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1、BRITISH STANDARD BS EN 60534-8-3:1996 IEC 534-8-3: 1995 Industrial-process control valves Part 8: Noise considerations Section 3: Control valve aerodynamic noise prediction method The European Standard EN 60534-8-3:1995 has the status of a British Standard ICS 17.140.20; 23.060.40 Licensed Copy: she
2、ffieldun sheffieldun, na, Thu Nov 09 03:49:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 60534-8-3:1996 This British Standard, having been prepared under the direction of the Electrotechnical Sector Board, was published under the authority of the Standards Board and comes into effect on 15 Aug
3、ust 1996 BSI 08-1999 The following BSI references relate to the work on this standard: Committee reference GEL/65 Draft for comment 92/23188 DC ISBN 0 580 26011 9 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee GEL/65, up
4、on which the following bodies were represented: British Coal Corporation British Gas plc British Nuclear Fuels plc Electrical Contractors Association Electricity Association Energy Industries Council GAMBICA (BEAMA Ltd.) Health and Safety Executive Institution of Gas Engineers The following bodies w
5、ere also represented in the drafting of the standard, through subcommittees and panels: British Chemical Engineering Contractors Association British Pressure Gauge Manufacturers Association British Valve and Actuator Manufacturers Association Department of Trade and Industry (National Engineering La
6、boratory) Department of Trade and Industry (Services Management Division) Engineering Industries Association Institution of Electrical Engineers Institute of Materials Amendments issued since publication Amd. No.DateComments Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 03:49:58 GMT+00:00 2
7、006, Uncontrolled Copy, (c) BSI BS EN 60534-8-3:1996 BSI 08-1999i Contents Page Committees responsibleInside front cover National forewordii Foreword2 Text of EN 60534-8-33 List of referencesInside back cover Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 03:49:58 GMT+00:00 2006, Uncontrolle
8、d Copy, (c) BSI BS EN 60534-8-3:1996 ii BSI 08-1999 National foreword This British Standard has been prepared by Technical Committee GEL/65 and is the English language version of EN 60534-8-3:1995 Industrial-process control valves Part 8: Noise considerations Section 3: Control valve aerodynamic noi
9、se prediction method, published by the European Committee for Electrotechnical Standardization (CENELEC). It is identical with IEC 534-8-3:1995 published by the International Electrotechnical Commission (IEC). A British Standard does not purport to include all the necessary provisions of a contract.
10、 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 Publication referred toCorresponding British Standard BS EN 60534 Industrial-process control valves EN 60534-1:199
11、3 (IEC 534-1:1987) Part 1:1993 Control valve terminology and general considerations Part 2 Flow capacity EN 60534-2-1:1993 (IEC 534-2-1:1978) Section 1:1993 Sizing equations for incompressible fluid flow under installed conditions EN 60534-2-2:1993 (IEC 534-2-2:1980) Section 2:1993 Sizing equations
12、for compressible fluid flow under installed conditions EN 60534-2-3:1993 (IEC 534-2-3:1983) Section 3:1993 Test procedures IEC 534-8-1:1986BS 5793 Industrial-process control valves Part 8 Noise considerations Section 8.1:1986 Method for laboratory measurement of noise generated by aerodynamic flow t
13、hrough control valves Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, the EN title page, pages 2 to 44, 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 ind
14、icated in the amendment table on the inside front cover. Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 03:49:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 60534-8-3 October 1995 ICS 17.140.20; 23.060.40 Descriptors: Industrial process, co
15、ntrol valves, noise, aerodynamic flow English version Industrial-process control valves Part 8: Noise considerations Section 3: Control valve aerodynamic noise prediction method (IEC 534-8-3:1995) Vannes de rgulation des processus industriels Partie 8: Considrations sur le bruit Section 3: Calcul du
16、 bruit gnr par un dbit arodynamique (CEI 534-8-3:1995) Stellventile fr die Prozeregelung Teil 8: Geruschemission Hauptabschnitt 3: Berechnungsverfahren zur Vorhersage der aerodynamischen Gerusche von Stellventilen (IEC 534-8-3:1995) This European Standard was approved by CENELEC on 1995-09-20. CENEL
17、EC 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 ap
18、plication to the Central Secretariat or to any CENELEC 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 CENELEC member into its own language and notified to the Central Secret
19、ariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC
20、European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels 1995 Copyright reserved to CENELEC members Ref. No. EN 60534-8-3:1995 E Licensed Copy: she
21、ffieldun sheffieldun, na, Thu Nov 09 03:49:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 60534-8-3:1995 BSI 08-1999 2 Foreword The text of document 65B/231/DIS, future edition 1 of IEC 534-8-3, prepared by SC 65B, Devices, of IEC TC 65, Industrial-process measurement and control, was submitted to
22、 the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60534-8-3 on 1995-09-20. The following dates were fixed: Annexes designated “normative” are part of the body of the standard. Annexes designated “informative” are given for information only. In this standard, Annex ZA is normative and
23、Annex A and Annex B are informative. Annex ZA has been added by CENELEC. Contents Page Foreword2 Introduction3 1Scope and limitations3 2Normative references4 3Definitions4 4Symbols5 5Valves with standard trim7 5.1Pressures and pressure ratios7 5.2Regime definition8 5.3Preliminary calculations8 5.4Re
24、gime I (subsonic flow)9 5.5Regimes II to V (common calculations)10 5.6Noise calculations12 5.7Calculation flow chart14 6Valves with noise reducing trim14 6.1Introduction14 6.2Single stage, multiple flow passage trim14 6.3Single flow path, multistage pressure reduction trim (two or more throttling st
25、eps)15 6.4Multi-path, multistage trim (two or more passages and two or more stages)16 6.5Valves not included in this section16 Annex A (informative) Calculation examples19 Annex B (informative) Bibliography42 Annex ZA (normative) Normative references to international publications with their correspo
26、nding European publications43 Figure 1 Single stage, multiple flow passage trim17 Figure 2 Single flow path, multistage pressure reduction trim17 Figure 3 Multi-path, multistage trim (two or more passages and two or more stages)18 Table 1 Numerical constants N9 Table 2 Typical values of valve style
27、modifier Fd (full size trim)9 latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement(dop) 1996-07-01 latest date by which the national standards conflicting with the EN have to be withdrawn(dow) 1996-07-01 Licensed Copy:
28、 sheffieldun sheffieldun, na, Thu Nov 09 03:49:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 60534-8-3:1995 BSI 08-19993 Introduction The mechanical stream power, as well as acoustical efficiency factors, are calculated for various flow regimes. These acoustical efficiency factors give the propor
29、tion of the mechanical stream power which is converted into internal sound power. This method also provides for the calculation of the internal sound pressure and the peak frequency for this sound pressure, which is of special importance in the calculation of the pipe transmission loss. At present,
30、a common requirement by valve users is the knowledge of the sound pressure level outside the pipe, typically 1 m downstream of the valve and 1 m from the pipe wall. This section offers a method to establish this value. The equations in this section make use of the valve sizing factors as used in IEC
31、 534-1, IEC 534-2, and IEC 534-2-2. In the usual control valve, little noise travels through the wall of the valve. The noise of interest is only that which travels downstream of the valve and inside of the pipe and then escapes through the wall of the pipe to be measured typically at 1 m downstream
32、 of the valve body and 1 m away from the outer pipe wall. Although this prediction method cannot guarantee actual results in the field, it yields calculated predictions within 5 dB(A) for the majority of noise data from tests under laboratory conditions (reference IEC 534-8-1). The bulk of the test
33、data used to validate the method was generated using air at moderate pressures and temperatures; however, it is believed that the method is generally applicable to other gases and vapours and at higher pressures. Uncertainties become greater as the fluid behaves less perfectly for extreme temperatur
34、es and for downstream pressures far different from atmospheric, or near the critical point. The equations include terms which account for fluid density and the ratio of specific heat. NOTELaboratory air tests conducted with up to 1 830 kPa (18,3 bar) upstream pressure and up to 1 600 kPa (16,0 bar)
35、downstream pressure and steam tests up to 225 C showed good agreement with the calculated values. The transmission loss equations are based on a rigorous analysis of the interaction between the sound waves existing in the pipe and the many coincidence frequencies in the pipe wall. The wide tolerance
36、s in pipe wall thickness allowed in commercial pipe severely limit the value of the very complicated mathematical approach required for a rigorous analysis; therefore, a simplified method is used. Example calculations are given in Annex A. This method is based on the IEC standards listed in clause 2
37、 and the references given in Annex B. 1 Scope and limitations This section of International Standard IEC 534-8 establishes a theoretical method to predict the external sound-pressure level generated in a control valve by the flow of compressible fluids. This method considers only single-phase dry ga
38、ses and vapours and is based on the perfect gas laws. This section addresses only the noise generated by aerodynamic processes in valves and in the connected piping. It does not consider any noise generated by reflections, mechanical vibrations, unstable flow patterns, and other unpredictable behavi
39、our. At this time, predictions are limited to a downstream maximum velocity in the valve outlet port of 0,3 Mach. Ideal straight pipe is assumed downstream. The method is applicable to the following single-stage valves: globe (single and double seated), butterfly, angle, rotary plug (eccentric, sphe
40、rical), ball, and valves with cage trims. Specifically excluded are the full bore ball valves where the product FpC exceeds 50 % of the rated flow coefficient. For limitations on special low noise trims not covered by this section, see 6.5. Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 03:4
41、9:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 60534-8-3:1995 4 BSI 08-1999 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this section of IEC 534-8. At the time of publication, the editions indicated we
42、re valid. All normative documents are subject to revision, and parties to agreements based on this section of IEC 534-8 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. Members of IEC and ISO maintain registers of currentl
43、y valid normative documents. IEC 534-1:1987, Industrial-process control valves Part 1: Control valve terminology and general considerations. IEC 534-2:1978, Industrial-process control valves Part 2: Flow capacity Section 1: Sizing equations for incompressible fluid flow under installed conditions. I
44、EC 534-2-2:1980, Industrial-process control valves Part 2: Flow capacity Section 2: Sizing equations for compressible fluid flow under installed conditions. IEC 534-2-3:1983, Industrial-process control valves Part 2: Flow capacity Section 3: Test procedures. IEC 534-8-1:1986, Industrial-process cont
45、rol valves Part 8: Noise considerations Section 1: Laboratory measurement of noise generated by aerodynamic flow through control valves. 3 Definitions For the purpose of this International Standard, all of the definitions given in other parts of IEC 534 shall apply with the addition of the following
46、: 3.1 acoustical efficiency the ratio of the stream power converted into sound to the stream power of the mass flow 3.2 first coincidence frequency the lowest frequency at which the acoustic and structural axial wave numbers are equal for a given circumferential mode, thus resulting in the minimum t
47、ransmission loss 3.3 fluted vane butterfly valve a butterfly valve which has flutes (grooves) on the face(s) of the disk. These flutes are intended to shape the flow stream without altering the seating line or seating surface 3.4 independent flow passage a flow passage where the exiting flow is not
48、affected by the exiting flow from adjacent flow passages 3.5 peak frequency the frequency at which the internal sound pressure is a maximum 3.6 valve style modifier Fd the ratio of the hydraulic diameter of a single flow passage to the diameter of a circular orifice, the area of which is equivalent
49、to the sum of areas of all identical flow passages at a given travel Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 03:49:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 60534-8-3:1995 BSI 08-19995 4 Symbols SymbolDescriptionUnit AArea of a single flow passagem2 AnTotal flow area of last stage of multistage trim with n stages at given travel m2 CFlow coefficient (Kv and Cv)Various (See IEC 534-1) CnFlow coefficient for last stage of multistage trim with n stagesVarious (See IEC 534-1) cvcSpeed of sound in the ven