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1、BRITISH STANDARD BS EN 13192:2002 Non-destructive testing Leak testing Calibration of reference leaks for gases The European Standard EN 13192:2001 has the status of a British Standard ICS 19.100 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Licensed Copy: sheffieldun sheffi
2、eldun, na, Sun Oct 29 09:44:41 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 13192:2002 This British Standard, having been prepared under the direction of the Engineering Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 29 J
3、anuary 2002 BSI 29 January 2002 ISBN 0 580 38965 0 National foreword This British Standard is the official English language version of EN 13192:2001. The UK participation in its preparation was entrusted to Technical Committee WEE/46, Non-destructive testing, which has the responsibility to: A list
4、of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International
5、 Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British
6、Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European develop
7、ments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 18, an inside back cover and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issue
8、d since publication Amd. No. DateComments Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:41 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 13192 November 2001 ICS 19.100 English version Non-destructive testing Leak testing Calibration of
9、 reference leaks for gases Essais non-destructifs Contrle dtanchit Etalonnage des fuites de rfrence des gaz Zerstrungsfreie Prfung Dichtheitsprfung Kalibrieren von Referenzlecks fr Gase This European Standard was approved by CEN on 10 October 2001. CEN members are bound to comply with the CEN/CENELE
10、C Internal Regulations which stipulate the conditions for giving this 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 Management Centre or to any CEN m
11、ember. This European Standard exists in three official 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 Management Centre has the same status as the official versions. CEN member
12、s are the national standards bodies of 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 STANDARDIZATION COMIT EUROPEN DE NORMALISATION
13、 EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels 2001 CENAll rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 13192:2001 E Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:41 GMT+00:00 2006,
14、 Uncontrolled Copy, (c) BSI EN 13192:2001 (E) 2 Contents Page Foreword. 3 1Scope . 4 2Normative references . 4 3Terms and definitions. 4 4Classification of leaks 5 4.1Permeation leak 5 4.2Conductance leaks 5 5Apparatus. 5 5.1Mass Spectrometer Leak Detector (MSLD), for methods A and B (see clause 6)
15、. 5 5.2Capillary measurement tube equipment for method C (see clause 7) 5 6Calibration by comparison (methods A and B) 6 6.1Preparation of leaks and apparatus 6 6.2Measurement 6 7Calibration by direct flow measurement (method C) 7 7.1Preparation of leaks and apparatus 7 7.2Measurement 8 8Results. 11
16、 8.1Evaluation for methods A and B (comparison) . 11 8.2Evaluation for method C (direct flow measurement). 15 9Report. 16 10Labelling of reference leaks. 16 11Handling of reference leaks. 16 11.1Permeation leaks (normally with reservoir fitted the leak outlet) 16 11.2Conductance leaks (normally with
17、out reservoir). 16 Annex A (informative) Calculation of leakage rate decrease due to tracer gas depletion in the reservoir. 17 Bibliography. 18 Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:41 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13192:2001 (E) 3 Foreword This European Standa
18、rd 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 or by endorsement, at the latest by May 2002, and conflictin
19、g national standards shall be withdrawn at the latest by May 2002. This European Standard has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association. This European Standard is considered to be a supporting standard to those application and produ
20、ct standards which in themselves support an essential safety requirement of a New Approach Directive and which make normative reference to this European Standard. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement
21、 this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:41 GMT+00:00 2006,
22、 Uncontrolled Copy, (c) BSI EN 13192:2001 (E) 4 1Scope This draft European Standard specifies the calibration of those leaks that are used for the adjustment of leak detectors for the determination of leakage rate in everyday use. The preferred calibration method in this case is a comparison with a
23、standard leak. In this way the leaks used for routine use become traceable to a primary standard as the ISO 9000 series of standards require. The comparison procedures are preferably applicable to helium leaks, because this test gas can be selectively measured by a mass spectrometer leak detector (M
24、SLD) (the definition of MLSD is given in EN 1330-8). Calibration by comparison (see methods A and B below) with known standard leaks is easily possible for leaks with reservoir and leakage rates below 10 -7Pam3/s. From 10-7 Pam3/s to 10-4 Pam3/s no leaks reliable enough to be used as transfer standa
25、rd exist. Leaks in this range can only be calibrated by measurement of flow in a calibrated capillary tube (see method C below). Leakage rates greater than 10-4 Pam3/s can be measured by flow meters calibrated against primary national standards. 2Normative references This European Standard incorpora
26、tes by dated or undated reference, provisions from other 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 Europea
27、n Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). EN 1330-8, Non-destructive testing Terminology Part 8: Terms used in leak tightness testing. EN 13625, Non-destructive testing Le
28、ak test Guide to the selection of instrumentation for the measurement of gas leakage. 3Terms and definitions For the purposes of this European Standard, the terms and definitions given in EN 1330-8 and the following apply. 3.1 unknown leak leak having a stable and repeatable leakage rate of known or
29、der of magnitude that can be determined by calibration 3.2 calibration of a reference leak set of operations which establish, under specified conditions, the relationship between leakage rate values represented by an unknown leak and the corresponding known values of the leakage rate by general defi
30、nition in: “International vocabulary of basic and general terms in metrology” NOTE 1In the case of calibration by comparison, the known values of the leakage rate are represented by a standard leak. NOTE 2Normally, the result of a calibration is given as the leakage rate value for the reference leak
31、. For proper usage of the different definitions of leakage rate, the following should be carefully considered: In leak detection, leakage rates are commonly given in units of pV-throughput (Pam3/s, mbar l/s). These are only a precise measure of gas flow if the temperature is given and kept constant.
32、 Flow units such as mass flow (g/y) or molar flow (mol/s) are sometimes used to overcome this problem. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:41 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13192:2001 (E) 5 4Classification of leaks 4.1Permeation leak This type of leak is norma
33、lly made with a tracer gas reservoir. It has the best long-term stability but an appreciable temperature coefficient (approximately 3,5 %/K). Typical leakage rates are in the range from 10- 10 Pam3/s to 10-4 Pam3/s. 4.2Conductance leaks 4.2.1Capillary leak This type of leak is available with or with
34、out a tracer gas reservoir. It has a low temperature coefficient (approximately 0,3 %/K) but easily blocks if not handled with care. Typical leakage rates are greater than 10-7 Pam3/s. 4.2.2Aperture leak (orifice) Orifice leaks are seldom used in practice, as they are difficult to manufacture and ev
35、en more prone to blocking than capillaries. 4.2.3Compressed powder leak This type of leak uses metal powder compressed into a tube. They are usually offered without reservoir. They are used for routine check of the sensitivity of leak detectors but they are not stable enough to be used as calibratio
36、n leaks. 5Apparatus 5.1Mass Spectrometer Leak Detector (MSLD), for methods A and B (see clause 6) To calibrate a leak by comparison to a known standard according to methods A and B described in clause 6, a mass spectrometer leak detector is necessary as the transfer device. Such a leak detector shal
37、l fulfil the minimum requirements for the measurement of leakage rate, laid down in EN 13625. The test port of the leak detector shall be equipped with an inlet system consisting of a set of ports with valves (preferably all metal) to couple the standard leak and the unknown leaks to the detection s
38、ystem and to shut off the leaks individually. The leak tightness of the inlet system shall be checked to a suitable level before a calibration is performed so that ambient tracer (e.g. helium of ambient atmospheric air) will not affect the measurement. 5.2Capillary measurement tube equipment for met
39、hod C (see clause 7) To calibrate a leak by measurement of capillary flow according to method C described in clause 7, a calibrated glass capillary tube (preferably with a suitable vent valve at one end, see Figure 1) is necessary. An indicator fluid (normally water with some surfactant added or spe
40、cial oils) is used to produce the measurement slug in the capillary. To measure the time of slug movement, a timer or stopwatch will be needed. Instruments based on the timed movements of a film in a tube are also available, e.g. a bubble flow meter. As conductance leaks normally have no tracer gas
41、reservoir, a separate tracer gas supply is needed or calibration may be performed with filtered atmospheric air. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:41 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13192:2001 (E) 6 6Calibration by comparison (methods A and B) There are two w
42、ays of calibrating leaks by comparison with known standard leaks. Both methods require the knowledge of the order of magnitude of the leakage rate to be measured. The methods differ in using one or two standard leaks, resulting in different uncertainties of measurement. In the following, the two met
43、hods are designated as A and B: Method A:Comparison to one standard leak normally with a leakage rate of the same order of magnitude Method B:Comparison to two standard leaks with leakage rates normally lying on either side of the unknown leakage rate Method A is most suitable for use on site as onl
44、y one standard leak is used. It is generally applicable but is most reliable when the leakage rate of the unknown is close to that of the standard leak. This is because the measurement uncertainty is directly dependent on the linearity of the leak detector in use. (See 8.1.2.2). As the linearity err
45、or cannot be measured independently, it has to be estimated. To keep the linearity error small, the operating characteristics of leak detector should not change during calibration (e.g. automatic ranging should be disabled). For more precise calibrations, where a definite measure of uncertainty is r
46、equired or if a standard leak with a leakage rate close to the unknown is not available method B should be used. By the use of two reference leaks, the non-linearity of the leak detector is accounted for (see 8.1.2.3). 6.1Preparation of leaks and apparatus 6.1.1Warm-up of leak detector The leak dete
47、ctor used as a transfer device shall be set up according to the manufacturers manual. The warm-up time shall be at least 2 h. 6.1.2Temperature accommodation The unknown leak and the standard leak(s) for the comparison shall be stored in the same room where the test is to be carried out for at least
48、12 h to allow for temperature equilibration (an air-conditioned room is not necessary if there are no rapid temperature changes. Because of temperature fluctuations, an air-conditioning system can even increase the measurement uncertainty). The leaks shall be pumped out during the phase of thermal a
49、ccommodation. After temperature accommodation, to prevent any temperature changes during measurement, thermally insulating hoods (made of plastic foam or similar material) should be put over the leaks. 6.1.3Connection to the leak detector The standard and unknown leaks are connected to the inlet system of the MSLD after temperature accommodation and pumped with their valves (if any) open for at least 30 min to remove any tracer gas that may have accumulated in seals or valves. For the calibration of more than one leak, a separa