1、BS ISO21018-3:2008ICS 23.100.60NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDHydraulic fluid power Monitoring thelevel of particulatecontamination of thefluidPart 3: Use of the filter blockagetechniqueThis British Standardwas published under theauthority of th
2、e StandardsPolicy and StrategyCommittee on 31 July 2008 BSI 2008ISBN 978 0 580 53995 4Amendments/corrigenda issued since publicationDate CommentsBS ISO 21018-3:2008National forewordThis British Standard is the UK implementation of ISO 21018-3:2008. Itsupersedes BS 3406-9:1997 which is withdrawn.The
3、UK participation in its preparation was entrusted to TechnicalCommittee MCE/18/-/6, Contamination control.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionsof a contract. Users are
4、 responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.BS ISO 21018-3:2008Reference numberISO 21018-3:2008(E)ISO 2008INTERNATIONAL STANDARD ISO21018-3First edition2008-04-15Hydraulic fluid power Monitoring the level of particulate con
5、tamination of the fluid Part 3: Use of the filter blockage technique Transmissions hydrauliques Surveillance du niveau de pollution particulaire des fluides Partie 3: Technique de colmatage de filtre BS ISO 21018-3:2008ISO 21018-3:2008(E) PDF disclaimer This PDF file may contain embedded typefaces.
6、In accordance with Adobes licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In downloading this file, parties accept therein the responsibility of not infringing A
7、dobes licensing policy. The ISO Central Secretariat accepts no liability in this area. Adobe is a trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were optimized f
8、or printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below. COPYRIGHT PROTECTED DOCUMENT ISO 2008 All rights reserved. Unless o
9、therwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester. ISO copyr
10、ight office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2008 All rights reservedBS ISO 21018-3:2008ISO 21018-3:2008(E) ISO 2008 All rights reserved iiiContents Page Foreword iv Introduction v 1
11、 Scope . 1 2 Normative references . 1 3 Terms and definitions. 2 4 Health and safety 2 4.1 General. 2 4.2 Electrical power 2 4.3 Mechanical fluid power 2 4.4 Process liquids . 2 5 Principle of filter blockage technique. 3 6 Equipment . 3 6.1 General. 3 6.2 Equipment for on-line and off-line calibrat
12、ion and verification . 3 7 Operating procedures 5 7.1 General. 5 7.2 Operating from a pressurized line 5 7.3 Procedure for operating from a system reservoir. 6 7.4 Operating from a bulk container . 6 7.5 Operating from a sample bottle. 7 8 Calibration and verification procedure. 8 8.1 General princi
13、ples. 8 8.2 Equipment required 8 8.3 Preliminary procedures 8 8.4 Preparation of dust sample . 9 8.5 On-line calibration/verification procedure . 9 8.6 Verification of correct operation . 10 9 Calibration and/or verification. 11 10 Test report . 12 11 Identification statement 12 Annex A (informative
14、) Examples of use and applicability of the filter blockage technique. 13 BS ISO 21018-3:2008ISO 21018-3:2008(E) iv ISO 2008 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of pre
15、paring International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in
16、 liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical 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
17、 of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention
18、 is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 21018-3 was prepared by Technical Committee ISO/TC 131, Fluid power systems, Subcommittee SC 6, Contaminat
19、ion control. ISO 21018 consists of the following parts, under the general title Hydraulic fluid power Monitoring the level of particulate contamination of the fluid: Part 1: General principles Part 3: Use of the filter blockage technique A Part 2, dealing with the calibration and verification proced
20、ure for field contamination monitoring, and a Part 4, dealing with the use of the light extinction technique, are under development. BS ISO 21018-3:2008ISO 21018-3:2008(E) ISO 2008 All rights reserved vIntroduction In hydraulic fluid power systems, power is transmitted through a liquid under pressur
21、e within a closed circuit. The liquid is both a lubricant and power-transmitting medium. The presence of solid contaminant particles in the liquid interferes with the ability of the hydraulic liquid to lubricate and causes wear. The extent of contamination in the liquid has a direct bearing on the p
22、erformance and reliability of the system and should be controlled to an appropriate level. Quantitative determination of particulate contamination requires precision both in obtaining a representative sample of the liquid and the measurement of the contamination. The awareness of the benefits of cle
23、anliness monitoring has led to the development of instruments that operate on-line (i.e. directly connected to a system) in an attempt to reduce measurement errors that are inherent with bottle samples. Automatic particle counters (APC) and monitors have been developed and are extensively used. Unfo
24、rtunately, the hydraulic liquids in many systems might not be suitable for this method of measurement as the optical interfaces created by two-phase liquids (emulsions), immiscible liquids (water in oil and vice versa) and air in all liquids, interfere with the operation of the APC and give incorrec
25、t data. Instruments using the filter blockage principle were developed specifically to provide an alternative on-line instrument in applications where light extinction or scattering techniques are not suitable. The principle used is that the rate of filter blockage is related to the number of captur
26、ed particles whose size is larger than the pore size of the filters. The filter blockage technique does not directly measure the size of individual particles and so the principle of direct traceability does not apply. Instruments using this technique are becoming widely used in industry and an Inter
27、national Standard is required in order to standardize operating procedures. This part of this ISO 21018 defines procedures for the use of filter blockage instruments in evaluating the cleanliness level of a hydraulic liquid. It also includes procedures for calibrating and verifying that the instrume
28、nts are operating correctly to ensure consistent results and also closer correlation with on-line or in-line instruments using the light extinction principle. BS ISO 21018-3:2008BS ISO 21018-3:2008INTERNATIONAL STANDARD ISO 21018-3:2008(E) ISO 2008 All rights reserved 1Hydraulic fluid power Monitori
29、ng the level of particulate contamination of the fluid Part 3: Use of the filter blockage technique 1 Scope This part of ISO 21018 specifies a method for the semi-quantitative determination of the particulate contamination level using the filter blockage technique (also known as the mesh-obscuration
30、 method or the pore-blockage technique) either on-line or off-line in containers. It also defines procedures for calibrating the instruments and verifying their correct operation both in the laboratory and in service. In general, the techniques described in this part of ISO 21018 are suitable for mo
31、nitoring a) the general cleanliness level in hydraulic systems, b) the progress in flushing operations, c) support equipment and test rigs. The use of this method is applicable to all single- or multi-phase liquid systems. 2 Normative references The following referenced documents are indispensable f
32、or the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 3722, Hydraulic fluid power Fluid sample containers Qualifying and controlling cleaning methods ISO
33、 4021, Hydraulic fluid power Particulate contamination analysis Extraction of fluid samples from lines of an operating system ISO 5598, Fluid power systems and components Vocabulary ISO 11171, Hydraulic fluid power Calibration of automatic particle counters for liquids ISO 11943:1999, Hydraulic flui
34、d power On-line automatic particle-counting systems for liquids Methods of calibration and validation ISO 12103-1:1997, Road vehicles Test dust for filter evaluation Part 1: Arizona test dust ISO 21018-1, Hydraulic fluid power Monitoring the level of particulate contamination of the fluid Part 1: Ge
35、neral principles BS ISO 21018-3:2008ISO 21018-3:2008(E) 2 ISO 2008 All rights reserved3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 5598 and ISO 21018-1 and the following apply. 3.1 blockage restriction to flow through a filter caused by the captur
36、e of particles 3.2 extraneous contamination contamination that is not an integral part of the sample being analysed and is from another source NOTE It unrepresentatively increases the level of contamination. 4 Health and safety 4.1 General Operate the instrument in accordance with the manufacturers
37、instructions and follow local health and safety procedures at all times. 4.2 Electrical power Take care when connecting the instrument to an electrical power source and follow the manufacturers instructions. Ensure that the correct safety fuse is fitted. 4.3 Mechanical fluid power Instruments shall
38、be connected to pressurized lines in accordance with the instrument manufacturers instruction and in such a manner that the connection is secure and leak-free. Any connectors used shall be suitable for the pressure at the point of sampling. Internal pressure shall be dissipated before removing any f
39、ittings or closures. NOTE See 7.2 for guidance regarding sampling from pressurized lines. 4.4 Process liquids 4.4.1 Volatile liquids Flammable liquids shall be used a) in accordance with the relevant material safety data sheet (MSDS), b) at a temperature below the stated flash point, c) away from po
40、tential sources of ignition. 4.4.2 Solvents Solvents shall be used in well-ventilated areas and the generation of aerosol mists shall be avoided. BS ISO 21018-3:2008ISO 21018-3:2008(E) ISO 2008 All rights reserved 34.4.3 Electrical earthing/grounding Equipment used for filtering or dispensing solven
41、ts or any volatile flammable liquid shall be electrically earthed/grounded so as to avoid the risk of static discharge near the jet. 4.4.4 Environmental All liquids and substances shall be disposed of in accordance with local environmental procedures. Spillage shall be cleaned-up as detailed in the
42、relevant MSDS. 4.4.5 Chemical compatibility Ensure that all chemicals and fluids used in the various processes are chemically compatible with each other and with any equipment used. 5 Principle of filter blockage technique The filter blockage technique shall be based on either of the following princ
43、iples: a) constant differential pressure across the filter: The change in flow through a filter is measured as it gradually becomes blocked by particles in a known volume of liquid. A change in flow relates to the quantity of particles that are removed from the liquid by the filter; or, b) constant
44、flow through the filter: The differential pressure across the filter is measured as it gradually becomes blocked by particles in a known volume of liquid. The change in differential pressure relates to the quantity of particles removed from the liquid by the filter. Particles that are retained on th
45、e surface of the filter are removed by back-flushing prior to performing the next analysis. NOTE 1 Individual particles are not detected and any reported numerical data is only an assessment of the number of particles from the detection process. NOTE 2 If the liquid being analysed contains contamina
46、nts other than particulate (e.g. gels or non-soluble additives), these can be removed by the instrument filters and affect the output data. 6 Equipment 6.1 General If the analysis is performed using sample bottles or containers (see 7.5), sampling apparatus (6.2.1) may be required. Such equipment av
47、oids adding contamination when the inlet hose is inserted into the sample bottle. For the process of calibration and verification of correct operation, use the equipment detailed in 6.2. 6.2 Equipment for on-line and off-line calibration and verification 6.2.1 Bottle sampling apparatus, for transfer
48、ring the calibration/verification sample to the instrument. If a pressure chamber is used to force the liquid through the device at constant pressure, a suitable source of filtered and regulated air is required. BS ISO 21018-3:2008ISO 21018-3:2008(E) 4 ISO 2008 All rights reserved6.2.2 Calibration/v
49、erification dust, test dust, designated ISO 12103-A3, used for calibration and/or verification shall meet the requirements ISO 12103-1:1997, Clause 3, and have a size distribution measured using an automatic particle counter (APC) calibrated in accordance with ISO 11171 or ISO 11943. 6.2.3 Flushing liquid, separate liquid for flushing the instrument prior to verification. This liquid shall have a required cleanliness level (RCL) of less than 10 particles sized W 6 m(c)/ml. NOTE m(c) refers to the sizes of
