1、I CEmi1 h 3YOY589 0012b97 8 T EUROPEAN STANDARD EN 278:1991 NORME EUROPEENNE EUROPAISCHE NORM May 1991 unc 6:9.4:6zo.i:52-416:541.534.06 Descriptors: Household appliances, gas appliances, membranec;, rubber products, specifications, characteristics, tests English version Rubber materials for diaphra
2、gms in domestic appliances using combustible gases up to 200 mbar Matriaux base de caoutchouc pour Elastomer-Werkstoffe fr Membranen jr membranes destines aux appareils domestiques utilisant les combustibles 200 mbar Gazeux jusqui ?O0 mbar Haushaltsgerten fr Brenngase bis This E?iropean Standard was
3、 approved by CEN on 1991-05-06 CEN members are Sound to comply with the CEN/CENELEC internal Regulations which stipulate the conditions for giving this European Standard tile status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationa
4、l standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, Gernian). A version in any other language made by translation under the responsibility of a CEN member into its own language and noti
5、fied to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and IJnited Kingd
6、om. CEN European Committee for Standardization Comite Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, 8-1050 Brussels (c) CEN 1991 Copyright reserved to all CEN members F -_- II_ _- Ref. ?(o. EN 278:1991 E I CEN ENu278 91 m 3404589 0012b98 T W Page 2
7、EN 278:1991 Contents list Foreword Introduction 1 2 Normative References 3 Definitions 4 Classification of material 5 Requirements 6 Methods of test Scope and Field of Application Page 3 4 5 5 6 6 6 a e . CEN EN*278 91 3404589 0012699 II Page 3 EN 278:1991 FOREWORD This document drawn up by MARCOGAZ
8、, AFECI, AEGPL and AFECGAZ Liaison Committee CL 13 “Lubricant and Sealing Materials“. European Standard was prepared by CEN/TC 108 on the basis of a In accordance with the Common CEN/CENELEX Rules, the following countries are bound to implement this European Standard : Austria, Belgium, Denmark, Fin
9、land, France, Germany, Greece, Ireland, Island, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden,Switzerland and United Kingdom. CEN ENa278 91 W 3404589 0012700 4 W Page 4 EN 278:1991 Introduction This standard defines the quality of materials to be used for the manufacture of diaphra
10、gms, It specifies tests to be carried out on specified samples taken from sheet and fixes the test values to be met. It may be necessary to carry out supplementary tests on the diaphragms themselves: - Tests on diaphragms mounted in the appliance. These are intended to confirm the functional suitabi
11、lity of the diaphragms and should be performed under the most severe service conditions envisaged in the appropriate standards. - Tests on the diaphragm itself. These are intended to confirm that the material from which the dia- phragm is manufactured is one that complies with this standard. The fac
12、t that most diaphragms are small in size does not in general, allow for the necessary standard samples to be prepared for the tests from them. The test methods shall be chosen from those specified in this standard but the test values will possibly be different due to the dimensional differences of t
13、he sample. This can also be especially applicable to diaphragms manufactured from fabric reinforced materials. In the case of reinforced diaphragms, the gas resistance, and lubricant resistance tests should be carried out on ltfinichedtt material: no delamination should occur. Page 5 EN 278:1991 CEN
14、 EN*278 91 W 3404589 O012701 b - r- .- 1 Scope and Field of Application This European standard specifies requirements and tests for rubber materials for diaphragms used in domestic gas appliances of all categories, and auxiliary equipment mounted on or intended to be mounted on such appliances, in c
15、ontact with combustible gases, up to 200 mbar This standard deals with materials from which are manufactured diaphragms of two kinds: - Homogeneous - Reinforced The normal range of envisaged operating temperatures covered by this standard is O “C to 60 “C. Temperatures outside this range may be prop
16、osed by the manufacturer with limits between -20 “C and + 80 “C. 2 Normative references IS0 37: 1977 Rubber, vulcanized - Determination of tensile stress-strain properties; IS0 48: 1979 Vulcanized rubbers - Determination of hardness (Hardness between 30 and 85 IHRD); IS0 188: 1982 Rubber, vulcanized
17、 - Accelerated ageing or heat- resistance tests; IS0 815: 1972 Vulcanized rubbers - Determination of compression set under constant deflection at normal and high temperatures; IS0 1431/1: 1989 Rubber, vulcanized or thermoplastic - Resistance to ozone cracking -Part 1 - Static strain test IS0 1653: 1
18、975 Vulcanized rubbers - Determination of compression set under constant deflection at low temperatures IS0 1817: 1985 Rubber vulcanized - Determination of the effect of liquids IS0 4648: 1978 Rubber, vulcanized - Determination of dimensions of test pieces and products for test purposes, CEN ENr278
19、93 = 3404589 0032702 8 = I Page 6 EN 278:1991 Range of hardness (IRHD) 3 3 1. 3.2 4 5 5.1 5.2 r , 35 to 40 41 to 55 56 to 75 Dfinitions For the purposes of this standard the following definitions apply Diaphragm: Thin membrane of rubber, located in a fixture and serving as a flexible gas tight parti
20、tion between two chambers, Reinforcement: Woven or unwoven textile, arranged in or on the rubber diaphragm material, thus reinforcing certain of the properties of such a diaphragm, for example the bursting strength. Classification of materials There are three classes (1, 2 and 3) which are defined b
21、y the range of hardness in accordance with table 1. Table 1 - Clascification by hardness I1 I * l3 1 Class The class and temperature range shall beindicated by the diaphragm material manufacturer. He shall also indicate if the diaphragm material is or is not resistant: to ozone, Requirements Visual
22、proDerty The material shall be free from porosity, inclusions, blisters and surface imperfections visible to the naked eye, Phvsical and chemical DroDerties The material shall be in accordance with the requirements laid down in table 2. - - CEN EN*Z78 91 E 3404589 0012703 T W Page 7 EN 278:1991 Tabl
23、e 2 - Requirements for material Property Hardness1) Tolerances on the values given by the supplier Tensile strength Elongation at break Compression set2) - at low temperature - at standard temperature +23 “C - at high temperature Resistance to ageing - change in hardness - change in tensile strenght
24、h - change in elongation at break Resistance to gas - change of mass after immersior - change of mass after drying Resistance to lubricants - change in volume - change in hardness Resistance to ozone3) Unit IRHD IRHD MPa % % % % IRHD % % % % % IRHD 1 35 to 40 +5 25 2 500 I 40 I 20 s 35 +_8 2 -15 2 -
25、25 -10 to +10 -15 to + 5 -10 to +15 1: 10 no cracks Class 2 41 to 55 +5 27 2 300 5 40 I 20 5 25 +8 2 -15 2 -25 - 5 to +10 -10 to + 5 -10 to +15 k 10 no cracks 3 56 to- 75 25 1 10 1 200 5 40 I 20 I 25 k8 2 -15 2 -25 -5 to +10 -8 to + 5 -10 to +l! k 10 no cracks 1) The hardness of the material shall b
26、e stated by the manufacturer. 2) The sample shall not be damaged by adhering to the surfaces. 3) Requirement for this test will be limited to material declared ozone resistant by the manufacturer. Due to the potential interruption of any surface, such as waxes, by the operation of the diaphragm such
27、 protective methods shall not be used without some additional protective additive. I CEN EN*278 91 3404589 0012704 1 Page 8 EN 278:1991 6 Methods of test In addition to the conditions below reference should be made to table 3. Test pieces shall be cut from a sheet of material (2 i- al2) mm or (6,3 k
28、 0,3) mm thickness according to the test. Measurement of thickness shall be carried out according to IS0 4648. The material shall be from the same compound formulation used to make the components, and vulcanized under conditions which are comparable to those used in production. 6.2 FJagdneSs Test th
29、e hardness in accordance with one of the methods specified in IS0 48, in the event of a disagreement the micro-test shall be used. Five measurements shall be carried out on each sample. Test the tensile strength and elongation at fracture with the method specified in IS0 37 and the following special
30、 conditions: Six dumb-bell test pieces, type 2 is preferred, In the event of a disagreement, type 2 shall be used. 6.4.1 Test at high temperature and standard temperature Test the compression set at high temperature in accordance with the method specified in IS0 815 using three small test pieces. Pl
31、ace the loaded compression apparatus during (72 2) h at (23 k 2)“C respectively (24 ) h in an oven at (70 +_ 1)“C. For envisaged operating temperatures above the normal limit of 60 OC, the test shall be carried out at: 10 “C above the upper limit. O O -0,5 6.4.2 Test at low temerature Test the compr
32、ession set at low temperature in accordance with the method specified in IS0 1653 using three small tes pieces. Place the loaded compression apparatus during (72 ) h in a low temperature cabinet at (-5 k 1)OC. 6 -2 For envisaged operating temperatures below the normal limit of O OC, the test shall b
33、e carried out at 5 “C below the lower limit, CEN EN*Z78 91 - 3Y04589 0012705 3 Page 9 EN 278ii991 Test the resistance to ageing in accordance with the method specified in IS0 188 in a normal oven using six dumb-bell testpieces, type 2 (see 6.3) and three separate test pieces for the hardness test (s
34、ee 6.2). Place the test pieces in the oven during (168 o ) h at (70 k 1) OC. -2 If the envisaged operating temperature is above the normal limit of 60 “CI the test shall be carried out at 10 “C above the upper limit, Test the resistance to gas in accordance with IS0 1817:1985 specifically 8.2, and t
35、he following special conditions: Use three test pieces each of 50 mm x 20 mm X 2 mm weighed. Immerse for (72 O ) h at (23 1: 2) “C in n-pentane (98 % min. -2 normal pentane by mass, estimated by gas chromatography). After removal from the liquid, dry rapidly and weigh immediately. Determine the chan
36、ge in mass with reference to the initial mass of Dry for a period of (168 2) h in an oven at (40 & 1) OC at O - the sample. atmospheric pressure. Determine by weighing the new change in mass with reference to the initial mass of the sample. For the calculation, the arithmetic mean value of the three
37、 results both after immersion and after drying to be used. Test the resistance to lubricants in accordance with IS0 1817:1985 ttvolumetric method“ (8.2) and “hardness test“ (11.2) and the following special conditions: Three test pieces each of 50 mm x 20 mm x 2 m. .- CEN EN*Z78 91 W 3q04.589 O032706
38、 5 Page 10 EN 278:1991 O Duration of immersion to be (168+* ) h in oil nr. 2 at the maximum envisaged working temperature of (60 k 1) “C or upper declared limit if greater. Determine the change in volume and the change in hardness. Test the resistance to ozone in accordance with IS0 1431/1 “Method A
39、“ and the following special conditions: Duration of the test : (24_0,5) O h. Concentration of ozone (50 k 5) pphm by volume ). Test temperature : (30 k 2) OC. Relative humidity : I65 %. Elongation of sample : (20 k 2) %. pphm = parts per hundred millions Page 11 EN 278:1991 Use the arthmetic mean va
40、lue both after inmersion and drying Detankno the increase in volume and th. change in hardness Table 3 - Test: methods ?roperty iardness lensile strength and %longation at break :ompression set - at low temperature - at 23 C - at high temperature Resistance to ageing - hardness - tensile strength an
41、d elongation at break Sas resistance - immersion in n-pentant - drying Lubricant roiirtuico - Lmnersion in olnr.2 Resistance to ozone XSO 48 37 1653 815 815 188 48 37 1817 QWe 1817 Q 0 sause and 11.2) 1431/1 Method A lest pieces ryp. dumb-bell type 2 small type small type small type 50x202) mn 50x20
42、2) m umber Test emperaturo (Cl 23 i 2 23 f 2 t2(+10 I 1) t2(+ 10 i 1) 23 f 2 23 f 2 23 f 2 40 I 2 t2 i 1 30 f 2 Dur a ti on of test (h) O -2 72 O -2 72 O 24 0,5 O -2 168 O -2 72 O -2 168 O 168-2 O -0,5 24 iicro-hardness test is nandatory for reference purposes tl lower limit of operating temperature
43、 indicated by th manufacturer, Final measurement after (30 i 3) min at low temperature at the end of the exposure period t2 upper limit of operating temperature indicated by th- manufacturer Standard normal oven Weigh and determine change in mass. Elongation of sample (20 I 2) 1 concentration of ozone (5015) pphm
