1、Designation: D7665 10 (Reapproved 2014)Standard Guide forEvaluation of Biodegradable Heat Transfer Fluids1This standard is issued under the fixed designation D7665; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last r
2、evision. 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 guide2covers general information, without specificlimits, for selecting standard test methods for evaluating heattransf
3、er fluids for quality and aging. These test methods areconsidered particularly useful in characterizing biodegradablewater free heat transfer fluids in closed systems.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.2. Refere
4、nced Documents2.1 ASTM Standards:3D86 Test Method for Distillation of Petroleum Products atAtmospheric PressureD91 Test Method for Precipitation Number of LubricatingOilsD92 Test Method for Flash and Fire Points by ClevelandOpen Cup TesterD93 Test Methods for Flash Point by Pensky-MartensClosed Cup
5、TesterD95 Test Method for Water in Petroleum Products andBituminous Materials by DistillationD97 Test Method for Pour Point of Petroleum ProductsD189 Test Method for Conradson Carbon Residue of Petro-leum ProductsD445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and Calculat
6、ion of Dynamic Viscos-ity)D471 Test Method for Rubber PropertyEffect of LiquidsD524 Test Method for Ramsbottom Carbon Residue ofPetroleum ProductsD664 Test Method for Acid Number of Petroleum Productsby Potentiometric TitrationD893 Test Method for Insolubles in Used Lubricating OilsD1160 Test Method
7、 for Distillation of Petroleum Products atReduced PressureD1298 Test Method for Density, Relative Density, or APIGravity of Crude Petroleum and Liquid Petroleum Prod-ucts by Hydrometer MethodD1500 Test Method for ASTM Color of Petroleum Products(ASTM Color Scale)D2270 Practice for Calculating Viscos
8、ity Index from Kine-matic Viscosity at 40 and 100CD2717 Test Method for Thermal Conductivity of LiquidsD2766 Test Method for Specific Heat of Liquids and SolidsD2887 Test Method for Boiling Range Distribution of Pe-troleum Fractions by Gas ChromatographyD2879 Test Method for Vapor Pressure-Temperatu
9、re Rela-tionship and Initial Decomposition Temperature of Liq-uids by IsoteniscopeD4530 Test Method for Determination of Carbon Residue(Micro Method)D5864 Test Method for Determining Aerobic Aquatic Bio-degradation of Lubricants or Their ComponentsD6384 Terminology Relating to Biodegradability and E
10、co-toxicity of LubricantsD6743 Test Method for Thermal Stability of Organic HeatTransfer FluidsD7044 Specification for Biodegradable Fire Resistant Hy-draulic FluidsE659 Test Method for Autoignition Temperature of LiquidChemicalsG4 Guide for Conducting Corrosion Tests in Field Applica-tions2.2 OECD
11、Standards:4Test No. 203 : Fish, Acute Toxicity Test3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 fluid agingprocess of fluid degradation associatedwith the loss of intended performance of the fluid, which1This guide is under the jurisdiction of ASTM Committee D02 on Petroleu
12、mProducts, Liquid Fuels, and Lubricants and is the direct responsibility of Subcom-mittee D02.L0.06 on Non-Lubricating Process Fluids.Current edition approved Dec. 1, 2014. Published February 2015. Originallyapproved in 2010. Last previous edition approved in 2010 as D7665 10. DOI:10.1520/D7665-10R1
13、4.2The background for this standard was developed by a questionnaire circulatedby ASTM-ASLE technical division L-VI-2 and reported in LubricationEngineering, Vol 32, No. 8, August 1976, pp. 411416.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service a
14、t serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Organisation for Economic Co-operation and Development (OECD), 2, rueAndr Pascal, 75775 Paris Cedex 16, France.Copyright ASTM International, 100 Barr Harbor Drive,
15、 PO Box C700, West Conshohocken, PA 19428-2959. United States1includes fluid composition changes, soot formation, and thedeposit of materials on a surface (fouling).3.1.2 fluid qualitydescribes the fluids appropriateness forthe intended application including factors necessary for safetyand environme
16、ntal awareness or compliance.3.1.3 heat transfer fluidfluid that remains essentially aliquid while transferring heat to or from an apparatus orprocess, although this guide does not preclude the evaluation ofa heat transfer fluid that may be used in its vapor state. Heattransfer fluids may be hydroca
17、rbon or petroleumbased, suchas polyglycols, esters, hydrogenated terphenyls, alkylatedaromatics, diphenyl-oxide/biphenyl blends, and mixtures of di-and triaryl-ethers. Small percentages of functional componentssuch as antioxidants, antiwear and anti-corrosion agents, TBN,acid scavengers, or dispersa
18、nts, or a combination thereof, canbe present.4. Significance and Use4.1 The significance of each test method depends upon thesystem in use and the purpose of the test method as listed underSection 5. Use the most recent editions of ASTM test methods.5. Recommended Test Procedures5.1 Pumpability of t
19、he Fluid:5.1.1 Flash Point, Closed Cup (Test Method D93)This testmethod detects low flash ends which are one cause of cavita-tion during pumping. In closed systems, especially when fluidsare exposed to temperatures of 225C or higher, the formationof volatile hydrocarbons by breakdown of the oil may
20、requireventing through a pressure relief system to prevent dangerouspressure build-up.5.1.2 Pour Point (Test Method D97)The pour point can beused as an approximate guide to the minimum temperature fornormal pumping and as a general indication of fluid type andlow temperature properties. Should a hea
21、t transfer system belikely to be subjected to low temperatures when not in use, thesystem should be trace heated to warm the fluid aboveminimum pumping temperature before start-up.5.1.3 Viscosity (Test Method D445)Fluid viscosity is im-portant for determining Reynolds and Prandtl numbers for heattra
22、nsfer systems, to estimate fluid turbulence, heat transfercoefficient, and heat flow. Generally, a fluid that is aboveapproximately 200 cSt is difficult to pump. The pump andsystem design determine the viscosity limit required forpumping. The construction of a viscosity/temperature curveusing determ
23、ined viscosities can be used to estimate minimumpumping temperature.5.1.4 Specific Gravity (Test Method D1298)Hydraulicshock during pumping has been predicted via the use of acombination of density and compressibility data.5.1.5 Water Content (Test Method D95)The water contentof a fresh heat transfe
24、r fluid can be used to indicate how longthe heat transfer system shall be dried out duringcommissioning, while raising the bulk oil temperature throughthe 100C plus region, with venting, before the system can besafely used at higher temperatures. The expansion tank shouldbe full during the operation
25、s to ensure that moisture is safelyvented in the lowest pressure part of the systems. Positivenitrogen pressure on the heat exchange systems minimizesentry of air or moisture. Heat transfer systems operating attemperatures of 120C or greater shall, for reasons of safety, bedry, because destructive h
26、igh pressures are generated whenwater enters the high temperature sections of the system.Heating the oil before it is placed in service also removes mostof the dissolved air in the oil. If not removed, the air can causepump cavitation. The air can also accumulate in stagnant partsof the system at hi
27、gh pressure and could cause an explosion.5.1.6 Vapor Pressure (Test Method D2879)Vaporpressure, which normally increases with increasing operatingtemperature, is an important design parameter. Organic heattransfer fluids exhibiting high vapor pressures should be usedonly in systems with sufficient s
28、tructural integrity. Operation ofvapor phase systems requires knowledge of the equilibriumvapor pressure.5.2 Safety in Use:5.2.1 Autoignition Temperature (Test Method E659)Thistest relates to the autoignition temperature of a bulk fluid.Hydrocarbon fluids absorbed on porous inert surfaces canignite
29、at temperatures more than 50C lower than indicated byTest Method E659. An open flame ignites leaking hydrocarbonfluids exposed on a porous surface at any temperature.5.2.2 Flash Point (Test Methods D92 and D93)Some heattransfer fluids are volatile and present a fire hazard at slightlyelevated temper
30、atures, or even below 25C.5.2.3 Biodegradation (Test Method D5864)5An environ-mental concern, and toxicity (like acute fish toxicity, seeOECD Test No. 203) is more of an immediate concern forpersonnel that may come into contact with the heat transferfluid as well as plant and animal life that may co
31、me into contactwith effluent that migrates to streams, rivers, or reservoirs.Safety in use information is included a Material Safety DataSheet (MSDS). See Terminology D6384 for terminologyrelating to biodegradability and ecotoxicity. A basis for biode-gradable classification for hydraulic fluids is
32、found in Table 4of D7044-04 and while no specific biodegradability classifica-tions are available for heat transfer fluids, the environmentalpersistence of heat transfer fluids should be evaluated.5.3 Effect on Equipment:5.3.1 Effect on Rubber or Elastomeric Seals (Test MethodD471)Most seals in heat
33、 exchange equipment are made ofsteel or other metal. If rubber seals are present, it is desirableto maintain rubber swelling in the range of 1 to5%topreventleakage because of poor seal contact. Seals may degrade insome fluids. As an oil deteriorates in service, additional testsmay be required to ens
34、ure that seals remain compatible withthe altered oil. The temperature ranges of the tests shouldcorrespond to temperatures to which seals will be exposed inservice.5.3.2 Corrosion (Guide G4)These tests concern selectionof materials of construction with fluids usable for heat transfersystems. Guide G
35、4 uses test metal specimens fixed within the5As heat transfer fluids are mainly used in closed and sealed circuits, this guideis limited to biodegradation issues. An extension to “environmentally friendly” or“ecoevaluated” heat transfer fluids including aquatic toxicities may be an object offuture r
36、evision.D7665 10 (2014)2stream of test fluid under use. The specimens and conditionsfor test shall be specified for each system.5.4 Effciency:5.4.1 Thermal Conductivity (Test Method D2717) and Spe-cific Heat (Test Method D2766)These thermal conductivityand specific heat tests are difficult to carry
37、out, facilities forperforming them are few, and the precision data is yet to beestablished. Values can be estimated for design use from thegeneral chemical composition. Differences contribute to effi-ciency to a lesser degree than values such as viscosity, moisturecontamination, and other measurable
38、 values in 5.1 and 5.5 ofthis guide. The values for thermal conductivity and specificheat may be available from the fluid supplier.65.5 Service Life:5.5.1 Thermal Stability, Laboratory Tests7Thermal stabil-ity is here defined as the resistance of a hydrocarbon liquid topermanent changes in propertie
39、s that make it a less efficientheat transfer fluid. These changes may be related to alterationsin the liquids properties, such as viscosity, or to the tendencyto foul heat exchanger surfaces with insulating deposits.Normally, testing should be done in the absence of air andmoisture to stimulate “tig
40、ht” systems. The test may be usefulfor assessing the remaining service life of a used fluid, or itmay be used to compare the expected service life of competi-tive new heat transfer fluids.5.5.2 The following test methods can be used to determinethe change in values between new and used fluids, or be
41、tweena fluid before and after subjection to a laboratory thermalstability test. These test methods have been found especiallyuseful for determining the end of a fluids service life when anidentical fluid has been monitored with the same tests through-out its service life. These test methods can also
42、 detect leakageof foreign material into the heat transfer fluid.5.5.2.1 Precipitation Number (Test Method D91) and In-solubles (Test Method D893)These test methods determinethe extent to which insolubles that may contribute to fouling ofmetal surfaces are increasing.5.5.2.2 Flash Point (Test Methods
43、 D92 and D93)A low-ering of flash point is indicative of thermal cracking to producelower molecular weight hydrocarbons. A rapid increase mayindicate that fluid is being exposed to excessive temperatures.5.5.2.3 Carbon Residue (Test Methods D189, D524, andD4530)An increase of carbon residue during s
44、ervice pro-vides an indication of the fluids tendency to form carbona-ceous deposits. These deposits, which may impair heat transfer,are caused by precipitation of high molecular weight materialsproduced by thermal cracking of the fluid.5.5.2.4 Viscosity (Test Method D445)An increase in vis-cosity m
45、ay reduce the fluids ability to transfer heat (see 5.1.3).Cracking of hydrocarbons in high temperature service in closedsystems often causes a decrease in viscosity. Thus a change inviscosity taken by itself is insufficient to judge the performanceof a fluid in service.5.5.2.5 Distillation (Test Met
46、hods D86, D1160, andD2887)Distillation can show directly the percentage of afluid that has cracked into lower boiling products or has beenconverted into higher boiling products. Distillation data canserve as the sole criterion for changing a heat transfer fluid.5.5.2.6 Neutralization Number (Test Me
47、thod D664)Amarked increase in neutralization number is a warning ofoxidation in the system, which may be the result of leaks. Inhigh-temperature service (200C), organic acids maydecompose, and the use of infrared analyses may serve as amore reliable method for detection of oxidation.5.5.2.7 Color (T
48、est Method D1500)In itself, color is notimportant, but may be the initial indication of chemicalchanges in the heat transfer system.5.5.2.8 Viscosity Index (Test Method D2270)The viscosityindex of a fluid may change during service. Generally, theviscosity of a heat transfer fluid is not measured at
49、theoperating temperature (see 5.5.2.4). If the viscosity index ofnew and used fluids are known, the viscosities at operatingtemperature can be estimated and compared.5.5.2.9 Water Content (Test Method D95)Small amountsof water present in heat transfer systems may cause corrosion,high pressures, or pump cavitation.6. Keywords6.1 biodegradable; characterization; heat transfer fluid; heattransfer oil; heat transfer systemASTM International takes no position respecting the validity of any patent rights asserted in connection with any item menti
