1、BSI Standards PublicationBS EN 12668-3:2013Non-destructive testing Characterization andverification of ultrasonicexamination equipmentPart 3: Combined equipmentBS EN 12668-3:2013 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 12668-3:2013.It supersedes BS EN 12
2、668-3:2000 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee WEE/46, Non-destructive testing.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessarypro
3、visions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2013. Published by BSI StandardsLimited 2013ISBN 978 0 580 81771 7ICS 19.100Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published u
4、nder the authority of theStandards Policy and Strategy Committee on 30 November 2013.Amendments issued since publicationDate Text affectedBS EN 12668-3:2013EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 12668-3 November 2013 ICS 19.100 Supersedes EN 12668-3:2000English Version Non-destructive
5、testing - Characterization and verification of ultrasonic examination equipment - Part 3: Combined equipmentEssais non destructifs - Caractrisation et vrification de lappareillage de contrle par ultrasons - Partie 3: Equipement complet Zerstrungsfreie Prfung - Charakterisierung und Verfizierung der
6、Ultraschall-Prfausrstung - Teil 3: Komplette Prfausrstung This European Standard was approved by CEN on 29 September 2013. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard with
7、out any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other
8、language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, De
9、nmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITT
10、EE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2013 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12668-3:2013: EBS EN 12668-3
11、:2013EN 12668-3:2013 (E) 2 Contents Page Foreword 3 1 Scope 4 2 Normative references 4 3 Description of tests and reporting .4 3.1 General 4 3.2 Ultrasonic instrument checks 5 3.2.1 Linearity of the timebase 5 3.2.2 Linearity of equipment gain 6 3.3 Probe checks 7 3.3.1 Probe index point.7 3.3.2 Bea
12、m angle .7 3.3.3 Index point and beam angle simultaneously 8 3.4 System checks: Probe, cable and ultrasonic instrument combined 8 3.4.1 Measurement of base values 8 3.4.2 Physical state and external aspects 9 3.4.3 Sensitivity and signal-to-noise ratio 9 3.4.4 Pulse duration . 10 BS EN 12668-3:2013E
13、N 12668-3:2013 (E) 3 Foreword This document (EN 12668-3:2013) has been prepared by Technical Committee CEN/TC 138 “Non-destructive testing”, the secretariat of which is held by AFNOR. This European Standard shall be given the status of a national standard, either by publication of an identical text
14、or by endorsement, at the latest by May 2014, and conflicting national standards shall be withdrawn at the latest by May 2014. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for id
15、entifying any or all such patent rights. This document supersedes EN 12668-3:2000. This European Standard is composed of the following parts: EN 12668-1, Non-destructive testing Characterization and verification of ultrasonic examination equipment Part 1: Instruments; EN 12668-2, Non-destructive tes
16、ting Characterization and verification of ultrasonic examination equipment Part 2: Probes; EN 12668-3, Non-destructive testing Characterization and verification of ultrasonic examination equipment Part 3: Combined equipment (this document). According to the CEN-CENELEC Internal Regulations, the nati
17、onal standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lit
18、huania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 12668-3:2013EN 12668-3:2013 (E) 4 1 Scope This European Standard describes methods and acceptance criteria for verifying the performance of
19、ultrasonic equipment (i.e. instrument and probe combined as defined in EN 12668-1 and EN 12668-2) by the use of appropriate standard calibration blocks. These methods are not intended to prove the suitability of the equipment for particular applications. The methods described are suitable for the us
20、e by operators working under site or shop floor conditions. The methods only apply to pulse echo equipment using A-scan presentation, with gain controls or attenuators calibrated in steps not greater than 2 dB and used essentially in contact testing. These methods are specifically intended for manua
21、l testing equipment. For automated testing different tests can be needed to ensure satisfactory performance. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edit
22、ion cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 12668-1, Non-destructive testing - Characterization and verification of ultrasonic examination equipment - Part 1: Instruments EN 12668-2, Non-destructive testing - Charact
23、erization and verification of ultrasonic examination equipment - Part 2: Probes EN ISO 2400, Non-destructive testing - Ultrasonic testing - Specification for calibration block No. 1 (ISO 2400) EN ISO 7963, Non-destructive testing - Ultrasonic testing - Specification for calibration block No. 2 (ISO
24、7963) 3 Description of tests and reporting 3.1 General The methods described in this European Standard, together with the frequency of checking, are summarized in Table 1. Compliance with the checks shall be recorded on the ultrasonic test report. BS EN 12668-3:2013EN 12668-3:2013 (E) 5 Table 1 Test
25、s for combined equipment Subclause Title Frequency of checking 3.2.1 Linearity of timebase Weekly a3.2.2 Linearity of equipment gain Weekly a3.3.1 Probe index Daily 3.3.2 Beam angle Daily 3.4.2 Physical state and external aspects Daily 3.4.3 Sensitivity and signal-to-noise ratio Weekly a3.4.4 Pulse
26、duration Weekly aaTo simplify the recording of weekly checks it may be more convenient for the user to perform them each time the equipment is used. 3.2 Ultrasonic instrument checks 3.2.1 Linearity of the timebase 3.2.1.1 General This check is carried out using a standard calibration block defined i
27、n EN ISO 2400 or EN ISO 7963, and a normal-beam compression wave probe or shear wave angle-beam probe. The linearity shall be checked over a range at least equal to that which is to be used in subsequent testing. Where appropriate, due allowance can be made for the fact that a range of 91 mm for com
28、pressional waves in steel is equivalent to a range of only 50 mm for shear waves. 3.2.1.2 Procedure Place the probe on the calibration block in a position where the range to the last backwall or radius echo is equal to or exceeds the range over which the linearity shall be checked. Adjust the timeba
29、se so that the first and the sixth backwall echoes coincide with the first and last scale marks respectively. Check the linearity with the four other echoes. Bring the backwall echoes, in turn, to approximately the same height e.g. 80 % full screen height. The leading edge of each echo should line u
30、p with the appropriate graticule line. Check that any deviations from the ideal positions are within the specified tolerance when measured at the same screen height when the first and the sixth echo were positioned. 3.2.1.3 Tolerance The deviation from linearity shall not exceed 2 % of full screen w
31、idth. 3.2.1.4 Frequency of checking The check shall be carried out at least once per week for ultrasonic instruments to be used during that week. BS EN 12668-3:2013EN 12668-3:2013 (E) 6 3.2.2 Linearity of equipment gain 3.2.2.1 General This check monitors the combined result of two characteristics t
32、hat affect the linearity of the equipment gain, i.e. the linearity of amplifier and the accuracy of the calibrated gain control. Any standard calibration block can be used for this test, preferably in conjunction with the probe that will be used in subsequent testing. The linearity shall be checked
33、with the ultrasonic instrument controls (frequency, range, pulse energy, etc.) switched to positions to be employed in subsequent testing. Variable suppression and swept gain controls shall be switched to “off”. 3.2.2.2 Procedure Position the probe on a calibration block to obtain a reflected signal
34、 from a small reflector e.g. the 5 mm hole in the EN ISO 7963 block. Adjust the gain to set this signal to 80 % of full screen height and note the value of the calibrated gain control (dB). Then increase the gain by 2 dB and confirm that the signal rises to more than full screen height (101 %). Rest
35、ore the gain to its original value and then reduce it by a further 6 dB. Confirm that the signal amplitude falls to approximately 40 % screen height. Successively reduce the signal by three further increments of 6 dB and confirm that the signal amplitude falls respectively to 20 %, 10 % and 5 % scre
36、en height. 3.2.2.3 Tolerance To be acceptable, signal amplitude shall be within the limits given in the following Table 2. Table 2 Acceptance limits for gain linearity Gain dB Expected screen height (%) Limits +2 101 not less than 95 % 0 80 (reference line) 6 40 37 % to 43 % 12 20 17 % to 23 % 18 10
37、 8 % to 12 % 24 5 visible, below 8 % 3.2.2.4 Logarithmic amplifiers If the ultrasonic instrument is using a logarithmic amplifier, subclauses 3.2.2.1 to 3.2.2.3 shall be replaced by an overall input/output amplitude accuracy test of the instrument according to manufacturers specification. The test s
38、hall verify that errors do not exceed 1 dB in any 20 dB span and 2 dB in any 60 dB span. 3.2.2.5 Frequency of checking The check shall be carried at least once per week for ultrasonic instruments to be used during that week. BS EN 12668-3:2013EN 12668-3:2013 (E) 7 3.3 Probe checks 3.3.1 Probe index
39、point 3.3.1.1 General This check applies only to angle beam probes. The probe index point can be checked on the standard EN ISO 2400 or EN ISO 7963 calibration block each of which has a cylindrical reflector (quadrant). The probe index point shall be checked prior to checking the beam angle. 3.3.1.2
40、 Procedure Position the probe on the appropriate side of the block to obtain a reflection from the quadrant. Move the probe backwards and forwards to maximize the amplitude of the reflected signal, taking care to move the probe parallel to the block sides. When the amplitude is at maximum, the true
41、probe index point will correspond to the engraved line on the block which marks the geometrical centre of the quadrant. The probe index point measurement should be repeatable to within 1 mm. If the measured position differs from the existing mark by more than 1 mm the new position shall be marked on
42、 the probe sides, and recorded, and shall be used in subsequent probe checks and defect plotting. 3.3.1.3 Tolerance Tolerance will depend on application, but for plotting of defects it is recommended that the probe index point position is known to within 1 mm. 3.3.1.4 Frequency of checking This will
43、 depend on the rate of probe wear due to usage and to the roughness of the scanning surface. When a probe is in continuous use, the check shall be carried out at least every few hours; otherwise, a daily check shall be performed for probes to be used during that day. 3.3.2 Beam angle 3.3.2.1 General
44、 The reference blocks defined in EN ISO 2400 or EN ISO 7963 provide a means of rapidly checking the beam angle. If a higher accuracy is needed, the angle shall be determined using one of the methods described in EN 12668-2. 3.3.2.2 Procedure Place the probe on the calibration block and establish a s
45、ignal from the selected hole. Move the probe backwards and forwards to maximize the signal from the hole. When the signal is at its maximum amplitude, the beam angle can be read from the engraved scale on the calibration block at a point directly below the measured probe index point. The deviation b
46、etween measured and nominal angle shall be recorded. 3.3.2.3 Tolerance Using the method previously described it is possible to measure the beam angle to an accuracy of approximately 1,5. Unless the probe history is known, previously marked probe angles should not be regarded as accurate, especially
47、on 70 or higher angle beam probes, or on worn probes. It is recommended BS EN 12668-3:2013EN 12668-3:2013 (E) 8 that the newly measured angle be marked on the probe and recorded for future reference during the subsequent probe checks and/or defect plotting applications. Tolerances will depend on the
48、 application but for some procedures it is recommended that the angle is within 2. 3.3.2.4 Frequency of checking Frequency of checking will depend on the rate of probe wear due to usage and the roughness of the scanning surface. When a probe is in continuous use, the check shall be carried out at le
49、ast every few hours; otherwise, a daily check shall be performed for probes to be used during that day. 3.3.3 Index point and beam angle simultaneously This method requires the use of a reference block containing at least 3 and preferably 4 or more side-drilled holes at different depths. The direct echo from each hole is maximized in turn and the reduced projection distance (a) from the centre of the hole to the front face of the probe is measured in each case. By plotting these distances against the depth position of the holes
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