1、April 2011 Translation by DIN-Sprachendienst.English price group 8No 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 7
2、5.120!$nb,“1756309www.din.deDDIN EN ISO 20843Petroleum and related products Determination of pH of fire-resistant fluids within categories HFAE,HFAS and HFC (ISO 20843:2011)English translation of DIN EN ISO 20843:2011-04Minerallerzeugnisse und verwandte Produkte Bestimmung des pH-Wertes schwerentfla
3、mmbarer Flssigkeiten der Kategorien HFAE,HFAS und HFC (ISO 20843:2011)Englische bersetzung von DIN EN ISO 20843:2011-04Ptrole et produits connexes Dtermination du pH des fluides difficilement inflammables de catgories HFAE,HFAS ou HFC (ISO 20843:2011)Traduction anglaise de DIN EN ISO 20843:2011-04Su
4、persedesDIN EN ISO 20843:2004-05www.beuth.deIn case of doubt, the German-language original shall be considered authoritative.Document comprises 9 pages03.11 DIN EN ISO 20843:2011-04 A comma is used as the decimal marker. National foreword This standard has been prepared by Technical Committee ISO/TC
5、 28 “Petroleum products and lubricants” (Secretariat: ANSI, USA) in collaboration with Technical Committee CEN/TC 19 “Gaseous and liquid fuels, lubricants and related products of petroleum, synthetic and biological origin” (Secretariat: NEN, Netherlands). The responsible German body involved in its
6、preparation was the Normenausschuss Materialprfung (Materials Testing Standards Committee), Working Committee NA 062-06-81 AA Spiegelausschuss zu CEN/TC 19 Gasfrmige und flssige Kraft- und Brennstoffe, Schmierstoffe und verwandte Produkte mit minerallstmmiger, synthetischer oder biologischer Herkunf
7、t of the Fachausschuss Minerall- und Brennstoffnormung. The DIN Standards corresponding to the International Standards referred to in this document are as follows: ISO 3170 DIN EN ISO 3170 ISO 3696 DIN ISO 3696 ISO 6743-4 DIN EN ISO 6743-4 Amendments This standard differs from DIN EN ISO 20843:2004-
8、05 as follows: a) normative references have been updated; b) in Subclause 7.2 “Measurement of pH”, possible sources of error have been indicated; c) in Clause 10 “Test report”, information relating to the identification of the product tested has been modified. Previous editions DIN EN ISO 20843: 200
9、4-05 National Annex NA (informative) Bibliography DIN EN ISO 3170, Petroleum liquids Manual sampling DIN EN ISO 6743-4, Lubricants, industrial oils and related products (class L) Classification Part 4: Family H (Hydraulic systems) DIN ISO 3696, Water for analytical laboratory use Specification and t
10、est methods 2 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 20843 January 2011 ICS 75.120 Supersedes EN ISO 20843:2003English Version Petroleum and related products - Determination of pH of fire-resistant fluids within categories HFAE, HFAS and HFCPtrole et produits connexes - Dterminatio
11、n du pH des fluides difficilement inflammables de catgories HFAE, HFAS ou HFC (ISO 20843:2011) Minerallerzeugnisse und verwandte Produkte - Bestimmung des pH-Wertes schwerentflammbarer Flssigkeiten der Kategorien HFAE, HFAS und HFC This European Standard was approved by CEN on 3 January 2011. CEN me
12、mbers 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 obtained on applica
13、tion 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-CENELEC Manag
14、ement 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherl
15、ands, Norway, 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
16、 any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 20843:2011: E(ISO 20843:2011) (ISO 20843:2011) Foreword This document (EN ISO 20843:2011) has been prepared by Technical Committee ISO/TC 28 Petroleum products and lubricants in collaboration with Technical Commi
17、ttee CEN/TC 19 “Gaseous and liquid fuels, lubricants and related products of petroleum, synthetic and biological origin” the secretariat of which is held by NEN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at
18、the latest by July 2011, and conflicting national standards shall be withdrawn at the latest by July 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
19、 such patent rights. This document supersedes EN ISO 20843:2003. 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 Republic, Denmark, Est
20、onia, 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 20843:2011 has been approved by CE
21、N as a EN ISO 20843:2011 without any modification. 2DIN EN ISO 20843:2011-04 EN ISO 20843:2010 (E) “”Introduction HFAE, HFAS and HFC fluids are used in hydraulic systems where the running conditions require fire-resistant fluids. The determination of the pH of aqueous hydraulic fluids is useful to m
22、onitor the product in service. Any important variation can be the sign of bacterial proliferation and can have an impact on the corrosion-protection properties. 3DIN EN ISO 20843:2011-04 EN ISO 20843:2010 (E) WARNING The use of this International Standard may involve hazardous materials, operations
23、and equipment. This International Standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this International Standard to establish appropriate safety and health practices and determine the applicability of regulatory limitation
24、s prior to use. 1 Scope This International Standard specifies a test method to determine the pH value of fire-resistant fluids within categories HFAE, HFAS and HFC, as classified in ISO 6743-4. 2 Normative references The following referenced documents are indispensable for the application of this do
25、cument. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 3170:2004, Petroleum liquids Manual sampling ISO 3696:1987, Water for analytical laboratory use Specification and test methods 3
26、 Principle The pH value is established using a pH meter, which measures the potential difference between two electrodes immersed in the fluid being tested. One of the electrodes should be of glass and the other should be of calomel. NOTE A grouped electrode device can also be used. The pH measuremen
27、t is carried out at 20 C. The measurement should be carried out as soon as possible after sampling, less than 48 h if possible, to avoid errors due to possible oil release and/or pH changing. 4 Reagents and materials 4.1 Water, conforming to Grade 2 of ISO 3696. 4.2 Standard solutions to calibrate t
28、he pH meter. 4.2.1 Buffer solution, pH 7,00 at 20 C. 4DIN EN ISO 20843:2011-04 EN ISO 20843:2010 (E) Dissolve 3,800 g of potassium dihydrogen orthophosphate (KH2PO4) and 3,415 g of disodium hydrogen phosphate (Na2HPO4) in water (4.1) and dilute to 1 000 ml at 20 C. Before use, the potassium dihydrog
29、en orthophosphate shall be dried for 2 h at a temperature between 110 C and 120 C. 4.2.2 Buffer solution, pH 9,22 at 20 C. Dissolve 3,80 g of disodium tetraborate decahydrate (Na2B4O7g15210H2O) in water (4.1) and dilute to 1 000 ml at 20 C. 4.2.3 Buffer solution, pH 11,72 at 20 C. Dissolve 1,42 g of
30、 disodium hydrogen phosphate (Na2HPO4) in a 100 ml solution of carbonate-free sodium hydroxide (NaOH) (0,1 mol/l) and dilute to 1 000 ml at 20 C with water (4.1). NOTE Ready mixed buffer solutions available on the market can be used in place of the buffer solutions listed in 4.2.1 to 4.2.3. It is in
31、tended that the buffer solutions be used within the period indicated on the bottle (in the case of a ready mixed buffer) or within a period of three months after preparation. 4.3 Cleaning reagents 4.3.1 Toluene (C7H8), of analytical quality. 4.3.2 Propan-2-ol (C3H8O), of analytical quality. 5 Appara
32、tus 5.1 pH meter. 5.2 Glass electrode and reference electrode or a grouped electrode device. 5.3 Thermometer, with a range from 0 C to 100 C graduated in 1 C. 5.4 Analytical balance, capable of weighing to the nearest 0,1 mg. 6 Sampling Unless otherwise specified, samples shall be obtained by the pr
33、ocedures described in ISO 3170. 7 Procedure 7.1 Calibration of pH meter Calibrate the pH meter (5.1) at 20 C in accordance with the manufacturers instructions, preferably using the buffer solutions specified in 4.2. The pH value of these solutions should lie on either side of the expected pH value o
34、f the fluid being tested. 7.2 Measurement of pH The pH measurement should be carried out as soon as possible after sampling (see Clause 6), less than 48 h if possible, to avoid errors due to possible oil release and/or pH changing. 5DIN EN ISO 20843:2011-04 EN ISO 20843:2010 (E) 6DIN EN ISO 20843:20
35、11-04 EN ISO 20843:2010 (E) Pour the fluid being tested into a glass beaker and adjust to a temperature of 20 C g114 1 C. Carefully clean the electrodes in water (4.1), immerse them in the fluid under test, and read off the pH value from the meter (5.1) after a stabilization time of approximately 1
36、min. If there is an oil separation on the surface of the fluid, avoid any oil deposit on the measuring part of the glass electrode which could modify the contact potential and give rise to measurement errors. After the test, clean the electrodes with toluene (4.3.1) followed by propan-2-ol (4.3.2).
37、8 Expression of results Report the pH value to the nearest 0,1 unit of pH. 9 Precision 9.1 General The precision of this test method has been estimated. 9.2 Repeatability, r The difference between two test results obtained by the same operator with the same apparatus under constant operating conditi
38、ons on identical test material would, in the long run, in the normal and correct operation of the test method, exceed the following value in only one case in twenty. HFAE, HFAS and HFC fluids, r g32 0,2 9.3 Reproducibility, R The difference between two single and independent test results obtained by
39、 different operators working in different laboratories on identical test material would, in the long run, in the normal and correct operation of the test method, exceed the following value in only one case in twenty. HFAE and HFAS fluids: R g32 0,6 HFC fluids: R g32 0,3 10 Test report The test repor
40、t shall contain at least the following information: a) a reference to this International Standard, i.e. ISO 20843:2010; b) the type and complete identification of the product tested, including, for HFAE and HFAS fluids, the water type and percentage of concentrate used to make up the fluid; c) the r
41、esult of the test (see Clause 8); d) any deviation, by agreement or otherwise, from the procedures specified; e) the date of the test. fying o il or concentrate used to make up the fluid should also be indicated. N1) National footnote: F or H FA fl uids, th e p ercentage o f e mulsiN1)Bibliography 1 ISO 6743-4, Lubricants, industrial oils and related products (class L) Classification Part 4: Family H (Hydraulic systems) 7DIN EN ISO 20843:2011-04 EN ISO 20843:2010 (E)
