1、BRITISH STANDARD BS EN 279:1991 Specification for Homogenous rubber materials for dynamic seals in domestic appliances using combustible gases up to200 mbar This European Standard EN279:1991 has the status of a British StandardBSEN279:1991 This British Standard was published under the authority ofth
2、e Standards Board and comesinto effect on 29November1991 BSI 09-1999 The following BSI references relate to the work on this standard: Committee reference GSE/22 Draft for comment 88/74022 DC ISBN 0 580 19964 9 Cooperating organizations The European Committee for Standardization, under whose supervi
3、sion this European Standard was prepared, comprises the national standards organizations of the following Western European countries. Austria Oesterreichisches Normungsinstitut Belgium Institut belge de normalisation Denmark Dansk Standardiseringsraad Finland Suomen Standardisoimisliito, r.y. France
4、 Association franaise de normalisation Germany Deutsches Institut fr Normung e.V. Greece Hellenic Organization for Standardization Iceland Technological Institute of Iceland Ireland National Standards Authority of Ireland Italy Ente Nazionale Italiano di Unificazione Luxembourg Inspection du Travail
5、 et des Mines Netherlands Nederlands Normalisatie-instituut Norway Norges Standardiseringsforbund Portugal Instituto Portugus da Qualidade Spain Asociacin Espaola de Normalizacin y Certificacin Sweden Standardiseringskommissionen i Sverige Switzerland Association suisse de normalisation United Kingd
6、om British Standards Institution Amendments issued since publication Amd. No. Date CommentsBSEN279:1991 BSI 09-1999 i Contents Page Cooperating organizations Inside front cover National foreword ii Foreword 2 Text of EN 279 3 National appendix NA Inside back cover National appendix NB Inside back co
7、verBSEN279:1991 ii BSI 09-1999 National foreword This British Standard has been prepared under the direction of the Gas Standards Policy Committee and is the English language version of EN279 “Homogenous rubber materials for dynamic seals in domestic appliances using combustible gases up to 200 mbar
8、” published by the European Committee for Standardization (CEN). EN279 was produced as a result of international discussion in which the UK took an active part. National appendix NA gives the constitution of the committees for UK participation in the preparation of this standard. National appendix N
9、B gives details of International Standards quoted in this standard for which there is an identical or technically equivalent British Standard. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct appli
10、cation. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN title page, pages 2 to 6, an inside back cover and a back cover. This standard has been updated (
11、see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 279 May 1991 UDC 678.4:620.1:62-762.444:641.534.06 Incorporates Corrigendum September 1991 Descriptors: Household
12、 appliances, gas appliances, seals: stoppers, rubber products, classifications, specifications, characteristics, tests English version Homogenous rubber materials for dynamic seals in domestic appliances using combustible gases up to 200 mbar Matriaux base de caoutchouc homognes pour joints dynamiqu
13、es dtanchit destins aux appareils domestiques utilisant les combustibles gazeux jusqu 200 mbar Homogene Elastomer-Werkstoffe fr dynamische Dichtungen in Haushaltsgerten fr Brenngase bis 200 mbar This European Standard was approved by CEN on6May1991. CEN members are bound to comply with the CEN/CENEL
14、EC 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 Central Secretariat or to any CE
15、N 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 Central Secretariat has the same status as the official versions. CEN m
16、embers are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europi
17、sches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels CEN 1991 Copyright reserved to all CEN members Ref. No. EN 279:1991 EEN279:1991 BSI 09-1999 2 Foreword This European Standard was prepared by CEN/TC108 on the basis of a document drawn up by MARCOGAZ, AFECI, AEGPL and
18、AFECOGAZ Liaison Committee CL 13 “Lubricant and Sealing Materials”. In accordance with the Common CEN/CENELEC Rules, the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, N
19、orway, Portugal, Spain, Sweden, Switzerland and United Kingdom. Contents Page Foreword 2 Introduction 3 1 Scope and field of application 3 2 Normative references 3 3 Definition of dynamic seal 3 4 Classification of materials 3 5 Requirements 3 6 Methods of test 3 Table 1 Classification of material 4
20、 Table 2 Requirements for material 4 Table 3 Test methods 6EN279:1991 BSI 09-1999 3 Introduction This standard defines the quality of materials to be used for the manufacture of seals. It specifies tests to be carried out on specified samples taken from sheet and fixes the test values to be met. It
21、may be necessary to carry out supplementary tests on the seals themselves. Tests on seals mounted in the appliance. These tests are intended to confirm the functional suitability of the seal and should be performed under the most severe service conditions envisaged in the appropriate standards. Test
22、s on the seal itself. These tests are intended to confirm that the material from which the seal is manufactured is one that complies with this standard. The fact that most seals are small in size does not, in general, allow for the necessary standard samples for the tests to be prepared from them. T
23、he test methods should be chosen from those specified in this standard but the test values will possibly be different due to the dimensional differences of the sample. 1 Scope and field of application This European standard specifies requirements and tests for homogeneous rubbers for dynamic seals u
24、sed in domestic gas appliances of all categories, and in auxiliary equipment mounted or intended to be mounted on such appliances, in contact with combustible gases up to200mbar. This standard deals with materials from which are manufactured dynamic seals, such as: “O” rings and lip seals; valve par
25、ts. NOTERubber materials for use in diaphragms are considered in EN278. 2 Normative references EN 278:1991, Rubber materials for diaphragms in domestic appliances using combustible gases up to200mbar. ISO 37:1977, Rubber, vulcanized Determination of tensile stress-strain properties. ISO 48:1979, Vul
26、canized rubbers Determination of hardness. ISO 188:1982, Rubber, vulcanized Accelerated ageing or heat-resistance tests. ISO 815:1972, Vulcanized rubbers Determination of compression set under constant deflection at normal and high temperatures. ISO 1653:1975, Vulcanized rubbers Determination of com
27、pression set under constant deflection at low temperatures. ISO 1817:1985, Rubber, vulcanized Determination of the effect of liquids. ISO 4648:1978, Rubber, vulcanized Determination of dimensions of test pieces and products for test purposes. 3 Definition of dynamic seal In this standard a dynamic s
28、eal is a component that ensures a seal between two components which have relative movement. 4 Classification of materials The rubber materials are divided into groups and classes. 4.1 There are two groups (1 and 2), which are defined by their physical and chemical characteristics (seeTable 2). 4.2 T
29、here are five classes (A up to E) which are defined by the ranges of envisaged operating temperatures and which determine the test temperature of the stated material. They are detailed inTable 1. The group and class of the material shall be indicated by the material manufacturer. 5 Requirements 5.1
30、Visual quality The material shall be homogeneous, free from porosity, inclusions, blisters and surface imperfections visible to the naked eye, even after cutting. 5.2 Physical and chemical properties The material shall be in accordance with the requirements laid down inTable 2. 6 Methods of test In
31、addition to the conditions below reference should be made toTable 3. 6.1 General conditions Test pieces shall be cut from a sheet of material() mm or (6,3 0,3)mm thickness according to the test. Measurement of thickness shall be carried out according to ISO4648. The material shall be from the same c
32、ompound formulation used to make the seals, vulcanized under conditions which are comparable to those used in production. 2 + 0,2 0EN279:1991 4 BSI 09-1999 6.2 Hardness Test the hardness in accordance with one of the methods specified in ISO48; in the event of a disagreement the micro-test shall be
33、used. Five measurements shall be carried out on each sample. 6.3 Tensile strength and elongation at break Test the tensile strength and elongation at break with the method specified in ISO37 using the following conditions: six dumb-bell test pieces, type2 is preferred. In the event of a disagreement
34、, type2 shall be used. 6.4 Compression set 6.4.1 Test at high temperature Test the compression set at high temperature in accordance with the method specified in ISO815 using3 small test pieces. Place the loaded compression apparatus in an oven for a duration of (168 ) h at a temperature related to
35、the class of the material. 6.4.2 Test at low temperature Test the compression set at low temperature in accordance with the method specified in ISO1653 using3 small test pieces. Table 1 Classification of material Table 2 Requirements for material 0 2 Group 1 1 1 1;2 1;2 Class A B C D E Working tempe
36、rature C 0 to 60 0 to 80 0 to 100 0 to 125 0 to 150 Property Unit Group 1 Group 2 Hardness atolerances hardness 40 to 75 hardness 76 to 84 hardness 85 to 91 IRHD IRHD IRHD 5 4 3 5 4 3 Tensile strength MPa U 7 U 5 Elongation at break % U 125 U 125 Compression set at high temperature bat low temperatu
37、re % % k40 k40 k40 k40 Resistance to ageing change in hardness, max. change in tensile strength, max. change in elongation at break, max. IRHD % % 10 40 40 10 40 40 Gas resistance change in mass after immersion, max. change in mass after drying, max. % % + 10 5 + 5 8 no requirement c 5 Lubricant res
38、istance change in hardness, max. change in volume, max. IRHD % 10 + 15 10 15 + 10 10 a The hardness of the material shall be stated by the manufacturer of the seal. b The sample shall not be damaged by adhering to the surfaces of the test apparatus. c The swelling after immersion in liquid n-pentane
39、 by some group 2 materials may be substantial.EN279:1991 BSI 09-1999 5 Place the loaded compression apparatus in a low temperature cabinet for a duration of (72 ) h at( 5 1) C. 6.5 Resistance to ageing Test the accelerated ageing in accordance with the method specified in ISO188 in a normal oven usi
40、ng6 dumb-bell test pieces group2 (see6.3) and3 separate test pieces for the hardness test (see6.2. Place the test pieces in the oven for a duration of (168 ) h at a temperature related to the class of the material. 6.6 Resistance to gas Test the resistance to gas in accordance with ISO1817:1985 clau
41、se 8.2, and the following conditions. Using three weighed test pieces each of dimensions50mm 20mm 2mm. Immerse all three samples for (72 ) h at(23 2) C in n-pentane (98% min. n-pentane by mass, estimated by gas chromatography). After removal from the liquid, dry rapidly by wiping and immediately wei
42、gh. Determine the change in mass with reference to the initial mass of the sample. Dry for a period of (168 ) h in an oven at(40 1) C at atmospheric pressure. Determine the new change in mass with reference to the initial mass of the sample by weighing. For the calculation the arithmetic mean value
43、of the three results both after immersion and after drying is to be used. 6.7 Resistance to lubricants Test the resistance to lubricants in accordance with ISO1817:1985 Volumetric method (8.2) and Hardness test (11.2) and the following special conditions. Use three test pieces each50mm 20mm 2mm. Dur
44、ation of immersion to be (168 )h in oil no. 2 with maximum envisaged working temperature corresponding to the material classification according toTable 1. Determine the increase in volume and the change in hardness. 0 2 0 2 0 2 0 2 0 2EN279:1991 6 BSI 09-1999 Table 3 Test methods Property ISO Test p
45、ieces Test temperature ( C) Duration of test (h) Remarks Type Number Hardness 48 3 23 2 Micro-hardness test is mandatory for reference purposes Tensile strength and elongation at break 37 dump-bell type 2 6 23 2 Compression set at high temperature 815 small type disc 13,5 0,5 mm 6,3 0,3 mm thickness
46、 3 class A: 70 1 B: 100 1 C: 125 2 D: 150 2 E: 175 2 at low temperature 1653 small type disc 13,0 0,5 mm 6,3 0,3 mm thickness 3 5 1 Final measurement after (30 3) min at( 5 1) C at the end of the exposure period Resistance to ageing hardness tensile strength and elongation at break 188 48 37 dump-be
47、ll type 2 3 6 class A: 70 1 B: 100 1 C: 125 2 D: 150 2 E: 175 2 Normal oven Gas resistance immersion in n-pentane 1817 (clause 8.2) (50 20 2) mm 3 23 2 Weigh and determine change in mass. Use the arithmetic mean value, both after immersion and drying drying 40 2 Lubricant resistance 1817 (clause 8.2
48、 and 11.2) (50 20 2) mm 3 class A: 50 1 B: 80 1 C: 100 1 D: 125 2 E: 150 2 Determine the increase in volume and the change in hardness immersion in oil no. 2 168 0 2 72 0 2 168 0 2 72 0 2 168 0 2 168 0 2BSEN279:1991 BSI 09-1999 National appendix NA The United Kingdom participation in the preparation
49、 of this European Standard was entrusted by the Gas Standards Policy Committee (GSE/-) to Technical Committee GSE/22 upon which the following bodies were represented: Association of Control Manufacturers (TACMA, BEAMA Ltd.) British Combustion Equipment Manufacturers Association British Gas plc Chief and Assistant Chief Fire Officers Association Department of Trade and Industry (Consum
