1、Designation: D4174 89 (Reapproved 2010)Standard Practice forCleaning, Flushing, and Purification of Petroleum FluidHydraulic Systems1This standard is issued under the fixed designation D4174; the number immediately following the designation indicates the year oforiginal adoption or, in the case of r
2、evision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers aid for the equipment manufacturer,the installer, the oil supplier and the o
3、perator in coordinatingtheir efforts towards obtaining and maintaining clean petro-leum fluid hydraulic systems. Of necessity, this practice isgeneralized due to variations in the type of equipment, build-ers practices, and operating conditions. Constant vigilance isrequired throughout all phases of
4、 design, fabrication, installa-tion, flushing, testing, and operation of hydraulic systems tominimize and reduce the presence of contaminants and toobtain optimum system reliability.1.2 This practice is presented in the following sequence:SectionScope 1Referenced Documents 2Significance and Use 3Def
5、initions 4Types of Contamination 5General 5.1Water 5.2Soluble Contaminants 5.3Insoluble Contaminants 5.4Lodged Contamination 5.4.2.1Suspended Contamination 5.4.2.2Contamination Control 6General 6.1Initial Filling 6.1.1In-Service Units 6.1.2Connection of Contamination Control System 6.1.3Piping to Co
6、ntamination Control System 6.1.4Contamination Control Procedures 6.2Full Flow Contamination Control 6.2.1Bypass Contamination Control 6.2.2Batch Contamination Control 6.2.3Contamination Control Processes 6.3Gravity 6.3.1Mechanical 6.3.2Centrifuge 6.3.2.1Filters 6.3.2.2Supplementary Methods 6.3.3Sect
7、ionLimitations of Contamination Control Devices 6.3.4Storage 7General 7.1Inspection 8General 8.1System Components 8.2Valves, Strainers and Coolers 8.2.1Sumps and Tanks 8.2.2Control Devices 8.2.3Pumps 8.2.4Flushing Program 9General 9.1Preparation of System for Flushing 9.2Oil Heating Prior to Flushin
8、g 9.3Selection of Flushing Oil 9.4System Operation Oil 9.4.1Special Flushing Oil 9.4.2Flushing Oil Selection Guide 9.4.3Flushing Procedure for New Systems 9.5Flushing Oil Charge 9.5.1Cleaning of Filtration Devices 9.5.2Cleaning of System Components 9.5.3System Flushing 9.5.4Draining of Flushing Oil
9、9.5.5Displacement Oil 9.5.6Interim Corrosion Protection 9.5.7New Fluid Charge 9.5.8Flushing of Used Systems 9.6General Guidelines 9.6.1Procedure 9.6.2System Maintenance 10Shipping 10.1Preinstallation 10.2In-Service Units 10.3Decision to Flush In-Service Hydraulic Systems 10.4Fluid Condition Monitori
10、ng 11Fluid Sampling Techniques 11.2Visual Inspection 11.3Laboratory Analysis 11.4Fluid Cleanliness Criteria 11.5General Information 12Filter Ratings 12.2Centrifuge Ratings 12.3Coalescence 12.4Vacuum Dehydration 12.5Adsorption 12.61.3 The values stated in SI units are to be regarded as thestandard. T
11、he values given in parentheses are for informationonly.1This practice is under the jurisdiction of ASTM Committee D02 on PetroleumProducts and Lubricants and is the direct responsibility of D02.N0.02 on IndustrialApplications.Current edition approved Oct. 1, 2010. Published November 2010. Originally
12、approved in 1982. Last previous edition approved in 2005 as D417489(2005).DOI: 10.1520/D4174-89R10.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.1.4 This standard does not purport to address all of thesafety concerns, if any, assoc
13、iated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D445 Test Method for Kinematic Viscosity of Transparentand
14、 Opaque Liquids (and Calculation of Dynamic Viscos-ity)D664 Test Method for Acid Number of Petroleum Productsby Potentiometric TitrationD974 Test Method for Acid and Base Number by Color-Indicator TitrationD1774 Test Method for Elastic Properties of Textile Fibers3D2709 Test Method for Water and Sed
15、iment in MiddleDistillate Fuels by CentrifugeD4006 Test Method for Water in Crude Oil by DistillationF311 Practice for Processing Aerospace Liquid Samples forParticulate Contamination Analysis Using Membrane Fil-tersF312 Test Methods for Microscopical Sizing and CountingParticles from Aerospace Flui
16、ds on Membrane FiltersF313 Test Method for Insoluble Contamination of Hydrau-lic Fluids by Gravimetric Analysis32.2 ANSI Standards:B93.2 Glossary of Terms for Fluid Power4B93.19 Method for Extracting Fluid Samples from theLines of an Operating Hydraulic Fluid Power System (forParticulate Contaminati
17、on Analysis)43. Terminology3.1 Definitions:3.1.1 absolute filtration ratingthe diameter of the largesthard spherical particle that will pass through a filter underspecified test conditions. This is an indication of the largestopening in the filter element.3.1.2 nominal filtration ratingan arbitrary
18、micrometrevalue indicated by a filter manufacturer. Due to lack ofreproducibility this rating is deprecated. (ANSI B93.2)4. Significance and Use4.1 Proper fluid condition is essential for the satisfactoryperformance and long life of the equipment. Prerequisites forproper lubrication and component pe
19、rformance are: (1)awell-designed hydraulic system, (2) the use of a good fluid, and(3) a maintenance program including proper filtration methodsto ensure that the fluid is free of contaminants. These prereq-uisites are meaningless unless the hydraulic system is initiallycleaned to a level that will
20、prevent component damage oninitial start up or when debris may be dislodged by any systemupset.4.2 The cleaning and flushing of both new and used systemsare accomplished by essentially the same procedure. In newsystems, the emphasis is on the removal of contaminantsintroduced during the manufacture,
21、 storage, field fabrication,and installation. In used systems, the emphasis is on theremoval of contaminants that are generated during operations,from failures that occur during operation; or contaminantsintroduced during overhaul.4.3 While the flushing and cleaning philosophies stated inthis practi
22、ce are applicable to all primary and servo hydraulicsystems, the equipment specified herein does not apply tocompact systems that use relatively small volumes of fluidunless they are servo systems where it is economically justi-fied.4.4 It should be emphasized that the established proceduresto be fo
23、llowed for flushing and cleaning the hydraulic systemsshould be accomplished through the cooperative efforts andagreement of the equipment manufacturer, the installer, theoperator, and the fluid supplier. No phase of these proceduresshould be undertaken without a thorough understanding of thepossibl
24、e effects of improper system preparation. The installa-tion and cleaning and flushing of the equipment should not beentrusted to persons lacking in experience.5. Types of Contamination5.1 GeneralHydraulic systems can become contaminatedfrom a variety of sources. Generally, there are five categories
25、ofcontamination: (1) water, (2) fluid soluble material, (3) fluidinsoluble material, (4) erroneous fluid additions, and (5)hydraulic fluid deterioration. Properly designed systems cannormally control water and insoluble contaminants; however,when it is necessary to remove soluble contaminants, a flu
26、idchange and flush are required.5.2 WaterWater is almost always present in hydraulicfluids. It may be present in solution or in a free or emulsifiedform. Water can exist in solution at varying concentrationsdepending on the nature of the fluid, the temperature, and soforth. For example, hydraulic fl
27、uid may hold 50 ppm of waterat 21C (70F) and 250 ppm at 71C (160F). The water insolution has no adverse effect on lubricating properties of thefluid and causes no corrosion; however, when fluid passesthrough a cooler some water may come out of solution andbecome free water in the form of finely disp
28、ersed droplets.Many contaminants hinder the separation of this free waterfrom the fluid by settling and may cause an emulsion. Inhydraulic fluids, the emulsion impairs circulation, interferewith lubrication and adversely affect contamination controlequipment.5.2.1 Water contamination can be classifi
29、ed as either freshor sea water, as encountered in land or marine systems. Freshwater enters the hydraulic system from moist air as condensa-tion, through improperly located vents, leaks in coolers, andsteam heaters, and because of improper operation. Sea water, inmarine hydraulic systems, enters thr
30、ough leaks in coolers,faulty manhole gaskets, faulty sump tank seals and improperlylocated vents. Sea and brackish water can also present a2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume
31、 information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.D4174 89 (2010)2prob
32、lem when used as a coolant in land-based units. Watercontamination in hydraulic fluids can:5.2.1.1 Promote fluid oxidation.5.2.1.2 Reduce fluid stability.5.2.1.3 Promote sludge.5.2.1.4 Promote foaming.5.2.1.5 Form emulsions.5.2.1.6 Promote rusting and corrosion.5.2.1.7 Affect additive and concentrat
33、ion.5.2.1.8 Adversely affect lubricating properties.5.2.1.9 Promote bacteria growth.5.2.1.10 Alter fluid viscosity.5.2.1.11 Adversely affect fine filtration.5.2.2 In the case of severe salt water contamination, it isnecessary to remove the operating fluid and clean and flush thehydraulic systems.5.3
34、 Soluble Contaminants:5.3.1 Soluble contaminants in hydraulic systems includecleaning chemicals, solvents, rust preventives, incompatiblelubricants, flushing oils, extraneous oils, oxidation products,gasket sealants, and assembly lubricants. These contaminantscannot be removed by conventional fluid
35、contamination controlequipment. Normally, a new charge of fluid is required tocorrect the problem. Fluid soluble contaminants can:5.3.1.1 Change the fluid viscosity.5.3.1.2 Alter the flash point.5.3.1.3 Change the color.5.3.1.4 Result in sludge deposits.5.3.1.5 Attack elastomeric seals.5.3.1.6 Initi
36、ate additive-water interaction that can causeemulsification, possible additive loss, instability, impairedpurification equipment performance, foaming, and air entrain-ment.5.3.1.7 Accelerate oxidation.5.3.2 When a soluble contaminant is present, the fluidsupplier and consult the equipment manufactur
37、er should beconsulted regarding the advisability of continued use of thefluid or replacing it with a new charge.5.4 Insoluble Contaminants:5.4.1 Insoluble contaminants normally encountered aremetal particles of all types and sizes, fibers, airborne solids,sand, and other nonmetallic particles. These
38、 contaminants areoften the result of improper manufacturing techniques, im-proper shipping and storage practices, and careless installationof hydraulic systems. Some of the effects of solid contamina-tion are:5.4.1.1 Abrasive wear or sticking of components such as:control valve poppets, cylinders, p
39、iston rods, and seals.5.4.1.2 Faulty control functioning, particularly pluggedfluid lines/filter plugging.5.4.1.3 Reduced fluid stability.5.4.1.4 Sludge formation.5.4.1.5 Increased foaming tendency.5.4.1.6 Stabilized water-oil emulsions/accelerated oxidationby catalytic effect of metal particles.5.4
40、.2 Harmful contamination can exist in the hydraulicsystem in two forms:5.4.2.1 Lodged ContaminationThese contaminants maybecome dislodged by high fluid flows and temperature differ-entials or by induced vibration during flushing. Contaminationcan be lodged in unflushed pockets or settled on the bott
41、om oftanks. Unless this contaminant is removed, it becomes dis-lodged during startup or during system upsets. Experience,good judgement, and careful inspection by the installationsupervisor must be relied upon to determine when such dirt hasbeen satisfactorily removed.5.4.2.2 Suspended Contamination
42、:5.4.2.3 (a) Contaminants suspended in the fluid can begenerated by particles coming loose from pipe, hose, hydrauliccomponents, tank walls generally caused by high fluid velocity,wear debris, and vibration. Suspended contaminant can bemeasured, as described in 11.3. To prevent the level ofsuspended
43、 contaminant from getting beyond acceptable limits,all units should be provided at least with a bypass contamina-tion control system (fluid filter or centrifuge). Preferably a fullflow filter or a full flow filter plus bypass purification isprovided. When a full flow filter is used, a bypass purific
44、ationsystem may not be required.5.4.2.4 (b) The bypass or full flow system, or both, are inoperation during the flush operation as well as on a continuousbasis during hydraulic system operation. The rated flow capac-ity per hour of a bypass system should be 10 to 20 % of thetotal system fluid volume
45、.6. Contamination Control6.1 GeneralContamination control in a hydraulic systemis the complete program of monitoring and maintaining a cleanfluid. Contamination control must begin with the design,manufacture, and installation of the hydraulic system andcontinue throughout the life of the system. Whe
46、n makinginspections or working in or around a unit, care must be takento prevent contaminants from entering the system. When workthat generates contaminants is being performed in the vicinityof the hydraulic system, the system components must beprotected even to the extent of suspending operations,
47、andrequiring system components to be sealed until the contami-nating activity has ceased. The contamination control systemmust be capable of removing water and particulate matterconsistent with contamination tolerance and system cleanlinessrequirements.6.1.1 Initial FillingWhen initially filling the
48、 hydraulicsystem, all fluids are filtered through 3 to 10-m absolute (see4.1) filters as they are being transferred into the reservoir. Thecontamination control system is ready for operation prior to thehydraulic system fill and is operating throughout flushing. SeeSection 9.5.6.1.2 In-Service Units
49、The contamination control systemis in operation as long as the hydraulic system is in service. Itsoperation is frequently and regularly monitored to assure that itis performing adequately and to determine the need for itsmaintenance.6.1.3 Connection of Contamination Control SystemTheexternal fluid take-off from the circulating system to thecontamination control system is from the lowest point of thefluid sump or reservoir, to facilitate removal of solid contami-nants and water.D4174 89 (2010)36.1.3.1 Piping between the reservoir and the contaminationcontrol system is
