NF-EN-13185-2001-ENG.pdf

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1、NF EN 13185 novembre 2001 Ce document est usage exclusif et non collectif des clients Saga Web. Toute mise en rseau, reproduction et rediffusion, sous quelque forme que ce soit, mme partielle, sont strictement interdites. This document is intended for the exclusive and non collective use of Saga Web

2、 customers. All network exploitation, reproduction and re-dissemination,even partial, whatever the form (hardcopy or other media), is strictly prohibited. Saga Web Pour THALES CORPORATE SERVICES SAS - EPM Client 04988312 le 19/6/2009 10:49 AFNOR 2001AFNOR 20011st issue 2001-11-P AFNOR 2001 All right

3、s reserved FE047853ISSN 0335-3931 NF EN 13185 November 2001 Classification index: A 09-492 European standard French standard Published and distributed by Association Franaise de Normalisation (AFNOR French standard institute) 11, avenue Francis de Pressens 93571 Saint-Denis La Plaine Cedex Tel.: + 3

4、3 (0)1 41 62 80 00 Fax: + 33 (0)1 49 17 90 00 www.afnor.fr ICS: 19.100 Non-destructive testing Leak testing Tracer gas method F : Essais non destructifs Contrle dtanchit Mthode par gaz traceur D : Zerstrungsfreie Prfung Dichtheitsprfung Prfgasverfahren French standard approved by decision of the Dir

5、ector General of AFNOR on October 5, 2001 taking effect on November 5, 2001. Replaces the approved standard NF A 09-492 dated August 1989. CorrespondenceThe European standard EN 13185:2001 has the status of French standard. AnalysisThis document specifies the methods to apply in order to detect a le

6、ak by means of a tracer gas and a leak detector specifically linked to the tracer gas which is used. The detection principles, the creation as well as the detection of the tracer gas are also explained. DescriptorsTechnical International Thesaurus: nondestructive tests, gas permeability tests, inspe

7、ction, leak detection, gases, procedure, vacuum technology, chemical tests, ammonia(gas). ModificationsWith respect to document replaced, adoption of the European standard. Corrections NF EN 13185:2001 2 National foreword References to French standards The correspondence between the standards figuri

8、ng in the clause “Normative references“ and the identical French standards is as follows:1) EN 473: NF EN 473 (classification index: A 09-010) EN 1330-8: NF EN 1330-8 (classification index: A 09-020-8) EN 1779: NF EN 1779 (classification index: A 09-105) EN 13192: NF EN 13192 (classification index:

9、A 09-461) 1) EN 13625: NF EN 13625 (classification index: A 09-462) 1) 1)Currently being prepared. EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 13185 March 2001 ICS 19.100 English version Non-destructive testing - Leak testing - Tracer gas method Essais non destructifs - Contrle dtanchit - M

10、thode par gaz traceur Zerstrungsfreie Prfung - Dichtheitsprfung - Prfgasverfahren This European Standard was approved by CEN on 18 January 2001. 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

11、national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in

12、any other language made by translation under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germa

13、ny, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels 2001 CENAll right

14、s of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 13185:2001 E Page 2 EN 13185:2001 Contents Page Foreword3 1Scope 4 2Normative references 4 3Terms and definitions4 4Personnel qualification .4 5Principles of detection 4 6Generation and detection

15、of tracer gas flow.5 6.1Tracer gas flows into the object ( Group A techniques ).5 6.2Tracer gas flows out of the object (Group B techniques): 5 7Apparatus - see prEN 13625:20015 8Object preparation.5 9Group A techniques, tracer gas flowing into the object6 9.1Initial system set up procedure6 9.2Vacu

16、um technique (total) test procedure (A.1)7 9.3Vacuum technique (partial) test procedure ( A2 ).8 9.4Vacuum technique (local) test procedure (A.3)8 10Group B techniques, tracer gas flowing out of object.8 10.1Initial system set up procedure9 10.2Ammonia test procedure (B.1).10 10.3Vacuum box test pro

17、cedure (B.2.1, B.2.2).11 10.4Accumulation technique procedures (B.3, B.6)12 10.5Sniffing test (B.4) .14 10.6Pressure evacuation procedure ( B.5).14 11Test report 16 Annex A (informative) Accumulation technique : calibration leak connected to enclosure of unknown volume.17 Annex ZA (informative) Clau

18、ses of this European Standard addressing essential requirements or other provisions of EU Directives18 Page 3 EN 13185:2001 Foreword This European Standard has been prepared by Technical Committee CEN/TC 138 “Non-destructive testing“, the secretariat of which is held by AFNOR. This European Standard

19、 shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by September 2001, and conflicting national standards shall be withdrawn at the latest by September 2001. This European Standard has been prepared under a mandate given to C

20、EN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s). For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this standard. Annex A is informative. According to the CEN/CENELEC Internal Re

21、gulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and th

22、e United Kingdom. Page 4 EN 13185:2001 1 Scope This standard describes the techniques to be applied for the detection of a leak, using a tracer gas and a tracer gas specific leak detector. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other

23、 publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or r

24、evision. For undated references the latest edition of the publication referred to applies (including amendments). EN 473 Qualification and certification of NDT personnel - General principles EN 1330 - 8 Non destructive testing Terminology -Part 8 : Terms used in leak tightness testing EN 1779 Non de

25、structive testing -Leak Testing Criteria for method and technique selection prEN 13192:2001 Non destructive testing -Leak test Calibration of gaseous reference leaks prEN 13625:2001 Non destructive testing -Leak test - Guide to the selection of instrumentation for the measurement of gas leakage. 3 T

26、erms and definitions For the purposes of this European Standard, the terms and definitions given in EN 1330-8 apply. 4 Personnel qualification It is assumed that leak testing is performed by qualified and capable personnel. In order to provide this qualification, it is recommended to certify the per

27、sonnel in accordance with EN 473 or equivalent. NOTEFor pressure equipment see directive 97/23/EC (Annex I, paragraph 3.1.3) : “For pressure equipment in categories III and IV, the personnel must be approved by a third party organization recognized by a Member State“ 5 Principles of detection A part

28、ial pressure difference of tracer gas is created across the boundary of the object to be tested. The tracer gas, having passed through the leak, is revealed by its physical or chemical properties. Chemical detection is generally based on reactions that cause a local colour change (the object surface

29、 shall therefore be visible). Detection based on physical properties usually involves a sensor, for example: ? a mass spectrometer, tuned for the specific tracer gas used (generally helium-4 ); ? an alkali ion diode, for halogen gas, and electron-capture equipment (i.e. for SF6 ); ? a Pirani gauge,

30、for tracer gas with thermal conductivity different from that of the ambient atmosphere; ? a photometer, with band-pass filter in the frequency range of the tracer gas absorption or emission. These types of detection generally give an electrical signal which varies with the tracer gas partial pressur

31、e. Page 5 EN 13185:2001 6 Generation and detection of tracer gas flow Two basic techniques are used - see EN 1779 6.1 Tracer gas flows into the object ( Group A techniques ) A pressure difference across the wall is obtained either by evacuation of the object, e.g. through a connection or by placing

32、it in a pressurized chamber. Usually the test object is evacuated. Tracer gas is then applied to the external surface using a probe jet or by enclosing the object (totally or partially ) in a hood or chamber filled with the tracer gas. Tracer gas leakage into the test object is detected by a sensor

33、within or connected to the internal volume. 6.2 Tracer gas flows out of the object (Group B techniques): The object is filled with a tracer gas. A pressure difference across the wall is obtained either by pressurization of the object, e.g. through a connection or by placing it in a vacuum chamber. T

34、he tracer gas is collected on the outside surface by a sampling probe or by accumulation into a hood or chamber. Tracer gas can also be detected by chemical reactions. A special technique (bombing ) may also be used. This involves pressurization of a sealed object to force tracer gas into its intern

35、al cavities, if a leak exists. The object is then placed in a vacuum chamber and escaping tracer gas is detected (usually this procedure is used only with helium- 4). This method is applicable to specimens with small free internal volumes (in the order of a few cubic centimetres). 7 Apparatus - see

36、prEN 13625:2001 The test apparatus can include part or all of the following: 7.1Leak detector or chemical reagents able to detect the selected tracer gas 7.2Calibration leaks, calibrated for discharge into vacuum and/or against atmospheric pressure ; refer to prEN 13192:2001. 7.3Pressure and tempera

37、ture gauges 7.4Tracer gas or certified gas mixture. 7.5Auxiliary vacuum systems 7.6Hood, vacuum or pressurizing chamber, jet or sampling probe 7.7Purging dry gas, liquid nitrogen (for cold trap), if necessary. 7.8Equipment for tracer gas treatment-recovery 7.9Equipment for test area ventilation 7.10

38、Data recording equipment 8 Object preparation The object to be tested shall be adequately cleaned, degreased and dried. Openings and apertures which are not involved in the test must be closed with test seals, e.g. plugs, welding, suitable material and gaskets. Whenever possible, testing should be c

39、arried before plating, painting or the application of ultrasonic couplant. Page 6 EN 13185:2001 If the object has to be evacuated, the presence of porous or plastic materials should be avoided. This helps to avoid spurious indications (virtual leaks), and shortens the clean up time. The connections

40、between the object, the pumping system, the leak detector or (LD) and the calibration leaks used shall be suitable and checked for tightness. 9 Group A techniques, tracer gas flowing into the object. These techniques are applicable to an object that can be evacuated or withstand an external test pre

41、ssure. The tracer gas is applied on the outer surface of the object and the LD is connected to the internal volume. If the LD is of Mass Spectrometer type (MLSD), the pumping system of the MSLD itself can be used to evacuate directly small items under test. Larger objects need an auxiliary pumping s

42、ystem. In this case, the loss of sensitivity shall be considered, as only part of the tracer gas will enter the LD. Three techniques may be used - refer to EN 1779: - Vacuum technique (Total) A.1 The object, placed in an enclosure (a bag or a chamber), is evacuated and connected to the detector. The

43、 enclosure is then filled with the tracer gas or a gas mixture containing the tracer gas. This technique allows the evaluation of the leakage rate but does not permit precise location of the leaks. When the purpose of the leak testing is the determination of the acceptability of the test object agai

44、nst a specified leakage rate, only the integral technique shall be used. In this case, the tracer gas concentration, pressure and temperature shall be measured and the homogeneity of the gas mixture shall be ensured. Further the enclosure shall be gas-tight and, preferably, rigid. - Vacuum technique

45、 (Partial) A.2 The object to be tested is evacuated and connected to the detector. Suspect areas are then covered by a suitable gas-tight enclosure filled with tracer gas. - Vacuum technique (Local) A.3 The object to be tested is evacuated and connected to the detector. Suspect areas on the external

46、 surface of the object are sprayed with tracer gas. Leaks can be localised using this technique but it is not possible to measure the total leakage rate. 9.1 Initial system set up procedure 9.1.1The LD shall be adjusted in accordance with manufacturers instructions, using a calibration leak (if requ

47、ired the leak shall be “standard“). If a MSLD is used, a leak for discharge to vacuum has to be connected directly to the inlet of the LD, or the built-in leak for the calibration is to be used. 9.1.2The object is connected to the LD and then evacuated to a suitable pressure, either by LD pumping sy

48、stem or by an auxiliary pumping system. This is determined by the maximum inlet pressure of the LD. 9.1.3The initial background signal shall be measured. 9.1.4The maximum signal for the specified calibration leak connected to the object shall be recorded to verify the system sensitivity. The ratio o

49、f the pumping speed of the LD to the pumping speed of the auxiliary system shall not be altered. 9.1.5For large objects or complex systems, the “response time“ of the system shall be measured by means of a suitable calibration leak the rate of leakage of which is as near as possible to the specified maximum allowable leakage. Unless otherwise specified, this leak shall be connected to the object under test, via an isolation valve, in the most unfavourable position, to determine the response time. An auxiliary line sho