1、October 2011Translation by DIN-Sprachendienst.English price group 12No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS
2、 27.040!$td“1819265www.din.deDDIN EN 12952-4Water-tube boilers and auxiliary installations Part 4: In-service boiler life expectancy calculationsEnglish translation of DIN EN 12952-4:2011-10Wasserrohrkessel und Anlagenkomponenten Teil 4: Betriebsbegleitende Berechnung der LebensdauererwartungEnglisc
3、he bersetzung von DIN EN 12952-4:2011-10Chaudires tubes deau et installations auxiliaires Partie 4: Calculs de la dure de vie prvisible des chaudires en serviceTraduction anglaise de DIN EN 12952-4:2011-10SupersedesDIN EN 12952-4:2001-10www.beuth.deIn case of doubt, the German-language original shal
4、l be considered authoritative.Document comprises 23 pages0 .119 DIN EN 12952-4:2011-10 A comma is used as the decimal marker. National foreword This standard has been prepared by Technical Committee CEN/TC 269 “Shell and water-tube boilers” (Secretariat: DIN, Germany). The responsible German body in
5、volved in its preparation was the Normenausschuss Rohrleitungen und Dampfkesselanlagen (Piping and Boiler Plant Standards Committee), Working Committee NA 082-00-18 AA Dampfkesselanlagen. For more detailed information about the Normenausschuss Rohrleitungen und Dampfkesselanlagen (NARD), please visi
6、t www.nard.din.de. Amendments This standard differs from DIN EN 12952-4:2001-10 as follows: a) normative references have been updated; b) Equation (B.2) has been corrected; c) the numbering system for tables, drawings and equations has been modified; d) the standard has been editorially revised. Pre
7、vious editions DIN EN 12952-4: 2001-10 2 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 12952-4 July 2011 ICS 27.040 Supersedes EN 12952-4:2000English Version Water-tube boilers and auxiliary installations - Part 4: In-service boiler life expectancy calculations Chaudires tubes deau et install
8、ations auxiliaires - Partie 4: Calculs de la dure de vie prvisible des chaudires en service Wasserrohrkessel und Anlagenkomponenten - Teil 4: Betriebsbegleitende Berechnung der Lebensdauererwartung This European Standard was approved by CEN on 18 June 2011. CEN members are bound to comply with the C
9、EN/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 obtained on application to the CEN-CENELEC Management C
10、entre 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-CENELEC Management Centre has the same status as
11、the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Roma
12、nia, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12952-4:2011: EEUROPEAN COMMITTEE FOR STANDARDIZATION
13、 COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG EN 12952-4:2011 (E) 2 Contents Page Foreword . 31 Scope 52 Normative references 53 Terms and definitions . 54 Symbols and abbreviations 55 General . 56 Calculations . 5Annex A (informative) Calculation of in-service creep damage . 6Annex
14、 B (informative) Calculation of in-service fatigue damage . 10Annex C (informative) Significant technical changes between this European Standard and the previous edition . 20Bibliography 21DIN EN 12952-4:2011-10 EN 12952-4:2011 (E) 3 Foreword This document (EN 12952-4:2011) has been prepared by Tech
15、nical Committee CEN/TC 269 “Shell and water-tube boilers”, 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 or by endorsement, at the latest by January 2012, and conflicting national standards
16、 shall be withdrawn at the latest by January 2012. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 12952-4
17、:2000. Annex C provides details of significant technical changes between this European Standard and the previous edition. The European Standard EN 12952, concerning water-tube boilers and auxiliary installations, consists of the following parts: Part 1: General; Part 2: Materials for pressure parts
18、of boilers and accessories; Part 3: Design and calculation for pressure parts; Part 4: In-service boiler life expectancy calculations; Part 5: Workmanship and construction of pressure parts of the boiler; Part 6: Inspection during construction; documentation and marking of pressure parts of the boil
19、er; Part 7: Requirements for equipment for the boiler; Part 8: Requirements for firing systems for liquid and gaseous fuels for the boiler; Part 9: Requirements for firing systems for pulverized solid fuels for the boiler; Part 10: Requirements for safeguards against excessive pressure; Part 11: Req
20、uirements for limiting devices of the boiler and accessories; Part 12: Requirements for boiler feedwater and boiler water quality; Part 13: Requirements for flue gas cleaning systems; Part 14: Requirements for flue gas DENOX-systems using liquified pressurized ammonia and ammonia water solution; Par
21、t 15: Acceptance tests; Part 16: Requirements for grate and fluidized-bed firing systems for solid fuels for the boiler; CR 12952 Part 17: Guideline for the involvement of an inspection body independent of the manufacturer. DIN EN 12952-4:2011-10 EN 12952-4:2011 (E) 4 NOTE 1 A Part 18 on operating i
22、nstructions is currently in preparation. Although these parts may be obtained separately, it should be recognized that the parts are inter-dependent. As such, the design and manufacture of water-tube boilers requires the application of more than one part in order for the requirements of this Europea
23、n Standard to be satisfactorily fulfilled. NOTE 2 Part 4 and Part 15 are not applicable during the design, construction and installation stages. NOTE 3 A “Boiler Helpdesk“ has been established in CEN/TC 269 which may be contacted for any questions regarding the application of European Standards seri
24、es EN 12952 and EN 12953, see the following website: http:/www.boiler-helpdesk.din.de According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech R
25、epublic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. DIN EN 12952-4:2011-10 EN 12952-4:2011 (E) 5 1 S
26、cope This European Standard is applicable to water-tube boilers as defined in EN 12952-1:2001. This European Standard specifies procedures for calculating the creep and/or the fatigue damage of boiler components during operation. These calculations are not required to be carried out by the manufactu
27、rer as part of his responsibilities within this European Standard. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced docu
28、ment (including any amendments) applies. EN 12952-1:2001, Water-tube boilers and auxiliary installations Part 1: General EN 12952-3:2011, Water-tube boilers and auxiliary installations Part 3: Design and calculation for pressure parts 3 Terms and definitions For the purposes of this document, the te
29、rms and definitions given in EN 12952-1:2001 apply. 4 Symbols and abbreviations For the purposes of this document, the symbols and abbreviations given in EN 12952-1:2001, Table 4-1 apply. 5 General The calculations may be carried out, using transposed design equations. The measured (actual) wall thi
30、ckness of the components shall be used in the calculations, i.e. taking into account any wall thickness reduction that may have occurred due to corrosion or erosion during the service life up to the time of the analysis, see EN 12952-3:2011, 5.7. Operating temperature, pressure and especially the ma
31、gnitude of load changes often differ from the estimations used for the design. Thus, these calculations may help to prevent unexpected early failure of components. The results may be used as a guideline for the decision to inspect a component for fatigue cracks or to inspect for creep pores by the r
32、eplica method or any other suitable method. NOTE In some cases, the influence of both creep and fatigue damage will be significant. It is normally conservative to combine the creep and fatigue damage mechanisms by adding the calculated usage factors. If necessary, more detailed methods of assessment
33、 may be used (see 1 PD 7910 Published by British Standardization Institute, London, UK). Thus, the components are not necessarily to be replaced, if the calculated usage factor exceeds the value of 1. The highest loaded components shall be chosen for monitoring purposes. 6 Calculations Annex A descr
34、ibes the creep damage calculation. Annex B describes the fatigue damage calculation. DIN EN 12952-4:2011-10 EN 12952-4:2011 (E) 6 Annex A (informative) Calculation of in-service creep damage A.1 General This annex describes a procedure for calculating the creep damage of a boiler and its major compo
35、nents during operation. It is based on measured values of pressure and temperature, from which the actual primary stress and the expected lifetime at these conditions may be determined. Design lifetime is not necessarily identical with the operating lifetime. It is therefore necessary to make projec
36、tions at various stages throughout the operating lifetime of the boiler to determine its expected lifetime. A.2 Symbols and abbreviations In addition to the symbols given in EN 12952-1:2001, Table 4-1, the symbols given in Table A.1 apply. Table A.1 Symbols Symbol Description Unit fopMembrane stress
37、 at operating conditions N/mm2TopOperated time at operating conditions h TalTime to reach the theoretical rupture by creep h DcCreep damage A.3 Calculation of in-service lifetime and creep damage A.3.1 General The calculation of the usage factor due to creep is a method that retrospectively takes in
38、to consideration the previous modes of operation. It is carried out for highly loaded components on the basis of the measured operating temperatures and gauge pressures. In order to limit the number of the required calculations and to more clearly present the results, the pressure and temperature ra
39、nge over which the component has been operated, shall be broken down into increments. The membrane stress fopat the highest loaded point in the component shall be obtained by transposing the design formula using the mean pressure of each pressure increment. If the operating pressure is not measured
40、continuously during operation the separation into increments is not valid and under such circumstances the operating pressure for 100 % load may be used, thus resulting in more conservative predictions. If available, the measured minimum wall thickness may be used. If this was not measured, the guar
41、anteed minimum wall thickness of the material as delivered shall be used. The theoretical lifetime Talshall be calculated for each rating temperature/pressure. According to Figure A.1, Talis obtained at the intersection of the stress line fopand the lower limit curve of the scatter band of the creep
42、 rupture strength (= 0,8 Rm T tc) at the mean temperature of each temperature increment. The respective portion of the creep damage Dci kfor each incremental temperature/pressure is obtained by the ratio of the operating time Topfor this increment divided by the theoretical lifetime Talfor the same
43、increment. DIN EN 12952-4:2011-10 EN 12952-4:2011 (E) 7 Key a) lg (Rm) b) lg (T), h Figure A.1 Diagram for the determination of TalThe operating times in the temperature/pressure increment shall be summarized, taking into account the temperature allowances for measuring uncertainties and for tempera
44、ture asymmetries in due consideration at this classification. The usage portion for each increment is given by alopkciTTD = (A.1) The creep damage Dcduring the evaluated period shall be obtained from the linear damage rule by summing up the values Dci kfor all temperature increments and, if any, pre
45、ssure as follows: =ikkcicDD (A.2) A.3.2 Online computerized data storage In the case of on-line data storage by means of a data processing system a separation into increments may be waived. For calculation of the theoretical lifetime Talthe on-line measured values of pressure and temperature includi
46、ng the above mentioned allowances shall be used instead of the mean values of the increments. The increase of creep damage is obtained in this case from the measured time divided by the theoretical lifetime (see Tables A.2 and A.3). The computer programme used shall permit the results to be verified
47、 by at least a random test. DIN EN 12952-4:2011-10 EN 12952-4:2011 (E) 8 Table A.2 Summation of data for the calculation of in-service creep damage User and boiler plant: XY Power station: XY Boiler: 3 Works-No.: 12345 Year built: 2003 Maximum allowable pressure HP: 84 bar Reheater: bar Superheated
48、steam temperature: HP: 525 C Reheater: C Steam output: 128 t/h 1 2 3 4 5 6 7 8 9 10 11 12 13 No. Component Material; Steel group a b d mm c esmm ersmm pcbar to Ctc C fapN/mm2Tal 103h 1 HP-line 13CrMo44; 5.1 m AB292,0 o 24,0 21,0 75,5 525 530 48,7 208 2 Superheater 2 header 13CrMo44; 5.1 n AB419,0 o 39,0 39,0 75,5 510 525 56,3 186 3 Superheater 2 outlet line 13CrMo44; 5.1 n AB241,0 o 17,5 17,5 75,5 510 525 48,2 304 4 Superheater 2 outlet hea
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