1、Designation: D8046 16D8046 16aStandard Guide forPumpability of Heat Transfer Fluids1This standard is issued under the fixed designation D8046; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in p
2、arentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope Scope*1.1 This guide covers general information, without specific limits, for selecting and evaluating pumpability characteristics ofheat transfer fl
3、uids at both low and high temperature. This guide is a compendium of information and does not recommend aspecific course of action. This guide provides additional information on pumpability topics found in companion guides forevaluating heat transfer fluids, Guides D5372 and D7665.1.2 Pumpability of
4、 heat transfer fluids is dependent on both fluid properties and the design of the fluid handling system thatstores and transports the fluid, and therefore presents a number of pumping options. This guide is considered particularly usefulfor identifying pumpability options. The listing of test standa
5、rds and guides is not all-inclusive and additional standards and guidesmay be useful.1.3 The values stated in SI units are to be regarded as standard.1.3.1 ExceptionOther units are provided for information only.1.4 This standard does not purport to address all of the safety concerns, if any, associa
6、ted with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. Users of heat transfer fluids should be especially mindful of potential fire and explosion hazards.2. Ref
7、erenced Documents2.1 ASTM Standards:2D92 Test Method for Flash and Fire Points by Cleveland Open Cup TesterD93 Test Methods for Flash Point by Pensky-Martens Closed Cup TesterD97 Test Method for Pour Point of Petroleum ProductsD445 Test Method for Kinematic Viscosity of Transparent and Opaque Liquid
8、s (and Calculation of Dynamic Viscosity)D891 Test Methods for Specific Gravity, Apparent, of Liquid Industrial ChemicalsD2161 Practice for Conversion of Kinematic Viscosity to Saybolt Universal Viscosity or to Saybolt Furol ViscosityD2270 Practice for Calculating Viscosity Index from Kinematic Visco
9、sity at 40 C and 100 CD2879 Test Method for Vapor Pressure-Temperature Relationship and Initial Decomposition Temperature of Liquids byIsoteniscopeD2887 Test Method for Boiling Range Distribution of Petroleum Fractions by Gas ChromatographyD2983 Test Method for Low-Temperature Viscosity of Lubricant
10、s Measured by Brookfield ViscometerD4052 Test Method for Density, Relative Density, and API Gravity of Liquids by Digital Density MeterD5372 Guide for Evaluation of Hydrocarbon Heat Transfer FluidsD6304 Test Method for Determination of Water in Petroleum Products, Lubricating Oils, and Additives by
11、Coulometric KarlFischer TitrationD7042 Test Method for Dynamic Viscosity and Density of Liquids by Stabinger Viscometer (and the Calculation of KinematicViscosity)D7665 Guide for Evaluation of Biodegradable Heat Transfer FluidsE794 Test Method for Melting And Crystallization Temperatures By Thermal
12、Analysis1 This guide is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.L0.06 on Non-Lubricating Process Fluids.Current edition approved July 15, 2016Oct. 1, 2016. Published August 2016October 2016.
13、Originally approved in 2016. Last previous edition approved in 2016 asD8046 16.DOI: 10.1520/D8046-16.10.1520/D8046-16A.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer t
14、o the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all change
15、s accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr
16、Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 cavitation, na process of dropping the local liquid pressure below its vapor pressure due to flow phenomenon and ischaracterized by the formation of vapor
17、 bubbles within the liquid.3.1.1.1 DiscussionImplosion of vapor bubbles on pump components can cause eroding of surfaces, which may lead to decreased pumpingperformance and mechanical failures.3.1.2 heat transfer fluid, na fluid that remains essentially a liquid while transferring heat to or from an
18、 apparatus or process,although this guide does not preclude the evaluation of a heat transfer fluid that may be used in its vapor state.3.1.2.1 DiscussionHeat transfer fluids may be hydrocarbon- or petroleum-based such as polyglycols, esters, hydrogenated terphenyls, alkylatedaromatics, diphenyl-oxi
19、de/biphenyl blends, mixtures of di- and triaryl-ethers. Small percentages of functional components such asantioxidants, anti-wear and anti-corrosion agents, TBN, acid scavengers ,and/or dispersants can be present.3.1.3 pumpability, na fluid characteristic related to its ability to deform (shear stre
20、ss-shear rate relationship) or ability to flow.3.1.3.1 DiscussionThere is no specific value associated with pumpability, although as a practical matter, the term is associated with the ability ofpumps to flow a fluid at a specific temperature. Some producers of heat transfer fluids provide the tempe
21、rature at which the fluidattains a specific viscosity value that may be associated with pumping limits. For example, it is common to find temperature valuesof heat transfer fluids for viscosities of 300 cSt (300 mm2/s) and 2000 cSt (2000 mm2/s). The pump design and its installation willdetermine the
22、 viscosity limit for pumpability of a heat transfer fluid.4. Significance and Use4.1 Pumpability of heat transfer fluids depends upon the configuration of the system in use, pumps and their installation, andthe physical properties of the fluids being transported. The fluids ability to pump efficient
23、ly is key to the economy of the systemoperation and heat transfer fluid life. The test methods listed in Section 5 may be considered as guides for determining thepumpability of heat transfer fluids under specific operating conditions. Information gained from use of this guide will aid in theselectio
24、n of pumping equipment and its installation.5. Relevant Tests for Characterization of Fluid Pumpability5.1 Flash Point, open cup or closed cup (Test Method D92, D93)This test method will detect low flash ends which are onecause of cavitation during pumping. In closed systems, especially when fluids
25、are exposed to temperatures of 225 C(approximately 400 F) or higher, the formation of volatile hydrocarbons by breakdown of the fluid may require venting througha pressure relief system to prevent dangerous pressure build-up.5.2 Pour Point (Test Method D97)The pour point may be used as an approximat
26、e guide to what is known as the “borderlinepumpability temperature,” or bpt, and is a general indication of the lowest temperature a fluid can be pumped. If a heat transfersystem is subjected to low temperatures when not in use, a heat trace system should be employed to warm the fluid above minimump
27、umping temperature before start-up.5.3 Crystallization Temperature (Test Method E794)Crystallization or freezing is a condition of solid formation and no liquidpump will work in this region.5.4 Viscosity (Test Method D445, D2983, D7042)Fluid viscosity is important for determining Reynolds and Prandt
28、l numbersfor heat transfer systems, to estimate fluid turbulence, heat transfer coefficient, and heat flow. Fluids become more difficult to pumpas their viscosity becomes higher. See 6.1 for pumping of viscous fluids.5.5 Specific GravityRelative Density (Test Method D891, D4052)Specific gravityRelat
29、ive density of heat transfer fluids is aparameter needed for calculating fluid density which is used in performance calculations for heat transfer, fluid dynamics, andpumping power. Also, hydraulic shock during pumping is predicted via the use of a combination of density and compressibilitydata. Tes
30、t methods such as those described in Test Method D4052 will provide direct measures of density. Also, hydraulic shockduring pumping is predicted via the use of a combination of density and compressibility data. Specific gravity of a liquid is relatedto density bydensity where density is reported at
31、a specific temperature or when reporting relative density, both test temperatureand reference temperature are given (for example, relative density 20 C the following:20 C = 0.xxxx).D8046 16a2SGliquid5liquid water5liquid 1000 kg/m3 (1)where the density of water is taken at 4 C.5.6 Water Content (Test
32、 Method D6304)Use the water content of a heat transfer fluid to indicate when the heat transfer systemhas been dried out sufficiently. Consider raising the bulk fluid temperature through the 100 C plus region, to allow venting of watervapor, before proceeding to operate the system at higher temperat
33、ures. The system expansion tank shall be full prior to startup toensure that moisture is safely vented in the lowest pressure part of the system. Positive nitrogen pressure on the heat transfer fluidsystem will minimize entry of air or moisture. Heat transfer systems operating at temperatures of 120
34、 C or greater shall, forreasons of safety, be dry, contain little moisture, because destructive high pressures are generated when water enters the hightemperature sections of the system. The fluid supplier should be consulted to determine how low the moisture level in the heattransfer fluid must be
35、maintained for safe system operation. Heating the fluid before it is placed in service also removes most ofthe dissolved gasses in the fluid. If not removed, these gasses can cause pump cavitation. (WarningAir and combustible gassescan accumulate in stagnant parts of a poorly designed system and for
36、m a region of high potential for explosion.)5.7 Vapor Pressure (Test Method D2879)Vapor pressure, which normally increases with increasing operating temperatures,is an important design parameter. Heat transfer fluids exhibiting high vapor pressures shall be used only in systems with sufficientstruct
37、ural integrity. Design and operation of vapor phase systems will require knowledge of the equilibrium vapor pressure. Vaporpressure is an important consideration when investigating cavitation potential of a pumping system. Vapor pressure and other fluidproperties may change as the fluid ages.5.8 Vis
38、cosity Conversions and CalculationsViscosity information provided with heat transfer fluids may be either in units ofabsolute or kinematic viscosity or both for specific temperatures. Information is sometimes provided for pumpabilitycharacterization in terms of a specific viscosity at a given temper
39、ature. Practices D2161 and D2270 provide calculation methodsfor conversion of units.5.9 Boiling Range Distribution (Test Method D2887)The flow characteristics of heat transfer fluids, especially viscosity, canchange due to changes in composition caused by thermal degradation, oxidation, venting of l
40、ow boiling components, and otherprocesses as the fluid ages. Boiling range distributions obtained by Test Method D2887 will give insight about fluid degradationand hence pumpability characteristics especially for ageing fluids.6. Pumps and Installation (Informational Only)6.1 PumpsCentrifugal, gear,
41、 canned motor and magnetically coupled pumps are commonly used to pump heat transfer fluids.Selection of a pump type depends on numerous factors relating to cost of operation and fluid handling characteristics of the pump.Key fluid handling factors are fluid viscosity and net positive suction head r
42、equired. Heavy duty centrifugal pumps are mostcommon for pumping heat transfer fluids and are used with fluids with viscosity as high as 400 cP (400 mPas) (400 cSt with aspecific gravity of 1.0) as a practical limit. For low temperature and high viscosities to approximately 2000 cP (2000 mPas), gear
43、pumps are typically recommended. Use canned motor and magnetically coupled pumps to avoid leakage of heat transfer fluid.Because of viscous drag on rotating parts of a pump, horsepower requirements can be significantly increased when pumping highlyviscous heat transfer fluids in the 80 C to 10 C tem
44、perature range. Typical seals used are packing glands, mechanical, andcombinations of the two. For high temperature operation, provisions are needed for cooling of seals and bearings. The capacityof a rotary pump varies directly with relative speed, and is independent of pressure within its operatin
45、g limits. Volumetric efficiencygenerally increases with increasing viscosity; however, overall mechanical efficiency will suffer at both high viscosities and verylow viscosity. The approximate viscosity limit for rotary pumps is 4 105 cSt.6.2 InstallationExcessive pressure loss in the inlet piping t
46、o a heat transfer fluid pump may lead to severe cavitation at thepump inlet. As inlet fluid velocity increases and the pressure at the inlet drops, the local pressure may approach the fluid vaporpressure resulting in cavitation issues. Ensure there is sufficient net positive suction head at the pump
47、 inlet to prevent cavitation.Net positive suction head available can be increased by increasing the blanket gas pressure at the expansion tank. The pump suctionhead requirement for a given inlet flow rate, known as the net positive suction head requirement (NPSHR) is dependent on thepump design and
48、this data is supplied by the pump manufacturer. The user needs to determine the lowest possible heat transferfluid temperature that can occur for the installation, determine the viscosity of new fluid at that temperature, consider how fluidchanges due to degradation may increase fluid viscosity, and
49、 apply an appropriate safety factor to the maximum fluid viscosity.The user should select a pump and motor combination which can accommodate that maximum fluid viscosity. The motor shouldbe large enough to handle the pump requirements when starting up and operating with the maximum fluid viscosity.7. Keywords7.1 characterization; heat transfer fluid; pumpabilityD8046 16a3SUMMARY OF CHANGESSubcommittee D02.L0 has identified the location of selected changes to this standard since the last issue(D8046 16) that may impact the use of this
