SU853518A1

SU853518A1 - Through eddy-current device

Info

Publication number: SU853518A1
Application number: SU792843494A
Authority: SU
Inventors: Валерий Федорович Булгаков; Владимир Константинович Жуков
Priority date: 1979-11-29
Filing date: 1979-11-29
Publication date: 1981-08-07

Description

1one

Изобретение относитс к вихретоковой дефектоскопии металлов и может быть использовано дл обнаружени локальных дефектов в прокате.The invention relates to eddy current flaw detection of metals and can be used to detect local defects in rolled products.

Известно проходное вихретоковое устройство, содержащее два преобразовател и св занный с ними индикатор сигналов l J.A eddy-current pass-through device is known, containing two transducers and a signal indicator l J associated with them

ч)днако это устройство не обеспечивает достаточной точности контрол из-за вли ни нестабильности зазора между преобразовател ми и контролируемым объектом.h) However, this device does not provide sufficient control accuracy due to the influence of the instability of the gap between the transducers and the object being monitored.

Наиболее близким к изобретению техническим решением вл етс проходное вихретоковое устройство, содержащее два дифференциальных вихретоковых преобразовател и св занный с ними индикатор разности сигналов . 2.The closest technical solution to the invention is an eddy-current pass-through device containing two differential eddy-current converters and a signal difference indicator associated with them. 2

Однако точность контрол этим устройством недостаточна из-за отсутстви средств дл компенсацииHowever, the accuracy of control by this device is insufficient due to the lack of funds to compensate

нестабильности зазора между преобразовател ми и контролируекым объектом .the instability of the gap between the transducers and the controlled object.

Цель изобретени - повьопение точности контрол .The purpose of the invention is to improve the accuracy of control.

Это достигаетс тем, что устройство снабжено дифференцирующими чейками , включенными между преобразова ел ми и индикатором разности сигналов, возбуждающие обмотки преобразователей объединены в одну обмотку , измерительные обмотки расположены симметрично по обе стороны от оси этой обмотки на разных рассто ни х от нее, а посто нные времени дифференцирующих чеек обратно пропорциональны указанным рассто ни м.This is achieved by the fact that the device is equipped with differentiating cells connected between the transducers and the signal difference indicator, the exciting windings of the transducers are combined into one winding, the measuring windings are located symmetrically on both sides of the axis of this winding at different distances from it, and the constant the time of the differentiating cells is inversely proportional to the specified distance m.

На фиг.1 представлена блок-схема проходного вихретокового устройства; на фиг.2 - эскиз вихретоковых преобразователей; разрез.Figure 1 presents the block diagram of the flow eddy-current device; figure 2 - sketch of eddy current transducers; incision.

Claims

The device contains two differential eddy current transducers 1 and 2, the exciting winding 3 of which is connected to the signal generator 4, and the measuring windings 5-8 are connected to the differentiating cells 9 and 10, which are connected to the indicator 11 of the signal difference. The measuring windings 5-8 are located symmetrically with respect to the axis of the exciting winding 3 at different distances from it, and the time constants of the cells 9 and 10 are inversely proportional to these distances. The device operates as follows. The controlled object 12 is placed into the cavity of the transducers, when the latter are displaced in the excited 3 windings in the 3 states on the windings 5-6 and 7-8, if there is a defect in the object 12, signals appear that are differentiated by the cells 9 and 10. Gender: indicator 11 then goes. At the aforementioned constant times of these cells, the radial displacements or distortions of the transducers relative to the object being monitored are less affected by the signal: from defects, which improves the accuracy of the control 84 stroystvom. An inventive eddy current device comprising two differential eddy current transducers and a signal difference indicator associated therewith, characterized in that, in order to improve the control accuracy, it is equipped with differentiating cells connected between the converters and the signal difference indicator, the exciter windings of the converters are combined in one winding, the measuring windings are located symmetrically on either side of the axis of this winding at different distances from it, and the constant windings ifferentsiruyuischh cells obatno proportional to said rasstoni m. Sources of information taken into account during the examination 1. USSR author's certificate No. 580494, 13 01 N 27/86, 1974.

2. USSR author's certificate No. 596874, G01 N 27/86, 1975 (prototype).