1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58ICS 23.100.60; 71.100.20Filters for compressed air Test methods Part 1: Oil aerosolsBRITISH STANDAR
2、DBS ISO 12500-1:2007BS ISO 12500-1:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 July 2007 BSI 2007ISBN 978 0 580 53130 9Amendments issued since publicationAmd. No. Date Commentscontract. Users are responsible for its correct applica
3、tion.Compliance with a British Standard cannot confer immunity from legal obligations.National forewordThis British Standard is the UK implementation of ISO 12500-1:2007.The UK participation in its preparation was entrusted to Technical Committee MCE/8, Compressors, pneumatic tools, pneumatic machin
4、es and vacuum technology.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a INTERNATIONALSTANDARDISO12500-1First edition2007-06-01Reference numberISO 12500-1:2007(E)Filters f
5、or compressed air Test methods Part 1:Oil aerosolsFiltres pour air comprim Mthodes dessai Partie 1: Arosols dhuileBS ISO 12500-1:2007iiiiiContents Page1 Scope 12 Normative references 13 Terms and definitions 24 Units and symbols . 25 Reference conditions 36 Test requirements 37 Test method 58 Uncert
6、ainty . 69 Test report 7Annex A (informative) Sample test report form . 8Bibliography . 9BS ISO 12500-1:2007ivForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies(ISO member bodies). The work of preparing International Standards is n
7、ormally carried out through ISOtechnical committees. Each member body interested in a subject for which a technical committee has beenestablished has the right to be represented on that committee. International organizations, governmental andnon-governmental, in liaison with ISO, also take part in t
8、he work. ISO collaborates closely with the InternationalElectrotechnical Commission (IEC) on all matters of electrotechnical standardization.International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.The main task of technical committees is to prepare In
9、ternational Standards. Draft International Standardsadopted by the technical committees are circulated to the member bodies for voting. Publication as anInternational Standard requires approval by at least 75 % of the member bodies casting a vote.Attention is drawn to the possibility that some of th
10、e elements of this document may be the subject of patentrights. ISO shall not be held responsible for identifying any or all such patent rights.ISO 12500-1 was prepared by Technical Committee ISO/TC 118, Compressors and pneumatic tools, machinesand equipment, Subcommittee SC 4, Quality of compressed
11、 air.ISO 12500 consists of the following parts, under the general title Filters for compressed air Test methods: Part 1: Oil aerosols Part 2: Oil vapours Part 3: ParticulatesBS ISO 12500-1:2007vIntroductionOil aerosols are a typical contaminant found in compressed air streams. Coalescing filters are
12、 designed toremove oil aerosols from compressed air.The most important performance characteristics are the ability of the filter to remove oil aerosols from the airstream and the amount of pressure drop caused by the filter as compressed air flows through it when the filterelement is saturated with
13、oil. This part of ISO 12500 provides a means of comparing the performance of filters.BS ISO 12500-1:2007blank1Filters for compressed air Test methods Part 1:Oil aerosols1ScopeThis part of ISO 12500 specifies the test layout and test procedures required for testing coalescing filters usedin compresse
14、d-air systems to determine their effectiveness in removing oil aerosols.This part of ISO 12500 provides the means to indicate performance characteristics of the pressure drop and thecapability of removing oil aerosols.This part of ISO 12500 defines one method of presenting filter performance as outl
15、et oil aerosol concentrationstated in milligrams per cubic metre from results obtained under standard rating parameters.2 Normative referencesThe following referenced documents are indispensable for the application of this document. For datedreferences, only the edition cited applies. For undated re
16、ferences, the latest edition of the referenced document(including any amendments) applies.ISO 1219-1, Fluid power systems and components Graphic symbols and circuit diagrams Part 1: Graphicsymbols for conventional use and data-processing applicationsISO 2602, Statistical interpretation of test resul
17、ts Estimation of the mean Confidence intervalISO 2854, Statistical interpretation of data Techniques of estimation and tests relating to means andvariancesISO 3649:1980, Cleaning equipment for air or other gases VocabularyISO 5598, Fluid power systems and components VocabularyISO 7000, Graphical sym
18、bols for use on equipment Index and synopsisISO 71831), Compressed-air dryers Specifications and test methodsISO 8573-1:2001, Compressed air Part 1: Contaminants and purity classesISO 8573-2, Compressed air Part 2: Test methods for oil aerosol contentISO 14644-3:2005, Cleanrooms and associated contr
19、olled environments Part 3: Test methods1) To be published. (Revision of ISO 7183:1986)BS ISO 12500-1:200723 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 7183, ISO 5598 and the followingapply.3.1 ambient temperaturetemperature of the air surrounding t
20、he filter under test3.2 coalescingaction by which liquid particles in suspension unite to give particles of greater volumeISO 3649:1980, definition 133.3 contaminantany solid, liquid or gas that adversely affects the system3.4 filterapparatus for separation or removal of contamination from a compres
21、sed air or gas stream3.5 pressure dropdifferential pressuredifference between inlet and outlet pressure of a component, measured under specified conditions3.6 equivalent flow velocityflow at which, when the test filter is operated at a (e) test pressure, an equal velocity to that forthe device would
22、 be achieved when operated at a rated pressure and flow other than the test pressure3.7 wall flowthat proportion of liquid contamination no longer suspended within the air flow of the pipe4 Units and symbolsGeneral use of SI units (Systme international dunits, see ISO 1000) as given throughout this
23、part ofISO 12500 is recommended. However, in agreement with accepted practice in the pneumatic field, somenon-preferred SI units, accepted by ISO, are also used.NOTE bar (e) is used to indicate effective pressure above atmospheric.The graphic symbols on diagrams are in accordance with ISO 1219-1 and
24、 ISO 7000.p700 kPa 7 bar1 bar = 100 000 Pa1 l (litre) = 0,001 m3BS ISO 12500-1:200735 Reference conditionsThe reference conditions for gas volumes shall be:a) air temperature ;b) absolute air pressure (a);c) relative water vapour pressure 0.6 Test requirements6.1 Standard rating parametersThe standa
25、rd rating parameters are as identified in Table 1.6.2 Inlet air velocityTesting for aerosol removal shall be carried out at the flow rate which the manufacturer specifies as themaximum rated working flow for continuous operation for each particular filter model.To maintain turbulent flow and minimis
26、e aerosol settling, the minimum Reynolds number in the air stream in theinlet pipe shall be 4 000.The Reynolds number, , shall be calculated using Equation (1);(1)Table 1 Standard rating parametersReporting parametersUnits Rating conditionscMaintain within of actual gauge valueInstrument accuracy at
27、 test conditionsInlet temperature 20Inlet pressure kPa bar (e) 700 (7) (0,1)()Ambient temperature20Minimum air puritya ISO 8573-1:2001, class 2 6 1dAir flow for testing m3/h rated flowof gauge readingInlet oil aerosol concentrationbcmg/m310 40of gauge readingPressure drop Pa (mbar) not applicable no
28、t applicableof gauge readingaMinimum air purity to the inlet of the oil aerosol generator, to ensure there is no liquid water present on the inlet of the test filter.bMineral oil lubricants meeting the requirements of ISO 3448, Viscosity Grade 46 and which are typical of compressor oils may be used.
29、cSelection based on the type and performance of the compressor representative of those which may be found in usedThe first number represents the solid-particle classification; the second, the humidity classification; and the third, the total oilclassification.20C100 kPa 1 barC 5 2C 10 10 kPa 0,1 bar
30、C 5 2C100 % 2% 4% 10 % 10 % 10 %ReRe =DvBS ISO 12500-1:20074whereis the internal pipe diameter, expressed in metres;is the flow velocity, expressed in metres per second;is the density in kilogrames per cubic metres;is the dynamic viscosity, expressed in pascal-seconds.If a filter employs multiple el
31、ements, testing carried out on a filter with an element at the maximumrecommended flow rate for that particular element may be taken as representative of the results fora multi-element filter using the same element.6.3 Inlet air flowFor the testing of filters that have their maximum flow rating quot
32、ed at a pressure other than (e), themeasurement for oil-aerosol removal can be made using equivalent flow velocity at rated pressure identified bythe manufacturer for the filter under test.The test flow rate, , at reference conditions, expressed in cubic metres per hour, is calculated accordingto Eq
33、uation (2):(2)whereis rated flow rate, at reference conditions, expressed in cubic metres per hour;is absolute test pressure, expressed in bar (a);is absolute rated pressure, expressed in bar (a);is the compressibility factor of air at rated pressure and , dimensionless.Dv7 barqV e,REFqV e,REF=qV n,
34、REFTpepnqV n,REFpepnT20CBS ISO 12500-1:200757 Test method7.1 Test equipment arrangementThe circuit diagram of the test equipment is shown in Figure 1.7.2 Test challenge concentrationSet all controls of the test rig to the standard rating parameters given in Table 1. The aerosol generator isdesigned
35、to provide a poly-disperse oil-aerosol distribution having an average size in the range toby particle count. The aerosol generator is designed to give a normal mean particle-size distribution ofbetween and by particle count to disperse aerosols and the output adjusted to give the testconcentration r
36、equired in Table 1.Care shall be exercised to ensure that all of the challenge oil concentration delivered to the test filter is inaerosol form within the range detailed above and, where necessary, provision shall be made within the aerosolgenerator system to prevent wall flow into the test apparatu
37、s.Key1 compressed air supply2 pressure regulator3 temperature sensing/measuring4 dew point sensing/measuring5 full-flow ball valve6 pressure sensing/measuring7 differential pressure gauge8 sample test point9 multi-turn flow control valve10 flow sensing/measuring11 silencer12 ambient temperature sens
38、ing/measuring13 aerosol generator14 pressure measuring tube15 filter under testaDetails of the construction of the measuring tubes are given in ISO 7183.Figure 1 Typical layout of test equipment0,15m0,4m0,15m 0,4mBS ISO 12500-1:200767.3 Test procedureAt least three examples of each model shall be te
39、sted. The test shall be repeated three times on the same filterelement and the results averaged.7.4 Conditioning of the filter element under testThe coalescing filter element shall reach a state of equilibrium before testing is started. Conditioning the filterunder test using a challenge aerosol con
40、centration greater than that given in Table 1 is permitted; however, thepreferred procedure is to set the actual characteristics and allow the filter to become conditioned by setting thegenerator to provide the test challenge level. Concentrations above the test challenge levels can causeexcessive o
41、il concentration in the outlet air, possibly causing misleading results when the test program isundertaken.Equilibrium is considered to have been achieved when liquid oil is observed in the bottom of the filter housing inwhich the filter under test is contained and the rate of change in pressure dro
42、p is less than of themeasured pressure drop.The pressure drop across the test filter shall be recorded. If required, the air flow may be adjusted.7.5 Determination of oil aerosol concentrationThe determination of oil aerosol concentration shall be done in accordance with ISO 8573-2 or, alternatively
43、, asuitable white-light-scattering aerosol photometer according to ISO 14644-3:2005, Annex C that is capable ofsampling compressed air across the range of concentrations of interest can be used. Such an instrument willhave previously been calibrated using the test oil and shall be capable of samplin
44、g the air at the test pressure.Care shall also be exercised to ensure that the compressed-air sampling method follows the requirements asdetailed by ISO 8573-2, i.e. full-flow or iso-kinetic sampling.7.6 Determination of wet pressure dropThe wet pressure drop is determined at of rated flow when equi
45、librium is achieved with the aerosolgenerator operating and set to the conditions identified in Table 1.8 UncertaintyNOTE A calculation of the probable error, according to this clause is not always necessary.Due to the very nature of physical measurements, it is impossible to measure a physical quan
46、tity without erroror, in fact, to determine the true error of any one particular measurement. However, if the conditions of themeasurement are sufficiently well known, it is possible to estimate or calculate a characteristic deviation of themeasured value from the true value, such that it can be ass
47、erted with a certain degree of confidence that thetrue error is less than the said deviation. The value of such a deviation (normally a confidence limit)constitutes a criterion for the accuracy of the particular measurement.It is assumed that compensation can be made by corrections for all systemati
48、c errors that can occur in themeasurement of the individual quantities measured and of the characteristics of the air. A further assumption isthat the confidence limits in errors in reading and integration errors are negligible if the number of readings issufficient.The (small) systematic errors tha
49、t can occur are covered by the inaccuracy of measurements.Quality classifications and limits of error are often invoked for ascertaining the uncertainty of an individualmeasurement because apart from the exceptions (e.g. electrical transducers), they constitute only a fraction ofthe quality class or the limit of error.1 %/hr100 %95 %BS ISO 12500-1:20077The information about ascertaining the uncertainty of the measurement of the individual quantitie
