DIN EN ISO 28723-2011 Vitreous and porcelain enamels - Determination of the edge covering on enamelled steel plate to be used in heat exchangers (ISO 28723 2008) German version EN .pdf

1、June 2011 Translation by DIN-Sprachendienst.English price group 7No 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 25

2、.220.50!$s,a“1800962www.din.deDDIN EN ISO 28723Vitreous and porcelain enamels Determination of the edge covering on enamelled steel plate to be usedin heat exchangers (ISO 28723:2008)English translation of DIN EN ISO 28723:2011-06Emails und Emaillierungen Bestimmung der Kantenabdeckung von emaillier

3、ten Stahlblechen fr Wrmeaustauscher(ISO 28723:2008)Englische bersetzung von DIN EN ISO 28723:2011-06maux vitrifis Dtermination du revtement de larte sur une plaque en acier maill destine auxchangeurs de chaleur (ISO 28723:2008)Traduction anglaise de DIN EN ISO 28723:2011-06SupersedesDIN EN 14863:200

4、6-03www.beuth.deDocument comprises pagesIn case of doubt, the German-language original shall be considered authoritative.1006.11 DIN EN ISO 28723:2011-06 2 A comma is used as the decimal marker. National foreword This standard has been prepared by Technical Committee ISO/TC 107 “Metallic and other i

5、norganic coatings” in collaboration with Technical Committee CEN/TC 262 “Metallic and other inorganic coatings” (Secretariat: BSI, United Kingdom). The responsible German body involved in its preparation was the Normenausschuss Materialprfung (Materials Testing Standards Committee), Working Committe

6、e NA 062-01-63 AA Prfung von Emails und Emaillierungen. ISO 28723 was prepared by the European Committee for Standardization (CEN) as EN 14863 and was adopted as ISO Standard under the “fast-track-procedure” by Technical Committee ISO/TC 107. ISO 28723 published in 2008 was then adopted by CEN/TC 26

7、2 under the “unique acceptance procedure (UAP)” as European Standard EN ISO 28723, replacing EN 14863. The DIN Standard corresponding to the International Standard referred to in this document is as follows: ISO 3696 DIN ISO 3696 Amendments This standard differs from DIN EN 14863:2006-03 as follows:

8、 a) the number of the standard has been changed; b) the standard has been editorially revised. Previous editions DIN EN 14863: 2006-03 National Annex NA (informative) Bibliography DIN ISO 3696, Water for analytical laboratory use Specification and test methods EUROPEAN STANDARD NORME EUROPENNE EUROP

9、ISCHE NORM EN ISO 28723 March 2011 ICS 25.220.50 Supersedes EN 14863:2005English Version Vitreous and porcelain enamels - Determination of the edge covering on enamelled steel plate to be used in heat exchangers (ISO 28723:2008) maux vitrifis - Dtermination du revtement de larte sur une plaque en ac

10、ier maill destine aux changeurs de chaleur (ISO 28723:2008) Emails und Emaillierungen - Bestimmung der Kantenabdeckung von emaillierten Stahlblechen fr Wrmeaustauscher (ISO 28723:2008) This European Standard was approved by CEN on 3 March 2011. CEN members are bound to comply with the CEN/CENELEC In

11、ternal 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 Centre or to a

12、ny 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 the official

13、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, Romania, Slovakia

14、, 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 and by any means reserved worldwide for

15、 CEN national Members. Ref. No. EN ISO 28723:2011: EContents DIN EN ISO 28723:2011-06 EN ISO 28723:2011 (E) 2 Page Foreword3 1 Scope 4 2 Normative references 4 3 Principle4 4 Reagents and materials 4 5 Apparatus .5 6 Test specimens6 7 Procedure .7 8 Calculation and expression of results.7 9 Precisio

16、n.8 10 Test report 8 Foreword The text of ISO 28723:2008 has been prepared by Technical Committee ISO/TC 107 “Metallic and other inorganic coatings” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 28723:2011 by Technical Committee CEN/TC 262 “Metallic an

17、d 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 identical text or by endorsement, at the latest by September 2011, and conflicting national standards shall be withdrawn at the la

18、test by September 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 responsible for identifying any or all such patent rights. This document supersedes EN 14863:2005. According to the CEN/C

19、ENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithu

20、ania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 28723:2008 has been approved by CEN as a EN ISO 28723:2011 without any modification. DIN EN ISO 28723:2011-06 EN ISO 2872

21、3:2011 (E) 3 1 Scope This International Standard specifies a test method for the determination of the covering of the edge of enamelled steel plate to be used in heat exchangers. This method is applicable to all enamelling processes. It is applicable to plates with a thickness between 0,5 mm and 1,5

22、 mm. This method is not applicable where the current flow generated in the test exceeds 3 A. 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 edit

23、ion of the referenced document (including any amendments) applies. ISO 3696, Water for analytical laboratory use Specification and test methods EN 10088-1, Stainless steels List of stainless steels 3 Principle The edge of an enamelled steel plate to be tested is submerged in an electrolyte. An alter

24、nating current source and a stabilized voltage are connected to the plate. The recorded current is a measure of the covering at the edge. 4 Reagents and materials During the analysis, unless otherwise stated, use only reagents of recognized analytical grade and distilled or de-mineralized water or w

25、ater of equivalent purity. 4.1 Pickling fluid, consisting of sulfuric acid (H2SO4) solution, (7 0,5) % by mass, with an Fe2+concentration of (2 1,5) g/l, at a temperature of (60 2) C. 4.2 Test bath electrolyte, consisting of sodium chloride solution, 5 % NaCl by mass, made with distilled water confo

26、rming to grade 3 of ISO 3696, at a temperature of (22 3) C. DIN EN ISO 28723:2011-06 EN ISO 28723:2011 (E) 4 5 Apparatus 5.1 Test bath, consisting of a polypropylene container holding the electrolyte solution in which the electrodes and a test plate are placed. Polypropylene plates are used for cent

27、ring and holding the test plate 10 mm from the bottom of the bath. The arrangement of the bath and the dimensions of the components are shown in Figures 1, 2 and 3. Dimensions in millimetres Key 1 plate to be tested 2 plates for centring and lifting the test plate from the bottom Figure 1 Dimensions

28、 of the test bath Dimensions in millimetres Key 1 electrode (1 264 mm long) 2 NaCl solution Figure 2 Dimensions of the two stainless-steel electrodes (EN 10088-1 grade 1.4301) DIN EN ISO 28723:2011-06 EN ISO 28723:2011 (E) 5 Dimensions in millimetres Figure 3 Dimensions of the two polypropylene cent

29、ring plates 5.2 Voltage source, consisting of a stabilized alternating source of (10,0 0,05) V. The electrical diagram is shown in Figure 4. The voltage source shall be able to maintain these voltage limits throughout the test. Figure 4 Electrical diagram 5.3 Ammeter, capable of reading to the neare

30、st 0,01 A. 6 Test specimens Select at least one pair of plates, one corrugated and one undulated, of the same length. The minimum length of the edge to be used for the test is 300 mm. Immerse the plates in the pickling solution (4.1) in a suitable container for a period of 10 min 10 s. Rinse the pla

31、tes well with water and dry them. DIN EN ISO 28723:2011-06 EN ISO 28723:2011 (E) 6 7 Procedure Using the design drawing, determine, to the nearest 1 mm, the total (i.e. stretched) length of the edge of the corrugated or undulated test specimen. NOTE The stretched edge length is the length taking int

32、o account the profiling of the corrugation and undulation of the test specimen. Determine the un-enamelled thickness of the test specimen to the nearest 0,1 mm. Position the plate in the bath (5.1) in such a way that a maximum of 10 mm of the edge to be measured (one of the edges in the flue gas dir

33、ection) is immersed in the electrolyte solution (4.2). Do this within one hour after rinsing off the sulfuric acid. Connect the voltage source (5.2) between the bath electrodes and electrode L1 to the test specimen and, using the ammeter (5.3), record the current automatically (3 0,5) s after switch

34、ing on the test voltage. Repeat the test for the other edge of the test specimen and for the second test specimen. 8 Calculation and expression of results For each edge, calculate the uncoated surface area, a, in mm2, using the equation: a = 1,222I2+ 12,903I (1) where I is the measured current, in A

35、. Calculate the percentage free surface area, S, using the equation: 100aSbc=(2) where a is the uncoated surface area, in mm2, calculated from Equation (1); b is the stretched length of the edge of the plate, in mm; c is the thickness of the un-enamelled plate, in mm. Calculate the percentage edge c

36、overing, E, using the equation: 100E S= (3) Express the percentage edge covering as the mean of all the determinations, rounded to the nearest 0,1 %. Calculate the uncoated surface area, U, in mm2/m, using the equation: 1000aUb= (4) Express the uncoated surface area per metre length as the mean of a

37、ll the determinations, rounded to the nearest 10 mm2/m. DIN EN ISO 28723:2011-06 EN ISO 28723:2011 (E) 7 9 Precision The precision of this measurement is 0,3 % of the calculated percentage edge covering and 2 mm2/m of the uncoated surface area. 10 Test report The test report shall include the follow

38、ing information: a) all information necessary for the identification of the sample tested; b) a reference to this International Standard, i.e. ISO 28723:2008; c) the results of the test, calculated as described in Clause 8, expressed as: the mean percentage edge covering, rounded to the nearest 0,1

39、%, the mean uncoated surface area per metre length, rounded to the nearest 10 mm2/m, and including the results of the individual determinations and the thickness of the un-enamelled plate. d) any deviations from the procedure specified; e) any unusual features (anomalies) observed during the test; f) the date of the test. DIN EN ISO 28723:2011-06 EN ISO 28723:2011 (E) 8