1、BSI Standards PublicationPD CEN/TR 16793:2016Guide for the selection, application and use of flame arrestersPD CEN/TR 16793:2016 PUBLISHED DOCUMENTNational forewordThis Published Document is the UK implementation of CEN/TR 16793:2016.The UK participation in its preparation was entrusted to Technical
2、 Committee EPL/278, Potentially explosive atmospheres - Explosion prevention and protection.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible
3、 for its correct application. The British Standards Institution 2016.Published by BSI Standards Limited 2016ISBN 978 0 580 85209 1 ICS 03.220.01; 35.240.60 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the
4、Standards Policy and Strategy Committee on 31 January 2016.Amendments/corrigenda issued since publicationDate Text affectedTECHNICAL REPORT RAPPORT TECHNIQUE TECHNISCHER BERICHT CEN/TR 16793 January 2016 ICS 23.060.40; 13.220.99 English Version Guide for the selection, application and use of flame a
5、rresters Guide pour la slection, lapplication et lutilisation des arrte-flammes Richtline frdie Auswahl, die Anwendung und den Einsatz von Flammendurchschlagssicherungen This Technical Report was approved by CEN on 22 December 2014. It has been drawn up by the Technical Committee CEN/TC 305. CEN mem
6、bers are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portu
7、gal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey andUnited Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2016 CEN All rights of exploitation in any for
8、m and by any means reserved worldwide for CEN national Members. Ref. No. CEN/TR 16793:2016 EPD CEN/TR 16793:20168.2 Safety information . 30 8.3 Checking and installing . 30 8.4 Inspection and maintenance intervals . 31 8.5 Liquid seal flame arrester . . 31 9 Commissioning checklist . . 32 Bibliograp
9、hy 33 CEN/TR 16793:2016 (E)PD CEN/TR 16793:2016European foreword This document (CEN/TR 16793:2016) has been prepared by Technical Committee CEN/TC 305“Potentially explosive atmospheres - Explosion prevention and protection”, the secretariat of which isheld by DIN. This document has been prepared und
10、er a mandate given to CEN by the European Commission and theEuropean Free Trade Association. Attention is drawn to the possibility that some of the elements of this document may be the subject ofpatent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patentrig
11、hts. CEN/TR 16793:2016 (E)PD CEN/TR 16793:2016Introduction The document provided is general in nature and for specific applications further expert advice shouldbe sought. In addition to the content of operating manuals from manufacturers, the local accident preventionregulations, environmental prote
12、ction and general safety provisions for the devices area of use, as wellas relevant laws and national directives, this paper will support the user for a proper use of flamearresters. In Europe, the “Directive 2014/34/EU on equipment and protective systems intended for use inpotentially explosive atm
13、ospheres” (ATEX Atmosphres Explosibles) is mandatory for the productionand test intended for use of products in potentially explosive atmospheres. Flame arresters are definedas a Protective System. Flame arresters should be tested according to EN ISO 16852, Flame arresters Performance requirements,
14、test methods and limits for use, to fulfill the health and safety requirements of this directive. Flame arresters are subjected to an EC type examination and are designed for use in areas at risk fromexplosion. The Directive 1999/92/EC of the European Parliament and of the Council of 16 December 199
15、9 onminimum requirements for improving the safety and health protection of workers potentially at riskfrom explosive atmospheres - gives the minimum requirements for the improvement of healthprotection and safety of employers who could be endangered by explosive atmospheres. The mainissues are asses
16、sment of explosion risk, zone classification and the explosion protection documents(including requirements for personnel to do engineering, equipment selection, installation,maintenance, repair, etc.). National regulations and/or codes relating to specific industries or applications may exist which
17、have tofollowed. Flame arresters are required to protect against many types of explosion events within equipment. The safety obtained depends heavily upon correct choice, installation and maintenance of the flamearrester. This cannot be achieved without responsible, informed management. CEN/TR 16793
18、:2016 (E)PD CEN/TR 16793:20161 Scope This Technical Report is aimed primarily at persons who are responsible for the safe design andoperation of installations and equipment using flammable liquids, vapours or gases. This document applies to both industrial and mining applications This document descr
19、ibes possible risks and gives proposals for the protection against these risks by theuse of flame arresters. This document gives some guidance to choice of flame arresters according to EN ISO 16852 for differentcommon scenarios and it gives best practice for the installation and maintenance of these
20、 flamearresters. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and areindispensable for its application. For dated references, only the edition cited applies. For undatedreferences, the latest edition of the referenced document (incl
21、uding any amendments) applies. EN 60079-20-1, Explosive atmospheres Part 20-1: Material characteristics for gas and vapourclassification Test methods and data (IEC 60079-20-1) EN ISO 16852:2010, Flame arresters Performance requirements, test methods and limits for use (ISO16852:2008, including Cor 1
22、:2008 and Cor 2:2009)EN ISO 28300:2008, Petroleum, petrochemical and natural gas industries Venting of atmospheric andlow-pressure storage tanks (ISO 28300:2008)3 Terms, definitions and abbreviated terms 3.1 Terms and definitions For the purposes of this document, the following terms and definitions
23、 apply. 3.1.1 atmospheric condition pressure ranging from 80 kPa to 110 kPa (0,8 bar to 1,1 bar); temperatures ranging from -20 C to+60 C 3.1.2 end-of-line flame arrester flame arrester that is fitted with one pipe connection only 3.1.3explosion abrupt oxidation or decomposition reaction producing a
24、n increase in temperature, pressure, or in bothsimultaneously 3.1.4explosion groupEx.G ranking of flammable gas-air mixtures with respect to the MESG Note 1 to entry: See EN ISO 16852:2010, 3.12.2. CEN/TR 16793:2016 (E)PD CEN/TR 16793:20163.1.5explosion-pressure-resistant property of vessels and equ
25、ipment designed to withstand the expected explosion pressure withoutbecoming permanently deformed 3.1.6explosion-pressure-shock resistant property of vessels and equipment designed to withstand the expected explosion pressure withoutrupturing, but allowing permanent deformation 3.1.7deflagration exp
26、losion propagating at subsonic velocity SOURCE: EN ISO 16852:2010, 3.8 3.1.8detonation explosion propagating at supersonic velocity and characterized by a shock wave SOURCE: EN ISO 16852:2010, 3.9 3.1.9 stable detonation detonation progressing through a confined system without significant variation
27、of velocity and pressurecharacteristics Note 1 to entry: For the atmospheric conditions, test mixtures and test procedures of this InternationalStandard, typical velocities range between 1 600 m/s and 2 200 m/s. SOURCE: EN ISO 16852:2010, 3.10 3.1.10 unstable detonation detonation during the transit
28、ion of a combustion process from a deflagration into a stable detonation Note 1 to entry: The transition occurs in a limited spatial zone, where the velocity of the combustion wave is notconstant and where the explosion pressure is significantly higher than in a stable detonation. The position of th
29、istransition zone depends, amongst other factors, on pipe diameter, pipe configuration, test gas and explosiongroup. SOURCE: EN ISO 16852:2010, 3.11 3.1.11 flame arrester device fitted to the opening of an enclosure, or to the connecting pipe work of a system of enclosures,and whose intended functio
30、n is to allow flow but prevent the transmission of flame SOURCE: EN ISO 16852:2010, 3.1 3.1.12 flame arrester element part of a flame arrester whose principal function is to prevent flame transmission SOURCE: EN ISO 16852:2010, 3.3 CEN/TR 16793:2016 (E)PD CEN/TR 16793:20163.1.13 in-line flame arrest
31、er flame arrester that is fitted with two pipe connections, one on each side of the flame arrester SOURCE: EN ISO 16852:2010, 3.22 3.1.14mixture used to represent any mixtures of gas and/or product vapour/air 3.1.15product equipment, protective systems, safety devices, components and their combinati
32、ons 3.1.16protected side side of the plant component to be protected 3.1.17protective system autonomous devices to stop an explosion immediately and/or limit the effects of explosion flames andpressures 3.1.18 stabilized burning steady burning of a flame stabilized at, or close to, the flame arreste
33、r element short time (max. 30minutes) or endurance burning (for unlimited time) 3.1.19unprotected side ignition source side 3.1.20restriction reduction of the diameter of the pipe on the protected side of a flame arrester Note 1 to entry: For example, a restriction can be a not fully opened valve. 3
34、.2 Abbreviated terms DN nominal size of the connection of a device or pipe fittingLEL lower explosion limit of the explosion range Lrpipe length between flame arrester and restriction Lupipe length on the unprotected side, maximum allowable run-up length for installation p0maximum operational pressu
35、re T0maximum operational temperatureMESG maximum experimental safe gap safe gap measured in accordance with EN 60079-20-1 p/v valve pressure and vacuum relief vent valveUEL upper explosion limit of the explosion rangeNPSH net positive suction head CEN/TR 16793:2016 (E)PD CEN/TR 16793:2016Z0minminimu
36、m operational water seal immersion depth when the mixture flow displaces the waterfrom the immersion tubes, where Z0min ZRminZ0operational immersion depth, corresponding to Z0minplus the manufacturers recommended safety margin ZRminminimum water seal immersion depth at rest above the outlet openings
37、 of the immersion tubes ZRimmersion depth at rest, corresponding to ZRminplus the manufacturers recommended safety margin maxVsafe volume flow rate sVsafe volume flow rate including a safety margin 4 Explosion risks The following content is a summary of the non-binding guide to good practice for imp
38、lementing theEuropean Parliament and Council Directive 1999/92/EC 1. Three components are necessary at the same time for an explosion to occur. These are visualized in theso-called explosion triangle (see Figure 1). 1) Air (oxidizer) 2) Fuel (flammable gas) 3) Ignition Source (e.g. spark, hot surfac
39、e, etc.) Figure 1 Explosion triangle Fuel mixed with air in a suitable ratio (above LEL and below UEL) is called explosive atmosphere. Assessment of explosion risks is focused on: the likelihood that an explosive atmosphere will occur, and subsequently on the likelihood that sources of ignition will
40、 be present and become effective. Suitable methods for assessing the explosion risks associated with work processes or plant are thosewhich lend themselves to a systematic approach to checking plant and process safety. An analysis ismade of the existing sources of hazardous explosive atmospheres and
41、 the effective sources of ignitionwhich could occur at the same time. Explosion risks can in practice be assessed by means ofseven questions: CEN/TR 16793:2016 (E)PD CEN/TR 16793:20161) Are flammable substances present? 2) Can sufficient dispersal in air give rise to an explosive atmosphere? 3) Wher
42、e can explosive atmospheres occur? 4) Is the formation of a hazardous explosive atmosphere possible? 5) Is the formation of hazardous explosive atmospheres reliably prevented? 6) To what zones can the places with hazardous explosive atmospheres be assigned? 7) Is the ignition of hazardous explosive
43、atmospheres reliably prevented? Depending on the answers of these questions, it could be necessary to apply adequate explosionprotection measures. “Explosion protection measures“ mean all measures that prevent the formation ofhazardous explosive atmospheres, avoid the ignition of hazardous explosive
44、 atmospheres or mitigatethe effects of explosions. One of the possible measures is to use flame arresters. An idealized representation of the flame acceleration process is presented in Figure 2. Key X pipe L/D 3 deflagration IIB - IIC Y1 flame speed in m s-14 deflagration IIA IIB3 Y2 pressure in bar
45、 5 deflagration to detonation transition 1 flame speed 6 stable detonation 2 pressure Figure 2 Development of an explosion in a pipeline CEN/TR 16793:2016 (E)PD CEN/TR 16793:20165 Technical measures for explosion protection 5.1 General Priority shall be given to the prevention of the formation of ha
46、zardous explosive atmospheres. This canbe done by avoiding or reducing the use or by limiting the concentration of flammable substances.Preventing of hazardous explosive atmospheres can also be realized by inerting. If it is not possible to prevent the formation of a hazardous explosive atmosphere,
47、its ignition shall beavoided. This can be achieved by protective measures which avoid or reduce the probability of ignitionsources. The probability that a hazardous explosive atmosphere and a source of ignition will be present at thesame place and time is estimated and the extent of the measures req
48、uired is determined accordingly.This is done on the basis of the zone concept, from which the necessary precautions are derived. NOTE It is, however, recognized that there can be sources of ignition that cannot be determined with a highdegree of accuracy (e.g. an electrostatic discharge within a pip
49、e or a lightning strike). 5.2 Mitigation of the effects of explosion 5.2.1 General In many cases, it is not possible to avoid explosive atmospheres and sources of ignition with a sufficientdegree of certainty. Measures shall then be taken to limit the effects of an explosion to an acceptableextent. Such measures are: explosion-resistant design; explosion relief; explosion suppression; prevention of flame and explosion propagation. These explosion protection measures generally relate to mitigation of the hazardous effects
