ASTM_D_3321_-_19.pdf

Designation:D332119Standard Test Method forUse of the Refractometer for Field Test Determination of theFreezing Point of Aqueous Engine Coolants1This standard is issued under the fixed designation D3321;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 parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers the use of a portable refracto-meter for determining the approximate freezing protectionprovided by ethylene and propylene glycol-based coolantsolutions as used in engine cooling systems and specialapplications.NOTE1Some instruments have a supplementary freezing protectionscale for methoxypropanol coolants.Others carry a supplemental scalecalibrated in density or specific gravity readings of sulfuric acid solutionsso that the refractometer can be used to determine the charged conditionof lead acid storage batteries.1.2 The values stated in SI units are to be regarded asstandard.The values given in parentheses after SI units areprovided for information only and are not considered standard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D1177 Test Method for Freezing Point of Aqueous EngineCoolantsE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Summary of Test Method3.1 These coolant testers are critical-angle refractometersdesigned for rapid,approximate measurement of ethylene andpropylene glycol coolant freezing point protection.Only a fewdrops of test solution are required.Some testers automaticallycorrect for ambient air temperature and the temperature of thesolution being tested.The instrument is rugged,simple to read,and easy to clean and maintain.3.2 The coolant freezing point readings are taken at pointswhere the dividing line between light and dark crosses thescales.Some refractometers have a coolant scale for indicatingthe freezing point of aqueous ethylene glycol coolants only,while other refractometers also have a scale for indicating thefreezing point of aqueous propylene glycol coolants.The rangeof the scales varies from one device to another.3.3 Freezing point measurements are concentration-relatedvalues and are in turn directly related to refractive index.It hasbeen empirically determined that freezing point measurementsare accurate within 1 C(2 F).4.Significance and Use4.1 This practice is commonly used by vehicle servicepersonnel to determine the freezing point,in degrees Celsius orFahrenheit,of aqueous solutions of commercial ethylene andpropylene glycol-based coolant.A durable hand-held refracto-meter is available that reads the freezing point,directly,indegrees Celsius or Fahrenheit,when a few drops of enginecoolant are properly placed on the temperature-compensatedprism surface of the refractometer.This refractometer is forglycol and water solutions,and is not suitable for other coolantsolutions.4.2 The hand-held refractometer should be calibrated beforeuse(see Section 7).4.3 Care must be taken to use the correct glycol freezingpoint scale for the glycol type being measured.Use of thewrong glycol scale can result in freezing point errors of 18 andmore degrees Fahrenheit.1This test method is under the jurisdiction of ASTM Committee D15 on EngineCoolants and Related Fluids and is the direct responsibility of SubcommitteeD15.03 on Physical Properties.Current edition approved April 1,2019.Published April 2019.Originallyapproved in 1974.Last previous edition approved in 2013 as D332113.DOI:10.1520/D332119.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World