DIN EN 1971-2-2012 Copper and copper alloys - Eddy current test for measuring defects on seamless round copper and copper alloy tubes - Part 2 Test with an internal probe on the in.pdf

1、February 2012 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 23.040.15; 77.150.30!$yx“1868590www.din.deDDIN EN 1971-2Copper and copper alloys Eddy current test for measuring defects on seamless round copper andcopper alloy tubes Part 2: Test with an internal probe on the inner surfaceEnglish translation of DIN EN 1971-2:2012-02Kupfer und Kupferlegierungen W

3、irbelstromprfung an Rohren zur Messung von Fehlern an nahtlos gezogenen rundenRohren aus Kupfer und Kupferlegierungen Teil 2: Prfung mit Innensonde auf der InnenseiteEnglische bersetzung von DIN EN 1971-2:2012-02Cuivre et alliages de cuivre Mthode de contrle par courants de Foucault pour le mesurage

4、 des dfauts des tubesronds sans soudure en cuivre et alliages de cuivre Partie 2: Essai avec un capteur interne sur la paroi interneTraduction anglaise de DIN EN 1971-2:2012-02www.beuth.deDocument comprises pagesIn case of doubt, the German-language original shall be considered authoritative.1101.12

5、 DIN EN 1971-2:2012-02 2 A comma is used as the decimal marker. National foreword This standard has been prepared by Technical Committee CEN/TC 133 “Copper and copper alloys” (Secretariat: DIN, Germany). The responsible German body involved in its preparation was the Normenausschuss Nichteisenmetall

6、e (Nonferrous Metals Standards Committee), Working Committee NA 066-02-03 AA Kupferrohre (Installation und Industrie). EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 1971-2 December 2011 ICS 23.040.15; 77.150.30 English Version Copper and copper alloys - Eddy current test for measuring Cuivre

7、et alliages de cuivre - Mthode de contrle par courants de Foucault pour le mesurage des dfauts des tubes ronds sans soudure en cuivre et alliages de cuivre - Partie 2: Essai avec un capteur interne sur la paroi interneKupfer und Kupferlegierungen - Wirbelstromprfung an Rohren zur Messung von Fehlern

8、 an nahtlos gezogenen runden Rohren aus Kupfer und Kupferlegierungen - Teil 2: Prfung mit Innensonde auf der Innenseite This European Standard was approved by CEN on 5 November 2011. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving t

9、his European Standard the status of a national standard without 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

10、 versions (English, French, German). A version in any other 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 Aus

11、tria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUR

12、OPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 1971-2:2011: Edefects on se

13、amless round copper and copper alloy tubes - Part 2: Test with an internal probe on the inner surface EN 1971-2:2011 (E) 2 Contents Page Foreword 3Introduction .41 Scope 52 Normative references 53 Terms and definitions .54 General requirements 54.1 Personnel qualification .54.2 Condition of tube to

14、be tested 54.3 Equipment 65 Reference standard tube .66 Acceptance criteria 76.1 Detection of local discontinuities by internal probes systems 76.2 Detection of non-local discontinuities by internal probes systems with lower detection levels .76.3 Other test methods 87 Instrument adjustment 8Bibliog

15、raphy 9Figures Figure 1 Simplified representation of eddy current testing using internal probe .6 DIN EN 1971-2:2012-02 EN 1971-2:2011 (E) 3 Foreword This document (EN 1971-2:2011) has been prepared by Technical Committee CEN/TC 133 “Copper and copper alloys”, the secretariat of which is held by DIN

16、. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by June 2012, and conflicting national standards shall be withdrawn at the latest by June 2012. Attention is drawn to the possibility that some of th

17、e elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement t

18、his European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerla

19、nd and the United Kingdom. Within its programme of work, Technical Committee CEN/TC 133 requested CEN/TC 133/WG 3 “Copper tubes (installation and industrial)“ to prepare the following document: EN 1971-2, Copper and copper alloys Eddy current test for measuring defects on seamless round copper and c

20、opper alloy tubes Part 2: Test with an internal probe on the inner surface This is one of two parts of the standard for the eddy current test for measuring defects on seamless round copper and copper alloy tubes. The other part is: EN 1971-1, Copper and copper alloys Eddy current test for measuring

21、defects on seamless round copper and copper alloy tubes Part 1:Test with an encircling test coil on the outer surface DIN EN 1971-2:2012-02 EN 1971-2:2011 (E) 4 Introduction The eddy current test with internal probe described in this standard has the objective of detecting potential leaks and seriou

22、s defects in seamless round copper and copper alloy tubes. The eddy current test is able to detect material inhomogeneities and their positions throughout the length of tubes. The eddy current signals of material inhomogeneities are compared with reference signals of artificially produced test defec

23、ts. It is possible to identify these inhomogeneities on the inner and outer surfaces as well as within the tube wall. Since the distribution of eddy currents decreases as the distance from the test coil increases, the amplitude of defect signals also decreases with increasing distance from the test

24、coil. Thus the eddy current test with internal probe on the inner surface is less sensitive to defects on the outer surface. The purpose of this standard is not to define a method of measuring the actual extent of the material inhomogeneities as the signal amplitude is dependent on, amongst other fa

25、ctors, volume, form and position of the inhomogeneity. Due to end effects, it is not possible to effectively test the ends of the tubes. The purchaser and the supplier could agree that the end effect may be overcome by cutting to length after testing. DIN EN 1971-2:2012-02 EN 1971-2:2011 (E) 5 1 Sco

26、pe This European Standard specifies a procedure for the eddy current test with an internal probe for measuring defects on the inner surface of seamless round copper and copper alloy tubes. This European Standard applies particularly for finned tubes with high fins according to EN 12452. NOTE The edd

27、y current test method(s) required, together with the size range and acceptance level, are defined in the relevant product standard. The choice of the method for eddy current test: with an encircling test coil on the outer surface according EN 1971-1 or with an internal probe on the inner surface acc

28、ording EN 1971-2 is at the discretion of the manufacturer if there are no other agreements between the purchaser and the supplier. Especially for finned tubes according to EN 12452 with high fins, it is recommended to use eddy current test with internal probe as described in this standard. 2 Normati

29、ve references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 473, Non-destructive testing Qua

30、lification and certification of NDT personnel General principles EN ISO 12718, Non-destructive testing Eddy current testing Vocabulary (ISO 12718:2008) 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN ISO 12718 apply. 4 General requirements 4.1 Personn

31、el qualification The eddy current test shall be made by operators trained in this technique and it shall be done under the responsibility of qualified staff. When agreed upon between the purchaser and the supplier, qualification of the personnel shall be certified according to EN 473. 4.2 Condition

32、of tube to be tested Tubes shall be sufficiently clean and straight to permit satisfactory operation of optionally drive mechanism and eddy current test equipment. DIN EN 1971-2:2012-02 EN 1971-2:2011 (E) 6 4.3 Equipment The internal probe shall be moved through the tubes as vibration-free as possib

33、le. The variation in test sensitivity due to changes of speed and internal probe position within the tubes shall be maintained within 2 dB. The internal probe can be moved manually or by using a drive mechanism (see Figure 1). Key 1 tube with fins on the outside 2 internal probe Figure 1 Simplified

34、representation of eddy current testing using internal probe Test speed over the length of the tube shall be as constant as possible. The distance between the probe and the inner surface of the tube shall be kept as small as possible so that the sensitivity of the test is sufficient. NOTE For interna

35、l probes, the usual frequencies are in the range 1 kHz to 125 kHz. 5 Reference standard tube Unless otherwise specified in the relevant product standard, a reference standard tube is made of a defect-free tube of the same dimensions and specified properties as the tube to be tested. During the refer

36、ence test, the influence of dynamic conditions shall be taken into account. NOTE The producer can ensure that this requirement is met by the appropriate option subject to the type of the installation, such as: a) for control devices not in-line with production, the reference tube should be long enou

37、gh to ensure the same dynamic conditions for the reference test as for normal line operating speed; or b) the control devices should include a dynamic effect compensating unit to take into account the speed differences between the reference tube throughput speed and the normal line operating speed.

38、Either the reference standard tube shall have three holes located on three generating lines at 120, or only one hole. If a reference standard tube with three holes is used, the holes shall be spaced from each other and from each end, sufficiently to obtain separate signals from each hole without int

39、erference from the tube ends. If a reference standard tube with only one hole is used, then this tube shall be used three times being turned by 120. DIN EN 1971-2:2012-02 EN 1971-2:2011 (E) 7 The maximum drill diameter for the various dimension ranges is defined in the relevant product standards. Ot

40、her reference standard tube types may be considered if they are demonstrated as more relevant for certain products; they shall be defined in the relevant product standards. 6 Acceptance criteria 6.1 Detection of local discontinuities by internal probes systems Local discontinuities of the tubes, inc

41、luding beginning and end of long regular discontinuities and variations of long discontinuities, are detected as defects with internal probes systems. The sorting limit shall be the smallest amplitude of the three signals produced by the hole or holes in the reference standard tube. 6.2 Detection of

42、 non-local discontinuities by internal probes systems with lower detection levels Non-local discontinuities of the tube could be identified as defects by one of the methods defined for this purpose, according to the requirements of the relevant product standards. Some discontinuities of the tube, wh

43、ich individually are not considered as defective, might cause signals lower than the detection threshold of the normal sorting limit for local defects but higher than a second selected lower detection threshold Sl. The signals for the lower and normal detection thresholds are related by a ratio K2,

44、which shall be determined by the manufacturer of the tube, as follows: SS= Knl2(1) where Slis the signal for the lower detection threshold; Snis the signal for the normal detection threshold. A maximum density of defects d0shall be calculated as follows: LN= d000(2) where N0is the maximum permissibl

45、e number of discontinuities in a pre-set length; L0is the pre-set length. NOTE Both N0and L0should be determined by the tube manufacturer if they are not specified in the relevant product standard. Discontinuity signals ranging between the two sorting limits of the lower and normal detection thresho

46、lds along the pre-set length L0shall be counted as N. When the real density d = N/L0exceeds d0, the entire pre-set length affected shall be considered defective. DIN EN 1971-2:2012-02 EN 1971-2:2011 (E) 8 6.3 Other test methods For other test methods the acceptance criteria shall be defined specific

47、ally, such as for a system involving relative rotational motion between the tube and the surface probe. Equal or higher sensitivity shall be demonstrated. 7 Instrument adjustment The test system shall be adjusted, using a reference standard tube in accordance with Clause 5. If the test instrument op

48、erates with phase selection, the signals from the defects to be detected shall lie within the determined phase ranges. The sensitivity of the instrument shall be adjusted so that the smallest of the three signals exceeds the response threshold of the sorting limit. Adjustment of the instrument shall be carried out and checked for each change of product and at regular intervals of not more than 8 h during periods of continuous operation. If any check shows that a loss of sensitivity exc