1、DRAFT FOR DEVELOPMENT DD IEC TS 60695-11-40: 2002 Fire hazard testing Part 11-40: Test flames Confirmatory tests Guidance ICS 13.220.40; 29.020 DD IEC TS 60695-11-40:2002 This Draft for Development, was published under the authority of the Standards Policy and Strategy Committee on 17 January 2002 B
2、SI 17 January 2003 ISBN 0 580 41120 6 National foreword This Draft for Development reproduces verbatim IEC TS 60695-11-40:2002 This publication is not to be regarded as a British Standard. It is being issued in the Draft for Development series of publications and is of a provisional nature because i
3、t is a research report and not a full standard as it provides background information only, supporting development of test flame standards. It should be applied on this provisional basis, so that information and experience of its practical application may be obtained. Comments arising from the use of
4、 this Draft for Development are requested so that UK experience can be reported to the international organization responsible for the Technical Specification. A review of this publication will be initiated not later than 3 years after its publication by the international organization so that a decis
5、ion can be taken on its status at the end of its 3-year life. Notification of the start of the review period will be made in an announcement in the appropriate issue of Update Standards. According to the replies received by the end of the review period, the responsible BSI Committee will decide whet
6、her to support the conversion into an international standard, to extend the life of the Technical Specification for another 3 years or to withdraw it. Comments should be sent in writing to the Secretary of BSI Technical Committee GEL/89, Fire hazard testing, at British Standards House, 389 Chiswick
7、High Road, London W4 4AL, giving the document reference and clause number and proposing, where possible, an appropriate revision of the text. A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement inte
8、rnational publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. Summary of pages This document comprises
9、a front cover, an inside front cover, the IEC TS title page, pages 2 to 18, 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. Date CommentsSPCIFICATION TECHNIQUE CEI IEC T
10、ECHNICAL SPECIFICATION TS 60695-11-40 Premire dition First edition 2002-02 Essais relatifs aux risques du feu Partie 11-40: Flammes dessai Essais de confirmation Guide Fire hazard testing Part 11-40: Test flames Confirmatory tests Guidance Numro de rfrence Reference number CEI/IEC/TS 60695-11-40:200
11、2 PUBLICATION FONDAMENTALE DE SCURIT BASIC SAFETY PUBLICATION DDIECTS606951140:2002TS 60659-11-04 IEC:0202 2 2 CONTENTS FOREWORD.3 INTRODUCTION.5 1 Scope.6 2 Normative references .6 3 Definitions 6 4 Test flames, burner types and dynamics.7 4.1 General dynamics .7 4.2 Diffusion flames and burners.7
12、4.3 Pre-mixed flames and burners.7 4.4 Fuel gases 8 5 Confirmatory test hardware 8 5.1 General .8 5.2 Procedure and hardware arrangement.8 5.3 Thermocouple .8 5.4 Copper block material .8 5.5 Copper block mass9 5.6 Copper block geometry9 5.7 Copper block positioning .9 6 Confirmatory test procedure
13、.9 6.1 Test temperature ranges .9 6.2 Test time ranges .9 7 Copper block calorimetry dynamics and theory.9 8 Calorimetry and theory Summary and recommendations12 9 Conclusion .12 Bibliography18 Figure 1 Positioning of the copper block 13 Figure 2 Results using data from table 214 Figure 3 Parabolic
14、fit of data to 800 C 15 Figure 4 Parabolic fit of data to 900 C 16 Figure 5 Parabolic fit of data to 1 000 C17 DDIECTS606951140:20022TS 60659-11-04 IEC:0202 3 3 INTERNATIONAL ELECTROTECHNICAL COMMISSION _ FIRE HAZARD TESTING Part 11-40: Test flames Confirmatory tests Guidance FOREWORD 1) The IEC (In
15、ternational Electrotechnical Commission) is a worldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote international co-operation on all questions concerning standardization in the electrical and ele
16、ctronic fields. To this end and in addition to other activities, the IEC publishes International Standards. Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental an
17、d non-governmental organizations liaising with the IEC also participate in this preparation. The IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2) The formal decisions or agre
18、ements of the IEC on technical matters express, as nearly as possible, an international consensus of opinion on the relevant subjects since each technical committee has representation from all interested National Committees. 3) The documents produced have the form of recommendations for internationa
19、l use and are published in the form of standards, technical specifications, technical reports or guides and they are accepted by the National Committees in that sense. 4) In order to promote international unification, IEC National Committees undertake to apply IEC International Standards transparent
20、ly to the maximum extent possible in their national and regional standards. Any divergence between the IEC Standard and the corresponding national or regional standard shall be clearly indicated in the latter. 5) The IEC provides no marking procedure to indicate its approval and cannot be rendered r
21、esponsible for any equipment declared to be in conformity with one of its standards. 6) Attention is drawn to the possibility that some of the elements of this technical specification may be the subject of patent rights. The IEC shall not be held responsible for identifying any or all such patent ri
22、ghts. The main task of IEC technical committees is to prepare International Standards. In exceptional circumstances, a technical committee may propose the publication of a technical specification when the required support cannot be obtained for the publication of an International Standard, despite r
23、epeated efforts, or The subject is still under technical development or where, for any other reason, there is the future but no immediate possibility of an agreement on an International Standard. Technical specifications are subject to review within three years of publication to decide whether they
24、can be transformed into International Standards. This first edition of IEC 60695-11-40, which is a technical specification, has been prepared by IEC technical committee 89: Fire hazard testing. It has the status of a basic safety publication in accordance with IEC Guide 104. DDIECTS606951140:20023TS
25、 60659-11-04 IEC:0202 4 4 The text of this technical specification is based on the following documents: Enquiry draft Report on voting 89/468/DTS 89/494/RVC Full information on the voting for the approval of this technical specification can be found in the report on voting indicated in the above tab
26、le. This publication has been drafted in accordance with the ISO/IEC Directives, Part 3. The committee has decided that the contents of this publication will remain unchanged until 2006. At this date, the publication will be reconfirmed; withdrawn; replaced by a revised edition, or amended. DDIECTS6
27、06951140:20024TS 60659-11-04 IEC:0202 5 5 INTRODUCTION Small-scale, standard flames (see note) are specified for various tests, where sufficient hardware design and use parameters are specified in an effort to ensure consistent flames. Hardware designs and dimensions, material specifications and fue
28、l and air specifications are typical necessary parameters. Experience has shown that the quality of the resulting flames and, therefore, the associated test results, are influenced significantly by subtle variations in the equipment and test technique. Some simple checks on flame qualities, such as
29、flame colour and dimensions, or the melting characteristics of silver wire, are often specified in conjunction with hardware, fuel, air or other normal adjustments. The need for more precise and quantitative confirmation of flame qualities has been recognized, leading to the introduction of confirma
30、tory tests based on the copper block calorimetry technique. This technical specification is intended to provide guidance for the design of test flame confirmatory tests using copper block calorimetry measurements. Table 1 Existing test flames with confirmatory tests Nominal flame power Flame type a
31、Reference IEC 60695- Approximate overall height Approximate cone height Copper block mass Copper block position above burner Time spec. 100 C to 700 C Wm m m m g m m s 1 000 PP-P 2-4/1 (11-2) 175 55 10 95 45 500 M-P 11-3 125 40 10 55 54 50 M-P 11-4 20 1,76 10 44 Needle B-D 2-2 (11-5) 12 0,58 6 23,5
32、aPP propane; M methane; B butane; P pre-mixed; D diffusion NOTE Flame power and height generally less than 2 000 W and 200 mm, respectively. NOTE Readers are encouraged to send test data to the TC 89 Secretary for further study by the author and as valuable feedback for the next revision. The coordi
33、nates of the secretary can be found on the IEC website http:/www.iec.ch DDIECTS606951140:20025TS 60659-11-04 IEC:0202 6 6 FIRE HAZARD TESTING Part 11-40: Test flames Confirmatory tests Guidance 1 Scope This part of IEC 60695 presents a general characterization of small-scale test flames and associat
34、ed confirmatory tests based on copper block calorimetry, and defines theoretical modelling for the associated dynamics. Guidance is presented for the selection of critical parameters in confirmatory test designs. A theory is presented to define additional performance parameters for confirmatory test
35、s, enabling a precise implicit mathematical characterization of confirmatory test heating curves. One of the responsibilities of a technical committee is, wherever applicable, to make use of basic safety publications in the preparation of its publications. 2 Normative references The following refere
36、nced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC Guide 104:1997, The preparation of safety publications and the us
37、e of basic safety publications and group safety publications ISO/IEC 13943:2000, Fire safety Vocabulary 3 Definitions For the purpose of this part of IEC 60695, definitions taken from ISO/IEC 13943, together with the following definitions, apply. 3.1 copper block heat content theoretical total avail
38、able thermal energy attributable only to the copper test block temperature, copper heat capacity and mass 3.2 confirmatory test calorimetric procedure intended as a diagnostic indicator to reveal anomalous behaviour or conditions in a test flame, burner or associated hardware 3.3 flame stabilizer as
39、sembly normally fitted to the top of a standard laboratory Bunsen or Tirrill burner intended to mitigate the destabilizing effect of the turbulent mixing of flame gases with the ambient air, by providing an intervening layer of gas having an intermediate velocity between the ambient still air and th
40、e faster flame gases DDIECTS606951140:20026TS 60659-11-04 IEC:0202 7 7 4 Test flames, burner types and dynamics 4.1 General dynamics Flames consist of chemically exothermic reacting gaseous mixtures of oxidizer (typically oxygen or air mixture) and reducer or fuel (typically fuel gas or vapour). For
41、 standardized test flames, suitable hardware with supplies of combustible materials deliver a continuous flow of the needed gaseous reactants to maintain the desired standardized flame. 4.2 Diffusion flames and burners Diffusion flames are produced by a simple flow of fuel gases that combust at the
42、point of mixing with air at the exit orifice of the hardware. The advantages of diffusion flames are the simplicity of the hardware (often a simple tube), and the better simulation of actual flames likely to be encountered in equipment. The disadvantage is that they are geometrically less stable. 4.
43、3 Pre-mixed flames and burners Pre-mixed flames are produced by mixing a part of the combustion air with the fuel gas prior to the combustion point at the end of the burner tube. The remaining part of the combustion air is provided in a similar way as with diffusion flames. The resulting flame has a
44、n inner/lower cone that is typically a lighter blue colour consisting of the pre-mixed gas and air mixture with excess fuel gas, and an outer/upper cone that is typically a very faint darker blue colour where the remaining needed additional air diffuses into this upper portion of the flame. The inne
45、r/lower cone is at a much lower temperature and is chemically reducing, while the outer/upper part of the flame is much hotter and more oxidizing. Flame stabilizer assemblies are sometimes added around the exit orifice to enhance flame stability and prevent the flame from leaving the top of the burn
46、er by providing a layer of pre- mixed gases with a reduced velocity interfaced between the main high velocity central flow and the surrounding still air, thus moderating the velocity gradient between the main central flow and the still air. Gases enter the stabilized flame through metering holes in
47、the upper end of the burner tube. Pre-mixed flames have the advantage of higher efficiency and higher flame temperature, and allow the metering of combustion air as well as fuel gas, but require much more complex hardware than used to produce diffusion flames. The combustion air in pre- mixed burner
48、s can be either directly metered or provided through an adjustable open shutter assembly using the Venturi effect. 4.3.1 Metered air pre-mixed burners These designs provide for the control of metered air and fuel gas. Both can be introduced through specified orifices with specified flow rates and ba
49、ck pressures. Normally, an extra manifold assembly is used for the metered air and the restrictive fuel gas orifice is still necessary to produce a high gas stream flow rate for proper mixing. Having both metered air as well as fuel gas will provide much better control of the resulting standardized flames. 4.3.2 Venturi air pre-mixed burners In these traditional designs
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