1、BRITISH STANDARD BS EN ISO 8316:1997 BS 6199-2:1988 renumbered, incorporating Amendment No. 1 Measurement of liquid flow in closed conduits Method by collection of the liquid in a volumetric tank The European Standard EN ISO 8316:1995 has the status of a British StandardBSEN ISO 8316:1997 This Briti
2、sh Standard, having been prepared under the directionof the Industrial-process Measurement and Control Standards Committee, was published under the authority ofthe Board of BSI and comes intoeffect on 30 September1988 BSI 07-1999 The following BSI references relate to the work on this standard: Comm
3、ittee reference PCL/2 Draft for comment 84/24918 DC ISBN 0 580 16766 6 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the industrial-process Measurement and Control Standards Committee (PCL/-) to Technical Committee PCL/2, upon which the fo
4、llowing bodies were represented: British Compressed Air Society British Gas plc. Department of Energy (Gas and Oil Measurement Branch) Department of Trade and Industry (National Engineering Laboratory) Department of Trade and Industry (National Weights and Measures Laboratory) Electricity Supply Ind
5、ustry in England and Wales Energy Industries Council GAMBICA (BEAMA Ltd.) Institute of Measurement and Control Institute of Trading Standards Administration Institution of Gas Engineers Institution of Mechanical Engineers Water Authorities Association The following bodies were also represented in th
6、e drafting of the standard, through subcommittees and panels: Society of British Gas Industries University of Surrey Amendments issued since publication Amd. No. Date of issue Comments 9339 January 1997 Indicated by a sideline in the marginBSEN ISO 8316:1997 BSI 07-1999 i Contents Page Committees re
7、sponsible Inside front cover National foreword ii Foreword 2 1 Scope and field of application 3 2 References 3 3 Symbols and definitions 3 4 Principle 4 5 Apparatus 8 6 Procedure 11 7 Calculation of flow-rate 12 8 Calculation of the overall uncertainty in the flow-rate measurement 13 Annex A Correct
8、ions to the measurement of filling time 18 Annex B Density of pure water at standard atmospheric pressure of101,325kPa 22 Annex C Example of a volumetric flow-rate installation using the dynamic gauging method 22 Annex D Example of a volumetric flow-rate installation using the standing start and fin
9、ish method 23 Annex E Students t-distribution 25 Annex ZA (normative) Normative references to international publications with their relevant European publications 26 Figure 1 Schematic diagram of a volumetric flow-rate installation using the static gauging method 6 Figure 2 Schematic diagram of a vo
10、lumetric flow-rate installation using the dynamic gauging method 7 Figure 3 Examples of diverter design 9 Figure 4 Operating law of diverter 10 Figure 5 Twin tanks method 12 Figure 6 Typical graph used in evaluation of (e R ) pfor a diverter system 15 Figure 7 Graph with plotting of results of diver
11、ter time actuator tests, as given inA.1.2 20 Figure 8 Graph of the filling process for the measuring tank 20 Figure 9 Diagram of system for measuring the switching time and switching time difference of the diverter 21 Figure 10 Graph of volume collected against time at constant flow-rate 21 Figure 1
12、1 Schematic diagram of a volumetric installation using the standing start and finish method 23 Figure 12 Design of volumetric tank 24 Figure 13 Diagram of the flow-rate of liquid entering the tank 25 Table 1 3 Table 2 22 Table 3 26 List of references Inside back coverBSEN ISO 8316:1997 ii BSI 07-199
13、9 National foreword This British Standard has been prepared by Technical Committee CPL/30 (formerly PCL/2). It is identical with ISO8316:1987 “Measurement of liquid flow in closed conduits Method by collection of the liquid in a volumetric tank”, published by the International Organization for Stand
14、ardization (ISO). In 1995 the European Committee for Standardization (CEN) accepted ISO8316:1987 as European Standard ENISO8316:1995. As a consequence of implementing the European Standard this British Standard is renumbered as BSENISO8316 and any reference to BS6199-2:1988 should be read as a refer
15、ence to BSENISO8316. Terminology and conventions. The text of the international standard has been approved as suitable for publication as a British Standard without deviation. Some terminology and certain conventions are not identical with those used in British Standards; attention is drawn especial
16、ly to the following. Wherever the words “International Standard” appear, referring to this standard, they should be read as “Part of BS6199”. The comma has been used as a decimal marker. In British Standards it is current practice to use a full point on the baseline as a decimal marker. At present t
17、here is no corresponding British Standard for ISO4373. The Technical Committee has reviewed the provisions of ISO4373 and has decided that they are acceptable for use in conjunction with this standard. ISO 4185, although listed in clause2, is not referred to in the text. A British Standard does not
18、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. Cross-references International standard Corresponding British Standar
19、d ISO 4006:1977 BS 5875:1980 Glossary of terms and symbols for measurement of fluid flow in closed conduits (Identical) ISO 5168:1978 BS 5844:1980 Methods of measurement of fluid flow: estimation of uncertainty of a flow-rate measurement (Identical) Summary of pages This document comprises a front c
20、over, an inside front cover, pages i and ii, theEN ISO title page, pages 2 to 26, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STAN
21、DARD NORME EUROPENNE EUROPISCHE NORM EN ISO 8316 September 1995 ICS 17.120.10 Descriptors: Liquid flow, pipe flow, flow measurements, volume measurements, tanks containers, gauging, flow rate, flowmeters, error analysis English version Measurement of liquid flow in closed conduits Method by collecti
22、on of the liquid in a volumetric tank (ISO 8316:1987) Mesure de dbit des liquides dans les conduites fermes Mthode par jaugeage dun rservoir volumtrique (ISO 8316:1987) Durchflumessung von Flssigkeiten in geschlossenen Leitungen Verfahren der Volumenbestimmung mit einem Mebehlter (ISO 8316:1987) Thi
23、s European Standard was approved by CEN on1995-08-31. 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 c
24、oncerning such national 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, German). A version in any other language made by translation under the responsibility of a CEN member into its
25、own language and notified 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, Switzerl
26、and and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1995 All rights of reproduction and communication in any form and by any means reserved in all countries to CEN an
27、d its members Ref. No. EN ISO 8316:1995 EEN ISO 8316:1995 BSI 07-1999 2 Foreword This European Standard was taken over by CEN from the work of ISO/TC30, Measurement of fluid flow in closed conduits, of the International Standards Organization (ISO). This European Standard shall be given the status o
28、f a national standard, either by publication of an identical text or by endorsement, at the latest by March 1996, and conflicting national standards shall be withdrawn at the latest by March1996. According to the CEN/CENELEC Internal Regulations, the following countries are bound to implement this E
29、uropean Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, United Kingdom.EN ISO 8316:1995 BSI 07-1999 3 1 Scope and field of application This International Standard specifies methods
30、for the measurement of liquid flow in closed conduits by determining the volume of liquid collected in a volumetric tank in a known time interval. It deals in particular with the measuring apparatus, the procedure, the method for calculating the flow-rate and the assessment of uncertainties associat
31、ed with the measurements. The method described may be applied to any liquid provided that a) its vapour pressure is sufficiently low to ensure that any escape of liquid by vaporization from the volumetric tank does not affect the required measurement accuracy; b) its viscosity is sufficiently low so
32、 as not to alter or delay unduly the measurement of the level in the volumetric tank; c) it is non-toxic and non-corrosive. Theoretically, there is no limit to the application of this method, but, for practical reasons, this method of measurement is normally used for flow-rates less than approximate
33、ly1,5m 3 /s and is used on the whole in fixed laboratory installations only. However, there is a variation of this method which uses a natural or artificial storage pond as a volumetric tank, but this application is not dealt with in this International Standard. Owing to its high potential accuracy,
34、 this method is often used as a primary method for calibrating other methods or devices for volume flow-rate measurement or for mass flow-rate measurement; for the latter method or device, it is necessary to know the density of the liquid accurately. If the installation for flow-rate measurement by
35、the volumetric method is used for purposes of legal metrology, it shall be certified and registered by the national metrology service. Such installations are then subject to periodic inspection at stated intervals. If a national metrology service does not exist, a certified record of the basic measu
36、rement standards (length, time and temperature), and error analysis in accordance with this International Standard and ISO5168, shall also constitute certification for legal metrology purposes. Annex A forms an integral part of this International Standard. Annex B to Annex E, however, are given for
37、information only. 2 References ISO 4006, Measurement of fluid flow in closed conduits Vocabulary and symbols. ISO 4185, Measurement of liquid flow in closed conduits Weighing method. ISO 4373, Measurement of liquid flow in open channels Water level measuring devices. ISO 5168, Measurement of fluid f
38、low Estimation of uncertainty of a flow-rate measurement. 3 Symbols and definitions 3.1 Symbols (see also ISO 4006) Table 1 Symbol Quantity Dimensions SI unit e R Random uncertainty, in absolute terms a a E R Random uncertainty, as a percentage e S Systematic uncertainty, in absolute terms a a E S S
39、ystematic uncertainty, as a percentage q m Mass flow-rate MT 1 kg/s q V Volume flow-rate L 3 T 1 m 3 /s t Filling time of the tank T s V Discharged or measured volume L 3 m 3 z Liquid level in the tank L m A Density M 3 kg/m 3 a The dimensions and units are those of the quantities in question.EN ISO
40、 8316:1995 4 BSI 07-1999 3.2 Definitions For the purposes of this International Standard, the definitions given in ISO4006 apply. Only terms which are used with a particular meaning or the meaning of which might be usefully restated are defined below. The definitions of some of the terms concerned w
41、ith error analysis are given in ISO5168. 3.2.1 static gauging a method by which the net volume of liquid collected is deduced from measurements of liquid levels (i.e.gaugings), made respectively before and after the liquid has been diverted for a measured time interval into the gauging tank, to dete
42、rmine the volume contained in the tank 3.2.2 dynamic gauging a method by which the net volume of liquid collected is deduced from gaugings made while liquid flow is being delivered into the gauging tank. (A diverter is not required with this method.) 3.2.3 diverter a device which diverts the flow ei
43、ther to the gauging tank or to its by-pass without changing the flow-rate during the measurement interval 3.2.4 flow stabilizer a device inserted into the measuring system, ensuring a stable flow-rate in the conduit being supplied with liquid; for example, a constant level head tank, the level of li
44、quid in which is controlled by a weir of adequate length 4 Principle 4.1 Statement of the principle 4.1.1 Static gauging method The principle of the flow-rate measurement method by volumetric static gauging (seeFigure 1 for a schematic diagram of a typical installation) is to determine the initial v
45、olume of liquid contained in the tank; to divert the flow into the volumetric tank, until it is considered to contain a sufficient quantity to attain the desired accuracy, by operation of a diverter which actuates a timer to measure the filling time; to determine the final volume of liquid contained
46、 in the tank. The volume contained at the initial and at the final times is obtained by reading the liquid levels in the tank and by reference to a preliminary calibration which gives the level-volume relationship. The flow-rate is then derived from the volume of liquid collected and the filling tim
47、e as explained in clause7. One variation of this method uses two tanks which are successively filled (see6.3). A further variation, given inAnnex D, uses a valve instead of a diverter mechanism to start and stop the flow into a volumetric tank. Care shall be taken when using a valve instead of a div
48、erter that the flow-rate does not change when the valve is operated. 4.1.2 Dynamic gauging method The principle of the flow-rate measurement method by volumetric dynamic gauging (seeFigure 2 for a schematic diagram of a typical installation) is to let liquid collect in the tank to a predetermined in
49、itial level (and thus volume), at which time the timer is started; to stop the timer when a second predetermined final level (and thus volume) is reached and then to drain the liquid collected. The flow-rate is then derived as explained in clause7.EN ISO 8316:1995 BSI 07-1999 5 4.1.3 Comparison of instantaneous and mean flow-rates It should be emphasized that only the mean value of flow-rate for the filling period is given by the volumetric method. Instantaneous values of flow-rate as obtained on a
