1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 1267:2012Industrial valves Test of flowresistance using water as testfluidBS EN 1267:2012 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of
2、 EN 1267:2012. Itsupersedes BS EN 1267:1999 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee PSE/18/1, Industrial valves, steam traps, actuators andsafety devices against excessive pressure - Valves - Basic standards.A list of organizations represented o
3、n this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2012ISBN 978 0 580 67641 3ICS 23.060.01Compliance with a British Sta
4、ndard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 January 2012.Amendments issued since publicationDate Text affectedBS EN 1267:2012EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 1267 Ja
5、nuary 2012 ICS 23.060.01 Supersedes EN 1267:1999English Version Industrial valves - Test of flow resistance using water as test fluid Robinetterie industrielle - Essai de rsistance lcoulement utilisant leau comme fluide dessai Industriearmaturen - Messung des Strmungswiderstandes mit Wasser als Prfm
6、edium This European Standard was approved by CEN on 26 November 2011. 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 bibliographi
7、cal references concerning such national standards may be obtained on application to the CEN-CENELEC 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
8、 of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hun
9、gary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Managem
10、ent Centre: Avenue Marnix 17, B-1000 Brussels 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 1267:2012: EBS EN 1267:2012EN 1267:2012 (E) 2 Contents Page Foreword 41 Scope 52 Normative references 53 Terms and definitions .54 T
11、est facility .64.1 General 64.2 Test tube lengths .84.3 Test tube sizes .84.3.1 Steel test tubes 84.3.2 Copper test tubes 94.4 Pressure tappings94.5 Measurement devices 104.6 Test fluid 105 Test procedure 105.1 Test conditions . 105.1.1 Permissible measurement fluctuations 105.1.2 Steady conditions
12、. 115.1.3 Permissible non-steady conditions 115.2 Pressure loss in test tubes 115.3 Valve test . 126 Calculation . 136.1 Valve pressure loss determination . 136.2 Coefficient calculations . 146.2.1 Flow resistance coefficient (zeta). 146.2.2 Flow coefficient, Kv. 146.2.3 Flow coefficient, Cv. 146.3
13、Uncertainty 156.3.1 Total measurement uncertainty 156.3.2 Flow coefficients, Kvand Cv. 156.3.3 Pressure loss coefficient, (zeta) . 167 Test report . 16Annex A (informative) Lower limit considerations . 18Annex B (informative) Flow rate and physical phenomena of flow through a valve . 19B.1 General .
14、 19B.2 Normal flow conditions 20B.3 Cavitation . 21B.4 Flashing (self-vaporizations) . 21Annex C (informative) Uncertainty on measurement . 22C.1 Introduction . 22C.2 Permissible measurement fluctuations 22C.2.1 General . 22C.2.2 Direct visual observation of signals delivered by the systems . 22C.2.
15、3 Automatic recording of signals delivered by measurement systems . 23C.2.4 Automatic integration of signals delivered by the measurement systems 24C.3 Measured value stability on physical quantities . 25C.4 Determining flow rate and pressure loss coefficients in turbulent rating condition . 26Annex
16、 D (informative) Evaluation of uncertainty of flow rate coefficient (Kv) and pressure losses coefficient () . 27D.1 Generality 27D.2 Evaluation of measurement uncertainty of the Kv(Cv) 27BS EN 1267:2012EN 1267:2012 (E) 3 D.2.1 Determination of flow rate coefficient . 27D.2.2 Identification of uncert
17、ainty of input quantities . 28D.2.3 Sensitivity coefficient 28D.2.4 Type A evaluation uncertainty . 29D.2.5 Expression of relative uncertainty . 29D.3 Evaluation of measurement uncertainty of the . 30D.3.1 Determination of flow resistance coefficient 30D.3.2 Identification of uncertainty of input qu
18、antities . 30D.3.3 Sensitivity coefficient 30D.3.4 Type A evaluation uncertainty . 32D.4 Expression of relative uncertainty on 32Bibliography 33BS EN 1267:2012EN 1267:2012 (E) 4 Foreword This document (EN 1267:2012) has been prepared by Technical Committee CEN/TC 69 “Industrial valves”, the secretar
19、iat of which is held by AFNOR. 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 July 2012, and conflicting national standards shall be withdrawn at the latest by July 2012. Attention is drawn to th
20、e possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 1267:1999. The main changes compared to the previous edition are the following: a)
21、 the scope was specified and editorially revised; b) the normative references were updated; c) Clause 3 on terms and definitions was revised; d) Clause 4 on test facility was changed; e) Clause 5 on test procedure was changed; f) Annex A on lower limit considerations was revised; g) Annex D on evalu
22、ation of uncertainty of flow rate coefficient (Kv) and pressure losses coefficient () was added; h) a bibliography was added. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Bel
23、gium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
24、BS EN 1267:2012EN 1267:2012 (E) 5 1 Scope This European Standard specifies a method for determining valve pressure loss coefficient and fluid flow coefficient using water as test fluid. This method is suitable for valves with low zeta values but higher than 0,1 by determining pressure loss, with res
25、pect to fluid flow rate and specific gravity, and for valves with equal inlet and outlet nominal size. Industrial process control valves are excluded from this European Standard. NOTE 1 For zeta values above 6, the pressure loss coefficient inaccuracy is higher than the pressure loss caused by the t
26、est tubes. It becomes the same configuration of tests as in EN 60534-2-3. NOTE 2 If using air as test fluid, other standards e.g. EN 60534-2-3 and ISO 6358 should be referred to. 2 Normative references The following referenced documents are indispensable for the application of this document. For dat
27、ed references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 736-1:1995, Valves Terminology Part 1: Definition of types of valves EN 736-3:2008, Valves Terminology Part 3: Definition of terms EN 1057, Copp
28、er and copper alloys Seamless, round copper tubes for water and gas in sanitary and heating applications EN 24006:1993, Measurement of fluid flow in closed conduits Vocabulary and symbols (ISO 4006:1991) EN ISO 6708:1995, Pipework components Definition and selection of DN (nominal size) (ISO 6708:19
29、95) ISO 7-1:1994, Pipe threads where pressure-tight joints are made on the threads Part 1: Dimensions, tolerances and designation ISO 7194:2008, Measurement of fluid flow in closed conduits Velocity-area methods of flow measurement in swirling or asymmetric flow conditions in circular ducts by means
30、 of current-meters or Pitot static tubes 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 flow coefficient Kvor CvEN 736-3:2008, 3.4.1 BS EN 1267:2012EN 1267:2012 (E) 6 3.2 flow resistance coefficient EN 736-3:2008, 3.4.5 3.3 fluctuations low
31、period modifications of the measured value of a physical quantity around its mean value during the measurement reading time 3.4 nominal diameter DN EN ISO 6708:1995, 2.1 3.5 stability stability, or the permanent rating conditions, which is reached, when the variations or value changes for these same
32、 physical quantities are low enough between a given reading and the next one 3.6 types of valves EN 736-1:1995 3.7 uncertainty EN 24006:1993, 5.26 4 Test facility 4.1 General A basic flow test facility is shown in Figure 1. The position of components outside the frame may be determined by the labora
33、tory. For angle valves (Figure 1 b), the tested valve and the tube section (L3length) may be laid either vertically or horizontally. For multi-way valves, additional test tubes of the same type shall be used, in the same conditions. BS EN 1267:2012EN 1267:2012 (E) 7 NOTE L1and L3 10 D and L2and L4 2
34、 D. a) Straight valves b) Angle or multiport valves Key 1 water supply 6 upstream pressure measuring device 2 flow meter 7 valve under test 3 temperature measurement 8 downstream pressure tapping point 4 regulating valve 9 regulating valve 5 upstream pressure tapping point 10 differential pressure m
35、easuring device Figure 1 Test installation BS EN 1267:2012EN 1267:2012 (E) 8 4.2 Test tube lengths The test tube lengths and the pressure measurement point positions shall comply with Figure 1. Lengths are measured from test tube ends. If the test facility includes two elbows in series in different
36、planes upstream, a link L1greater than 10 D, shall be adopted unless straightener is installed before the upstream test tube. If a flow straightener is used, length L1may be smaller than 10 D, provided that the conditions in 5.1 are met. For other details concerning flow straighteners, refer to ISO
37、7194:2008, Clause 6. 4.3 Test tube sizes 4.3.1 Steel test tubes The test tubes (dimensions DN 8 to DN 150) can be threaded with an external taper thread as per ISO 7-1 (but with the pressure tap length indicated in Table 1) for use with threaded end valves, and also in order to adapt threaded flange
38、s for flanged valves. Table 1 Tube sizes Nominal size of valve DN Nominal size of tube mm Thread size Gauge length mm 8 13,5 2,3 11,0 10 17,2 2,3 11,515 21,3 2,6 15,0 20 26,9 2,6 16,5 25 33,7 3,2 1 19,0 32 42,4 3,2 1 21,5 40 48,3 3,2 1 21,5 50 60,3 3,6 2 25,5 65 76,1 3,6 2 30,0 80 88,9 4,0 3 33,0 10
39、0 114,3 4,5 4 39,0 125 139,7 5,0 5 43,5 150 165,1 5,0 6 43,5 200 219,1 3,6 250 273,0 4,0 300 323,9 4,5 350 355,6 5,0 400 406,4 5,0 450 457,0 5,0 500 508,0 5,6 600 610,0 6,3 NOTE The nominal dimensions of DN 8 to DN 150 are in accordance with ISO 65, medium series and ISO 7598. The nominal dimensions
40、 of DN 200 to DN 600 are in accordance with ISO 4200, series C and EN ISO 1127. BS EN 1267:2012EN 1267:2012 (E) 9 4.3.2 Copper test tubes Table 2 Copper test tubes Nominal size of valve DN Nominal size of tube mm 8 10 0,810 12 1,015 15 1,0 15/20 18 1,020 22 1,025 28 1,5 32 35 1,540 42 1,550 54 1,5 D
41、imensions and tolerances shall be in accordance with EN 1057. Test tubes shall be straight. Their ends shall be cut square and deburred. Their internal surfaces shall be cleaned and free from obstructions visible to the naked eye. Inner diameters are determined by the valve manufacturer unless other
42、wise specified in a valve, product or application standard. For valves with low coefficient, the results obtained are affected by the test tube inner diameter. Therefore, the actual test tube inner diameter shall be mentioned (see Clause 7 b). NOTE When new test tubes are made, it is recommended to
43、make them in accordance with Table 1 and Table 2. 4.4 Pressure tappings The number of pressure taps is determined by the laboratory. At each pressure measurement section, there can be one, two or four tabs or a slot, provided that eccentricity is controlled. There should be four measurement taps for
44、 sizes greater than DN 300. Pressure tap diameters shall comply with Table 3 and length shall be at least twice the diameter. The measurement tap hole on test tube internal surface is sharp-edged and free from burrs. The measurement tape hole centreline cuts the axis of the test tube. The pressure t
45、ap hole centreline is square to axis with a maximum tolerance of 5. The inner diameter of connection tubes between taps and pressure measurement devices shall be at least twice the pressure tap hole diameter. To avoid dirt accumulation, no tap shall be located at measurement section bottom. Table 3
46、Pressure tap hole diameter DN Minimum mm Maximum mm 50 3 5 BS EN 1267:2012EN 1267:2012 (E) 10 4.5 Measurement devices The pressure loss shall be measured with a differential pressure sensor. The sensors or methods known further to calibration or by reference to other standards, providing measurement
47、s whose systematic uncertainty does not exceed the maximum permissible values, shall be used. The accuracy of measurement shall be a) upstream pressure, differential pressure and flow rate: 2 % of the read value, b) temperature measurement: 1 C. 4.6 Test fluid Test fluid shall be water with a temper
48、ature between 5 C and 40 C. 5 Test procedure 5.1 Test conditions 5.1.1 Permissible measurement fluctuations The permissible measurement fluctuation amplitude of each measurement value is given in Tables 4 and 5. If the fluctuations amplitude is greater than these values, the measurements shall be pe
49、rformed through a damper device. The damper installation shall not affect measurement accuracy: use a linear, symmetrical response device. Table 4 Differential pressure fluctuations Value of Fluctuations on p % 20 6 4 30 6,0 The arithmetic mean of all measurements shall be taken as measured value in
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