1、Designation: E3022 18Standard Practice forMeasurement of Emission Characteristics andRequirements for LED UV-A Lamps Used in FluorescentPenetrant and Magnetic Particle Testing1This standard is issued under the fixed designation E3022; the number immediately following the designation indicates the ye
2、ar 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. Scope1.1 This practice covers the procedures for testing theper
3、formance of ultraviolet A (UV-A), light emitting diode(LED) lamps used in fluorescent penetrant and fluorescentmagnetic particle testing (see Guides E709 and E2297, andPractices E165/E165M, E1208, E1209, E1210, E1219, E1417/E1417M and E1444).2This specification also includes report-ing and performan
4、ce requirements for UV-A LED lamps.1.2 These tests are intended to be performed only by themanufacturer to certify performance of specific lamp models(housing, filter, diodes, electronic circuit design, opticalelements, cooling system, and power supply combination) andalso includes limited acceptanc
5、e tests for individual lampsdelivered to the user. This test procedure is not intended to beutilized by the end user.1.3 This practice is only applicable for UV-A LED lampsused in the examination process. This practice is not applicableto mercury vapor, gas-discharge, arc or luminescent (fluores-cen
6、t) lamps or light guides (for example, borescope lightsources).1.4 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.5 This standard does
7、 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, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.6 This internationa
8、l standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committe
9、e.2. Referenced Documents2.1 ASTM Standards:3E165/E165M Practice for Liquid Penetrant Examination forGeneral IndustryE709 Guide for Magnetic Particle TestingE1208 Practice for Fluorescent Liquid Penetrant TestingUsing the Lipophilic Post-Emulsification ProcessE1209 Practice for Fluorescent Liquid Pe
10、netrant TestingUsing the Water-Washable ProcessE1210 Practice for Fluorescent Liquid Penetrant TestingUsing the Hydrophilic Post-Emulsification ProcessE1219 Practice for Fluorescent Liquid Penetrant TestingUsing the Solvent-Removable ProcessE1316 Terminology for Nondestructive ExaminationsE1348 Test
11、 Method for Transmittance and Color by Spec-trophotometry Using Hemispherical GeometryE1417/E1417M Practice for Liquid Penetrant TestingE1444 Practice for Magnetic Particle TestingE2297 Guide for Use of UV-Aand Visible Light Sources andMeters used in the Liquid Penetrant and Magnetic ParticleMethods
12、2.2 Other Standards:4ANSI/ISO/IEC 17025 General Requirements for the Com-petence of Testing and Calibration Laboratories1This test method is under the jurisdiction of ASTM Committee E07 onNondestructive Testing and is the direct responsibility of Subcommittee E07.03 onLiquid Penetrant and Magnetic P
13、article Methods.Current edition approved July 1, 2018. Published July 2018. Originally approvedin 2015. Last previous edition approved in 2015 as E3022-15. DOI: 10.1520/E3022-182The use of LED lamps for penetrant examination may be covered by a patent.Interested parties are invited to submit informa
14、tion regarding the identification ofalternative(s) to this patented item to ASTM International Headquarters. Yourcomments will receive careful consideration at a meeting of the responsibletechnical committee, which you may attend.NOTE: ASTM International takes no position respecting the validity of
15、any patentrights asserted in connection with any item mentioned in this standard. Users of thisstandard are expressly advised that determination of the validity of any such patentrights, and the risk of infringement of such rights, are entirely their ownresponsibility.3For referenced ASTM standards,
16、 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 from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New
17、York, NY 10036, http:/www.ansi.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Pri
18、nciples for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1ANSI/NCSL Z540.3 Requirements for the Calibration ofMeasuring and Test Equipment3. Terminology3.1 DefinitionsGeneral terms pertaining
19、to ultraviolet A(UV-A) radiation and visible light used in liquid penetrant andmagnetic examination are defined in Terminology E1316 andshall apply to the terms used in this practice.3.2 Definitions of Terms Specific to This Standard:3.2.1 battery-powered hand-held lamp, nlamp poweredby a battery us
20、ed in either stationary or portable applicationswhere line power is not available or convenient.3.2.1.1 DiscussionThese lamps may also have the optionto be line-powered (that is, alternating current power supply).Smaller lamps, often referred to as “flashlights” or “torches”are used for portable exa
21、mination of focused zones and oftenhave a single LED.3.2.2 current ripple, nunwanted residual periodic varia-tion (spikes or surges) of the constant current that drives theLED at a constant power level.3.2.2.1 DiscussionRipple is due to incomplete suppres-sion of DC (peak to peak) variance resulting
22、 from the powersupply, stability of regulation circuitry, circuit design, andquality of the electronic components.3.2.3 excitation irradiance, nirradiance calculated in therange of 347 nm and 382 nm. This corresponds to the range ofwavelengths that effectively excite fluorescent penetrant dyes(i.e.
23、greater than 80% of relative peak excitation).3.2.4 irradiance, E, nradiant flux (power) per unit areaincident on a given surface. Typically measured in units ofmicro-watts per square centimeter (W/cm2).3.2.5 lamp model, nA lamp with specific design. Anychange to the lamp design requires a change in
24、 modeldesignation and complete qualification of the new model.3.2.6 light-emitting diode, LED, nsolid state electronicdevices consisting of a semiconductor or semiconductor ele-ments that emit radiation or light when powered by a current.3.2.6.1 DiscussionLEDs emit a relatively narrow band-width spe
25、ctrum when a specific current flows through the chip.The emitted wavelengths are determined by the semiconductormaterial and the doping. The intensity and wavelength canchange depending on the current, age, and chip temperature.3.2.7 line-powered lamp, ncorded hand-held or overheadlamps that are lin
26、e-powered and typically used for stationaryinspections within a controlled production environment.3.2.7.1 DiscussionThese lamps are used for examinationof both small and large inspection zones and consist of an LEDarray. Overhead lamps are used in a stationary inspection boothto flood the inspection
27、 area with UV-A radiation. Handheldlamps are used to flood smaller regions with UV-A radiationand can also be used in portable applications where line poweris available.3.2.8 minimum working distance, nthe distance from theinspection surface where the lamp beam profile begins toexhibit non-uniformit
28、y.3.2.9 transmittance, ratio of the radiant flux transmittedthrough a body to that incident upon it.4. Significance and Use4.1 UV-A lamps are used in fluorescent penetrant andmagnetic particle examination processes to excite fluorophores(dyes or pigments) to maximize the contrast and detection ofdis
29、continuities. The fluorescent dyes/pigments absorb energyfrom the UV-A radiation and re-emit visible light whenreverting to its ground state. This excitation energy conversionallows fluorescence to be observed by the human eye.4.2 The emitted spectra of UV-A lamps can greatly affectthe efficiency of
30、 dye/pigment fluorescent excitation.4.3 Some high-intensity UV-Alamps can produce irradiancegreater than 10 000 W/cm2at 15 in. (381 mm). All high-intensity UV-A light sources can cause fluorescent dye fadeand increase exposure of the inspectors unprotected eyes andskin to high levels of damaging rad
31、iation.4.4 UV-A lamps can emit unwanted visible light and harm-ful UV radiation if not properly filtered. Visible light contami-nation above 400 nm can interfere with the inspection processand must be controlled to minimize reflected glare and maxi-mize the contrast of the indication. UV-B and UV-C
32、contami-nation must also be eliminated to prevent exposure to harmfulradiation.4.5 Pulse Width Modulation (PWM) and Pulse Firing (PF)of UV-A LED circuits are not permitted.NOTE 1The ability of existing UV-A radiometers and spectroradiom-eters to accurately measure the irradiance of pulse width modul
33、ated orpulsed fired LEDs and the effect of pulsed firing on indication detectabilityis not well understood.5. Classifications5.1 LED UV-A lamps used for nondestructive testing shallbe of the following types:5.1.1 Type ALine-powered lamps (LED arrays for hand-held and overhead applications) (3.2.5 an
34、d 3.2.6).5.1.2 Type BBattery powered hand-held lamps (LED ar-rays for stationary and portable applications) (3.2.1).5.1.3 Type CBattery powered, handheld lamps (singleLED flashlight or torch for special applications) (3.2.1, Dis-cussion).6. Apparatus6.1 UV-A Radiometer, designed for measuring the ir
35、radianceof electromagnetic radiation. UV-A radiometers use a filter andsensor system to produce a bell-shaped (i.e. Gaussian) responseat 365 nm (3650 ) or top-hat responsivity centered near365 nm (3650 ). 365 nm (3650 ) is the peak wavelengthwhere most penetrant fluorescent dyes exhibit the greatest
36、fluorescence. Ultraviolet radiometers shall be calibrated inaccordance with ANSI/ISO/IEC 17025, ANSI/NCSL Z540.3,or equivalent. Radiometers shall be digital and provide aresolution of at least 5 W/cm2. The sensor front end aperturewidth or diameter shall not be greater than 0.5 in. (12.7 mm).NOTE 2
37、Photometers or visible light meters are not consideredadequate for measuring the visible emission of UV-A lamps whichE3022 182generally have wavelengths in the 400 nm to 450 nm range.6.2 Spectroradiometer, designed to measure the spectralirradiance and absolute irradiance of electromagnetic emission
38、sources. Measurement of spectral irradiance requires that suchinstruments be coupled to an integrating sphere or cosinecorrector. This spectroradiometer shall have a resolution of atleast 0.5 nm and a minimum signal-to-noise ratio of 50:1. Thesystem shall be capable of measuring absolute spectral ir
39、radi-ance over a minimum range of 300 to 400 nm.6.2.1 The system shall be calibrated using emission sourcereference standards.6.3 Spectrophotometer, designed to measure transmittanceor color coordinates of transmitting specimens. The systemshall be able to perform a measurement of regular spectraltr
40、ansmittance over a minimum range of 300 to 800 nm.7. Test Requirements7.1 Lamp models used for nondestructive testing (NDT)shall be tested in accordance with the requirements of Table 1.7.2 LEDs of UV-A Lamps shall be continuously poweredwith the LED drive current exhibiting minimum ripple (see7.6.5
41、). The projected beam shall also not exhibit any perceiv-able variability in projected beam intensity (i.e. strobing,flicker, etc.) (see 7.4.6).7.3 Maximum IrradianceFixture the UV-A lamp 15 60.25 in (381 6 6 mm) above the surface of a flat, levelworkbench with the projected beam orthogonal to the w
42、ork-bench surface. The lamp face shall be parallel to the benchwithin 60.25 in. (66 mm). Ensure that battery-powered lamps(Types B and C) are fully charged. Turn on the lamp and allowto stabilize for 5 min. Place a UV-A radiometer, conforming to6.1, on the workbench. Adjust the lamp position such th
43、at thefilter of the lamp is 15.0 6 0.25 in. (381 6 12.7 mm) from theradiometer sensor. Scan the radiometer across the projectedbeam in two orthogonal directions to locate the point ofmaximum irradiance. Record the maximum irradiance value.7.4 Beam Irradiance ProfileAffix the UV-A lamp abovethe surfa
44、ce of a flat, workbench with the projected beamorthogonal to the workbench surface.7.4.1 Type A lamps shall be supplied with alternatingcurrent (ac) power supply at the manufacturers rated powerrequirement. Power conditioning shall be used to ensure astable power supply free of voltage spikes, rippl
45、es, or surgesfrom the power supply network.7.4.2 Type B and C lamps shall be powered using a constantvoltage power direct current (DC) supply that provides con-stant DC power at the rated, fully charged battery voltage60.5 V.7.4.3 The UV-A lamp shall be turned on and allowed tostabilize for a minimu
46、m of 30 min before taking measure-ments.7.4.4 Place the UV-A radiometer on the workbench. Adjustthe lamp position such that the face of the lamp is 15.0 60.25 in. (381 6 6 mm) from the radiometer sensor. Scan theradiometer across the projected beam in two orthogonaldirections to locate the point of
47、maximum irradiance. Recordthis location as the zero point. Using a 0.5-in. (12.7-mm) grid,translate the radiometer across the projected beam in 0.5-in.(12.7-mm) increments to generate a two-dimensional (2-D)plot of the beam profile (irradiance versus position). Positionthe radiometer using either an
48、 x-y scanner or by manuallyscanning. When manually scanning, use a sheet with 0.5-in.(1.27-cm) or finer squares and record the irradiance value inthe center of each square. The beam irradiance profile shallextend to the point at which the irradiance drops below200 W cm2.7.4.5 Generate and report the
49、 2-D plot of the beam irradi-ance profile (see Fig. 1). Map the range of irradiance from 200to 1000 W/cm2, 1000 to 5000 W/cm2, 5000 to 10 000W/cm2, 10 000 W cm2. Report the minimum beam diam-eter at 1000 and 200 W/cm2.NOTE 3The defined ranges are minimums. Additional ranges arepermitted.7.4.6 During the observations of 7.4.1 through 7.4.5, noteany output power variations indicated by perceived changes inprojected beam intensity, flicker, or strobing. Any variations inobserved beam intensity, flicker, or strobing are unacceptable.7.5 Minimum Work
