1、Designation: E 1324 00 (Reapproved 2005)Standard Guide forMeasuring Some Electronic Characteristics of UltrasonicExamination Instruments1This standard is issued under the fixed designation E 1324; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、 of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide describes procedures for electronically mea-suring the following performance-rel
3、ated characteristics ofsome sections of ultrasonic instruments:1.1.1 Power Supply Section:line regulation,battery discharge time, andbattery charge time.1.1.2 Pulser Section:pulse shape,pulse amplitude,pulse rise time, pulse length, andpulse frequency spectrum.1.1.3 Receiver Section:vertical lineari
4、ty,frequency response,noise and sensitivity, anddB controls.1.1.4 Time Base Section:horizontal linearity, andclock (pulse repetition rate).1.1.5 Gate/Alarm Section:delay and width,resolution,alarm level,gain uniformity,analog output, andback echo gate.1.2 This guide complements Practice E 317, and i
5、s notintended for evaluating the performance characteristics ofultrasonic examination instruments on the inspection/production line.NOTE 1No access to internal circuity is required.2. Referenced Documents2.1 ASTM Standards:E 317 Practice for Evaluating Performance Characteristicsof Ultrasonic Pulse-
6、Echo Testing Systems Without the Useof Electronic Measurement Instruments2E 1316 Terminology for Nondestructive Examinations22.2 Military Standard:MIL-STD-45662A Calibration System Requirements32.3 Other Standard:IEEE Std. 100, IEEE Standard Dictionary of Electrical andElectronic Terms43. Summary of
7、 Guide3.1 The electronic performance of each section is measuredby identifying that portion of the electrical circuit of theinstrument which comprises the section, applying the recom-mended stimulus or load, or both, and performing the requiredmeasurements using commercially available electronic tes
8、tequipment. These data are then summarized in tabular orgraphical form as performance-related values which can becompared with corresponding values of other ultrasonic exami-nation instruments or of values for the same instrumentobtained earlier (see Section 12 for a suggested reportingformat).3.2 T
9、he following describes the sections of the ultrasonicinstrument and their interrelations during measurement:3.2.1 Power Supply SectionThe power supply section isthat portion of the total instrument circuitry which supplies theregulated DC voltages required to power all other sections ofthe ultrasoni
10、c instrument, including the high voltage (that is,pulser and CRT voltage) circuitry.3.2.2 Pulser SectionThe pulser section is that portion ofthe total instrument circuitry which generates the electrical1This guide is under the jurisdiction of ASTM Committee E07 on Nondestruc-tive Testing and is the
11、direct responsibility of Subcommittee E07.06 on UltrasonicMethod.Current edition approved January 1, 2005. Published January 2005. Originallyapproved in 1990. Last previous edition approved in 2000 as E 1324 - 00.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Cu
12、stomer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.4Available from I
13、nstitute of Electrical and Electronics Engineers, Inc. (IEEE),445 Hoes Ln., P.O. Box 1331, Piscataway, NJ 08854-13311Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.pulse used to energize the ultrasonic search unit. The pulsersection
14、may also include the pulse-shape modification controlssuch as pulse length, damping, or tuning controls.3.2.3 Receiver SectionThe receiver section is that portionof the total instrument circuitry which amplifies, or modifies, orboth, the radio frequency (RF) pulses received from theultrasonic search
15、 unit. This includes the RF amplifiers, detec-tors, video amplifiers, suppression and filtering, and the CRTvertical deflection circuits. Some instruments may not containall of these circuits.3.2.3.1 Time Variable Gain (TVG), (alternatively referred toas Distance Amplitude Correction (DAC), Time Con
16、trolledGain (TCG), etc.) and reject or threshold, while part of thereceiver section, should be turned off while making measure-ments unless otherwise specified by the user.3.2.4 Gate/Alarm SectionThis section monitors the sig-nals in the receiver section to detect the presence or absence ofsignifica
17、nt indications. The gate may include attenuation orgain controls. This section is considered separate from thereceiver section for the purposes of this guide. The alarm signalmay be audible, a voltage proportional to the indicationamplitude, or a mark on voltage or current sensitive paper orsome com
18、bination of these.3.2.5 Time Base SectionThe time base section providesthe linear horizontal sweep, or baseline. It includes the hori-zontal deflection circuits and the clock and delay circuits thatcontrol repetition rate and positioning of signals on thebaseline.4. Significance and Use4.1 The recom
19、mended measurement procedures describedin this guide are intended to provide performance-relatedmeasurements that can be reproduced under the specified testconditions using commercially available test instrumentation.These measurements indicate capabilities of sections of theultrasonic examination i
20、nstrument independent of specifictransducers or examination conditions. Measurements aremade from normally available connectors or test points so thatno access to internal circuitry is required. Further, this guide isnot intended for service, calibration, or maintenance of cir-cuitry for which the m
21、anufacturers instructions are available.It is intended primarily for pulse echo flaw detection instru-ments operating in the nominal frequency range of 100 kHz to25 MHz, but the procedures are applicable to measurements oninstruments utilizing significantly higher frequency compo-nents.4.2 These pro
22、cedures can be applied to the evaluation of anypulse-echo ultrasonic examination instrument which can bedescribed as a combination of the electronic sections discussedin this guide.NOTE 2These procedures are not intended to preclude the use orapplication of equipment for which some or all of the mea
23、surementtechniques of this document are not applicable.4.3 An ultrasonic examination instrument that cannot becompletely described as a combination of the electronicsections discussed in this practice can be partially evaluated.Each portion of the ultrasonic examination instrument that isevaluated m
24、ust fit the description for the corresponding sec-tion.4.4 This guide is meant to be used by electronic personnel toevaluate the electronic system components and not the ultra-sonic system characteristics.5. Apparatus5.1 Ultrasonic InstrumentAny electronic instrument com-prised of a power supply, pu
25、lser, clock, receiver, and a sweepand display section to generate, receive, and display electricalsignals related to ultrasonic waves for examination purposes.NOTE 3Some ultrasonic instruments do not include a cathode ray tubedisplay. Some sections of this guide may not apply to these instruments,or
26、 may be applicable only with modifications. Such modifications shouldbe made only by personnel competent in electronics.5.2 VoltmeterAny instrument(s) capable of measuring theAC line and DC battery voltages required for 7.1 or 7.2.5.3 Variable TransformerAn autotransformer or otherdevice capable of
27、supplying variable AC power to the ultra-sonic instrument over the full range of voltages and waveformsspecified by the manufacturer.5.4 Pulser LoadUnless otherwise requested by the usingparties, the pulser load should be a 50-ohm noninductiveresistor, preferably mounted in a shielded coaxial assemb
28、ly.The resistor must be able to withstand the maximum peakpulser voltage. The impedance of the resistor should bechecked at the anticipated operating frequency to ensure that itis noninductive. Other impedances may be used if specified.5.5 Spectrum AnalyzerAny spectrum analyzer (and probeassembly if
29、 required) that is capable of analyzing the electricalpulse from the pulser module and displaying the frequencycomponents of the pulse as described in 8.3. A recording of thedisplay (photograph or chart recorder) is desirable.5.6 ProbeA wide band high input impedance ($10 kV)attenuating (1003 or 503
30、) probe to reduce the pulse ampli-tude, as delivered to the oscilloscope and the spectrum ana-lyzer, to a level that (a) will not harm the equipment and (b)will allow for frequency and time analysis without significantlyaltering the pulse shape. The probe output impedance shouldmatch the input imped
31、ance of the measurement instrument. (Ifthe impedance is high, a terminating resistance may berequired at the input to match the output impedance of theprobe.) The frequency bandwidth should be at least as wide asthat of the measuring instruments. The probe must be able towithstand the pulser output
32、voltage.NOTE 4More than one probe may be needed to match the various testinstruments used.5.7 Function GeneratorThe function generator should becapable of producing a single-cycle sine wave or a five-cyclesine wave burst (as required in 9.1.3, 9.2.3, 9.3.1, 10.1.1, and11.1), the frequency of which i
33、s variable over the range of thefrequency capabilities of the ultrasonic instrument. The fre-quency read-out should be accurate to 1.0 %. It must becapable of being triggered from a signal derived from theinstrument clock to provide wave trains coherent with thedisplay. An adjustable delay of at lea
34、st 10 s is required.E 1324 00 (2005)25.7.1 A free-running (that is, non-triggered) single-cyclesine wave may not be used for receiver evaluation.5.8 Calibrated OscilloscopeThe oscilloscope should becapable of displaying all portions of the pulser output withsufficient timebase expansion, triggering
35、capability, and fre-quency response to enable measurement of the pulse rise time,amplitude, and duration, as well as fulfilling the requirementsof other measurements.5.9 Calibrated AttenuatorThe attenuator should provide ameasuring range of 60 dB in 1 dB steps with an accuracywithin 60.5 dB and have
36、 a frequency bandwidth at least aswide as the highest frequency of interest. Most attenuatorshave a nominal input and output impedance of 50 V, but otherimpedances may be specified. Proper termination rules must beobserved. An impedance matching probe should be used toprotect the attenuator if it is
37、 to be used to reduce pulse output.5.10 TerminatorsTerminators are used to match the im-pedances of instruments and cables used (see 5.4.). Theyshould be non-inductive, feed-through style.5.11 CablesCables should be coaxial, with maximumlength of 6 ft 2 m and a 50-ohm characteristic impedance.Other
38、lengths, or impedances, or both, may be used if autho-rized, but lengths should be kept as short as possible tominimize the effects of cable capacitance on measurements.5.12 Search UnitAn ultrasonic search unit of the desiredtype, size, and frequency required for the procedures and testblock selecte
39、d for 5.14, 7.1.1, 7.2.1, 10.2,or10.3.5.13 Immersion Tank (Optional)An ultrasonic immersionsystem that will enable continuous variation of the distancebetween the ultrasonic search unit and a reflector over a waterpath range that will provide a time range comparable to the enduse of the ultrasonic i
40、nstrument. A distance (position) scale ofprecision needed for the procedure in 10.2 must be incorpo-rated.5.14 Test BlockAblock of any suitable material which canbe used to provide ultrasonic echo signals.5.15 Camera or RecorderThis is particularly helpful inmeasuring pulse characteristics, and is u
41、seful in making othermeasurements.6. Precautions and Limitations6.1 This guide describes procedures that are applicable tolaboratory measurement conditions using, in most instances,commercially available electronic test equipment.6.2 This guide is not intended, nor is it applicable, as aspecificatio
42、n defining the performance of ultrasonic examina-tion systems. If such performance criteria are required, theymust be agreed upon by the using parties.6.3 Implementation of this guide may require more detailedprocedural instructions. Competence in the use of the elec-tronic measurement instrumentati
43、on specified is a prerequisitefor effective use of these procedures.6.4 Careful selection of the specific measurements to bemade is recommended. If the related parameter is not relevantto the intended application, its measurement may be unneces-sary. For example, vertical linearity may be irrelevant
44、 for anapplication using a single-level flaw alarm, while horizontallinearity might be required only for accurate flaw-depth orthickness measurement from the instrument screen.6.5 No minimum interval between instrument evaluations isrecommended or implied.6.6 The accuracy of each measurement is depe
45、ndent uponthe combined accuracies of each of the electronic measuringinstruments (which should be described in the specificationsand calibrations for these instruments), and the precisionsassociated with reading the values of each part of the measure-ment system. It is assumed that the precision of
46、measuring thevertical and horizontal values from the ultrasonic instrumentscreen is 60.04 in. 61 mm.6.7 All measuring instrumentation should have current cali-bration certificates. A calibration control system, such as thatdescribed in MIL-STD-45662A, is suggested.7. Power-Supply Section Measurement
47、s7.1 AC-Powered Instrument Line Regulation:7.1.1 Connect the variable transformer, the voltmeter and asearch unit which matches the nominal frequency of theinstrument, to the ultrasonic instrument as shown in Fig. 1.While Fig. 1 shows an immersion set-up, the evaluation may beperformed by either the
48、 contact or immersion method. Theprimary requirement is that the signal from the referencereflector does not vary due to coupling or position variationsduring the evaluation. Contact tests may require clamping ofthe search unit to the test piece. A block with permanentlybonded search unit(s) is quit
49、e useful.7.1.2 Adjust the variable transformer for 100 % nominalline voltage and obtain a 50 % full-scale indication from thereference block. Decrease the variable transformer outputvoltage until the reference reflector indication changes itsamplitude, width, or horizontal position by 10 %.NOTE 5Damage may result from going beyond the manufacturersline voltage specifications in either direction.7.1.3 The ultrasonic instrument display may turn off beforeany significant signal change is noted.7.1.4 Record the variable transformer output voltage(s) atwhich
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