1、November 2013 Translation by DIN-Sprachendienst.English price group 8No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).IC
2、S 19.100!%)“2069606www.din.deDDIN EN 13477-1Non destructive testing Acoustic emission Equipment characterisation Part 1: Equipment description;English version EN 13477-1:2001,English translation of DIN EN 13477-1:2013-11Zerstrungsfreie Prfung Schallemissionsprfung Charakterisierung der Prfausrstung
3、Teil 1: Gertebeschreibung;Englische Fassung EN 13477-1:2001,Englische bersetzung von DIN EN 13477-1:2013-11Essais non destructifs Emission acoustique Caractrisation de lquipement Partie 1: Description de lquipement;Version anglaise EN 13477-1:2001,Traduction anglaise de DIN EN 13477-1:2013-11Superse
4、desDIN EN 13477-1:2001-04www.beuth.deDocument comprises 10 pagesIn case of doubt, the German-language original shall be considered authoritative.10.13-DIN EN 13477-1:2013-11 2 A comma is used as the decimal marker. National foreword This document (EN 13477-1:2001) has been prepared by Technical Comm
5、ittee CEN/TC 138 “Non-destructive testing” (Secretariat: AFNOR, France). The responsible German body involved in its preparation was the Normenausschuss Materialprfung (Materials Testing Standards Committee), Working Committee NA 062-08-23 AA Ultraschallprfung. Amendments Compared with DIN EN 13477-
6、1:2001-04, the following corrections have been made: a) based on the correction of the German title of DIN EN 13477-2:2010-12, the title of DIN EN 13477-1:2001-04 has been corrected correspondingly; b) based on DIN EN 13477-2:2013-04, a number of corrections have been made to the German text. Previo
7、us editions DIN EN 13477-1: 2001-04 EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 13477-1January 2001ICS 19.100English versionNon-destructive testing - Acoustic emission - Equipmentcharacterisation - Part 1: Equipment descriptionEssais non destructifs - Emission acoustique -Caractrisation de lqu
8、ipement - Partie 1: Description delquipementZerstrungsfreie Prfung - Schallemissionsprfung -Charakterisierung der Prfausrstung - Teil 1: GertebeschreibungThis European Standard was approved by CEN on 28 December 2000.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which sti
9、pulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Management Centre or to any CEN member.This European Standard exist
10、s in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the officialversions.CEN members are the national standards bodies of
11、 Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement
12、Centre: rue de Stassart, 36 B-1050 Brussels 2001 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 13477-1:2001 EContents PageForeword. 31 Scope 42 Normative references 43 Terms and definitions. 44 Detection 44.1 Sensing element. 44.2
13、Sensor case . 54.3 Sensor characteristics 55 Signal conditioning. 55.1 Preamplifier 65.2 Cables 65.3 Post-amplification and frequency filtering. 66 Signal measurement . 66.1 Continuous signal. 66.2 Burst signal. 76.3 Waveform. 77 Analysis and output of results. 88 Automated system 88.1 Automated ana
14、lysis 88.2 Feedback to a control or alarm system 8DIN EN 13477-1:2013-11 EN 13477-1:2001 (E)2ForewordThis European Standard has been prepared by Technical Committee CEN/TC 138 “Non-destructive testing“, thesecretariat of which is held by AFNOR.This European Standard shall be given the status of a na
15、tional standard, either by publication of an identical text or byendorsement, at the latest by July 2001, and conflicting national standards shall be withdrawn at the latest by July2001.This European Standard has been prepared under a mandate given to CEN by the European Commission and theEuropean F
16、ree Trade Association . This European Standard is considered to be a supporting standard to thoseapplication and product standards which in themselves support an essential safety requirement of a New ApproachDirective and which make normative reference to this European Standard.This standard about “
17、Non destructive testing - Acoustic emission - Equipment characterisation” consists of thefollowing parts:Part 1: Equipment descriptionPart 2: Verification of operating characteristicsPart one of this standard gives a description of the main components of an AE monitoring system.Part two of this stan
18、dard gives methods and acceptance criteria for verifying the electronic performance of an AEmonitoring system. These methods and acceptance criteria are used to routinely check and verify the performance ofan AE monitoring system composed of one or more channels during its life time.According to the
19、 CEN/CENELEC Internal Regulations, the national standards organizations of the following countriesare bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France,Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Swed
20、en, Switzerlandand the United Kingdom.DIN EN 13477-1:2013-11EN 13477-1:2001 (E)31 ScopeThis European standard describes the main components that constitute an acoustic emission (AE) monitoring systemcomprising:- detection,- signal conditioning,- signal measurement,- analysis and output of results.2
21、Normative referencesThis European Standard incorporates by dated or undated reference, provisions from other publications. Thesenormatives references are cited at the appropriate places in the text and the publications are listed hereafter. Fordated references, subsequent amendments to or revisions
22、of any of these publications apply to this EuropeanStandard only when incorporated in it by amendment or revision. For undated references, the latest edition of thepublication referred to applies (including amendments).EN 1330-1, Non destructive testing - Terminology - Part 1: List of general termsE
23、N 1330-2, Non destructive testing - Terminology - Part 2: Terms common to the non destructive testing methodsEN 1330-9, Non destructive testing - Terminology - Part 9: Terms used in acoustic emission testing3 Terms and definitionsFor the purpose of this standard the definitions given in EN 1330-1, E
24、N 1330-2, EN 1330-9 and IEC 60050International Electrotechnical Vocabulary and the following apply:average signal level (ASL)rectified, time averaged AE signal.4 DetectionA piezoelectric sensor is the most commonly used device for detecting acoustic emission. It provides the mosteffective conversion
25、 of elastic waves (acoustic emission) into an electrical signal in the frequency range mostcommonly used for AE detection, 20 kHz - 1 MHz. In its simplest form it consists of a piezoelectric crystalline orceramic element, mounted in a protective case. The sensor detects a combination of wave types:
26、compressional,shear, surface (Rayleigh), plate (Lamb), arriving from any direction.4.1 Sensing elementThe sensing material affects the conversion efficiency, operating temperature range and cable drive capability. Leadzirconate titanate (PZT), a ceramic, is the most commonly used material. It can be
27、 manufactured in a wide range ofsizes and shapes.The size, shape and containment affect the sensitivity, directionality, frequency response and wave-mode response.Several elements may be combined to achieve a desired performance.DIN EN 13477-1:2013-11 EN 13477-1:2001 (E)44.2 Sensor caseThe sensor ca
28、se (usually metallic) determines the overall size and mechanical characteristics of the sensor. It mayhave an integral cable or a connector. The case provides a total electrical screening of the sensing element and isusually common to one pole of the sensing element. A faceplate of ceramic or epoxy
29、between the sensor element andtest object provides electrical isolation from the structure to avoid ground loop and induced electromagnetic noise.Depending on the method of assembly, the sensor can be made single ended or differential.In a single-ended device, the screen of a coaxial cable is connec
30、ted to the sensor case and to one side of the sensingelement.In a differential device, a screened twisted pair cable is used and the sensing element is usually split or machined sothat the screen does not conduct the electrical output signal. Differential sensors have normally improved immunity toel
31、ectromagnetic noise compared with single-ended sensors.The case may contain a low noise preamplifier. Incorporating the preamplifier inside the sensor case, eliminates thecable link between the sensor element and the preamplifier. This reduces signal loss and improves immunity toelectromagnetic nois
32、e. The drawbacks are that the sensor case becomes larger, the maximum temperature rating islimited by the electronics, and the preamplifier is not interchangeable, see also 5.1.4.3 Sensor characteristics4.3.1 Frequency responsePiezoelectric acoustic emission sensors are either resonant with a peak i
33、n a certain frequency range, i.e. thefrequency content of the transient signal is mostly determined by the resonant frequency of the sensing element, orbroad-band with a rather flat frequency response if properly damped. The response of a sensor is given in terms of itsoutput voltage versus frequenc
34、y for a standard mechanical stimulus. Due to the inertia of piezoelectric sensors theirresponse will be different to continuous and transient stimuli. Most piezoelectric devices will be characterised bysurface velocity (volts per metre per second) as a function of frequency for a transient input. An
35、 exception is the “flatresponse“ device which is often characterised in terms of surface displacement (volts per unit displacement).Continuous signal response may be characterised in the same way or in pressure terms (volts per microbar).4.3.2 DirectionalityThe directionality is a measure of the uni
36、formity of the device response to signals coming from any direction along thesurface of the object to which the device is attached. It is usually called the polar response and quoted as a deviationabout the mean in dB. Sensors may be intentionally directional to preferentially monitor a specific are
37、a.4.3.3 Wave mode responseSensors may be made responsive to a particular wave mode, such as: shear, compressional or other waves.4.3.4 Operating temperatureThis depends on the construction materials and the characteristics of the sensor element. It shall be used within thetemperature range specified
38、 by the manufacturers.5 Signal conditioningIncluded in this section is preamplification, cables and post amplification.DIN EN 13477-1:2013-11EN 13477-1:2001 (E)55.1 PreamplifierThe main preamplifier characteristics are the input impedance, noise, gain, bandwidth, filter characteristics such asroll-o
39、ff rate, output impedance, operating temperature range, common-mode rejection ratio (CMRR) and dynamicrange.Preamplification can be of voltage or charge. Voltage preamplification converts the sensor output, usually a highimpedance low-level signal, to a low impedance high-level signal for the transm
40、ission over long signal lines to themeasurement instrumentation, which may be up to several hundred metres away.A typical preamplifier has a high input impedance, 40 dB gain and 50 output impedance to drive a coaxial cable.The D.C. power supply to the preamplifier is commonly supplied on the same ca
41、ble as the signal output anddecoupled at each end using a filter network.The preamplifier input may be single-ended, differential or switchable to fit different sensor types. For some industrialapplications, preamplifiers are an integral part of the AE sensor, providing greater ruggedness, reliabili
42、ty, reducedsignal loss due to cable impedance and reduced susceptibility to electromagnetic noise.The design of the preamplifier may allow the sensor to be used as a pulser transducer for calibration purposes.Charge preamplification eliminates the effect of cable capacitance on the signal but is not
43、 widely used.5.2 Cables5.2.1 Sensor to preamplifier cableThis is the most important cable in the system and should be of low-capacitance, ( 100 pF/m), fully screened, andkept as short as possible ( 1 m) where voltage preamplification is used.5.2.2 Preamplifier to instrument cableThis is normally a s
44、creened coaxial 50 impedance cable matched to the preamplifier and measurement instrument.Care shall be taken to avoid crosstalk problems with multi-conductor cables, particularly if individual conductors areused to transmit a wide band pulser signal for periodic calibration during a test.5.2.3 Scre
45、enA single-point ground for all the screens is normally used at the measurement instrumentation. The screens of thecables shall not form ground loops.5.3 Post-amplification and frequency filteringPost-amplification and further analogue filtering is used at the measurement instrumentation to increase
46、 the signallevel and remove unwanted low or high frequency signals for measurement purposes. The input impedance, dynamicrange, filter characteristics, gain or attenuation are relevant to this section. The input stage usually provides D.C.power for the preamplifier and, sometimes, may control pulser
47、 operation.6 Signal measurement6.1 Continuous signalA continuous signal is characterised by the measurement of RMS (Root Mean Square) or ASL (Average Signal Level)with a particular time constant. Continuous signal measurement systems are used where there is no requirement toidentify and characterise
48、 individual emissions (bursts), e.g., process monitoring and leak detection. The measuredcharacteristics and their dynamic range define this type of system.DIN EN 13477-1:2013-11 EN 13477-1:2001 (E)66.2 Burst signalBurst signal measurement systems identify and characterise individual acoustic emissi
49、ons on the basis of their timeabove an amplitude threshold.The parameters of each burst signal may comprise any or all of the following, depending on the type of system and itsuser set-up:- peak amplitude;- time to peak amplitude;- arrival time;- rise-time,- duration;- ringdown count;- count to peak amplitude;- energy;- average frequency;- RMS level;- ASL;- detection threshold level;- others.External slow-varying parameter data, such as pressure, temperature, load or strain may also be acquired as part
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