RU99102691A - DEVICE FOR TECHNICAL CONTROL USING VOLTAGE CURRENTS - Google Patents

DEVICE FOR TECHNICAL CONTROL USING VOLTAGE CURRENTS

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Publication number
RU99102691A
RU99102691A RU99102691/28A RU99102691A RU99102691A RU 99102691 A RU99102691 A RU 99102691A RU 99102691/28 A RU99102691/28 A RU 99102691/28A RU 99102691 A RU99102691 A RU 99102691A RU 99102691 A RU99102691 A RU 99102691A
Authority
RU
Russia
Prior art keywords
emitter
coils
coil
emitters
eddy current
Prior art date
Application number
RU99102691/28A
Other languages
Russian (ru)
Other versions
RU2183008C2 (en
Inventor
Андел Петрус Виллем Ван
Мартен Лоренз
Рикки Эдуардо Рикардо Мейер
Марк Теодор Лойер
Original Assignee
Шелл Интернэшнл Рисерч Маатсхаппий Б.В.
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Application filed by Шелл Интернэшнл Рисерч Маатсхаппий Б.В. filed Critical Шелл Интернэшнл Рисерч Маатсхаппий Б.В.
Publication of RU99102691A publication Critical patent/RU99102691A/en
Application granted granted Critical
Publication of RU2183008C2 publication Critical patent/RU2183008C2/en

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Claims (1)

1. Устройство (9) технического контроля предмета из электропроводного материала (2) с близлежащей поверхностью (17), которое содержит датчик астатических сигналов для формирования в предмете электромагнитного поля, и приемник для измерения отклонений вихревого тока, формируемого астатическим электромагнитным полем, и для выработки сигнала, представляющего затухание вихревого тока, отличающееся тем, что датчик астатических сигналов содержит, по меньшей мере, два поперечно отделенных друг от друга эмиттера (11, 12; 41, 42) для излучения электромагнитного поля, при этом эмиттеры (11, 12; 41, 42) во время обычной эксплуатации запускаются таким образом, что усиливается результирующее электромагнитное поле в центральной области между эмиттерами (11, 12; 41, 42).1. A device (9) for the technical control of an object of electrically conductive material (2) with a nearby surface (17), which contains a sensor of astatic signals for generating an electromagnetic field in the object, and a receiver for measuring the eddy current deviations generated by the astatic electromagnetic field, and for generating a signal representing eddy current attenuation, characterized in that the sensor of astatic signals contains at least two emitter transversely separated from each other (11, 12; 41, 42) for emitting an electron netic fields, wherein the emitters (11, 12; 41, 42) during normal operation are started so that the resulting electromagnetic field is enhanced in the central region between the emitters (11, 12; 41, 42). 2. Устройство по п.1, отличающееся тем, что датчик астатических сигналов содержит, по меньшей мере, одну пару поперечно отделенных друг от друга эмиттеров (11, 12; 41, 42). 2. The device according to claim 1, characterized in that the sensor of astatic signals contains at least one pair of emitters transversely separated from each other (11, 12; 41, 42). 3. Устройство по п.2, отличающееся тем, что каждая пара поперечно отделенных друг от друга эмиттеров (11, 12; 41, 42) содержит первую эмиттерную катушку (11, 41) и вторую эмиттерную катушку (12, 42), расположенные практически параллельно близлежащей поверхности (17) предмета (2). 3. The device according to claim 2, characterized in that each pair of emitter transversely separated from each other (11, 12; 41, 42) contains a first emitter coil (11, 41) and a second emitter coil (12, 42) located practically parallel to the nearby surface (17) of the item (2). 4. Устройство по п.2 или 4, отличающееся тем, что содержит множество пар эмиттерных катушек (50, 52, 54, 56; 60, 62, 64, 66, 68, 70). 4. The device according to claim 2 or 4, characterized in that it contains many pairs of emitter coils (50, 52, 54, 56; 60, 62, 64, 66, 68, 70). 5. Устройство по п.4, отличающееся тем, что центры (59) эмиттерных катушек (60, 62, 64, 66, 68, 70) расположены по дуге полуокружности (71) в плоскости, перпендикулярной близлежащей поверхности (17) предмета (2), и тем, что эмиттерные катушки (60, 62, 64, 66, 68, 70) расположены перпендикулярно этой дуге. 5. The device according to claim 4, characterized in that the centers (59) of the emitter coils (60, 62, 64, 66, 68, 70) are located along an arc of a semicircle (71) in a plane perpendicular to the nearby surface (17) of the object (2 ), and the fact that the emitter coils (60, 62, 64, 66, 68, 70) are perpendicular to this arc. 6. Устройство по п. 5, отличающееся тем, что внутри эмиттерных катушек расположена полукруглая полоса из ферромагнитного материала. 6. The device according to p. 5, characterized in that inside the emitter coils is a semicircular strip of ferromagnetic material. 7. Устройство по п. 1, отличающееся тем, что горизонтально отделенные друг от друга эмиттеры содержат катушку, практически параллельную близлежащей поверхности (17) предмета (2), а полоса из ферромагнитного материала практически перпендикулярна близлежащей поверхности (17) предмета (2). 7. The device according to claim 1, characterized in that the emitters horizontally separated from each other contain a coil practically parallel to the nearby surface (17) of the object (2), and a strip of ferromagnetic material is almost perpendicular to the nearby surface (17) of the object (2). 8. Устройство по п.1, отличающееся тем, что поперечно отделенные друг от друга эмиттеры состоят из эмиттерной катушки, имеющей форму цифры 8, и практически параллельной близлежащей поверхности (17) предмета (2). 8. The device according to claim 1, characterized in that the emitters transversely separated from each other consist of an emitter coil having the shape of the number 8 and almost parallel to the nearby surface (17) of the object (2). 9. Устройство по одному из пп.1 - 8, отличающееся тем, что приемник содержит, по меньшей мере, одну приемную катушку (20, 22; 46), установленную для приема электромагнитного поля, формируемого вихревым током в предмете (2). 9. The device according to one of claims 1 to 8, characterized in that the receiver comprises at least one receiving coil (20, 22; 46) installed to receive the electromagnetic field generated by the eddy current in the object (2). 10. Устройство по п.9, отличающееся тем, что приемник содержит, по меньшей мере, одну пару приемных катушек (20, 22), включающую в себя первую приемную катушку (20) и вторую приемную катушку (22), расположенные по обеим сторонам центральной области (26). 10. The device according to claim 9, characterized in that the receiver comprises at least one pair of receiving coils (20, 22), including a first receiving coil (20) and a second receiving coil (22) located on both sides central area (26). 11. Устройство по п.10, отличающееся тем, что каждая пара приемных катушек (20, 22) выровнена по отношению к соответствующей паре эмиттерных катушек (11, 12)
12. Устройство по п.11, отличающееся тем, что размер приемных катушек (20, 22) меньше размера соответствующих эмиттерных катушек (11, 12), причем продольные оси (23, 24) приемных катушек (20, 22) проходят между продольными осями (13, 25) соответствующих эмиттерных катушек (11, 12).11. The device according to claim 10, characterized in that each pair of receiving coils (20, 22) is aligned with the corresponding pair of emitter coils (11, 12)
12. The device according to claim 11, characterized in that the size of the receiving coils (20, 22) is smaller than the size of the corresponding emitter coils (11, 12), and the longitudinal axes (23, 24) of the receiving coils (20, 22) pass between the longitudinal axes (13, 25) of the corresponding emitter coils (11, 12). 13. Устройство по одному из пп.9 - 12, отличающееся тем, что каждая приемная катушка (20, 22) расположена между эмиттерными катушками (11, 12) и предметом (2). 13. The device according to one of claims 9 to 12, characterized in that each receiving coil (20, 22) is located between the emitter coils (11, 12) and the item (2). 14. Способ измерения толщины предмета из электропроводного материала, содержащий наведение в предмете импульсного вихревого тока, определение затухания вихревого тока и формирование сигнала, представляющего затухание, и определение по сигналу толщины предмета, отличающийся тем, что этап определения по сигналу толщины предмета содержит выбор первого значения и второго, меньшего, значения амплитуды сигнала, измерение длины интервала времени, на котором сигнал затухает с первого значения до второго значения, и определение по длине интервала времени толщины предмета. 14. A method for measuring the thickness of an object from an electrically conductive material, comprising pointing an eddy current into the object, determining the attenuation of the eddy current and generating a signal representing the attenuation, and determining from the signal the thickness of the object, characterized in that the step of determining from the signal the thickness of the object comprises selecting a first value and the second, smaller value of the amplitude of the signal, measuring the length of the time interval in which the signal decays from the first value to the second value, and determining the length of the interval la object thickness time. 15. Способ по п. 14, отличающийся тем, что толщину (Wt) определяют по длине интервала времени (ti) с помощью следующего равенства: Wt = (ti - А)/В, где А и В являются заранее определенными калибровочными постоянными.15. The method according to p. 14, characterized in that the thickness (W t ) is determined by the length of the time interval (t i ) using the following equality: W t = (t i - A) / B, where A and B are predetermined gauge constants.
RU99102691/28A 1996-07-12 1997-07-11 Apparatus for inspection of technical condition of objects with use of eddy current RU2183008C2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP96201978 1996-07-12
EP96201978.2 1996-07-12

Publications (2)

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RU99102691A true RU99102691A (en) 2000-11-27
RU2183008C2 RU2183008C2 (en) 2002-05-27

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US (1) US6291992B1 (en)
EP (1) EP0910784B1 (en)
JP (1) JP4263244B2 (en)
CN (2) CN1155795C (en)
DE (1) DE69712759T2 (en)
ES (1) ES2177994T3 (en)
NO (1) NO331373B1 (en)
RU (1) RU2183008C2 (en)
WO (1) WO1998002714A1 (en)

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