1、February 2011 Translation by DIN-Sprachendienst.English price group 16No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).I
2、CS 17.140.20; 91.120.20!$mHL“1743741www.din.deDDIN ISO 15665Acoustics Acoustic insulation for pipes,valves and flanges (ISO 15665:2003 +Cor. 1:2004)English translation of DIN ISO 15665:2011-02Akustik Schalldmmung von Rohren, Ventilen und Flanschen (ISO 15665:2003 + Cor. 1:2004)Englische bersetzung v
3、on DIN ISO 15665:2011-02Acoustique Isolation acoustique des tuyaux, clapets et brides (ISO 15665:2003 + Cor. 1:2004)Traduction anglaise de DIN ISO 15665:2011-02www.beuth.deDocument comprises pagesIn case of doubt, the German-language original shall be considered authoritative.3902.11 A comma is used
4、 as the decimal marker. Contents Page National foreword .3 National Annex NA (informative) Bibliography.5 1 Scope 4 2 Normative references 4 3 Terms and definitions4 4 Classes of acoustic insulation .5 5 Guide to the reduction of noise from pipes 9 5.1 Required insertion loss: Design phase steps.9 5
5、.2 Required insertion loss: Operating plants 10 5.3 Length of acoustic insulation.11 5.4 Implications for piping design12 5.5 Derivation of overall noise reduction 13 5.6 Typical noise reduction values.15 6 Construction of typical acoustic insulation systems.16 6.1 General16 6.2 Cladding16 6.3 Porou
6、s layer .17 6.4 Support of the cladding.18 7 Installation 18 7.1 General18 7.2 Extent of insulation18 7.3 End caps .18 7.4 Acoustic enclosures19 7.5 Prevention of mechanical damage.19 8 Combined thermal and acoustic insulation 19 8.1 General19 8.2 Hot services19 8.3 Cold services19 9 Acoustic insula
7、tion constructions that meet the insulation class requirements20 9.1 General20 9.2 Materials .21 9.3 Vibration isolation material at pipe supports21 10 Testing of acoustic insulation systems.21 10.1 General21 10.2 Measurement method: Reverberation room .22 10.3 Test facility .22 10.4 Test specimen24
8、 10.5 Measurements24 10.6 Results 25 10.7 Information to be reported25 Annex A (informative) Equations for the calculation of the minimum required insertion loss DW,min of the insulation classes27 Annex B (informative) General construction of acoustic insulation28 Annex C (informative) Examples of t
9、ypical construction details29 Bibliography 39 2 DIN ISO 15665:2011-02 National foreword This standard has been prepared by Technical Committee ISO/TC 43 “Acoustics” (Secretariat: DS, Denmark). The responsible German body involved in its preparation was the Normenausschuss Akustik, Lrmminderung und S
10、chwingungstechnik im DIN und VDI (Acoustics, Noise Control and Vibration Engineering Standards Committee in DIN and VDI), Working Committee NA 001-02-03 AA Schallausbreitung und Lrmminderung in Gebuden, in Arbeitssttten und im Freien. After careful consideration, the German mirror committee has deci
11、ded to publish this International Standard as a German Standard. The national standard implementing the International Standard includes not only ISO 15665:2003 but also ISO 15665:2003 Technical Corrigendum 1, published in 2004-03. National footnotes The DIN Standards corresponding to the Internation
12、al Standards referred to in this document are as follows: ISO 354 DIN EN ISO 354 ISO 3741 DIN EN ISO 3741 ISO 3744 DIN EN ISO 3744 National Annex NA (informative) Bibliography DIN EN ISO 354, Acoustics Measurement of sound absorption in a reverberation room DIN EN ISO 3741, Acoustics Determination o
13、f sound power levels of noise sources using sound pressure Precision methods for reverberation rooms DIN EN ISO 3744, Acoustics Determination of sound power levels of noise sources using sound pressure Engineering method in an essentially free field over a reflecting plane 3 DIN ISO 15665:2011-02 po
14、int out the remaining errors which, from Germanys point of view, still need to be corrected. Acoustics Acoustic insulation for pipes, valves and flanges 1 Scope This International Standard defines the acoustic performance of three classes (Classes A, B and C) of pipe insulation. It also specifies th
15、ree types of construction that will meet these acoustic performance classes. Furthermore, this International Standard defines a standardized test method for measuring the acoustic performance of any type of construction, thereby allowing existing and new insulation constructions to be rated against
16、the three classes. This International Standard is applicable to the acoustic insulation of cylindrical steel pipes and to their piping components. It is valid for pipes up to 1 m in diameter and a minimum wall thickness of 4,2 mm for diameters below 300 mm, and 6,3 mm for diameters from 300 mm and a
17、bove. It is not applicable to the acoustic insulation of rectangular ducting and vessels or machinery. This International Standard covers both design and installation aspects of acoustic insulation and provides guidance to assist noise control engineers in determining the required class and extent o
18、f insulation needed for a particular application. It gives typical examples of construction methods, but the examples are for information only and not meant to be prescriptive. This International Standard emphasises the aspects of acoustic insulation that are different from those of thermal insulati
19、on, serving to guide both the installer and the noise control engineer. Details of thermal insulation are beyond the scope of this International Standard. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the
20、edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 354, Acoustics Measurement of sound absorption in a reverberation room ISO 3741:1999, Acoustics Determination of sound power levels of noise sources using sound pressu
21、re Precision methods for reverberation rooms ISO 3744, Acoustics Determination of sound power levels of noise sources using sound pressure Engineering method in an essentially free field over a reflecting plane 3 Terms and definitions For the purposes of this document, the following terms and defini
22、tions apply. 3.1 piping cylindrical pipes and fittings such as valves, flanges, bellows and supports 4 DIN ISO 15665:2011-02 3.2 acoustic insulation acoustic lagging outer cover applied with the aim of reducing the noise radiated from the pipe NOTE Acoustic insulation typically consists of a sound-a
23、bsorbing and/or resilient material (“porous layer”) on the piping and an impermeable outer cover (“cladding”). 3.3 airflow resistivity pressure drop per unit thickness of a porous material encountered by a steady air flow of unit velocity through the material NOTE 1 Airflow resistivity equals the pr
24、essure drop divided by the product of the air velocity and the thickness of the sample. NOTE 2 The unit of airflow resistivity is Ns/m4= Pas/m2. NOTE 3 Procedures for determining the flow resistivity are described in ISO 9053. 3.4 insertion loss sound power insulation DWfor any octave or one-third-o
25、ctave band, the difference, in decibels, in the sound power level radiated from a noise source before and after the application of the acoustic insulation NOTE See Note to 3.5. 3.5 sound pressure insulation Dp for any octave or one-third-octave band, the difference, in decibels, in the sound pressur
26、e level, at a specified position relative to the noise source, before and after the application of the acoustic insulation NOTE For noise sources located indoors, especially for laboratory measurements, the determination of sound power insulation DWis most appropriate. DWcan be determined in a rever
27、beration room or with sound intensity measurements. For piping outdoors in field situations, the determination of sound pressure insulation Dpis a less accurate but more practical approach. The sound pressure measurement positions should be selected in relation to the design goal of the acoustic ins
28、ulation, which will in general be in a circle around the piping. It is preferable to use a measurement distance of 1 m from the pipe surface, or 2,5 times the pipe diameter for pipes less than 0,33 m in diameter, to minimize near field measurement effects. The measurement position should be the same
29、 with and without the acoustic insulation. If the radiation patterns of both the untreated and acoustical insulated piping are “cylindrical omni-directional”, the two measures (DWand Dp) yield the same result. 4 Classes of acoustic insulation This clause defines three classes of acoustic insulation,
30、 denoted Classes A, B and C, in terms of requirements for minimum insertion loss. The minimum insertion loss is specified in Table 1 and illustrated in Figures 1 to 3. Equations for the approximate calculations of the required insertion loss (within 0,5 dB) are presented in Annex A. The insertion lo
31、ss of acoustic insulation is related to the diameter of the pipe on which it is applied. The pipe diameters are divided into three pipe size groups and the insulation class will consist of a letter/number combination indicating the diameter on which the insulation is applied. 5 DIN ISO 15665:2011-02
32、 The pipe sizes used are: less than 300 mm outside diameter; greater than or equal to 300 mm diameter but less than 650 mm; greater than or equal to 650 mm diameter but less than 1 000 mm. Table 1 Minimum insertion loss required for each class Octave band centre frequency, Hz 125 250 500 1 000 2 000
33、 4 000 8 000 Class Range of nominal diameter D mm Minimum insertion loss, dB A1 D r), in metres; S0= 1 m2; D is the outside diameter of the pipe, in metres; r is the distance from the pipe axis, in metres, preferably r = (1 + D), which is 1 m from pipe wall; (,)pL xr surface sound pressure level, in
34、 decibels, obtained by averaging over a specified measurement surface at a distance r from the axis of the pipe, at a distance x from the noise source, measured along the pipe in free-field condition. 9 DIN ISO 15665:2011-02 NOTE The preferred value for x is 1 m; where attenuation along the pipe is
35、considered negligible, larger values of x may also be used. If the pipe is long and cannot be measured over its entire length, it may be worth estimating the sound pressure level by measuring the sound pressure level near the source and taking the noise attenuation along the pipe into account. This
36、is expressed by the following formula (see reference 8): ( ) ( ),1,/dBppLxr L r xD= (2) where Lp(1,r) is the sound pressure level at a distance of 1 m away from the noise source, at the same distance r from pipe axis as in Lp(x,r); is the attenuation factor, in decibels. The value of can be 0,06 dB
37、for pipes carrying gas or vapour (attenuation of 3 dB for every 50 pipe diameters) and 0,017 for liquid (attenuation of 3 dB for every 175 pipe diameters), based on practical experience. If, for a particular application, evidence is available that the value for is different, this value shall be used
38、. The length of pipe should exceed (3D/) before attenuation is taken into account. On the basis of Equation (2), the sound power level LWof a long length of pipe can be shown to be: ()()01, 10 lg dB 14,4 dBWprDLs L rS = + +(3) where is the numerical value of the attenuation factor. NOTE 1 The comple
39、te equation for the relation between LW(s) and Lp(1,r) is: () ( )()0,1 /021, 10 lg dB 10 lg 1 10 dB0,1 In 10sDWprDLs L rS=+ +(4) It can be shown that Equation (4) will develop into Equation (1) for small values of (/)s D and into Equation (3) for very long pipes. NOTE 2 The errors involved in applyi
40、ng Equation (1) for pipes longer than (3D/) and in applying Equation (3) for shorter pipes is less than 3 dB. NOTE 3 Noise from piping can be transmitted by the fluid or by the pipe wall or both. The acoustic insulation systems are effective for both. The propagation of noise by the pipe wall is dif
41、ficult to predict. 5.1.4 Contribution to noise in reverberant spaces or environmental noise The contribution of the pipe to the noise in the reverberant space is calculated from its sound power level and should be added to the contributions from other sources. For environmental noise, the contributi
42、on of the pipe to the total sound power level of the plant, or to the sound pressure level at the neighbourhood point, should be calculated. 5.2 Required insertion loss: Operating plants In operating plants, the assessment of pipe noise may be based on measurements. Where the pipe noise is significa
43、ntly higher than the background noise, it may be measured directly as sound pressure levels. Again, piping upstream and downstream of the source shall be considered separately. 10 DIN ISO 15665:2011-02 If background noise is significant, pipe noise can often be determined with sound intensity measur
44、ements. However, in-situ sound intensity measurements of pipe noise may be difficult to perform and require special equipment and expertise. A third option is to assess the pipe noise by measuring the vibratory velocity level of the pipe surface and using the concept of radiation efficiency (see ref
45、erence 8): ( ) ( ), 10 lg dB 10 lg / 2 dBpvLxr L Dr=+ + (5) where Lv/v0= 5 108m/s; 10 lg is the radiation efficiency (10 lg is negative, as 0 1). For practical purposes, the value of can be derived from reference 8: 3114cDf =+(6) where c is the velocity of sound in air, in metres per second; f is th
46、e octave-band centre frequency, in hertz. NOTE This method is less preferred since estimates of radiation efficiency are inaccurate. It also requires special equipment and expertise. However, this may be the only available method for situations with high background noise levels or where space does n
47、ot permit accurate acoustic intensity measurements. 5.3 Length of acoustic insulation The noise radiated by the wall of a pipe is usually generated by equipment connected to the pipe, such as compressors, pumps, valves or ejectors. These noise sources may cause long sections of pipe to radiate noise
48、 because noise will propagate in the pipe with little attenuation. If the assessment of various aspects of noise control indicates that acoustic insulation of a pipe is required, the necessary reduction of pipe noise should be tabulated in octave bands. Reference to Clause 4 will then indicate which
49、 class of insulation is required. Pipes will usually have to be insulated from the noise source to (and sometimes including) the next silencer, vessel, heat exchanger, filter, etc., unless it can be shown that attenuation along the pipe has reduced the noise sufficiently at some point downstream and upstream of the source to render further insulation unnecessary. This may be the point where the contribution of the pipe to the noise level is below a target value, as according to Equation
