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1、BRITISH STANDARD BS EN 13625:2002 Non-destructive testing Leak test Guide to the selection of instrumentation for the measurement of gas leakage The European Standard EN 13625:2001 has the status of a British Standard ICS 19.100 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW
2、Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 13625:2002 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 Poli
3、cy and Strategy Committee on 05 March 2002 BSI 05 March 2002 ISBN 0 580 39203 1 National foreword This British Standard is the official English language version of EN 13625:2001. The UK participation in its preparation was entrusted to Technical Committee WEE/46, Non-destructive testing, which has t
4、he responsibility to: A list 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 se
5、ction entitled “International 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 applicatio
6、n. Compliance with a British 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 inter
7、national and European developments 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 19 and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendment
8、s issued since publication Amd. No. DateComments Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 13625 December 2001 ICS 19.100 English version Non-destructive testing - Leak test - Guide
9、to the selection of instrumentation for the measurement of gas leakage Essais non destructifs - Contrle dtanchit - Guide pour la slection des instruments utiliss pour le mesurage des fuites gazeuses Zerstrungsfreie Prfung - Dichtheitsprfung - Anleitung zur Auswahl von Gerten zur Messung von Gaslecka
10、gen This European Standard was approved by CEN on 5 October 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 national standard without any alteration. Up-to-date lists and bibliographical
11、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 any other language made by translation under the responsibility of a CEN member
12、 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, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal,
13、 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 rights of exploitation in any form and by any means reserved worldwide for CEN natio
14、nal Members. Ref. No. EN 13625:2001 E Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13625:2001 (E) 2 Contents page Foreword3 1Scope 4 2Normative references 4 3Terms and definitions4 4Tracer gas method - Group A techniques (gas flowing i
15、nto object) 4 4.1Equipment and Material required for all group A techniques.4 4.2Vacuum technique.5 5Tracer gas method - Group B techniques (gas flowing out of the object) 6 5.1Equipment and materials required for all group B techniques.6 5.2Ammonia technique (B.1)7 5.3Vacuum box technique, for larg
16、e enclosures or open walls (B.2.1, B.2.2)7 5.4Enclosure techniques (B.3, B.6).8 5.5Direct sample probing technique (B.4)8 5.6Pressurizing-Evacuation technique (B.5)8 5.7Sealed object by vacuum technique (B.6).9 6Bubble test method - Group C techniques9 6.1Immersion technique (C.1)9 6.2Liquid applica
17、tion technique (C.2).10 6.3Liquid technique with vacuum box10 7Total pressure change method - Group D techniques.11 7.1Equipment and Material required for all group D techniques.11 7.2Pressure decay technique (D.1) .11 7.3Pressure rise technique (D.2).12 7.4Pressure change test (bell pressure change
18、 D.3) .12 7.5Flow measurement technique (D.4) .13 Bibliography19 Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13625:2001 (E) 3 Foreword This European Standard has been prepared by Technical Committee CEN/TC 138 “Non-destructive testing
19、“, 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 June 2002, and conflicting national standards shall be withdrawn at the latest by June 2002. According
20、 to the CEN/CENELEC Internal Regulations, 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, Sp
21、ain, Sweden, Switzerland and the United Kingdom. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13625:2001 (E) 4 1 Scope This European Standard specifies criteria for the selection of equipment for the leak detection methods described in
22、 EN 1779. The minimum requirements for the performance of the instruments used are also given as a guideline for personnel involved in testing. The definite selection of an instrument for a given test is within the responsibility of a qualified operator (at minimum level 2 qualification see EN 473).
23、 2 Normative references This European Standard incorporates 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 revi
24、sions of any of these publications apply to this European 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
25、 tightness testing. EN 1779:1999, Non-destructive testing Leak testing Criteria for method and technique selection. 3 Terms and definitions For the purposes of this European Standard, the terms and definitions given in EN 1330-8 apply. In this document the methods and techniques are referred to the
26、annex A of the EN 1779:1999. 4 Tracer gas method - Group A techniques (gas flowing into object) 4.1 Equipment and Material required for all group A techniques 4.1.1 Leak detector In this type of test, a leak detector (LD) of the mass spectrometer type (MSLD) according to the minimum requirements of
27、Table 1 is used. 4.1.2 Calibration leaks At least one calibration leak for discharge to vacuum or against atmospheric pressure shall be used. These are used for the direct calibration of the MLSD (if a built-in calibration leak does not exist) or for system calibration (response time, sensitivity).
28、If required, standard leaks shall be used. See Table 2. 4.1.3 Auxiliary pumping system An auxiliary pumping system should be used if: ? the object volume or desorption gas load are too large for the built-in pumps of the MSLD; ? the leakage rate to be measured is too large for the measurement range
29、of the MSLD. The auxiliary vacuum pumping system shall comply with the minimum requirements of Table 4. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13625:2001 (E) 5 4.1.4 Connections Pipes and valves of suitable conductance with a por
30、t for vacuum pressure measurement, previously tested for tightness so that they can not influence the test results, are required for: ? connection of the object to the MSLD; ? connection of the calibration leak to the system; ? connection of the object to the auxiliary pumping system (if necessary).
31、 There should be a device for discharging the tracer gas outside the test area. 4.1.5 Tracer gas Pure tracer gas or a known and homogeneous mixture containing tracer gas shall be supplied to ensure repeatability. 4.1.6 Test condition measurements Calibrated pressure gauges and thermometers are requi
32、red to monitor the object conditions. If required, ambient condition (pressure, temperature and humidity) shall also be measured. Response time shall be measured. 4.1.7 Cleaning and drying material and equipment Solvents or degreasing agents shall be available to clean the surfaces to be tested. Dry
33、ing is important to eliminate vapours that can increase the evacuation time or can interfere with tracer gas detection. 4.2 Vacuum technique 4.2.1 Vacuum technique total (A.1) 4.2.1.1 Hood or rigid chamber The hood can be fabricated from a plastic film that is able to enclose entirely the object. It
34、 should be leak-tight enough to keep the tracer gas concentration constant. The rigid chamber shall be leaktight and enclose the object entirely. It should allow easy handling of the test object. It shall be evacuable to purge the internal volume. Suitable crossing in the walls shall allow the conne
35、ctions. The chamber pressure shall be measured. NOTEThe enclosure should present a leakage rate 10 times less than the maximum allowed rate specified. 4.2.1.2 Time measurement If the test is performed using an accumulation technique, the time from the initial tracer gas application shall be measured
36、. 4.2.2 Vacuum technique partial (A.2) 4.2.2.1 Cups or partial hoods Parts of the outer surface of the object are covered to admit selectively the tracer gas to the areas under test. Cups shall have soft edges or gaskets to adhere as much as possible to the surface. The plastic hoods shall be sealed
37、, for example with adhesive tape. It should be leak-tight enough to keep the tracer gas concentration constant. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13625:2001 (E) 6 4.2.3 Vacuum technique (local) (A.3) 4.2.3.1 Spray gun A spra
38、y gun with regulating valve is needed. If a tracer gas mixture is required for the test, the mixture can be obtained using a proportioning spray gun. 4.2.3.2 Calibration leak A conductance leak, calibrated for discharge to vacuum shall be used to verify the response time and the signal amplitude at
39、the scanning speed. This calibration leak should be in the same range as the expected maximum leakage rate. 5 Tracer gas method - Group B techniques (gas flowing out of the object) 5.1 Equipment and materials required for all group B techniques 5.1.1 Leak detector Except for the Ammonia Technique (B
40、.1) a leak detector with recorder is required. The leak detector (except for bombing test) shall be able to sample at a relatively high pressure (20 kPa to 100 kPa). The MSLD shall have a regulating inlet valve or a sampling probe to adjust the inlet pressure to the maximum working pressure. 5.1.2 C
41、alibration leaks Calibration leaks for discharge to atmosphere shall be used. These leaks should have a leakage rate close to the maximum allowable in the case of acceptance test or close to the minimum rate in leak location. 5.1.3 Test condition measurements Calibrated pressure gauges are required
42、to monitor the object pressure. If necessary, overpressure protection devices shall be used to avoid damage to the object and danger to personnel. If required, the object temperature and ambient conditions (pressure, temperature and humidity) have also to be measured. Response and impregnation time
43、shall be measured. 5.1.4 Connections Piping system, with port for pressure - and, if necessary, temperature-measurement, previously tested for leak tightness, is required for: ? filling the object with tracer gas; ? connecting (if necessary) any enclosure to the LD and to the pumping system. Piping
44、system is also required to discharge the tracer gas outside the area where the test is being conducted. 5.1.5 Gases Pure tracer gas or a constant mixture containing tracer gas shall be supplied at the pressure required for the test. Other dry (or dried) gases are necessary for purging the object or
45、the enclosures. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:44:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13625:2001 (E) 7 5.2 Ammonia technique (B.1) 5.2.1 Chemical material The reagents are generally colour-changing compounds, either in liquid form or supported on paper band. T
46、heir reactivity shall be verified before the test. For preparation after cleaning, passivation using dilute nitric acid (a volume fraction of 5 %) is required. The application of the reagent is made using a spray gun or a brush. Warm, dry air or inert gas, is needed to dry the applied reagent. The p
47、aper band is fixed with adhesive tape. The tracer gas shall be dry ammonia or a certified mixture of ammonia in inert gas, having a pressure and concentration sufficient to meet the test specifications. 5.2.2 Drying, pressurization, ammonia discharge A suitable pumping system is necessary for drying
48、 after the cleaning-passivation, for pressurization with ammonia mixture and for the removal of tracer gas from the system. 5.2.3 Pressure and concentration control An absolute gauge with a full scale range of 0,4 Mpa to 0,5 MPa is needed for evacuation/pressurization monitoring. Ammonia concentrati
49、on shall be checked using reactive tubes in the following ranges: ? concentration for test : range1 % to 10 % .10 % to 100 %; ? concentration after purging: range5 10-6 to 500 10-6 .0,05 10-6 to 5 10-6. pH Indicating equipment is required to check the wastes before the discharge. 5.2.4 Ammonia disposal equipment Equipment to discharge and treat used ammonia, in accordance with local regulations, shall be used. 5.2.5 Illumination and visual equipment The reagent-covered surface shall be examined with white light, either directly or with instrumen
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