1、Designation: E 1571 06Standard Practice forElectromagnetic Examination of Ferromagnetic Steel WireRope1This standard is issued under the fixed designation E 1571; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last rev
2、ision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers the application and standardizationof instruments that use the electromagnetic, the magnetic flux,and th
3、e magnetic flux leakage examination method to detectflaws and changes in metallic cross-sectional areas in ferro-magnetic wire rope products.1.1.1 This practice includes rope diameters up to 2.5 in.(63.5 mm). Larger diameters may be included, subject toagreement by the users of this practice.1.2 Thi
4、s standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Document
5、s2.1 ASTM Standards:2E 543 Specification for Agencies Performing Nondestruc-tive TestingE 1316 Terminology for Nondestructive Examinations2.2 Other Documents:ANSI/ASNT-CP-189 ASNT Standard for Qualification andCertification in Nondestructive Testing Personnel3SNT-TC-1A Recommended Practice for Perso
6、nnel Qualifi-cation and Certification in Nondestructive Testing3NAS-410 Certification and Qualification of NondestructivePersonnel (Quality Assurance Committee)43. Terminology3.1 DefinitionsSee Terminology E 1316 for general ter-minology applicable to this practice.3.2 Definitions of Terms Specific
7、to This Standard:3.2.1 dual-function instrumenta wire rope NDT instru-ment designed to detect and display changes of metalliccross-sectional area on one channel and local flaws on anotherchannel of a dual-channel strip chart recorder or anotherappropriate device.3.2.2 local flaw (LF)a discontinuity
8、in a rope, such as abroken or damaged wire, a corrosion pit on a wire, a grooveworn into a wire, or any other physical condition that degradesthe integrity of the rope in a localized manner.3.2.3 loss of metallic cross-sectional area (LMA)a rela-tive measure of the amount of material (mass) missing
9、from alocation along the wire rope and is measured by comparing apoint with a reference point on the rope that representsmaximum metallic cross-sectional area, as measured with aninstrument.3.2.4 single-function instrumenta wire rope NDT instru-ment designed to detect and display either changes in m
10、etalliccross-sectional area or local flaws, but not both, on a strip chartrecorder or another appropriate device.4. Summary of Practice4.1 The principle of operation of a wire rope nondestructiveexamination instrument is as follows:4.1.1 AC Electromagnetic InstrumentAn electromagneticwire rope exami
11、nation instrument works on the transformerprinciple with primary and secondary coils wound around therope (Fig. 1). The rope acts as the transformer core. Theprimary (exciter) coil is energized with a low frequencyalternating current (ac), typically in the 10 to 30 Hz range. Thesecondary (search) co
12、il measures the magnetic characteristicsof the rope. Any significant change in the magnetic character-istics in the core (wire rope) will be reflected as voltagechanges (amplitude and phase) in the secondary coil. Electro-magnetic instruments operate at relatively low magnetic fieldstrengths; theref
13、ore, it is necessary to completely demagnetize1This practice is under the jurisdiction of ASTM Committee E07 on Nonde-structive Testing and is the direct responsibility of Subcommittee E07.07 onElectromagnetic Method.Current edition approved Dec. 1, 2006. Published January 2007. Originallypublished
14、as E 1571 93. Last previous edition E 1571 01.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from
15、American Society for Nondestructive Testing (ASNT), P.O. Box28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http:/www.asnt.org.4Available from Aerospace Industries Association of America, Inc. (AIA), 1000Wilson Blvd., Suite 1700,Arlington, VA22209-3928, http:/www.aia-aerospace.org.1Copyright AST
16、M International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.the rope before the start of an examination. This type ofinstrument is designed to detect changes in metallic cross-sectional area.4.1.2 Direct Current and Permanent Magnet (MagneticFlux) Instruments
17、Direct current (dc) and permanent magnetinstruments (Figs. 2 and 3) supply a constant flux thatmagnetizes a length of rope as it passes through the sensor head(magnetizing circuit). The total axial magnetic flux in the ropecan be measured either by Hall effect sensors, an encircling(sense) coil, or
18、by any other appropriate device that canmeasure absolute magnetic fields or variations in a steadymagnetic field. The signal from the sensors is electronicallyprocessed, and the output voltage is proportional to the volumeof steel or the change in metallic cross-sectional area, withinthe region of i
19、nfluence of the magnetizing circuit. This type ofinstrument measures changes in metallic cross-sectional area.4.1.3 Magnetic Flux Leakage InstrumentA direct currentor permanent magnet instrument (Fig. 4) is used to supply aconstant flux that magnetizes a length of rope as it passesthrough the sensor
20、 head (magnetizing circuit). The magneticflux leakage created by a discontinuity in the rope, such as abroken wire, can be detected with a differential sensor, such asa Hall effect sensor, sensor coils, or by any appropriate device.The signal from the sensor is electronically processed andrecorded.
21、This type of instrument measures LFs. While theinformation is not quantitative as to the exact nature andmagnitude of the causal flaws, valuable conclusions can bedrawn as to the presence of broken wires, internal corrosion,and fretting of wires in the rope.”4.2 The examination is conducted using on
22、e or more tech-niques discussed in 4.1. Loss of metallic cross-sectional areacan be determined by using an instrument operating accordingto the principle discussed in 4.1.1 and 4.1.2. Broken wires andinternal (or external) corrosion can be detected by using amagnetic flux leakage instrument as descr
23、ibed in 4.1.3. Theexamination procedure must conform to Section 9. One instru-ment may incorporate both magnetic flux and magnetic fluxleakage principles.5. Significance and Use5.1 This practice outlines a procedure to standardize aninstrument and to use the instrument to examine ferromagneticwire r
24、ope products in which the electromagnetic, magneticflux, magnetic flux leakage, or any combination of thesemethods is used. If properly applied, the electromagnetic andthe magnetic flux methods are capable of detecting the pres-ence, location, and magnitude of metal loss from wear andcorrosion, and
25、the magnetic flux leakage method is capable ofdetecting the presence and location of flaws such as brokenwires and corrosion pits.5.2 The instruments response to the ropes fabrication,installation, and in-service-induced flaws can be significantlydifferent from the instruments response to artificial
26、 flaws suchas wire gaps or added wires. For this reason, it is preferable todetect and mark (using set-up standards that represent) realin-service-induced flaws whose characteristics will adverselyaffect the serviceability of the wire rope.FIG. 1 Schematic Representation of an Electromagnetic Instru
27、ment Sensor-HeadFIG. 2 Schematic Representation of a Permanent Magnet Equipped Sensor-Head Using a Sense Coil to Measure the Loss of MetallicCross-Sectional AreaE15710626. Basis of Application6.1 The following items require agreement by the users ofthis practice and should be included in the rope ex
28、aminationcontract:6.1.1 Acceptance criteria.6.1.2 Determination of LMA, or the display of LFs, or both.6.1.3 Extent of rope examination (that is, full length thatmay require several setups or partial length with one setup).6.1.4 Standardization method to be used: wire rope refer-ence standard, rod r
29、eference standards, or a combinationthereof.6.1.5 Maximum time interval between equipment standard-izations.6.2 Personnel QualificationIf specified in the contractualagreement, personnel performing examinations in accordancewith this test method shall be qualified in accordance with anationally or i
30、nternationally recognized NDT personnel quali-fication practice or standard such as ANSI/ASNT CP-189,SNT-TC-1A, NAS-410, or a similar document and certified bythe employer or certifying aagency as applicable. The practiceor standard used and its applicable revision shall be specified inthe contractu
31、al agreement between the using parties.6.3 Qualification of Nondestructive AgenciesIf specifiedin the contractual agreement, NDT agencies shall be qualifiedand evaluated as described in E 543. The applicable edition ofE 543 shall be specified in the contractual agreement.6.4 Wire Rope Reference Stan
32、dard (Fig. 5):6.4.1 Type, dimension, location, and number of artificialanomalies to be placed on a wire rope reference standard.6.4.2 Methods of verifying dimensions of artificial anoma-lies placed on a wire rope reference standard and allowabletolerances.6.4.3 Diameter and construction of wire rope
33、(s) used for awire rope reference standard.6.5 Rod Reference Standards (Fig. 6):6.5.1 Rod reference standard use, whether in the laboratoryor in the field, or both.6.5.2 Quantity, lengths, and diameters of rod referencestandards.7. Limitations7.1 General Limitations:FIG. 3 Schematic Representation o
34、f a Permanent Magnet Equipped Sensor-Head Using Hall Devices to Measure the Loss of MetallicCross-Sectional AreaFIG. 4 Illustration of the Leakage Flux Produced by a Broken WireFIG. 5 Example of a Wire Rope Reference StandardE15710637.1.1 This practice is limited to the examination of ferro-magnetic
35、 steel ropes.7.1.2 It is difficult, if not impossible, to detect flaws at ornear rope terminations and ferromagnetic steel connections.7.1.3 Deterioration of a purely metallurgical nature (brittle-ness, fatigue, etc.) may not be easily distinguishable.7.1.4 A given size sensor head accommodates a li
36、mitedrange of rope diameters, the combination (between ropeoutside diameter and sensor head inside diameter) of whichprovides an acceptable minimum air gap to assure a reliableexamination.7.2 Limitations Inherent in the Use of Electromagnetic andMagnetic Flux Methods:7.2.1 Instruments designed to me
37、asure changes in metalliccross-sectional area are capable of showing changes relative tothat point on the rope where the instrument was standardized.7.2.2 The sensitivity of these methods may decrease withthe depth of the flaw from the surface of the rope and withdecreasing gaps between the ends of
38、the broken wires.7.3 Limitations Inherent in the Use of the Magnetic FluxLeakage Method:7.3.1 It may be impossible to discern relatively small-diameter broken wires, broken wires with small gaps, orindividual broken wires within closely-spaced multiple breaks.It may be impossible to discern broken w
39、ires from wires withcorrosion pits.7.3.2 Because deterioration of a purely metallurgical naturemay not be easily distinguishable, more frequent examinationsmay be necessary after broken wires are detected to determinewhen the rope should be retired, based on percent rate ofincrease of broken wires.8
40、. Apparatus8.1 The equipment used shall be specifically designed toexamine ferromagnetic wire rope products.8.1.1 The energizing unit within the sensor head shallconsist of permanent or electromagnets, or ac or dc solenoidcoils configured to allow application to the rope at the locationof service.8.
41、1.2 The energizing unit, excluding the ac solenoid coil,shall be capable of magnetically saturating the range (size andconstruction) of ropes for which it was designed.8.1.3 The sensor head, containing the energizing and detect-ing units, and other components, should be designed toaccommodate differ
42、ent rope diameters. The rope should beapproximately centered in the sensor head.8.1.4 The instrument should have connectors, or othermeans, for transmitting output signals to strip chart recorders,data recorders, or a multifunction computer interface. Theinstrument may also contain meters, bar indic
43、ators, or otherdisplay devices, necessary for instrument setup, standardiza-tion, and examination.8.1.5 The instrument should have an examination distanceand rope speed output indicating the current examinationdistance traveled and rope speed or, whenever applicable, havea proportional drive chart c
44、ontrol that synchronizes the chartspeed with the rope speed.8.2 Auxiliary EquipmentThe examination results shall be recorded on a permanentbasis by either8.2.1 a strip chart recorder8.2.2 and/or by an other type of data recorder8.2.3 and/or by a multifunctional computer interface.9. Examination Proc
45、edure9.1 The electronic system shall have a pre-examinationstandardization procedure.9.2 The wire rope shall be examined for LFs or LMA, orboth, as specified in the agreement by the users of this practice.The users may select the instrument that best suits the intendedpurpose of the examination. The
46、 examination should be con-ducted as follows:9.2.1 The rope must be demagnetized before examinationby an electromagnetic instrument. If a magnetic flux or amagnetic flux leakage instrument is used, it may be necessaryto repeat the examination to homogenize the magnetization ofthe rope.9.2.2 The sens
47、or head must be approximately centeredaround the wire rope.9.2.3 The instrument must be adjusted in accordance with aprocedure. The sensitivity setting should be verified prior tostarting the examination by inserting a ferromagnetic steel rodor wire of known cross-sectional area. This standardizatio
48、nsignal should be permanently recorded for future reference.9.2.4 The wire rope must be examined by moving the head,or the rope, at a relatively uniform speed. Relevant signal(s)must be recorded on suitable media, such as on a strip chartrecorder, on a tape recorder, or on computer file(s), for thep
49、urpose of both present and future replay/analysis.9.2.5 The following information shall be recorded as exami-nation data for analysis:9.2.5.1 Date of examination,9.2.5.2 Examination number,9.2.5.3 Customer identification,9.2.5.4 Rope identification (use, location, reel and ropenumber, etc.),9.2.5.5 Rope diameter and construction,9.2.5.6 Instrument serial number,9.2.5.7 Instrument standardization settings,9.2.5.8 Strip chart recorder settings,9.2.5.9 Strip chart speed,9.2.5.10 Location of sensor head with respect to a well-defined reference point along the rope, both
