ASTM_E_1571_-_11.pdf

Designation:E157111Standard Practice forElectromagnetic Examination of Ferromagnetic Steel WireRope1This standard is issued under the fixed designation E1571;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This practice covers the application and standardizationof instruments that use the electromagnetic,the magnetic flux,and the 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 UnitsThe values stated in inch-pound units are to beregarded as standard.The values given in parentheses aremathematical conversions to SI units are provided for infor-mation only and are not considered standard.1.3 This 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 Documents2.1 ASTM Standards:2E543 Specification for Agencies Performing NondestructiveTestingE1316 Terminology for Nondestructive Examinations2.2 Other Documents:ANSI/ASNT-CP-189 ASNT Standard for Qualification andCertification of Nondestructive Testing Personnel3SNT-TC-1A Recommended Practice for Personnel Qualifi-cation and Certification in Nondestructive Testing3NAS-410 Certification and Qualification of NondestructivePersonnel(Quality Assurance Committee)43.Terminology3.1 DefinitionsFor definitions of terms used in thispractice,refer to Terminology E1316.3.2 Definitions of Terms Specific 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 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 relativemeasure of the amount of material(mass)missing 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 metalliccross-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 Direct Current and Permanent Magnet(MagneticFlux)InstrumentsDirect current(dc)and permanent magnetinstruments(Figs.1 and 2)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 by any other appropriate device that canmeasure absolute magnetic fields or variations in a steady1This 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.1,2011.Published January 2012.Originallypublished as E1571 93.Last previous edition E1571 06.DOI:10.1520/E1571-11.2For 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 fromAmerican 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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 magnetic 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 influence of the magnetizing circuit.This type ofinstrument measures changes in metallic cross-sectional area.4.1.2 Magnetic Flux Leakage InstrumentA direct currentor permanent magnet instrument(Fig.3)is used to supply aconstant f