BS-EN-13787-2001.pdf

BRITISH STANDARD BS EN 13787:2001 Elastomers for gas pressure regulators and associated safety devices for inlet pressures up to 100 bar The European Standard EN 13787:2001 has the status of a British Standard ICS 23.040.80 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 05:03:24 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 13787:2001 This British Standard, having been prepared under the direction of the Engineering Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 30 November 2001 © BSI 30 November 2001 ISBN 0 580 36790 8 National foreword This British Standard is the official English language version of EN 13787:2001. The UK participation in its preparation was entrusted to Technical Committee GSE/32, Gas governors, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 10, an inside back cover and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. DateComments Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 05:03:24 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM EN 13787 October 2001 ICS 83.060; 83.140.50 English version Elastomers for gas pressure regulators and associated safety devices for inlet pressures up to 100 bar Elastomères pour régulateurs de pression de gaz et dispositifs de sécurité associés pour pressions amont jusqu'à 100 bar Elastomere für Gas-Druckregelgeräte und zugehörige Sicherheitseinrichtungen für Eingangsdrücke bis 100 bar This European Standard was approved by CEN on 15 September 2000. CEN members 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 application to the 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 Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels © 2001 CENAll rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 13787:2001 E Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 05:03:24 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13787:2001 (E) 2 Contents Page Foreword3 1Scope 4 2Normative references 4 3Terms and definitions4 4Characteristics.5 4.1General requirements5 4.2Additional characteristics.6 5Test methods for general requirements7 5.1General conditions of testing.7 5.2Hardness.7 5.3Tensile strength and elongation at break7 5.4Compression set7 5.5Resistance to ageing.7 5.6Resistance to gas 7 5.7Resistance to lubricants .7 Annex A (informative) Additional characteristics8 A.1General8 A.2Resistance to ozone 8 A.3Resistance to abrasion8 A.4Resistance to tear8 Annex B (normative) Special national conditions .9 B.1Special national conditions 9 B.2Special national condition for Sweden9 Bibliography10 Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 05:03:24 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13787:2001 (E) 3 Foreword This European Standard has been prepared by Technical Committee CEN/TC 235 “Gas pressure regulators and associated safety devices for use in gas transmission and distribution“, the secretariat of which is held by UNI. 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 April 2002, and conflicting national standards shall be withdrawn at the latest by April 2002. This European Standard includes one informative annex (Annex A) and one normative annex (Annex B related to a special national condition for Sweden). According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 05:03:24 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13787:2001 (E) 4 1 Scope This European Standard specifies the minimum requirements for elastomeric materials intended to be used as static seals, dynamic seals or diaphragms in the gas pressure regulators covered by EN 334 and in the safety devices for gas pressure regulating stations and installations covered by the corresponding European Standards, as well as the relevant test methods to assess these requirements. This European Standard applies to elastomeric materials for use with gases of the first and second gas families to EN 437, for inlet pressures less than or equal to 100 bar, and in an operating temperature range between 10 °C, (or 20 °C when applicable), and +60 °C. This European Standard also gives some additional characteristics and recommendations for their application likely to be requested for elastomers in the order specifications, and the corresponding test methods (see informative Annex A). This European Standard only applies for type testing. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). EN 334, Gas pressure regulators for inlet pressures up to 100 bar. EN 437, Test gases Test pressures Appliance categories. EN 549, Rubber materials for seals and diaphragms for gas appliances and gas equipment. ISO 37, Rubber vulcanized or thermoplastic Determination of tensile stress-strain properties. ISO 48, Rubber, vulcanized or thermoplastic Determination of hardness (hardness between 10 IRHD and 100 IRHD). ISO 188, Rubber, vulcanized or thermoplastic Accelerated ageing and heat resistance tests. ISO 815, Rubber, vulcanized or thermoplastic Determination of compression set at ambient, elevated or low temperatures. ISO 1817, Rubber, vulcanized Determination of the effect of liquids. 3 Terms and definitions For the purposes of this European Standard, the following definitions apply: 3.1 static seal component which ensures a seal between two parts of a gas pressure regulator or parts of its associated safety devices which do not have relative movement (O rings, sheet gaskets, etc.) NOTE Adapted from EN 549. Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 05:03:24 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13787:2001 (E) 5 3.2 dynamic seal component which ensures a seal between two parts of a gas pressure regulator or parts of its associated safety devices which have relative movement (lip seals, some O rings) NOTE Adapted from EN 549. 3.3 diaphragms 3.3.1 diaphragm membrane of rubber material located in a fixture and serving as a flexible gas tight partition between two chambers EN 549 3.3.2 main diaphragm diaphragm, the function of which is to detect the feedback of the controlled variable and/or the diaphragm which provides the thrust to move the control member EN 334 3.3.3 control member movable part of the regulator which is positioned in the flow path to restrict the flow through the regulator. A control member may be a plug, ball, disk, vane, gate, diaphragm, etc. EN 334 3.4 seat ring part assembled in a component of the regulator to provide a removable soft seat EN 334 4 Characteristics 4.1 General requirements Elastomeric materials used for non reinforced diaphragms and static and dynamic seals, shall conform to the required values and tolerances given in Table 1. Test methods are detailed in clause 5. All materials shall be free from porosity, inclusion, blisters and surface imperfections visible to the naked eye. Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 05:03:24 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13787:2001 (E) 6 Table 1 Requirements of elastomers for seals and diaphragms PropertyUnitsHardness Class 5060708090 Hardness Tolerances on stated nominal hardness IRHD? 5? 5? 5? 5+3 / 5 Tensile strength, minimumMPa6991010 Elongation at break, minimum%40030020015080 Compression set a - at 70 °C, after 24 h - where applicable, at 10 °C after 24 h or at 20 °C after 24 h % % 25 40 50 25 40 50 25 40 50 25 40 50 25 40 50 Resistance to ageing - Change in hardness - Change in tensile strength - Change in elongation at break IRHD % % ? 10 ? 15 +10 / 25 ? 10 ? 15 +10 / 25 ? 10 ? 15 +10 / 25 ? 8 ? 15 +10 / 25 ? 6 ? 15 +10 / 25 Resistance to gas (n-pentane) - Change in mass after immersion (72 h, 23 °C) - Change in mass after drying (168 h, 40 °C), maximum % % +10 / 5 +5 / 10 +10 / 5 +5 / 10 +10 / 5 +5 / 10 +10 / 5 +5 / 8 +10 / 5 +5 / 8 Resistance to lubricants Oil IRM 902, 168 h at 70 °C - Change in hardness - Change in mass IRHD % ? 10 +15 / 10 ? 10 +15 / 10 ? 10 +15 / 10 ? 10 +15 / 10 ? 10 +15 / 10 a When the diaphragm has a function of detection, this test is not applicable (see 4.2.2). Materials used for reinforced diaphragms should meet the requirements of Table 1. Moreover, specific additional tests may be necessary. 4.2 Additional characteristics 4.2.1The requirements given in 4.1 are intended for general use, however, for some applications, particularly with regard to the design of the regulator or the safety device, and according to the provisions of the order specification, additional characteristics may be asked for. For testing these additional characteristics, the test methods given in informative Annex A should be used, taking into account test conditions and assessment criteria set up in the order specification. For such additional characteristics, the 4.2.2 to 4.2.4 should be considered. 4.2.2For parts in contact with the atmosphere, under normal conditions of use, elastomers resistant to ozone should be used. In particular, this characteristic should be taken into account when the diaphragm has a function of detection. 4.2.3Where the diaphragm is used as a sensing system, compression set is not considered to be relevant and should be replaced by a type test in the regulator standard EN 334 or in the appropriate EN standard for safety devices, as applicable. 4.2.4For seat rings the values are the same as in Table 1, but additional tests such as tear strength and abrasion could be introduced as quoted in informative Annex A. Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 05:03:24 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13787:2001 (E) 7 5 Test methods for general requirements 5.1 General conditions of testing Unless otherwise specified, tests are carried out at a temperature of (23 ± 2) °C. 5.2 Hardness The hardness is measured by IRHD, preferably according to the micro-test method specified in ISO 48. 5.3 Tensile strength and elongation at break Tensile strength and elongation at break are measured according to ISO 37 and expressed in MPa and percentage respectively. The test is performed preferably on dumb bell test pieces of type 2. 5.4 Compression set Tests are carried out according to ISO 815 (type B test piece) under the following conditions: ? at high temperature: after 24 h at 70 °C; ? at low temperature: after 24 h at 10 °C or 20 °C. 5.5 Resistance to ageing Changes in hardness, tensile strength, elongation at break are measured to 5.2 and 5.3 respectively after ageing in accordance to ISO 188, at a temperature of 70 °C for 168 h (7 days). 5.6 Resistance to gas Resistance to gas is measured in percentage of change in mass after immersion in n-pentane (72 0 2? ) h at (23 ? 2) °C, and after drying (168 0 2? ) h at 40 °C, according to the test method given in ISO 1817. 5.7 Resistance to lubricants Resistance to lubricants is measured according to the test method given in ISO 1817, under the following specific conditions: ? immersion during (168 0 2? ) h in oil IRM 902 at 70 °C; ? changes in mass and hardness are determined with reference to the initial mass and hardness of the samples. Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 05:03:24 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13787:2001 (E) 8 Annex A (informative) Additional characteristics A.1 General In order to meet some special provisions of the order specifications, in particular for specific applications as stated in 4.2, elastomer materials should have additional specific characteristics of resistance to ozone, resistance to abrasion or resistance to tear. The corresponding limit values and particular test conditions, if applicable, are defined in the order specifications. Unless otherwise specified, the test methods given in A.2 to A.4 should be applied. A.2 Resistance to ozone Where applicable, resistance to ozone is measured according the test method given in ISO 1431-1, with the following test criteria: ? ozone concentration: (25 ? 5) pphm ? temperature: (40 ? 2) °C ? e