1、Designation: E3044/E3044M 161Standard Practice forUltrasonic Testing of Polyethylene Butt Fusion Joints1This standard is issued under the fixed designation E3044/E3044M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of l
2、ast revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTESubsection 5.2 corrected editorially in September 2016.1. Scope1.1 This standard practice establishes procedures for ultra-son
3、ic testing (UT) of butt fusion joints in polyethylene pipe.Although high density polyethylene (HDPE) and mediumdensity polyethylene (MDPE) materials are most commonlyused, the procedures described may apply to other types ofpolyethylene.NOTE 1The notes in this specification are for information only
4、andshall not be considered part of this specification.NOTE 2This standard references HDPE and MDPE for pipe applica-tions as defined by Specification D3350.1.2 This standard practice does not address ultrasonic ex-amination of electrofusion joints (coupling joints), socketjoints, or saddles.1.3 This
5、 practice provides two ultrasonic examination pro-cedures. Each has its own merits and requirements for exami-nation and shall be selected as agreed upon in a contractualdocument.1.3.1 Examination Procedure A, Time of Flight Diffraction(TOFD), uses a pair of probes, one transmitting and the otherrec
6、eiving. The procedure requires access to both sides of thejoint from one surface. Provided that position encoding is used,the procedure can be conducted by semi-automated or auto-mated means that provide recoded imaging.1.3.2 Examination Procedure B, Phased Array UltrasonicTesting (PAUT), uses low v
7、elocity refracting wedges or watergaps to produce angled compression mode pulses. The proce-dure can be applied where access is limited to one side of thejoint from one surface. Provided that position encoding is used,the procedure can be conducted by semi-automated or auto-mated means that provide
8、recoded imaging.1.4 The practice is intended to be used on thicknesses of 9to 60 mm (0.375 to 2.4 in.) and diameters 100 mm (4 in.) andgreater. Greater and lesser thicknesses and lesser diametersmay be tested using this standard practice if the technique canbe demonstrated to provide adequate detect
9、ion on mockups ofthe same wall thickness and geometry.1.5 This practice does not specify acceptance criteria.1.6 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shal
10、l be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.7 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-
11、priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 The following documents form a part of this practice tothe extent specified herein.2.2 ASTM Standards:2D3350 Specification for Polyethylene Plastics Pipe and Fit-ting
12、s MaterialsE494 Practice for Measuring Ultrasonic Velocity in Materi-alsE543 Specification for Agencies Performing NondestructiveTestingE1316 Terminology for Nondestructive ExaminationsE2373 Practice for Use of the Ultrasonic Time of FlightDiffraction (TOFD) TechniqueE2700 Practice for Contact Ultra
13、sonic Testing of WeldsUsing Phased ArraysF2620 Practice for Heat Fusion Joining of Polyethylene Pipeand Fittings2.3 ASNT Standards:3ASNT Practice SNT-TC-1A Personnel Qualification andCertification in Nondestructive Testing1This practice is under the jurisdiction of ASTM Committee E07 on Nonde-struct
14、ive Testing and is the direct responsibility of Subcommittee E07.06 onUltrasonic Method.Current edition approved Aug. 1, 2016. Published August 2016. DOI: 10.1520/E3044_E3044M-16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org.
15、 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.Copyright ASTM International, 100 Ba
16、rr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1ANSI/ASNT-CP-189 Standard for Qualification and Certifi-cation of Nondestructive Testing Personnel2.4 Aerospace Industries Association Document:NAS 410 Certification and Qualification of NondestructiveTesting Personnel42.5
17、 ISO Standard:ISO 9712 Non-Destructive TestingQualification and Cer-tification of NDT Personnel53. Terminology3.1 DefinitionsRelated terminology is defined in Termi-nology E1316.3.2 Definitions of Terms Specific to This Standard:3.2.1 butt-fusion joint, na joint made by holding theprepared squared e
18、nds of two pipes or pipe and fitting againsta heated plate per the conditions of a qualified fusionprocedure, which allows for the ends to be brought togetherafter forming the proper melt, and then allowing the joint tocool while maintaining the appropriate applied force. It isrecommended that fusio
19、n procedures comply with PracticeF2620.3.2.2 cell classification, nfor polyethylene pipe resin, thisis a six digit code and letter describing the primary propertiesthat are considered important in the manufacture of PE piping,in the heat fusion joining of this material, in defining thelong-term perf
20、ormance capabilities and color/UV stability. Theclassification categories are defined in Specification D3350.3.2.3 dimension ratio (DR), nthis is the average outsidepipe diameter divided by the minimum wall thickness.NOTE 3The wall thickness increases when the DR decreases.NOTE 4Standard Dimension R
21、atio (SDR) is anANSI term to describespecific DRs in the series, for example, DR9, DR11, DR17 and others.3.2.4 high density polyethylene (HDPE), na tough,flexible, thermoplastic resin made by polymerizing ethylene,having a density range of 0.940 g/cm3to 0.955 g/cm3perSpecification D3350.3.2.5 materi
22、al designations, na shortened code to identifythe pipe materials short-term and long-term properties.NOTE 5For polyethylene, the “PE-XXXX” material designationrepresents the density (first digit), slow crack growth resistance (seconddigit) and hydrostatic design stress (HDS, last two digits) where S
23、pecifi-cation D3350 is the reference.3.2.6 medium density polyethylene (MDPE), na tough,flexible, thermoplastic resin made by polymerizing ethylene,having density range of 0.926 g/cm3to 0.940 g/cm3perSpecification D3350.4. Summary of Practice4.1 This practice provides a general description of thepro
24、cedures to carry out ultrasonic examination of polyethylenebutt fusion joints in pipeline systems.4.2 This practice uses sound waves to inspect butt fusionjoints of polyethylene pipe in order to identify and size internalfusion joint flaws with the intent to non-destructively assessoverall joint qua
25、lity.4.3 Two procedures are described in this practice that haveprinciples common to those found in Practices E2373 andE2700 where Time of Flight Diffraction and Phased-Arraycontact testing are described.4.4 Examination results using this practice may be used incombination with acceptance criteria b
26、ased on workmanship orfitness for purpose.5. Significance and Use5.1 This practice is intended primarily for the automated orsemi-automated ultrasonic examination of butt fusion jointsused in the construction of polyethylene piping systems.5.2 Polyethylene piping has been used in lieu of steel alloy
27、sin the petrochemical, power, water, gas distribution and miningindustries due to its reliability and resistance to corrosion anderosion. Recently, polyethylene pipe has also been used fornuclear safety-related cooling water applications.5.3 Two ultrasonic techniques have proven useful to provideexa
28、mination of fusion joint integrity; Ultrasonic time-of-flight-diffraction (TOFD) and phased array ultrasonic testing(PAUT). These techniques are often considered complemen-tary but may be used independently of each other. The choiceof the technique used may depend on a variety of parametersincluding
29、 diameter, thickness, surface access, detection capa-bilities near surfaces, and quality level required.5.4 The joining process can be subject to a variety of flawsincluding, but not limited to: lack of fusion, particulatecontamination, inclusions, and voids.5.5 Polyethylene material can have a rang
30、e of acousticcharacteristics that make butt joint examination difficult.Acoustic velocity of the material is similar to that commonlyused for ultrasound wedge materials, making it difficult to usethese materials to achieve appropriate refraction of sound at theinterface. Polyethylene materials are h
31、ighly attenuative, whichoften limits the use of higher ultrasonic frequencies. It alsoexhibits a natural high frequency filtering effect.An example ofthe range of acoustic characteristics is provided in Table 1. Thetable notes the wide range of acoustic velocities reported in theliterature. This mak
32、es it essential that the reference blocks aremade of the same cell classification as that examined. Thisshall be confirmed by measuring the acoustic velocity of thepipe being examined. When using PAUT as the examination4Available from Aerospace Industries Association (AIA), 1000 Wilson Blvd.,Suite 1
33、700, Arlington, VA 22209, http:/www.aia-aerospace.org.5Available from International Organization for Standardization (ISO), ISOCentral Secretariat, BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier,Geneva, Switzerland, http:/www.iso.org.TABLE 1 Polyethylene Velocity and AttenuationACompression M
34、odeVelocity (m/s) (in./s)Attenuation 2 MHz(dB/mm) (dB/in.)Attenuation 5 MHz(dB/mm) (dB/in.)2100 to 2670(0.082 to 0.105)0.6to1.5(15.2 to 38)1.1to2.3(27.9 to 58)AA range of velocity and attenuation values have been noted in the literature (1-9).The boldface numbers in parentheses refer to the list of
35、references at the end ofthis standard.E3044/E3044M 1612technique, the acoustic velocity of the reference block shall bewithin 650 m/s of the examined pipe material being examined.5.6 Polyethylene is reported to have a shear velocity of 987m/s. However, due to extremely high attenuation in shear mode
36、(on the order of 5 dB/mm (127 dB/inch) at 2 MHz) no practicalexaminations are carried out using shear mode (6).65.7 Due to the wide range of applications, joint acceptancecriteria for polyethylene pipe are usually project-specific.5.8 A typical butt fusion joint in polyethylene pipe has apronounced
37、bead profile similar to that illustrated in Fig. 1where the bead is shown on the outer and inner surface of thepipe.5.9 TOFD, when used on polyethylene, is simplified in thatmode-converted signals are virtually eliminated due to the highattenuation of the shear mode. However, the near surface andfar
38、 surface dead zones associated with TOFD may be consid-ered limitations if determined to be excessive for the detectionrequirements.5.10 PAUT can be used to address the near surface deadzone that occurs with TOFD.6. Basis of Application6.1 The following items are subject to contractual agree-ment be
39、tween the parties using or referencing this standard.6.2 Personnel QualificationIf specified in the contractualagreement, personnel performing examinations to this standardshall be qualified in accordance with a nationally or interna-tionally recognized NDT personnel qualification practice orstandar
40、d such asANSI/ASNT-CP-189, SNT-TC-1A, NAS-410,ISO 9712, or a similar document and certified by the employeror certifying agency, as applicable. The practice or standardused and its applicable revision shall be identified in thecontractual agreement between the using parties.6.3 Qualification of Nond
41、estructive AgenciesIf specifiedin the contractual agreement, NDT agencies shall be qualifiedand evaluated as described in Specification E543. The appli-cable edition of E543 shall be specified in the contractualagreement.6.4 Procedures and TechniquesThe procedures and tech-niques to be used shall be
42、 as specified in the contractualagreement.6.5 Surface PreparationThe pre-examination surfacepreparation shall be in accordance with paragraph 7.3.11 and7.5.8 unless otherwise specified.6.6 Timing of ExaminationThe timing of the examinationshall be in accordance with Section 8 unless otherwise speci-
43、fied.6.7 Extent of ExaminationThe extent of examination shallinclude the volume of the joint 10 mm (38 in.), as a minimum,either side of the fusion line unless otherwise specified in thecontract.6.8 Reporting CriteriaReporting criteria for the examina-tion results shall be in accordance with Section
44、 8 unlessotherwise specified. Since acceptance criteria are not specifiedin this standard, they shall be specified in the contractualagreement.6.9 Re-examination of Repaired/Reworked ItemsRe-examination of repaired/reworked items is not addressed in thisstandard and if required shall be specified in
45、 the contractualagreement.7. Apparatus and Procedures7.1 Electronic Instruments and Probes:7.1.1 The type of instrument(s) used for the examinationsspecified in Section 7 shall conform to the requirements ofPractices E2373 and E2700 as applicable.7.1.2 Probes used shall produce pulses with two to th
46、reecycles with a nominal center frequency in the range of 1 MHzto 5 MHz. Refracting wedges should be of a low acousticvelocity and low attenuation material so as to produce apositive refraction relative to the angle of incidence. Water-gaptechniques may be suitable to achieve these conditions.7.1.3
47、Wedges shall be contoured to match the pipe curvaturewhen the gap between the wedge and pipe exceeds 0.5 mm(0.02 in.). This is typically required when examining pipe withdiameters less than 500 mm (20 in.).7.2 Standardization Blocks and Other Equipment:7.2.1 Mechanics:7.2.1.1 Mechanical holders shal
48、l be used to ensure thatprobe spacing is maintained at a fixed distance from the jointcenterline. The mechanical holders shall also ensure thatalignment to the intended scan axis on the examination piece ismaintained to a tolerance agreed upon between contractingparties.7.2.1.2 Probe motion may be a
49、chieved using motorized ormanual means but in all cases, the mechanical holder for theprobes shall be equipped with a positional encoder that issynchronized with the sampling of A-scans. Data acquisitionshall not exceed 1 mm (0.04 in.) per A-scan sample for pipe6The boldface numbers in parentheses refer to a list of references at the end ofthis standard.FIG. 1 Typical Bead Profile for Polyethylene Butt Fusion JointE3044/E3044M 1613diameters up to 500 mm (20 in.) and shall not exceed 2 mm(0.08 in.) per A-scan sample for pipe diameters greater than500
