enhance the functionality of the flaw detector, the power. connected by a cathode to one of the secondary power circuits

the transformer, the anode through controlled valves to its second end, and the control electrodes, all the valves are connected to the wiring of the commutation,

2. The flaw detector according to l, 1, about t l and that the power source of the phase-impulse unit is made as an additional winding of the power transformer.

Sources of information taken into account in the examination

1. Control of stss parts using mobile magnetic flaw detector VD-50P. Toolkit . Chisinau, Timpul, 1978, p.6.

2. Development and production of a prototype of a mobile magnetic flaw detector. Report A-120, TsNIITMASH, 1973, p. 21-24 (prototype ;.

/ sg