US3855530A - Magnetic metal defect-detecting apparatus - Google Patents

Magnetic metal defect-detecting apparatus Download PDF

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Publication number
US3855530A
US3855530A US00397655A US39765573A US3855530A US 3855530 A US3855530 A US 3855530A US 00397655 A US00397655 A US 00397655A US 39765573 A US39765573 A US 39765573A US 3855530 A US3855530 A US 3855530A
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magnetic
single phase
alternating current
phase alternating
coil
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US00397655A
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English (en)
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T Fuji
Y Otsuka
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JFE Engineering Corp
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Nippon Kokan Ltd
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
    • G01N27/82—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws
    • G01N27/83—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws by investigating stray magnetic fields
    • G01N27/84—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws by investigating stray magnetic fields by applying magnetic powder or magnetic ink

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  • a magnetic metal defect-detecting apparatus comprising a cross-shaped magnetic core assembly prepared from two pairs ofmagnetic polemembers providing Sept. 19, 1972 Japan;.'....' 47-93845 2 v two pans of magnetlc poles mtersectmg each other at a 1 right angles and'each fitted with a caster at the end; a (gl.
  • This invention relates to a magnetic metal defectdetecting apparatus designed alternately to apply each of two magnetic fluxes to a magnetizable test material I in perpendicularly intersecting directions;
  • a known process of magnetically detecting any defeet in magnetizable metal material being tested consists in spreading powders of magnetizable metal material over the surface of said test material before it is magnetized by a magnetic field generator. If, in this case, the magnetized test material is free from any defect, then magnetized metal powders will be uniformly distributed in the direction in which a magnetic flux is applied. If, however, the test material has a defect, then a leakage magnetic flux willbe released to the outside from the surface of that part of the test material which ble of effecting a relatively easy defect detecting operation in two mutually perpendicular directions by a single step with little fatigue to an operator.
  • a magnetic metal defect-detecting apparatus comprising a cross-shaped magnetic core assembly including two pairs'of magnetic pole members providing two pairs of magnetic poles intersecting each other; a
  • I first and a second coil wound about the two pairs of magnetic pole members and a power supply device including a source of single phase alternating current; and at least a pair of rectifiers coupled to the power supply device-forsupplying the first coil with single I phase alternating current of positive half wave and the through that part of the test material which'is defined between the two opposite poles of the electromagnet.
  • the magnetic flux is directed along a line connecting the magnetic poles.
  • the test material contains an elongate defect extending perpendicular to the axis of the magnetic flux, then a leakage magnetic flux resulting from the defect will have a sufficiently high density to cause a-large amount of magnetizable metal powders spread on the test material to be absorbed to the surface of that part of the test material which contains the defect. In the above-mentioned case, therefore, a defect can be detected very sensitively. Where, however, an elongate defect extends along the axis of the magnetic flux, then a leakage magnetic flux delivered from the defective portion of the test material will have such a lowdensity as to attain the absorption of only a small amount of magnetizable metal powders,
  • a magnetic metal defect-detecting apparatus wherein the end of each magnetic pole member of the cross-shaped magnetic core assembly is fitted with a caster so as to facilitate the handling of said detecting apparatus which is of relatively great weight.
  • FIG. 1 is an oblique view of the magnetic metal defect-detecting apparatus of this invention
  • FIG. 2 is a circuit diagram of the detecting apparatus of FIG. 1;
  • FIG. 3 presents the manner in which the magnetic detection of a metal defect is effected by spreading magnetizable metal powders over the surface of a piece of metalmaterial being tested;
  • FIG. 4 is a side view of a modification of the magnetic meta] defect-detecting apparatus of the invention
  • FIG. 5 is a circuit diagram of a power supply device modified from FIG. 2
  • FIG. 6 is a-circuit diagram of a metal defect-detecting apparatus according'to another embodiment of the invention.
  • the bridging sides 4 of themagnetic pole members 24 and 28 facing each other across the joint of the core sections 8 and 10 are respectively wound with an exactly half portion of a first exciting coil 34.
  • the exciting coils 34' and 36 are each connected at one end to two cores of a 4-core power supply cable 40 through the respective contacts of a 2- and 60. Therefore, powders of magnetizable metal material are similarly attracted by said leakage magnetic flux denoting a vector sum, thereby carrying out the detection of a defect. Accordingly, itis possible to detect contact push-button switch 38 mounted on the handle l2, and at the other end to the remaining two cores of said cable 40.
  • This 4-core cable 40 is connected to a power supply device 42 shown in FIG. 2.
  • the power supply device 42 consists of a source 44 of single phase alternating current and four diodes 46, 48, 50 and52.
  • One end of said single phase A.C. source 44 is connected to one, end of the coil 34 as one contact 54 of the 2-contact switch 38.
  • the other end of said power source 44 is connected to the other end of the coil 34 through the cathode and anode of the diode 52.
  • Said one end of the power source 44 is also connected to one end of the coil 36 through the cathode and anode of the diode 48.
  • Said other end of the power source 44 is also connected to the other end of the coil 36 through the anode and cathode of the diode 50 and the other contact 56 of the 2-contact switch 38.
  • the push-button 38 is depressed bygripping the handle 12, 1 current of positive half wave is supplied from the single phase A.C. source 44to one exciting coil 34. through the diodes 46 and 52, then the magnetic pole members 24 and 28 indicate, for example, the N andS poles respectively.
  • a magnetic flux 58 passes through the steel plate 22 in the direction of solid line arrows shown in FIG. 1, namely, from the magnetic pole member 24 (N pole) to the magnetic pole member '28 (S pole).
  • a leakage magnetic flux representing a vector sum .of the magnetic fluxes 58 and 60 takes place with respect to a defect obliquely intersecting either of said fluxes 58 through the anode and cathode of the diode 46 as well any defect occurring in that part of the steel plate 22 in which there is placed the cross-shaped magnetic core assembly 2 of this invention.
  • the magnetic core assembly 2 whose two groups of magnetic pole members 24-26 and 28-30 are fitted with casters 32 can be freely rotated over the surface of the steel plate 22 when the handle 12 of said assembly 2 is gripped by an operators hand, thereby causing either of the magnetic fluxes 58 and 60 perpendicularly to intersect any defect contained in the steel plate 22. Therefore, only one rotation of the cross-shaped magnetic core assembly 2 on the surface of the steel plate 22 is sufficient to detect its defects extending in all directions at once with a highest possible sensitivity.
  • the two core sections 8 and 10 were fixed at the joint by the bolt 18 and nut 20.
  • said core sections 8 and 10 may be made rotatable ina vertical direction about the bolt 18. This arrangement can cause the casters fitted to the ends of the magnetic pole members 24-26 and 28-30 always to contact the surface of the steel plate 22 even when said surface is slightly uneven, thereby enablinga uniform strength of magnetizationto be always applied to the this invention can be applied in detecting any defect contained in the angular welded section of two pieces of the steel plate 22 or the angular bent section of a single piece thereof.
  • FIG. 4 illustrates said application, the
  • a magnetizable test material is supposed to be two steel plates 22a and 22b welded together on the edge at right angles.
  • the mag-' netic pole members 24 and 26 constituting one section of the cross-shaped magnetic core assembly 2 are cut obliquely at the end so as to contact the inner surfaces of the steel plates 22a and 22b welded together at right angles.
  • the magnetic pole members 28 and 30 are likewise obliquely cut at the end.
  • the cross-shaped magnetic core assembly, 2 thus constructed can easily detect a defect present in the angular section of a test metal material.
  • the foregoing embodiment relates to the case where there was used a cross-shaped magnetic core assembly 2 constructed by joining two core sections, each of which was fonned of a plurality of laminated steel plates. Obviously, it is possible to use a cross-shaped magnetic core assembly 2 formed into an integral body.
  • the power supply device 42 of FIG. 2 consisted of four diodes 46, 48, 50 and 52. However, it is possible to connect, as shown in FIG. 5, one end of the power source 1 44 to one end of the coils36 and 38 respectively through two diodes 46 and 48 of the indicated polarity and connect the other ends of the coils 36 and 38 jointly to the other end of the power source 44. Still, this invention can be operated with'the same effect. This arrangement only requires two diodes as compared with the circuit of FIG. 2, attaining simple construction andlow cost.
  • FIG. 6 shows the arrangement of another embodi- 'ment' of this invention which enables two magnetic fluxes to be applied in directions intersecting each other exactly at right angles even when a steel plate 'being tested hasa property of retaining a relatively large amount of residual magnetism.
  • one end of the single phase A.C. source 44 is con nected to one end of the coil 36 and also to the cathode of a diode 70.
  • the other end of said A.C. source 44 is connected to one end of the coil 34 and also to the cathode of a diode 72.
  • the anodes of the diodes 70 and 72 are jointly connected to one end'of a variable resistor 74, the other end of which is connected to the junction of the coils 34 and 36.
  • a main current runs through the coil 36, variable resistor 74 and diode 72 in the. order mentioned and at this time a side current also passes from the coil 36 to the coil 34.
  • a main current is conducted through'the coil 34, variable resistor 74 and diode 70 and simultaneously a side current is introduced from the coil 34 to the coil 36.
  • the coil 36 is supplied with a main current'and the coil 34 is supplied with a side current which travels in an opposite direc tion to that in which a main current flows through said coil 34 in the case of negative half wave current.
  • a residual magnetism resulting from a magnetic flux created by a main current passing through the coil 34 in the case of negative half wave current is offset by a magnetic flux caused by a side current con- 6 negative half wave current.
  • proper adjustment of the capacity of the variable resistor 74 enables a side current to have a sufficient magnitude to eliminate any amount of residual magnetism.
  • a magnetic metal defect-detecting apparatus comprising:
  • a cross-shaped magnetic core assembly including two pairs of magnetic pole members providing two pairs of magnetic poles intersecting each other;
  • a power supply device including a source of single phase alternating current
  • a detecting apparatus comprising: a detecting apparatus according to claim 1 wherein the cross-shaped magnetic core assembly'comprises two pairs of magnetic pole members, each of which is fitted with a caster at the end thereof. j
  • the cross-shaped magnetic core assembly comprises a first laminated core section bent substantially at right angles; a second laminated core'section bent substantially at right angles and so positioned relative to the first laminated core section as to cause the outside of the bent portion to abut against that of the bent portion of the first laminated core section; a joining means for assembling the mutually abutting bent portions of the first and second laminated core sections into a cross-shaped magnetic core; and a handle attached to the magnetic core by the joining means.
  • a detecting apparatus wherein the respective ends of the two pairs of magnetic pole members are located so as to substantially ducted through the coil 34 in the case of positive half wave current. Similarly, a residual magnetism originating with a magnetic flux provided by a main current introduced through the coil 36 in the case of positive half wave is extinguished by a magnetic flux-created by a side current flowing through the coil 36 in the case of contact the surface of a test piece of metal material.
  • a detecting apparatus according to claim 1 wherein the respective ends of the two pairs of mag netic pole members are located so as to contact the inner surfaces of two test pieces of metal material joined on the edge'at right angles.
  • a detecting apparatus according to claim 1 wherein the first and second coils are connected together at one end, and including: v
  • first rectifier and second rectifier having cathodes which are connected to respective corresponding terminals of said single phase alternating current source and anodes which are connected together;
  • variable resistor which is connected between the junction of the anodes of the first and second recti 'fiers and the junction of the connected together ends of the first and second coils;

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
US00397655A 1972-09-19 1973-09-17 Magnetic metal defect-detecting apparatus Expired - Lifetime US3855530A (en)

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JP47093845A JPS4952688A (enrdf_load_stackoverflow) 1972-09-19 1972-09-19

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JP (1) JPS4952688A (enrdf_load_stackoverflow)
DE (1) DE2346999A1 (enrdf_load_stackoverflow)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4379261A (en) * 1980-09-10 1983-04-05 Lakin Kenneth M Rotating magnetic field device for detecting cracks in metal
EP0090190A1 (de) * 1982-03-22 1983-10-05 Mecapec S.A. Verfahren und Einrichtung zur magnetischen Materialfehlerdetektion
WO1993023751A1 (de) * 1992-05-08 1993-11-25 Tiede Gmbh + Co Rissprüfanlagen Vorrichtung zur magnetischen rissprüfung von ferromagnetischen werkstücken
GB2328509A (en) * 1997-08-20 1999-02-24 Jonathan Roger Max Johnson Magnetic particle inspection apparatus
US6316845B1 (en) 1999-11-05 2001-11-13 Parker Research Corporation Battery powered AC electromagnetic yoke for magnetic particle inspection
US6400146B1 (en) 2000-09-12 2002-06-04 Her Majesty The Queen In Right Of Canada As Represented By The Ministry Of Natural Resources Sensor head for ACFM based crack detection
DE102008016255A1 (de) * 2008-03-29 2009-10-01 Illinois Tool Works Inc., Glenview Vorrichtung zur zerstörungsfreien Prüfung ferromagnetischer Werkstücke
WO2010045765A1 (zh) * 2008-10-24 2010-04-29 捷特（北京）探伤设备有限公司 伸缩式交叉磁轭荧光磁粉探伤机
CN101435797B (zh) * 2008-10-24 2011-04-13 捷特（北京）探伤设备有限公司 伸缩式交叉磁轭荧光磁粉探伤机
CN102087245A (zh) * 2010-12-04 2011-06-08 南昌航空大学 基于非晶合金的电磁检测传感器
WO2012158294A1 (en) * 2011-05-17 2012-11-22 Siemens Energy, Inc. Multi directional electromagnetic yoke for inspection of bores
CN103954684A (zh) * 2014-04-23 2014-07-30 厦门大学 一种利用漏磁变化率进行无损检测的方法
US20150228392A1 (en) * 2014-02-13 2015-08-13 Siemens Energy, Inc. Multidirectional magnetic particle inspection system
CN109975388A (zh) * 2017-12-27 2019-07-05 核动力运行研究所 一种基于核电站薄板平面t型焊缝的电磁检测探头
WO2020047849A1 (zh) * 2018-09-07 2020-03-12 中国电建集团山东电力建设第一工程有限公司 一种t型焊接接头检测用交叉电磁轭
CN114034415A (zh) * 2021-10-26 2022-02-11 成都飞机工业（集团）有限责任公司 一种应力检测方法

Families Citing this family (8)

* Cited by examiner, † Cited by third party
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JPS526679U (enrdf_load_stackoverflow) * 1975-07-01 1977-01-18
JPS62124557U (enrdf_load_stackoverflow) * 1986-01-30 1987-08-07
GB2193810A (en) * 1986-08-12 1988-02-17 Inst Prikladnoi Fiziki Akademi Apparatus for measuring mechanical characteristics of steels
DE3709143A1 (de) * 1987-03-20 1988-09-29 Nukem Gmbh Verfahren und vorrichtung zur zerstoerungsfreien pruefung ferromagnetischer koerper mittels magnetisierung
DE10241029B4 (de) * 2002-09-05 2005-08-25 Hirsch, Peter, Dr.-Ing. Prüfvorrichtung
DE102004054127B4 (de) * 2004-11-08 2008-01-03 HPT Hirsch Prüftechnik GmbH Materialprüfungsvorrichtung
DE102014218255A1 (de) 2014-09-11 2016-03-17 HPT Hirsch Prüftechnik GmbH Über die magnetische Behandlung von Werkstücken mittels Vierpoltechnik
JP6529896B2 (ja) * 2015-11-19 2019-06-12 株式会社コベルコ科研 被検査物の地際部分の減肉状態を検知するための渦流探傷プローブ及び渦流探傷プローブを用いた減肉検知方法

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US1893074A (en) * 1929-06-18 1933-01-03 Sperry Prod Inc Flaw detector
DE847661C (de) * 1943-11-14 1952-08-25 Ernst Heinkel Ag Magnet-induktives Pruefverfahren zur Feststellung von Fehlern im Innern von Stangen
US3469440A (en) * 1966-04-04 1969-09-30 Asea Ab Stress measuring device
US3495166A (en) * 1967-04-10 1970-02-10 Magnaflux Corp Eddy current crack detector systems using crossed coils
US3593120A (en) * 1969-06-03 1971-07-13 Republic Steel Corp Apparatus movable relative to an article for carrying a testing probe at the surface of the article

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1893074A (en) * 1929-06-18 1933-01-03 Sperry Prod Inc Flaw detector
DE847661C (de) * 1943-11-14 1952-08-25 Ernst Heinkel Ag Magnet-induktives Pruefverfahren zur Feststellung von Fehlern im Innern von Stangen
US3469440A (en) * 1966-04-04 1969-09-30 Asea Ab Stress measuring device
US3495166A (en) * 1967-04-10 1970-02-10 Magnaflux Corp Eddy current crack detector systems using crossed coils
US3593120A (en) * 1969-06-03 1971-07-13 Republic Steel Corp Apparatus movable relative to an article for carrying a testing probe at the surface of the article

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4379261A (en) * 1980-09-10 1983-04-05 Lakin Kenneth M Rotating magnetic field device for detecting cracks in metal
EP0090190A1 (de) * 1982-03-22 1983-10-05 Mecapec S.A. Verfahren und Einrichtung zur magnetischen Materialfehlerdetektion
WO1993023751A1 (de) * 1992-05-08 1993-11-25 Tiede Gmbh + Co Rissprüfanlagen Vorrichtung zur magnetischen rissprüfung von ferromagnetischen werkstücken
GB2328509A (en) * 1997-08-20 1999-02-24 Jonathan Roger Max Johnson Magnetic particle inspection apparatus
US6316845B1 (en) 1999-11-05 2001-11-13 Parker Research Corporation Battery powered AC electromagnetic yoke for magnetic particle inspection
US6400146B1 (en) 2000-09-12 2002-06-04 Her Majesty The Queen In Right Of Canada As Represented By The Ministry Of Natural Resources Sensor head for ACFM based crack detection
DE102008016255A1 (de) * 2008-03-29 2009-10-01 Illinois Tool Works Inc., Glenview Vorrichtung zur zerstörungsfreien Prüfung ferromagnetischer Werkstücke
WO2009123847A1 (en) * 2008-03-29 2009-10-08 Illinois Tool Works Inc. Apparatus and method for non-destructive testing of ferromagnetic workpieces
WO2010045765A1 (zh) * 2008-10-24 2010-04-29 捷特（北京）探伤设备有限公司 伸缩式交叉磁轭荧光磁粉探伤机
CN101435797B (zh) * 2008-10-24 2011-04-13 捷特（北京）探伤设备有限公司 伸缩式交叉磁轭荧光磁粉探伤机
CN102087245A (zh) * 2010-12-04 2011-06-08 南昌航空大学 基于非晶合金的电磁检测传感器
CN102087245B (zh) * 2010-12-04 2012-09-19 南昌航空大学 基于非晶合金的电磁检测传感器
WO2012158294A1 (en) * 2011-05-17 2012-11-22 Siemens Energy, Inc. Multi directional electromagnetic yoke for inspection of bores
RU2550760C1 (ru) * 2011-05-17 2015-05-10 Сименс Энерджи, Инк. Многонаправленное электромагнитное ярмо для обследования каналов
CN103547917A (zh) * 2011-05-17 2014-01-29 西门子能量股份有限公司 用于检查孔的多方向电磁轭
US8823369B2 (en) 2011-05-17 2014-09-02 Siemens Energy, Inc. Multi directional electromagnetic yoke for inspection of bores
AU2012256296B2 (en) * 2011-05-17 2014-09-11 Siemens Energy, Inc. Multi directional electromagnetic yoke for inspection of bores
WO2015123023A1 (en) * 2014-02-13 2015-08-20 Siemens Energy, Inc. Multidirectional magnetic particle inspection system
US20150228392A1 (en) * 2014-02-13 2015-08-13 Siemens Energy, Inc. Multidirectional magnetic particle inspection system
US9349516B2 (en) * 2014-02-13 2016-05-24 Siemens Energy, Inc. Multidirectional magnetic particle inspection system
CN103954684A (zh) * 2014-04-23 2014-07-30 厦门大学 一种利用漏磁变化率进行无损检测的方法
CN103954684B (zh) * 2014-04-23 2016-07-06 厦门大学 一种利用漏磁变化率进行无损检测的方法
CN109975388A (zh) * 2017-12-27 2019-07-05 核动力运行研究所 一种基于核电站薄板平面t型焊缝的电磁检测探头
WO2020047849A1 (zh) * 2018-09-07 2020-03-12 中国电建集团山东电力建设第一工程有限公司 一种t型焊接接头检测用交叉电磁轭
CN114034415A (zh) * 2021-10-26 2022-02-11 成都飞机工业（集团）有限责任公司 一种应力检测方法
CN114034415B (zh) * 2021-10-26 2022-09-20 成都飞机工业（集团）有限责任公司 一种应力检测方法

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Publication number Publication date
DE2346999A1 (de) 1974-04-11
JPS4952688A (enrdf_load_stackoverflow) 1974-05-22

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