1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 28721-3:2011Vitreous and porcelain enamels Glass-lined apparatus for process plantsPart 3: Thermal shock resistance (ISO 28721-3:2008)BS EN ISO 28721-3:2011 BRITISH STA
2、NDARDNational forewordThis British Standard is the UK implementation of EN ISO 28721-3:2011. It is identical to ISO 28721-3:2008. It supersedes BS EN 15159-3:2006, which is withdrawn.The UK participation in its preparation was entrusted to T e c h n i c a l C o m m i t t e e S T I / 3 6 , V i t r e
3、o u s e n a m e l c o a t i n g s .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 for its correct application. BSI 2011 ISBN 978 0 580 722
4、83 7 ICS 25.220.50; 71.120.10 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 April 2011.Amendments issued since publicationDate T e x t a f f e c t e dEUROPE
5、AN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 28721-3 April 2011 ICS 25.220.50 Supersedes EN 15159-3:2006English Version Vitreous and porcelain enamels - Glass-lined apparatus for process plants - Part 3: Thermal shock resistance (ISO 28721-3:2008) maux vitrifis - Appareils maills pour les inst
6、allations industrielles - Partie 3: Rsistance au choc thermique (ISO 28721-3:2008) Emails und Emaillierungen - Emaillierte Apparate fr verfahrenstechnische Anlagen - Teil 3: Temperaturschockbestndigkeit (ISO 28721-3:2008) This European Standard was approved by CEN on 17 March 2011. CEN members are b
7、ound 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 obtained on application to the
8、 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-CENELEC Management Centr
9、e 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norwa
10、y, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form a
11、nd by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 28721-3:2011: EBS EN ISO 28721-3:2011 EN ISO 28721-3:2011 (E) 3 Foreword The text of ISO 28721-3:2008 has been prepared by Technical Committee ISO/TC 107 “Metallic and other inorganic coatings” of the International Organiza
12、tion for Standardization (ISO) and has been taken over as EN ISO 28721-3:2011 by Technical Committee CEN/TC 262 “Metallic and other inorganic coatings” the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publication of an identi
13、cal text or by endorsement, at the latest by October 2011, and conflicting national standards shall be withdrawn at the latest by October 2011. 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 r
14、esponsible for identifying any or all such patent rights. This document supersedes EN 15159-3:2006. 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, C
15、yprus, Czech Republic, 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. Endorsement notice The text of ISO
16、 28721-3:2008 has been approved by CEN as a EN ISO 28721-3:2011 without any modification. BS EN ISO 28721-3:2011ISO 28721-3:2008(E) ISO 2008 All rights reserved iiiContents Page Foreword iv 1 Scope . 1 2 Terms and definitions. 1 3 Thermal shock diagram . 2 4 Heating/cooling diagram 4 5 Quality desig
17、nation. 6 Annex A (informative) Explanatory notes 7 Bibliography . 8 BS EN ISO 28721-3:2011ISO 28721-3:2008(E) iv ISO 2008 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of prep
18、aring International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in
19、liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task
20、of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention
21、is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 28721-3 was prepared by the European Committee for Standardization (CEN) (as EN 15159-3) and was adopted, u
22、nder a special “fast-track procedure”, by Technical Committee ISO/TC 107, Metallic and other inorganic coatings, in parallel with its approval by the ISO member bodies. ISO 28721 consists of the following parts, under the general title Vitreous and porcelain enamels Glass-lined apparatus for process
23、 plants: Part 1: Quality requirements for apparatus, components, appliances and accessories Part 2: Designation and specification of resistance to chemical attack and thermal shock Part 3: Thermal shock resistance BS EN ISO 28721-3:2011INTERNATIONAL STANDARD ISO 28721-3:2008(E) ISO 2008 All rights r
24、eserved 1Vitreous and porcelain enamels Glass-lined apparatus for process plants Part 3: Thermal shock resistance 1 Scope This part of ISO 28721 specifies requirements for the thermal shock resistance of, and heating and cooling procedures for, glass-lined apparatus, components, accessories and pipe
25、s primarily used for process equipment in chemical plants. It specifies the limits of thermal shock resistance using diagrams (see Figure 1 and Figure 2). For glass-lined steel, a distinction is made between a thermal shock on the glass-lined side (produced by charging an apparatus) and a thermal sh
26、ock on the steel side (produced by heating or cooling an apparatus). This part of ISO 28721 applies to operating temperatures from 25 C to + 230 C. It is only applicable to enamelled unalloyed and low-alloy carbon steels. 2 Terms and definitions For the purposes of this document, the following terms
27、 and definitions apply. 2.1 glass-lined steel composite material produced by smelting a vitreous and porcelain enamel coat onto a steel substrate 2.2 shock medium substance (e.g. steam, an aqueous liquid or a solid) having a higher or lower temperature than that of the enamel and thus causing a sudd
28、en temperature change when brought into contact with the glass-lined surface 2.3 thermal shock sudden change of temperature, either on the glass-lined side or on the steel side of an enamelled steel item, resulting from contact with a shock medium 2.4 wall temperature TWaverage steel temperature, in
29、 degrees Celsius, of the enamel NOTE The wall temperature is often equivalent to the temperature of the heating or cooling medium entering the jacket of the apparatus. BS EN ISO 28721-3:2011ISO 28721-3:2008(E) 2 ISO 2008 All rights reserved2.5 product temperature TPtemperature, in degrees Celsius, o
30、f the product which is inside the apparatus and in contact with the glass-lined surface or is to be introduced into the apparatus 2.6 temperature of heating or cooling medium THCtemperature, in degrees Celsius, of the medium (e.g. water, steam, heat-transfer oil) which is introduced into the jacket
31、of an apparatus for heating or cooling purposes NOTE Where steam is the heating medium, the temperature of the heating or cooling medium is the condensation temperature at the particular pressure in the jacket of the apparatus. EXAMPLE For saturated steam at an overpressure of 0,6 MPa, THC= 165 C. 3
32、 Thermal shock diagram The thermal shock diagram (see Figure 1) defines the thermal shock limits for a shock medium brought into contact with the glass-lined surface of an apparatus e.g. when a product is introduced into the apparatus and the heating or cooling medium is in a half-pipe coil (or othe
33、r) jacket. These thermal shock limits depend on the wall temperature, TW, and the product temperature, TP. NOTE The values defined in the diagram were calculated assuming essentially infinitely high heat-transfer coefficients which are found to be approximately the case with aqueous shock media. Tab
34、les 1 and 2 give examples showing the corresponding wall temperature and minimum and maximum product temperatures. If the product (e.g. a gas, solid or highly viscous fluid) has a relatively low heat-transfer coefficient, higher thermal shock limits are permitted by agreement with the manufacturer (
35、see Annex A). BS EN ISO 28721-3:2011ISO 28721-3:2008(E) ISO 2008 All rights reserved 3Key X wall temperature, TW(C) Y product temperature, TP(C) Figure 1 Thermal shock diagram for examples 1 to 8 (see Tables 1 and 2) (thermal shock on the glass-lined side of the steel) Table 1 Introducing a hot prod
36、uct into a cold apparatus Wall temperature TWMaximum product temperature TP(rounded) Example C C 1 20 130 2 0 150 3 20 165 4 40 180 BS EN ISO 28721-3:2011ISO 28721-3:2008(E) 4 ISO 2008 All rights reservedTable 2 Introducing a cold product into a hot apparatus Wall temperature TWMinimum product tempe
37、rature TP(rounded) Example C C 5 120 25 6 140 5 7 160 20 8 180 50 4 Heating/cooling diagram The heating/cooling diagram (see Figure 2) defines the thermal shock limits for a shock medium brought into contact with the steel side of the enamelled wall e.g. when a heating or cooling medium is introduce
38、d into the half-pipe coil (or other) jacket of an apparatus filled with a product. These thermal shock limits depend on the temperature of the heating or cooling medium, THC, and of the product, TP. NOTE The values defined in the diagram were calculated assuming essentially infinitely high temperatu
39、re transfer coefficients for both the product and the heating or cooling medium. Such coefficients are found to be approximately the case with aqueous products, with steam used as a heating medium and with water used as a cooling medium. If the product (e.g. a gas, solid or highly viscous fluid) has
40、 a relatively low heat-transfer coefficient, higher thermal shock limits for heating are permitted by agreement with the manufacturer. If relatively low heat-transfer coefficients prevail in the jacket (e.g. if heat-transfer oil is used as the shock medium instead of condensing steam or water), ther
41、mal shock limits wider than those shown in Figure 2 are permitted by agreement with the manufacturer (see Annex A). Tables 3 and 4 give examples showing the corresponding product temperature and maximum heating or minimum cooling temperatures. BS EN ISO 28721-3:2011ISO 28721-3:2008(E) ISO 2008 All r
42、ights reserved 5Key X product temperature, TP(C) Y temperature of heating or cooling medium, THC(C) Figure 2 Diagram for heating and cooling for examples 9 to 16 (see Tables 3 and 4) (thermal shock on the steel side of the enamel) Table 3 Introducing a heating medium into the half-pipe coil (or othe
43、r) jacket of a cold apparatus Product temperature TPMaximum temperature of heating medium THC(rounded) Example C C 9 20 125 10 0 145 11 20 165 12 40 175 BS EN ISO 28721-3:2011ISO 28721-3:2008(E) 6 ISO 2008 All rights reservedTable 4 Introducing a cooling medium into the half-pipe coil (or other) jac
44、ket of a hot apparatus Product temperature TPMinimum temperature of cooling medium THC(rounded) Example C C 13 120 20 14 140 0 15 160 20 16 180 40 If the intended temperature change exceeds the limits in the diagram (see Figure 2), this operation shall be carried out in steps. EXAMPLE Heating a cold
45、 apparatus containing a product at a temperature of 0 C using saturated steam at a temperature of 165 C: First step: Introduce steam at a pressure of 0,3 MPa into the jacket until the product temperature exceeds 25 C. Second step: Switch to steam at a pressure of 0,6 MPa and heat until the product t
46、emperature reaches 165 C. 5 Quality designation Glass-lined steel apparatus, components and pipes conforming to this part of ISO 28721 shall be designated as follows: Resistance to thermal shock in accordance with ISO 28721-3. BS EN ISO 28721-3:2011ISO 28721-3:2008(E) ISO 2008 All rights reserved 7A
47、nnex A (informative) Explanatory notes The thermal shock resistance of a glass-lined apparatus depends on several different factors, such as the physical properties of the enamel, the material characteristics of the steel, the design of the apparatus, the enamelling process used and the service cond
48、itions. The data on thermal shock resistance given in this part of ISO 28721 apply to most glass-lined apparatus in service, based on the following general conditions: a) Apparatus design in accordance with ISO 28721-1; design of flanged pipes and flanged fittings in accordance with DIN 2873 (a perm
49、itted operating pressure from 0,1 MPa to + 0,6 MPa and a permitted operating temperature from 25 C to 230 C inside the apparatus or jacket). b) Base material is unalloyed or low-alloy carbon steel which can be glass-lined with a minimum yield strength of 210 N/mm2. In many cases, this value determines the thermal shock limits for heating and cooling as shown in Figure 2. c) The apparatus and the pipe fittings comply with the quality requirements specified in ISO
