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BRITISH STANDARDBS EN 14222:2003Stainless steel shell boilersThe European Standard EN 14222:2003 has the status of a British StandardICS 27.060.30?BS EN 14222:2003This British Standard was published under the authority of the Standards Policy and Strategy Committee on 14 May 2003 BSI 14 May 2003ISBN 0 580 41804 9 National forewordThis British Standard is the official English language version of EN 14222:2003.The UK participation in its preparation was entrusted to Technical Committee PVE/16,Shell boilers,which has the responsibility to:A list of organizations represented on this committee can be obtained on request to its secretary.Cross-referencesThe British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled“International Standards Correspondence Index”,or by using the“Search”facility of the BSI Electronic Catalogue or of British Standards Online.This publication does not purport to include all the necessary provisions of a contract.Users are responsible for its correct application.Compliance with a British Standard does not of itself confer immunity from legal obligations.aid enquirers to understand the text;present to the responsible international/European committee any enquiries on the interpretation,or proposals for change,and keep the UK interests informed;monitor related international and European developments and promulgate them in the UK.Summary of pagesThis document comprises a front cover,an inside front cover,the EN title page,pages 2 to 12,an inside back cover and a back cover.The BSI copyright date displayed in this document indicates when the document was last issued.Amendments issued since publicationAmd.No.DateCommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 14222April 2003ICS 27.060.30English versionStainless steel shell boilersChaudires tubes de fume en acier inoxydableEdelstahl-GrowasserraumkesselThis European Standard was approved by CEN on 21 February 2003.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,Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Slovakia,Spain,Sweden,Switzerland and UnitedKingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre:rue de Stassart,36 B-1050 Brussels 2003 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref.No.EN 14222:2003 EEN 14222:2003(E)2ContentspageForeword.31Scope.42Normative references.43Terms and definitions.44Materials.55Design.56Manufacture.57Inspection and testing.58Marking.59Requirements for equipment.59.1General.59.2Safeguards against excessive pressure.59.3Materials for valves,fittings,flanges and bolting.59.4Limiting devices and safety circuits.69.5Boiler heat supply.69.6Water level indication.69.7Steam pressure indication.79.8Drain and blowdown devices.89.9Valves for connections.89.10Feed water supply.89.11Feed water control.89.12Limiting devices.910Operational aspects of steam boilers.911Small steam boilers.9Annex A(informative)Operational aspects of steam boilers.10Annex ZA(informative)Clauses of this European Standard addressing essential safety requirementsof the Pressure Equipment Directive.11Bibliography.12w w w.b z f x w.c o mEN 14222:2003(E)3ForewordThis document(EN 14222:2003)has been prepared by Technical Committee CEN/TC 269 Shell and water-tubeboilers,the secretariat of which is held by DIN.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 October 2003,and conflicting national standards shall be withdrawn at the latestby October 2003.This document has been prepared under a mandate given to CEN by the European Commission and the EuropeanFree Trade Association,and supports essential requirements of EU Directive(s)Pressure Equipment Directive(PED)97/23/EC 1.For relationship with EU Directive(s),see informative annex ZA,which is an integral part of this document.This European Standard refers to EN 12953:Shell boilers and EN 13445:Unfired pressure vessels.Annex A is informative.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,Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Slovakia,Spain,Sweden,Switzerland and the United Kingdom.w w w.b z f x w.c o mEN 14222:2003(E)41 ScopeThis European Standard specifies requirements for electrically heated shell boilers manufactured from stainlesssteel specifically dedicated for generating steam for sterilizers and disinfectors.This European Standard covers only boilers that are heated by immersion heaters and which have a maximumallowable pressure(PS)of 6 bar,a maximum volume(V)of 1 000 litres and a product of PS x V not greater than3 000 bar x l.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 285:1996,Sterilisation Steam sterilizers Large sterilizers.EN 12953-1,Shell boilers Part 1:General.EN 12953-5,Shell boilers Part 5:Inspection during construction,documentation and marking of pressure partsof the boiler.EN 12953-6,Shell boilers Part 6:Requirements for equipment for the boiler.EN 12953-8,Shell boilers Part 8:Requirements for safeguards against excessive pressure.prEN 12953-9:1999,Shell boilers Part 9:Requirements for limiting devices and safety circuits of the boiler andaccessories.EN 13445-2:2002,Unfired pressure vessels Part 2:Materials.EN 13445-3,Unfired pressure vessels Part 3:Design.EN 13445-4,Unfired pressure vessels Part 4:Fabrication.EN 13445-5,Unfired pressure vessels Part 5:Inspection and testing.EN 60204-1,Safety of machinery Electrical equipment of machines Part 1:General requirements(IEC 60204-1:1997).3 Terms and definitionsFor the purposes of this European Standard,the terms and definitions given in EN 12953-1 and EN 12953-6 andthe following apply:3.1controlsdevices used for maintaining the variable to be controlled(e.g.water level,pressure,temperature)at a specificvalue(set point)3.2limitersdevice that,on reaching a fixed value(e.g.pressure,temperature,flow,water level)is used to interrupt and lock-out the heating energy supply and lock-out requires manual unlocking before restartw w w.b z f x w.c o mEN 14222:2003(E)53.3lock-outisolation of energy supply which requires a manual intervention to reinstate3.4functional checktesting of the safety device to ensure it performs its intended function4 MaterialsEach steam boiler shall be manufactured from materials in steel group 8 or 10 in accordance withEN 13445-2:2002,annex A.5 DesignEach steam boiler shall be designed in accordance with EN 13445-3.6 ManufactureEach steam boiler shall be manufactured in accordance with EN 13445-4.7 Inspection and testingEach steam boiler shall be inspected,tested and documented in accordance with EN 13445-5.8 MarkingThe requirements for marking shall be in accordance with EN 12953-5.9 Requirements for equipment9.1 GeneralThe following requirements for equipment for electrically heated stainless steel shell boilers are worked out on thebasis of EN 12953-6.9.2 Safeguards against excessive pressureEach steam boiler shall be equipped with safeguards against excessive pressure in accordance with EN 12953-8.In a deviation from EN 12953-8 the minimum inside diameter of the safety valve seat could be reduced to 8 mm.9.3 Materials for valves,fittings,flanges and boltingSteel materials for valves,fittings,flanges and bolting shall be in accordance with EN 13445-2.w w w.b z f x w.c o mEN 14222:2003(E)69.4 Limiting devices and safety circuits9.4.1Limiters shall be designed in addition to prEN 12953-9.In accordance with prEN 12953-9:1999,5.4.2 levelelectrode inclinations between 45 and 90 from the vertical shall be allowed provided that functional capabilityexaminations have proven successful.The electrical safety circuits shall be in accordance with EN 60204-1.9.4.2Functional checking of all limiters shall be possible at any time during operation e.g.by simulation whereappropriate.9.4.3If a limiter responds,the boiler shall automatically go to a safe condition and a signal shall be given toindicate boiler malfunction.9.4.4After manual resetting of a limiter lock-out,the boiler shall be put back into operation by manualintervention only.9.5 Boiler heat supply9.5.1The pressure of each boiler shall be controlled automatically by regulating the heating energy input.9.5.2Automatic start-up of the boiler and the system is permitted provided that equipment is installed to ensurethat start-up is conducted safely.Automatic restarting after normal shut-down shall not be considered a start-up.9.5.3A high temperature alarm device for shutting off the heating energy supply shall be provided.The alarmtemperature shall be determined by the manufacturer.9.5.4The electrical supply circuits and the safety of the control equipment shall conform to EN 60204-1.9.6 Water level indication9.6.1Each steam boiler shall have at least one independent means(independent from other equipment)ofindicating the water level,which shall be a gauge of transparent material directly connected to the boiler shell.9.6.2The gauge(s)shall be mounted so that the water level is visible through the transparent material at thelowest alarm level,i.e.at the lowest permissible water level(LWL),which shall be marked.The maximumpermissible water level,which shall be specified by the boiler manufacturer,shall be visible.The gauge shall becapable of showing a measurement of 15 mm below LWL.9.6.3The lowest permissible water level(LWL)of the boiler(see Figure 1),which shall be permanently andlegibly marked on the boiler shell and identified by the letters LWL,shall be at least 30 mm above the uppermostsurface of the immersion heaters HHS.w w w.b z f x w.c o mEN 14222:2003(E)7Key1Controlled water level2LWL3HHSFigure 1 Water level indication9.6.4Pipes and fittings connecting a water level gauge to a boiler shall be as short as possible and constructedso that no undrained pocket is formed between the boiler and the gauge.There shall be no outlet therefrom exceptfor regulators,steam pressure gauges and drains or other similar apparatus,which does not permit the escape of asignificant amount of steam.Pipes connecting a water level gauge to the boiler shall not be less than 8 mm bore.Where a chamber of a safetycontrol or alarm device is fitted to the water gauge or its piping,the connecting pipes between the boiler and thewater level gauge shall have a bore not less than 15 mm.9.6.5Where the water level gauge is a part of the boiler shell,the requirements of 9.6.4 shall not apply.9.7 Steam pressure indication9.7.1Each boiler shall have a steam pressure gauge in accordance with EN 285:1996,6.1.1.2,connected to thesteam space either directly or through the water level gauge column or its steam connection.9.7.2The steam pressure gauge shall be connected to a siphon or similar device of sufficient capacity to keepthe gauge tube filled with water.The pipe shall be of sufficient size and shall have provision for blowing through ifpossible.Alternatively the pressure line shall be fitted with an isolating membrane close to the boiler.The pressureline between the membrane and the gauge shall contain a non-compressible fluid.9.7.3Steam pressure gauge connections shall be made suitable for the design working pressure of the boiler.9.7.4Pressure gauges shall be graduated to indicate the pressure in bars.The maximum allowable pressureshall be indicated by a fixed and readily visible red mark on the pressure gauge.NOTEIn addition,the operating pressure and the safety valve set pressure may also be indicated.9.7.5Each boiler shall be provided with a valve connection for the special purpose of connecting a test gaugewhen the boiler is in service so that the accuracy of the boiler steam gauge can be ascertained.w w w.b z f x w.c o mEN 14222:2003(E)89.8 Drain and blowdown devices9.8.1Each boiler shall be fitted with drain valves placed at,or as near as practicable to,the lowest point of theapparatus.NOTEOn some boilers,drain valves may be used for blowdown purposes.9.8.2Where drain valves from two or more boilers are connected to a common discharge,two valves shall befitted to each drain line,one being of a non-return type to prevent the contents of one boiler passing to another.Asan alternative to the non-return valves an interlock system,enabling only one valve to be open at a time shall beallowed.9.8.3Taper-plug valves where fitted,shall be of the bolted cover type with separately packed glands.9.8.4Where drain valves are not self-closing or capable of being locked in the closed position,a further shut-offdevice shall be installed in the line.NOTEHaving the drain valve enclosed by a cabinet or an inspection door is included in the term being locked in a closed position.9.9 Valves for connections9.9.1 Steam outletsThe stop valve connecting the boiler to the steam pipe shall be attached directly to the boiler or shall be as near toit as practicable.The valve should preferably be of a type,which positively indicates whether it is open or closed.Where more than one boiler is connected to a common header or steam manifold,the steam connections for eachboiler shall be provided with two stop valves or some similar safety method shall be provided.NOTEIt is preferable that the valve nearest the boiler be a non-return type.9.9.2 Feed connectionsEach feed pipe to any boiler shall be provided with a non-return valve and a separate stop valve near the boiler.If the stop valve and non-return valve are not connected directly to each other,it shall be possible to relieve thepressure in the interconnecting