1、Designation: E114 10E114 15Standard Practice forUltrasonic Pulse-Echo Straight-Beam Contact Testing1This standard is issued under the fixed designation E114; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision
2、. 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 practice2 covers ultrasonic examination
3、 of materials by the pulse-echo method using straight-beam longitudinal wavesintroduced by direct contact of the search unit with the material being examined.1.2 This practice shall be applicable to development of an examination procedure agreed upon by the users of the document.1.3 The values state
4、d in inch-pound units are to be regarded as standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information only and are not considered standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its u
5、se. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:3E317 Practice for Evaluating Performance Characteristics of Ultrasonic Pulse-
6、EchoTesting Instruments and Systems without theUse of Electronic Measurement InstrumentsE543 Specification for Agencies Performing Nondestructive TestingE1316 Terminology for Nondestructive Examinations2.2 ASNT Standards:4SNT-TC-1A Recommended Practice for Personnel Qualification and Certification i
7、n Nondestructive TestingANSI/ASNT CP-189 ASNT Standard for Qualification and Certification of Nondestructive Testing Personnel2.3 Other Documents:5NAS-410 Certification and Qualification of Nondestructive Test Personnel2.4 ISO Standard:6ISO 9712 Non-Destructive TestingQualificaiton and Certification
8、 of NDT Personnel3. Terminology3.1 Refer to Terminology E1316 for definitions of terms used in this practice.4. Basis of Application4.1 Purchaser-Supplier Agreements: The following items require agreement between the using parties for this practice to beused effectively:4.1.1 Qualification of Nondes
9、tructive Testing AgenciesAgreement is required as to whether the nondestructive testing agency,as defined in Specification E543 must be formally evaluated and qualified to perform the examination. If such evaluation andqualification is specified, a documented procedure such as Specification E543 sha
10、ll be used as the basis for evaluation.1 This practice is under the jurisdiction ofASTM Committee E07 on Nondestructive Testing and is the direct responsibility of Subcommittee E07.06 on Ultrasonic Method.Current edition approved June 15, 2010Dec. 1, 2015. Published July 2010December 2015. Originall
11、y approved in 1955. Last previous edition approved in 20052010 asE114 - 95 (2005).E114 - 10. DOI: 10.1520/E0114-10.10.1520/E0114-15.2 For ASME Boiler and Pressure Vessel Code applications see related Practice SE-114 in Section II of that Code.3 For referencedASTM standards, visit theASTM website, ww
12、w.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4 Available from American Society for Nondestructive Testing (ASNT), P.O. Box 28518, 1711 Arlingate Ln., Columbus, OH
13、43228-0518, http:/www.asnt.org.5 Available from Aerospace Industries Association of America, Inc. (AIA), 1000 Wilson Blvd., Suite 1700, Arlington, VA 22209-3928, http:/www.aia-aerospace.org.6 Available from International Organization for Standardization (ISO), ISO Central Secretariat, BIBC II, Chemi
14、n de Blandonnet 8, CP 401, 1214 Vernier, Geneva,Switzerland, http:/www.iso.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequat
15、ely depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM Int
16、ernational, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.1.2 Personnel QualificationNondestructive testing (NDT) personnel shall be qualified in accordance with a nationallyrecognized NDT personnel qualification practice or standard such as ANSI/ASNT CP-189,
17、SNT-TC-1A, NAS-410, ISO 9712, ora similar document. The practice or standard used and its applicable revision shall be specified in the contractual agreementbetween the using parties.4.1.3 Extent of ExaminationThe extent of the examination shall be determined by agreement of the using parties.4.1.4
18、Time of ExaminationThe time of examination shall be determined by agreement of the using parties.4.1.5 Interpretation CriteriaThe criteria by which the ultrasonic signals and part acceptability will be evaluated and shall bedetermined by agreement of the using parties.5. Significance and Use5.1 This
19、 practice employs the use of normal-incident, or straight beam, longitudinal wave ultrasound for the detection andevaluation of discontinuities in materials requiring volumetric examination.5.2 Although not all requirements of this practice can be applied universally to all inspection situations and
20、 materials, it doesprovide the basis for establishing contractual criteria between suppliers and purchasers of materials for performing contactlongitudinal wave pulse-echo examination and may be used as a guide for writing detailed procedures for particular applications.5.3 Types of information that
21、 may be obtained from the pulsed-echo straight-beam practice are as follows:5.3.1 Apparent discontinuity size (see Note 1) by comparison of the signal amplitudes from the test piece to the amplitudesobtained from a reference standard.5.3.2 Depth location of discontinuities by calibrating the horizon
22、tal scale of the A-scan display.5.3.3 Material properties as indicated by the relative sound attenuation or velocity changes of compared items.5.3.4 The extent of bond and unbond (or fusion and lack of fusion) between two ultrasonic conducting materials if geometryand materials permit.NOTE 1The term
23、 “apparent” is emphasized since true size depends on orientation, composition, and geometry of the discontinuity and equipmentlimitations.6. Apparatus6.1 Complete ultrasonic apparatus shall include the following:6.1.1 InstrumentationThe ultrasonic instrument shall be capable of generating, receiving
24、, and amplifying high-frequencyelectrical pulses at such frequencies and energy levels required to perform a meaningful examination and to provide a suitablereadout.6.1.2 Search UnitsThe ultrasonic search units shall be capable of transmitting and receiving ultrasound in the material at therequired
25、frequencies and energy levels necessary for discontinuity detection. Typical search unit sizes usually range from 18 in.(3.2 mm) in diameter to 118 in. (28.6 mm) in diameter with both smaller and larger sizes available for specific applications. Searchunits may be fitted with special shoes for appro
26、priate applications. Special search units encompassing both a transmitter and areceiver as separate piezoelectric elements can be utilized to provide some degree of improved resolution near the examinationsurface.6.1.3 CouplantAcouplant, usually a liquid or semi-liquid, is required between the face
27、of the search unit and the examinationsurface to permit or improve the transmittance of ultrasound from the search unit into the material under test. Typical couplantsinclude water, cellulose gel, oil, and grease. Corrosion inhibitors or wetting agents or both may be used. Couplants must be selected
28、that are not detrimental to the product or the process. The couplant used in standardization should be used for the examination.During the performance of a contact ultrasonic examination, the couplant layer between search unit and examination material mustbe maintained such that the contact area is
29、held constant while maintaining adequate couplant thickness. Lack of couplant reducingthe effective contact area or excess couplant thickness will reduce the amount of energy transferred between the search unit andthe examination piece. These couplant variations in turn result in examination sensiti
30、vity variations.6.1.3.1 The couplant should be selected so that its viscosity is appropriate for the surface finish of the material to be examined.The examination of rough surfaces generally requires a high-viscosity couplant. The temperature of the materials surface canchange the couplants viscosit
31、y. As an example, in the case of oil and greases, see Table 1.6.1.3.2 At elevated temperatures as conditions warrant, heat-resistant coupling materials such as silicone oils, gels, or greasesshould be used. Further, intermittent contact of the search unit with the surface or auxiliary cooling of the
32、 search unit may benecessary to avoid temperature changes that affect the ultrasonic wave characteristics of the search unit. At higher temperatures,certain couplants based on inorganic salts or thermoplastic organic materials, high-temperature delay materials, and search unitsthat are not damaged b
33、y high temperatures may be required.6.1.3.3 Where constant coupling over large areas is needed, as in automated examination, or where severe changes in surfaceroughness are found, other couplants such as liquid gap coupling will usually provide a better examination. In this case, the searchunit does
34、 not contact the examination surface but is separated by a distance of about 0.2 in. (0.5(5.1 mm) filled with couplant.Liquid flowing through the search unit fills the gap. The flowing liquid provides the coupling path and has the additional advantageof cooling the search unit if the examination sur
35、face is hot.E114 1526.1.3.4 An alternative means of direct contact coupling is provided by the wheel search unit. The search unit is mounted at therequired angle to a stationary axle about which rotates a liquid-filled flexible tire. A minimum amount of couplant providesultrasonic transmission into
36、the examination surface since the elastic tire material is in rolling contact and conforms closely to thesurface.6.1.4 Reference StandardsThe production item itself may be an adequate standard using the height of the back wall echo forreference. For more quantitative information, machined artificial
37、 reflectors (discontinuities) or charts representing distance-amplitude relationships of known reflector sizes for a particular search unit and material may be used for standardization. Theseartificial reflectors may be in the form of flat-bottom holes, side-drilled holes, or slots. An alternate met
38、hod of fabricating areference standard may be the introduction of known discontinuities during the fabrication process of a production item or otherconvenient configuration. The surface finish of the reference standard should be similar to the surface finish of the production item(or corrected; see
39、7.3). The reference standard material and the production material should be acoustically similar (in velocity andattenuation). The reference standard selected shall be used by the examiner as the basis for signal comparisons.7. Standardization of Apparatus7.1 If quantitative information is to be obt
40、ained, vertical or horizontal linearity or both should be checked in accordance withPractice E317 or another procedure approved by the users of the document. An acceptable linearity performance may be agreedupon by the users of the document.7.2 Prior to examination, standardize the system in accorda
41、nce with the product specification.7.3 Where the surface finishes of the reference standard and the production item do not match, or where there is an acousticdifference between the standard and the production item, an attenuation correction should be made to compensate for thedifference. The attenu
42、ation correction is accomplished by noting the difference between signals received from the same referencereflector (that is, back reflection) in the basic standardization (reference) block and in the production material, and correcting forthis difference.7.4 It should be recognized that near-field
43、effects may cause sensitivity inconsistencies when searching for discontinuitiessmaller than the effective beam diameter. Suitable delay line search units or other means such as examining from both sides of theitem may be considered where the application warrants fine scrutiny. When performing exami
44、nations in the far-field, it isrecommended that compensation be made for the acoustic attenuation of the test material with respect to a certain referencestandard. This compensation may be accomplished with multiple depth reference reflectors, electronically, with attenuation curvesdrawn on the face
45、 of the A-scan display, or with charts for distance-amplitude relationships of known reflectors. For optimumexamination performance, compensations should be made for both near and far-field effects.7.5 Unless otherwise specified, the initial pulse and at least one back reflection shall appear on the
46、 A-scan display whileexamining for discontinuities in materials having parallel surfaces. The total number of back reflections depends upon equipment,geometry and material type, information desired, or operator preference. Reduction of the back reflection during scanning isindicative of increased at
47、tenuation or sound scattering discontinuities provided that front and back surface roughness andTABLE 1 Suggested ViscositiesOil CouplantsNOTE 1The table is a guide only and is not meant to exclude the useof a particular couplant that is found to work satisfactorily on a particularsurface.Approximat
48、e Surface Roughness Average(Ra), in. (m)Equivalent CouplantViscosity, Weight MotorOil5100 (0.12.5) SAE 1050200 (1.35.1) SAE 20100400 (2.510.2) SAE 30250700 (6.417.8) SAE 40Over 700 (18) cup greaseTABLE 1 Suggested ViscositiesOil CouplantsNOTE 1The table is a guide only and is not meant to exclude th
49、e useof a particular couplant that is found to work satisfactorily on a particularsurface.Approximate Surface Roughness Average(Ra), in. (m)Equivalent CouplantViscosity, Weight MotorOil5100 (0.12.5) SAE 1050200 (1.35.1) SAE 20100400 (2.510.2) SAE 30250700 (6.417.8) SAE 40Over 700 (18) cup greaseE114 153parallelism of the production piece are approximately the same as that of the standard. For non-parallel surfaces, the time traceof the display shall be standardized by using standards that include the maximum thickness of the production i
