1、Designation: E273 15Standard Practice forUltrasonic Testing of the Weld Zone of Welded Pipe andTubing1This standard is issued under the fixed designation E273; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 This practice2describes general ultrasonic
3、 testing pro-cedures for the detection of discontinuities in the weld andadjacent heat affected zones of welded pipe and tubing byscanning with relative motion between the search unit and pipeor tube. When contact or unfocused immersion search units areemployed, this practice is intended for tubular
4、 products havingspecified outside diameters 2 in. (50 mm) and specified wallthicknesses of18 to 1116 in. (3 to 27 mm). When properlyfocused immersion search units are employed, this practicemay also be applied to material of smaller diameter and thinnerwall.NOTE 1When contact or unfocused immersion
5、search units are used,precautions should be exercised when examining pipes or tubes near thelower specified limits. Certain combinations of search unit size, frequency,thinwall thicknesses, and small diameters could cause generation ofunwanted sound waves that may produce erroneous examination resul
6、ts.1.2 All surfaces of material to be examined in accordancewith this practice shall be clean from scale, dirt, burrs, slag,spatter or other conditions that would interfere with theexamination results. The configuration of the weld must besuch that interfering signals are not generated by reflection
7、sfrom it. Treatment of the inner surface and outer surface weldbeads such as trimming (“scarfing”) or rolling is often requiredto remove protuberances that could result in spurious reflec-tions.1.3 This practice does not establish acceptance criteria, theymust be specified by the using parties.1.4 T
8、he values stated in inch-pound units are to be regardedas the standard. The SI equivalents are in parentheses and maybe approximate.1.5 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 establ
9、ish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3E543 Specification for Agencies Performing NondestructiveTestingE1316 Terminology for Nondestructive Examinations2.2 ASNT Documents:4Recomme
10、nded Practice SNT-TC-1A Personnel Qualifica-tion and Certification in Nondestructive TestingANSI/ASNT CP-189 Standard for Qualification and Certifi-cation of Nondesctructive Testing Personnel2.3 ISO Standard:5ISO 9712 Non-destructive TestingQualification and Cer-tification of NDT Personnel3. Termino
11、logy3.1 DefinitionsFor definitions of terms used in thispractice, see Terminology E1316.4. Summary of Practice4.1 A pulsed ultrasonic angle beam shall be propagated inthe wall of the pipe or tube by either the surface contact orimmersion method. Fig. 1 illustrates the characteristic obliquesound ent
12、ry into the pipe wall for both contact and immersionexamination from one search unit.NOTE 2The immersion examination method may include tanks, wheelsearch units, or bubbler systems.1This practice is under the jurisdiction of ASTM Committee E07 on Nonde-structive Testing and is the direct responsibil
13、ity of Subcommittee E07.06 onUltrasonic Method.Current edition approved June 1, 2015. Published June 2015. Originallyapproved in 1965. Last previous edition approved in 2010 as E273-10. DOI:10.1520/E0273-15.2For ASME Boiler and Pressure Vessel Code applications see related PracticeSE-273 in Section
14、II of that Code.3For 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.4Available fromAmerican Society for Nondestru
15、ctive Testing (ASNT), P.O. Box28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http:/www.asnt.org.5Available from International Organization for Standardization (ISO), 1, ch. dela Voie-Creuse, CP 56, CH-1211 Geneva 20, Switzerland, http:/www.iso.org.*A Summary of Changes section appears at the en
16、d of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.2 The weld line shall be examined from both sides toensure detection of imperfections with a shape or orientationthat produces a preferential direction of reflection.
17、5. Significance and Use5.1 The purpose of this practice is to outline a procedure fordetecting weld discontinuities such as lack of fusion, pin holes,lack of penetration, longitudinal cracks, porosity and inclusionsby the ultrasonic pulse-reflection method.6. Basis of Application6.1 The following it
18、ems are subject to contractual agree-ment between the parties using or referencing this standard.6.2 If specified in the contractual agreement, personnelperforming examinations to this standard shall be qualified inaccordance with a nationally recognized NDT personnel quali-fication practice or stan
19、dard such as ANSI/ASNT-CP-189,SNT-TC-1A, ISO 9712, NAS-410, or a similar document andcertified by the employer or certifying agency, as applicable.The practice or standard used and its applicable revision shallbe identified in the contractual agreement between the usingparties.6.3 Qualification of N
20、ondestructive AgenciesIf specifiedin the contractual agreement, NDT agencies shall be qualifiedand evaluated as described in E543. The applicable edition ofE543 shall be specified in the contractual agreement.6.4 Procedures and TechniquesThe procedures and tech-niques to be utilized shall be as spec
21、ified in the contractualagreement, including:6.4.1 Type, dimension, and number of reference reflectors tobe placed in the reference standard,6.4.2 Standardization of examination sensitivity intervals,6.4.3 Examination frequency,6.4.4 Pulse repetition rate,6.4.5 Sound beam orientation and number of b
22、eams used,and6.4.6 Procedure and use of distance amplitude compensa-tion.6.5 Surface PreparationThe pre-examination surfacepreparation criteria shall be in accordance with paragraph 1.2unless otherwise specified.6.6 Reporting Criteria/Acceptance CriteriaSince accep-tance criteria are not specified i
23、n this standard, they shall bespecified in the contractual agreement.6.7 Reexamination of Repaired/Reworked ItemsReexamination of repaired/reworked items is not addressed inthis standard and if required shall be specified in the contrac-tual agreement.7. Procedure7.1 Apparatus7.1.1 The instruments a
24、nd accessory equipment shall becapable of producing, receiving, amplifying, and displayingelectrical pulses at frequencies and pulse rates deemed neces-sary by the using parties. They shall be capable of distinguish-ing the reference reflectors described in Section 7.2 to theextent required in the s
25、tandardization procedure outlined inSection 7.37.1.2 For pulse echo examination systems, the contact orimmersion search units should produce ultrasonic waves thattravel in the pipe or tube wall at a refracted angle of from 35to 70 and perpendicular to the weld seam. For pitch/catch orthrough transmi
26、ssion examination systems, orientation of theentry sound beam other than perpendicular to the weld seammay be required.7.1.3 CouplantA liquid such as water, oil, glycerin, etc.,capable of conducting ultrasonic vibrations from the searchunit to the pipe or tube shall be used. Rust inhibitors, softene
27、rs,and wetting agents may be added to the couplant. The couplantliquid with all additives should not be detrimental to thesurface condition of the pipe or tubing and should wet thesurface. In examining electric-resistance-welded pipe, water-soluble oil used in cooling the pipe serves as a satisfacto
28、rycouplant.7.1.4 Distance Amplitude CompensationThe use of elec-tronic methods to compensate for attenuation losses as afunction of ultrasonic metal travel distance may be employed.7.1.5 Search UnitsThe search unit must be appropriatelysized with respect to width and beam included angle to achievefu
29、ll wall thickness coverage(1). Where this can not be achievedwith a single search unit propagating in a given direction, twoor more search units may be used to scan in each direction. Theeffective beam length of the search units shall be such thatreliable detection of all reference reflectors is acc
30、omplishedwithout exceeding the “noise” limits of 7.3.2. The focal lengthof focused search units shall be at least equal to the radius ofthe material plus a suitable water path so that initial focus maybe on the tube or pipe central axis (2).7.2 Reference StandardsNOTE 1 = 35 through 70.FIG. 1 Angle
31、Projection of Ultrasonic WaveE273 1527.2.1 A reference standard, of sufficient length to allowverification of system standardization, shall be prepared from alength of pipe or tubing of the same nominal diameter and wallthickness, material, surface finish, and acoustical properties asthe material to
32、 be examined. The pipe or tube selected for thispurpose shall be free of discontinuities or other abnormalconditions that can cause interference with the detection of thereference reflectors. The reference reflectors shall be selectedto ensure uniform coverage of the weld at the sensitivity levelspr
33、escribed. The reference reflectors most commonly used willconsist of machined notches and drilled holes as described inparagraph 7.2.2. All upset metal, burrs, etc., adjacent to thereference reflectors, shall be removed.7.2.1.1 Electric Resistance-Welded, Laser-Welded or Butt-Welded PipeReference re
34、flectors shall be placed in the centerof weld seam and in a line parallel to it unless permission isobtained from the contracting or using agency to place thereference reflectors elsewhere in the reference standard. Whenlongitudinal notches are used as reference reflectors, they shallbe placed on th
35、e outer and inner surfaces of the referencestandard and be separated by a sufficient distance to ensure thatthe response from one reflector does not interfere with thatfrom the other.NOTE 3If reference reflectors are placed in a location other than thecenterline of the weld seam there is no assuranc
36、e that the beam ispenetrating the weld unless adequate signal response is obtained from thesearch units scanning the reflector from both sides of the weld. The loweramplitude of response from the two directions must be used in determin-ing the rejection threshold level. Positioning of automatic alar
37、m gatesmust be such as to respond to the signal from the reference reflector, butalso the signals originating from the reflections from discontinuitiesanywhere in the weld seam itself.7.2.1.2 Fusion-Welded PipeThe reference reflectors shallbe placed in the weld. When longitudinal notches are used as
38、reference reflectors, they shall be placed in the crown of thefusion-weld bead as shown in Fig. 2(a). In fusion-welded pipecontaining both inside and outside surface weld beads, alongitudinal notch reference reflector shall be placed in theweld-bead crown on both the outside and inside surfaces.When
39、 drilled holes are employed, they shall be drilledradially from both the outside and inside surfaces through 50 %of the wall thickness at the weld-bead crown or such otherdepth as agreed upon by the user or contracting agency andseparated by some distance that guarantees a distinct andseparate respo
40、nse from each one (see Fig. 2(c) and Fig. 2(d).By agreement between the purchaser and manufacturer, a holedrilled radially 100 % through the pipe wall may be usedinstead of the 50 % drilled hole (see Fig. 2(e).NOTE 4Fill 50 % deep or through-holes with a waterproof filler suchas bees wax to prevent
41、couplant entry. Otherwise, such entry couldproduce erratic and/or spurious reflections.Additional reflectors may be used to produce signals atreflection times that define weld-zone extremities for thepurpose of establishing alarm gate timing or other means ofcontrolling the examination area. Holes m
42、ay be drilled radially100 % through the pipe wall at the weld-zone edges.7.2.2 The notch dimensions of length, depth, width, and forFig. 3(a) and Fig. 3(b) the included angle shall be decidedupon by the using party or parties. Fig. 3 illustrates thecommonly accepted notch configurations and the dime
43、nsionsto be measured.7.2.2.1 The notch depth (h) shall be measured from theadjacent surface to its maximum and minimum penetration.Measurements may be made by optical, replicating ormechanical, or other techniques. Notch depth is commonlyspecified as a percent of nominal wall thickness with typicalv
44、alues being 10, 1212, or 20 %. A +0/-10 % tolerance isallowable on notch depths.7.2.2.2 The notch length (l) is considered to be the dimen-sion over which the specified depth is maintained.FIG. 2 Typical Notch Locations for Fusion Welded Pipe FIG. 3 Common Reference ReflectorsE273 1537.2.2.3 The wid
45、th (w) of the notch has negligible effect onstandardization and is not a critical dimension.7.3 Standardization of Examination Sensitivity7.3.1 Using the reference standard specified in 7.2, theequipment shall be adjusted to produce readily distinguishedand clearly identifiable indications from both
46、 the inner andouter reference reflectors. The relative response to the innerand outer reflectors shall be as near equal as possible. Thelesser of the two responses shall be used as the acceptancelevel.NOTE 5Adjustment of water path, adjustment of distance (d)inFig.1 and angulation of the beam are us
47、ed to achieve equality. It should benoted however, that detection, or balancing of signals from both outersurface and inner surface notches does not guarantee that examination forradical defects is being achieved throughout the full wall thickness. Toeffect such examination, especially in pipes and
48、tubes with thicker walls,it is necessary that the beam refraction angle and search unit size (beamincluded angle for focused units) be selected to be compatible with theration of diameter-to-wall-thickness of the material as stated in 7.1.5 anddescribed in Reference (1).7.3.2 Instrument sensitivity
49、and scanning systemparameters, such as search unit positioning and scanning,speed, shall be adjusted to produce signal levels that arerepeatable from all reference indicators within the limitsdescribed below. If a strip chart or similar recorder is used, theamplitude stability of all target indications shall be within 10 %of full scale height (FSH) for several successive scans of thereference standard under conditions simulating those that willbe used for the actual material examination. Peak “noise”signal amplitudes observed during scanning over
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