Non-destructive testing - Leak test - Guide to the selection of instrumentation for the measurement of gas leakage

This European Standard specifies criteria for the selection of equipment for the leak detection methods described in 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).

Zerstörungsfreie Prüfung - Dichtheitsprüfung - Anleitung zur Auswahl von Geräten zur Messung von Gasleckagen

Diese Europäische Norm legt Kriterien zur Auswahl von Ausrüstungen für die Dichtheitsprüfmethoden, die in EN 1779 beschrieben sind, fest. Die Mindestanforderungen an die benutzten Geräte werden zusätzlich als Richtlinie für das Prüfpersonal angegeben. Die endgültige Auswahl eines Gerätes für eine bestimmte Prüfung liegt jedoch in der Verantwortung eines qualifizierten Bedieners (mindestens Stufe 2-Qualifikation - siehe EN 473).

Essais non destructifs - Contrôle d'étanchéité - Guide pour la sélection des instruments utilisés pour le mesurage des fuites gazeuses

La présente Norme européenne spécifie les criteres de sélection des matériels utilisés avec les méthodes de détection de fuites décrites dans l'EN 1779. Les exigences minimales relatives a la performance des appareils utilisés sont également données comme directive pour le personnel chargé de réaliser les contrôles. La sélection précise d'un appareil pour un contrôle donné releve toutefois de la responsabilité d'un opérateur qualifié (niveau 2 de qualification au minimum - voir l'EN 473).

Neporušitveno preskušanje – Preskus tesnosti – Vodilo pri izbiri naprav za meritve puščanja plinov

General Information

Status
Published
Publication Date
29-Feb-2004
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
01-Mar-2004
Due Date
01-Mar-2004
Completion Date
01-Mar-2004

Buy Standard

Standard
EN 13625:2004
English language
19 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Zerstörungsfreie Prüfung - Dichtheitsprüfung - Anleitung zur Auswahl von Geräten zur Messung von GasleckagenEssais non destructifs - Contrôle d'étanchéité - Guide pour la sélection des instruments utilisés pour le mesurage des fuites gazeusesNon-destructive testing - Leak test - Guide to the selection of instrumentation for the measurement of gas leakage19.100Neporušitveno preskušanjeNon-destructive testingICS:Ta slovenski standard je istoveten z:EN 13625:2001SIST EN 13625:2004en01-marec-2004SIST EN 13625:2004SLOVENSKI
STANDARD



SIST EN 13625:2004



EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 13625December 2001ICS 19.100English versionNon-destructive testing - Leak test - Guide to the selection ofinstrumentation for the measurement of gas leakageEssais non destructifs - Contrôle d'étanchéité - Guide pourla sélection des instruments utilisés pour le mesurage desfuites gazeusesZerstörungsfreie Prüfung - Dichtheitsprüfung - Anleitung zurAuswahl von Geräten zur Messung von GasleckagenThis 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 EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards 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 translationunder the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the officialversions.CEN members 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 STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2001 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 13625:2001 ESIST EN 13625:2004



EN 13625:2001 (E)2ContentspageForeword.31Scope.42Normative references.43Terms and definitions.44Tracer gas method - Group A techniques (gas flowing into object).44.1Equipment and Material required for all group A techniques.44.2Vacuum technique.55Tracer gas method - Group B techniques (gas flowing out of the object).65.1Equipment and materials required for all group B techniques.65.2Ammonia technique (B.1).75.3Vacuum box technique, for large enclosures or open walls (B.2.1, B.2.2).75.4Enclosure techniques (B.3, B.6).85.5Direct sample probing technique (B.4).85.6Pressurizing-Evacuation technique (B.5).85.7Sealed object by vacuum technique (B.6).96Bubble test method - Group C techniques.96.1Immersion technique (C.1).96.2Liquid application technique (C.2).106.3Liquid technique with vacuum box.107Total pressure change method - Group D techniques.117.1Equipment and Material required for all group D techniques.117.2Pressure decay technique (D.1).117.3Pressure rise technique (D.2).127.4Pressure change test (bell pressure change – D.3).127.5Flow measurement technique (D.4).13Bibliography.19SIST EN 13625:2004



EN 13625:2001 (E)3ForewordThis European Standard has been prepared by Technical Committee CEN/TC 138 "Non-destructive testing", thesecretariat 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 orby endorsement, at the latest by June 2002, and conflicting national standards shall be withdrawn at the latest byJune 2002.According to the CEN/CENELEC Internal Regulations, the national standards organizations of the followingcountries 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 the United Kingdom.SIST EN 13625:2004



EN 13625:2001 (E)41 ScopeThis European Standard specifies criteria for the selection of equipment for the leak detection methods described inEN 1779. The minimum requirements for the performance of the instruments used are also given as a guideline forpersonnel involved in testing. The definite selection of an instrument for a given test is within the responsibility of aqualified operator (at minimum level 2 qualification – see EN 473).2 Normative referencesThis European Standard incorporates by dated or undated reference, provisions from other publications. Thesenormative references are cited at the appropriate places in the text, and the publications are listed hereafter. Fordated references, subsequent amendments to or revisions of any of these publications apply to this Europeanstandard only when incorporated in it by amendment or revision. For undated references the latest edition of thepublication referred to applies (including amendments).EN 1330-8, Non-destructive testing – Terminology – Part 8: Terms used in leak tightness testing.EN 1779:1999, Non-destructive testing – Leak testing – Criteria for method and technique selection.3 Terms and definitionsFor 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 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 techniques4.1.1 Leak detectorIn this type of test, a leak detector (LD) of the mass spectrometer type (MSLD) according to the minimumrequirements of Table 1 is used.4.1.2 Calibration leaksAt least one calibration leak for discharge to vacuum or against atmospheric pressure shall be used. These areused for the direct calibration of the MLSD (if a built-in calibration leak does not exist) or for system calibration(response time, sensitivity). If required, standard leaks shall be used. See Table 2.4.1.3 Auxiliary pumping systemAn 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 of the MSLD.The auxiliary vacuum pumping system shall comply with the minimum requirements of Table 4.SIST EN 13625:2004



EN 13625:2001 (E)54.1.4 ConnectionsPipes and valves of suitable conductance with a port for vacuum pressure measurement, previously tested fortightness 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).There should be a device for discharging the tracer gas outside the test area.4.1.5 Tracer gasPure tracer gas or a known and homogeneous mixture containing tracer gas shall be supplied to ensurerepeatability.4.1.6 Test condition measurementsCalibrated pressure gauges and thermometers are required to monitor the object conditions. If required, ambientcondition (pressure, temperature and humidity) shall also be measured. Response time shall be measured.4.1.7 Cleaning and drying material and equipmentSolvents or degreasing agents shall be available to clean the surfaces to be tested. Drying is important to eliminatevapours that can increase the evacuation time or can interfere with tracer gas detection.4.2 Vacuum technique4.2.1 Vacuum technique total (A.1)4.2.1.1 Hood or rigid chamberThe hood can be fabricated from a plastic film that is able to enclose entirely the object. It should be leak-tightenough 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 connections. Thechamber 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 measurementIf the test is performed using an accumulation technique, the time from the initial tracer gas application shall bemeasured.4.2.2 Vacuum technique partial (A.2)4.2.2.1 Cups or partial hoodsParts of the outer surface of the object are covered to admit selectively the tracer gas to the areas under test. Cupsshall have soft edges or gaskets to adhere as much as possible to the surface.The plastic hoods shall be sealed, for example with adhesive tape. It should be leak-tight enough to keep the tracergas concentration constant.SIST EN 13625:2004



EN 13625:2001 (E)64.2.3 Vacuum technique (local) (A.3)4.2.3.1 Spray gunA spray gun with regulating valve is needed. If a tracer gas mixture is required for the test, the mixture can beobtained using a proportioning spray gun.4.2.3.2 Calibration leakA conductance leak, calibrated for discharge to vacuum shall be used to verify the response time and the signalamplitude at 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 techniques5.1.1 Leak detectorExcept for the Ammonia Technique (B.1) a leak detector with recorder is required. The leak detector (except forbombing test) shall be able to sample at a relatively high pressure (20 kPa to 100 kPa). The MSLD shall have aregulating inlet valve or a sampling probe to adjust the inlet pressure to the maximum working pressure.5.1.2 Calibration leaksCalibration leaks for discharge to atmosphere shall be used. These leaks should have a leakage rate close to themaximum allowable in the case of acceptance test or close to the minimum rate in leak location.5.1.3 Test condition measurementsCalibrated pressure gauges are required to monitor the object pressure. If necessary, overpressure protectiondevices shall be used to avoid damage to the object and danger to personnel. If required, the object temperatureand ambient conditions (pressure, temperature and humidity) have also to be measured.Response and impregnation time shall be measured.5.1.4 ConnectionsPiping system, with port for pressure - and, if necessary, temperature-measurement, previously tested for leaktightness, is required for: filling the object with tracer gas; connecting (if necessary) any enclosure to the LD and to the pumping system.Piping system is also required to discharge the tracer gas outside the area where the test is being conducted.5.1.5 GasesPure 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 the enclosures.SIST EN 13625:2004



EN 13625:2001 (E)75.2 Ammonia technique (B.1)5.2.1 Chemical materialThe reagents are generally colour-changing compounds, either in liquid form or supported on paper band. Theirreactivity shall be verified before the test.For preparation after cleaning, passivation using dilute nitric acid (a volume fraction of 5 %) is required. Theapplication of the reagent is made using a spray gun or a brush. Warm, dry air or inert gas, is needed to dry theapplied reagent. The paper 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 andconcentration sufficient to meet the test specifications.5.2.2 Drying, pressurization, ammonia dischargeA suitable pumping system is necessary for drying after the cleaning-passivation, for pressurization with ammoniamixture and for
the removal of tracer gas from the system.5.2.3 Pressure and concentration controlAn absolute gauge with a full scale range of 0,4 Mpa to 0,5 MPa is needed for evacuation/pressurizationmonitoring.Ammonia concentration shall be checked using reactive tubes in the following ranges: concentration for test : range.1 % to 10 %.10 % to 100 %; concentration after purging: range.5 × 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 equipmentEquipment to discharge and treat used ammonia, in accordance with local regulations, shall be used.5.2.5 Illumination and visual equipmentThe reagent-covered surface shall be examined with white light, either directly or with instruments able to showspots larger than 1 mm. A minimum illumination of 350 lx shall be attained and measured.5.3 Vacuum box technique, for large enclosures or open walls (B.2.1, B.2.2)5.3.1 Vacuum boxThe rigid vacuum box shall have a soft seal to adhere as effectively as possible to the object wall. The leak-tightness of this seal is very important to increase the test sensitivity and to minimize the inlet of contaminated airfrom the ambient.5.3.2 Pumping systemThe pumping system shall be able to achieve and maintain the vacuum box pressure at a specified level.SIST EN 13625:2004



EN 13625:2001 (E)85.3.3 Cups or spray gunFor open objects the tracer gas is applied on the opposite side of the wall using cups, bags or a spray gun.5.4 Enclosure techniques (B.3, B.6)5.4.1 Tight enclosureThe enclosure can be a rigid chamber or a plastic bag, it shall entirely contain the object, and, allow for easyhandling. For leakage rate measurement, the internal free volume shall be known and this is best achieved using arigid chamber.The tightness of the enclosure shall be previously verified. The maximum allowed leakage rate shall be related tothe test sensitivity.Suitable flange in the walls shall allow the connections of the chamber to the LD, to a known leak, to the pumpingsystem and a suitable feed through may be needed to connect the object to the tracer gas supply. The chamberpressure shall be monitored.NOTEThe enclosure should have a leakage rate 10 times lower than the specified maximum allowable rate for the testobject.5.4.2 TimeThe tracer gas accumulation time shall be measured.5.4.3 Pumping systemA pumping system is used to evacuate the rigid chamber for purging. For sealed object that cannot support specificdifferential pressure, it shall be able to achieve and maintain the tight chamber pressure at the specified vacuumlevel.5.5 Direct sample probing technique (B.4)The sampling probe should be desig
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.