1、BS EN 14986:2017Design of fans workingin potentially explosiveatmospheresBSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS EN 14986:2017 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 14986:2017.It supersedes BS EN 14986:2007 w
2、hich is withdrawn.The UK participation in its preparation was entrusted to Technical Committee EXL/23, Explosion and fire precautions in industrial and chemical plant.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport t
3、o include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2017.Published by BSI Standards Limited 2017ISBN 978 0 580 85162 9 ICS 23.120; 29.260.20 Compliance with a British Standard cannot confer immunity from legal obl
4、igations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 January 2017.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS EN 14986:2017EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 14986 January 2017 ICS 23.
5、120 Supersedes EN 14986:2007English Version Design of fans working in potentially explosive atmospheres Conception des ventilateurs pour les atmosphres explosibles Konstruktion von Ventilatoren fr den Einsatz in explosionsgefhrdeten Atmosphren This European Standard was approved by CEN on 30 October
6、 2016. 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 references concerning such national standards may be obtain
7、ed on application to the CEN-CENELEC 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 into its own language and notified to the CEN-
8、CENELEC Management Centre has the same status as the official versions. CEN members 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,
9、Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management
10、Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 14986:2017 EBS EN 14986:2017EN 14986:2017 (E) 2 Contents Page European foreword . 4 Introduction 5 1 Scope 6 2 Normative references 7 3
11、Terms and definitions . 7 4 Requirements for all fans . 8 4.1 Ignition hazard assessment . 8 4.1.1 General 8 4.1.2 Normal operating conditions 8 4.1.3 Expected malfunction 8 4.1.4 Rare malfunction . 8 4.2 Assignment of categories . 8 4.3 Temperatures . 9 4.3.1 General 9 4.3.2 Maximum surface tempera
12、ture . 9 4.3.3 Temperature of the conveyed atmosphere (flammable or not) . 10 4.4 Mechanical design criteria 10 4.4.1 General . 10 4.4.2 Clearance between rotating elements and the fan casing . 10 4.5 Casing . 11 4.5.1 General . 11 4.5.2 Gas tightness 11 4.6 Impellers . 11 4.7 Materials for rotating
13、 and stationary parts of fans 11 4.7.1 General . 11 4.7.2 Permissible material pairings . 12 4.8 Linings and tip extensions 22 4.9 Vibration . 22 4.10 Earthing conducting parts 23 4.11 Electrostatic charges . 23 4.12 Electrical equipment . 23 4.13 Prevention of deposits inside the fan . 23 4.14 Shaf
14、t seals . 24 4.15 Bearings . 24 4.16 Power transmission systems . 24 4.17 Clutches and couplings . 24 4.18 Brakes and braking systems 24 4.19 Impeller-shaft attachment 24 4.20 Corrosion of fan components . 28 4.21 Fire resistance . 28 4.22 Protection against foreign particles 28 5 Additional require
15、ments for category 2 28 5.1 General . 28 5.2 Impeller-shaft attachment 28 5.3 Vibration . 29 BS EN 14986:2017EN 14986:2017 (E) 3 5.4 Material pairings . 29 6 Category 1 fans for specific use with a gaseous explosive atmosphere as a conveyed atmosphere (flammable or not) 29 6.1 General requirements .
16、 29 6.2 Flame arresters . 29 6.2.1 General . 29 6.2.2 Stabilized burning 29 6.3 Casings 30 6.3.1 General . 30 6.3.2 Gas tightness . 30 7 Information for use 30 7.1 General . 30 7.2 Accompanying documentation 30 7.3 Markings 32 Annex A (normative) Additional requirements for category 1 G fans 33 A.1
17、General . 33 A.2 Flame transmission test . 33 A.3 Pressure test . 34 Annex B (informative) Classification of requirements for the different categories 35 Annex C (informative) Checklist for verification of the safety requirements and/or protective measures 39 C.1 General . 39 C.2 All categories 39 C
18、.3 Category 2 Gas and dust 40 C.4 Category 1 Gas 40 Annex D (informative) Examples of types of fans showing ignition minimizing features 41 Annex E (normative) List of significant hazards . 46 Annex ZA (informative) Relationship between this European Standard and the Essential Requirements of EU Dir
19、ective 2014/34/EU 50 Bibliography . 51 BS EN 14986:2017EN 14986:2017 (E) 4 European foreword This document (EN 14986:2017) has been prepared by Technical Committee CEN/TC 305 “Potentially explosive atmospheres - Explosion prevention and protection”, the secretariat of which is held by DIN. This docu
20、ment supersedes EN 14986:2007. 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 July 2017, and conflicting national standards shall be withdrawn at the latest by July 2017. Attention is drawn to th
21、e possibility that some of the elements of this document may be the subject of patent rights. CEN shall not be held responsible for identifying any or all such patent rights. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Associati
22、on, and supports essential requirements of EU Directive 2014/34/EU. For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this document. According to the CEN-CENELEC Internal Regulations, the national standards organisations of the following countries are boun
23、d to implement this European Standard: 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, Portugal
24、, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 14986:2017EN 14986:2017 (E) 5 Introduction This European Standard is a type C standard as stated in EN ISO 12100. The machinery concerned and the extent to which hazards, hazardous situations and
25、events are covered and indicated in the scope of this European Standard. When provisions of this type C standard are different from those, which are stated in type A or B standards, the provisions of this type C standard take precedence over the provisions of the other standards, for machines that h
26、ave been designed and built according to the provisions of this type C standard. BS EN 14986:2017EN 14986:2017 (E) 6 1 Scope 1.1 This European Standard specifies the constructional requirements for fans constructed to Group II G (of explosion groups IIA, IIB and hydrogen) categories 1, 2 and 3, and
27、Group II D categories 2 and 3, intended for use in explosive atmospheres. NOTE 1 Operation conditions for the different categories of fans used in this European Standard are defined in Clause 4. NOTE 2 Technical requirements for category 1 D fans are not given in this document. Where explosive dust
28、atmospheres are regularly conveyed, explosion protection measures as described in EN 11271 are required if this specific us is needed. 1.2 This European Standard does not apply to group I fans (fans for mining), cooling fans or impellers on rotating electrical machines, cooling fans or impellers on
29、internal combustion engines. NOTE 1 Requirements for group I fans are given in EN 1710. NOTE 2 The requirements for electrical parts are covered by references to electrical equipment standards. 1.3 This European Standard specifies requirements for design, construction, testing and marking of complet
30、e fan units intended for use in potentially explosive atmospheres in air containing gas, vapour, mist and/or dusts. Such atmospheres may exist inside (the conveyed atmosphere (flammable or not), outside, or inside and outside of the fan. 1.4 This European Standard is applicable to fans working in am
31、bient atmospheres and with normal atmospheric conditions at the inlet, having absolute pressures ranging from 0,8 bar to 1,1 bar, and temperatures ranging from 20 C to +60 C, and maximum volume fraction of 21 % oxygen content, and an aerodynamic energy increase of less than 25 kJ/kg. NOTE 1 25 kJ/kg
32、 is equivalent to 30 kPa at inlet density of 1,2 kg/m3. This European Standard may also be helpful for the design, construction, testing and marking of fans intended for use in atmospheres outside the validity range stated above or in cases where other material pairings need to be used. In this case
33、, the ignition risk assessment, ignition protection provided, additional testing (if necessary), manufacturers marking, technical documentation and instructions to the user, should clearly demonstrate and indicate the equipments suitability for the conditions the fan may encounter. This European Sta
34、ndard should not apply to integral fans as a part of Diesel engines, vehicles or electric motors. NOTE 2 Where undated references are used in the body of the standard the latest edition applies. BS EN 14986:2017EN 14986:2017 (E) 7 2 Normative references The following documents, in whole or in part,
35、are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 1127-1:2011, Explosive atmospheres - Explosion pre
36、vention and protection - Part 1: Basic concepts and methodology EN ISO 80079-36:2016, Explosive atmospheres - Part 36: Non-electrical equipment for explosive atmospheres - Basic method and requirements (ISO 80079-36:2016) EN ISO 80079-37:2016, Explosive atmospheres - Part 37: Non-electrical equipmen
37、t for explosive atmospheres - Non-electrical type of protection constructional safety c, control of ignition sources b, liquid immersion k (ISO 80079-37:2016) EN 60079-0, Explosive atmospheres - Part 0: Equipment - General requirements EN ISO 5801, Industrial fans - Performance testing using standar
38、dized airways (ISO 5801) EN ISO 11925-2, Reaction to fire tests - Ignitability of products subjected to direct impingement of flame - Part 2: Single-flame source test (ISO 11925-2) EN ISO 12100, Safety of machinery - General principles for design - Risk assessment and risk reduction (ISO 12100) EN I
39、SO 16852:2010, Flame arresters - Performance requirements, test methods and limits for use (ISO 16852:2008, including Cor 1:2008 and Cor 2:2009) EN ISO 13349:2010, Fans - Vocabulary and definitions of categories (ISO 13349:2010) ISO 14694:2003, Industrial fans Specifications for balance quality and
40、vibration levels ISO 14694:2003/AMD1, Industrial fans Specifications for balance quality and vibration levels 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 1127-1:2011, EN ISO 80079-36:2016 and the following apply. 3.1 externally mounted flame arres
41、ter flame arrester consisting of a flame arrester housing and flame arrester elements mounted as a separate equipment on the fan 3.2 integrated flame arrester flame arrester consisting of a flame arrester housing and flame arrester elements where the flame arrester housing is part of the fan housing
42、 3.3 contact diameter diameter of a rotating part at the point where it can contact a stationary part BS EN 14986:2017EN 14986:2017 (E) 8 4 Requirements for all fans 4.1 Ignition hazard assessment 4.1.1 General A list of hazards considered is given in Annex D. These include hazards inside and outsid
43、e the fan. Where additional hazards could occur an ignition hazard assessment according to EN ISO 80079-36 shall be carried out. For the purposes of fans made according to this European Standard the following operational conditions shall be used as a basis for the ignition hazard assessment and for
44、the assignment of a fan to a particular category. Release of flammable material shall be considered in the ignition hazard assessment for the outside of the fan, see 4.3. 4.1.2 Normal operating conditions Normal operating conditions shall be considered to occur in situations where the fan performs i
45、ts intended use within its design parameters. This includes conditions during start up and shut down. (See also EN ISO 12100.) For the purposes of fans made according to this European Standard failures (such as a breakdown of seals, flange gaskets or releases of substances caused by accidents) which
46、 involve repair or shut-down are not considered to be part of normal operation. 4.1.3 Expected malfunction An expected malfunction shall be considered to be a failure or fault in a fan which normally occurs in practice. In addition an expected malfunction shall be considered to occur when a fan or i
47、ts components do not perform their intended functions. For the purposes of fans made according to this European Standard this can happen for a variety of reasons, including: a) variation in the properties or dimensions of the fan assembly (e.g. warping of the casing); b) disturbance to or failure of
48、 the power supply or other services; c) unnoticed long time operation with defective bearing and leading to contact between impeller and housing; d) release of the impeller blade by vibrations over an extended period. 4.1.4 Rare malfunction A rare malfunction is a type of malfunction which is known
49、to happen but only in rare instances. Two independent expected malfunctions which, separately, would not create an ignition hazard but which, in combination, do create an ignition hazard, are regarded as a single rare malfunction. 4.2 Assignment of categories A fan may have a different category for the inside and outside. Fans which may be used both to convey an explosive gas, vapour, mist or dust atmosphere and/or are located in an explosive gas, vapour, mist or dust atmosphere are assigned categories internally and externally depending on the
